An occluded state and an opened state are reproduced on an occluding apparatus by a pair of upper and lower dentiform models using a bite at the time of occlusion and a bite at the time of opening which are extracted from a patient. For the reproduction, a D plate (Dual Mounting Plate) 9 is used. When the D plate 9 is used, it is possible to produce a C block which is integrated with an upper jaw teeth mode 4 by gypsum and an S1 block (or an S2 block) for a spacer which is mounted between the C block and an upper mounting plate 11 (12). The occluded state and the opened state can be reproduced using the dentiform models by replacing the S1 block and the S2 block with each other.

1. Field of the Invention
The present invention relates to a method of an auxiliary tool used when a dentiform model is mounted on an occluding apparatus and a method of mounting the dentiform model on the occluding apparatus. Particularly, it relates to an auxiliary tool for an occluding apparatus which is suitable for production of a tooth positioner used in the final stage, for example, of orthodontic treatment and a method of mounting a dentiform model.
2. Prior Art
In clinical orthodontics, a tool referred to as a tooth positioner has been known as an apparatus used in the final stage of orthodontic treatment for attaining closer occlusion and slightly moving the teeth of a patient in cases such as a case where a relapse occurs in a short time after the orthodontic treatment. The tooth positioner is produced on the basis of a set-up model of the patient, which is made by separating teeth of a dentiform model made on the basis of an impression of the upper and lower Jaws of the patient as required and rearranging the separated teeth in an ideal set of teeth and in an ideal occluded state on the model.
The tooth positioner has a structure similar to a mouse piece (used in sports such as boxing), and is made of a material having elasticity and an original form restoring force, for example, rubber or silicon, so that an ideal set of teeth on the set-up model is carved thereon. When the tooth positioner is mounted in the mouth of the patient, the tooth positioner is first deformed by the difference between the actual set of teeth of the patient and the set of teeth on the set-up model which is carved in the tooth positioner. Thereafter, a continuous weak force is applied to the set of teeth during a mounting period by the original form restoring force of the tooth positioner, to finally move the teeth of the patient to an ideal position indicated by the set-up model. The use of the apparatus eliminates the necessity of using a complicated apparatus in the final stage of the orthodontic treatment, or makes it possible to shorten a period during which a complicated apparatus is mounted. In recent years, such usefulness has been reconsidered, so that the tooth positioner tends to be relatively often used.
FIG. 1 is a perspective view showing an example of a tooth positioner, and FIG. 2 illustrates the tooth positioner in a state where it is mounted in the mouth of a patient. An ideal set of teeth 2 on a set-up model is carved, as described above, in a tooth positioner 1. The set of teeth of the upper jaw 2 and a set of teeth of the lower jaw (not shown) are generally carved.
When the tooth positioner 1 is mounted in the mouth, the set of teeth 2 carved in the tooth positioner 1 and actual sets of teeth T.sub.U and T.sub.D of a patient are engaged with each other. However, after the tooth positioner 1 is deformed by the difference therebetween. A continuous weak force is applied to the actual sets of teeth T.sub.U and T.sub.D by an original form restoring force. The applied force is illustrated by + and - in FIG. 2.
In the tooth positioner 1, however, an occluded surface between the set of teeth of the upper Jaw T.sub.U and the set of teeth of the lower jaw T.sub.D (a surface where the upper and lower teeth are occluded) is covered with its material, so that the tooth positioner 1 is interposed between the upper and lower sets of teeth T.sub.U and T.sub.D (an area indicated by 3 in FIG. 2). That is, when the tooth positioner 1 is mounted, the upper jaw and the lower jaw are opened. Actually, the upper jaw is fixed to the head, so that the lower jaw is opened downward toward the back using the jaw joint as its axis.
The set-up model for the patient is made in a state where the respective sets of teeth of the upper jaw and the lower jaw are occluded. The reason for this is that the occluded surface and the size and the shape of the teeth differ from patient to patient, so that the arrangement of the teeth in an ideal occluded state cannot be presumed.
On the other hand, the tooth positioner is produced in a state where the set-up model made in the occluded state is opened by a suitable amount, that is, the upper and lower jaws are opened by the thickness of the tooth positioner to be interposed between the respective sets of teeth of the upper jaw and the lower jaw.
Consequently, the setting of a state where the jaws are moved when they are opened must conform to the anatomical and physiological functions in the jaw joints of the patient. Otherwise the respective sets of teeth of the upper and lower jaws would not be actually satisfactorily occluded, or would be occluded in an erroneous relationship between the upper and lower jaws after detaching the tooth positioner even if they are respectively regularly corrected by using the tooth positioner. As a result, the sets of teeth may be shifted immediately after the orthodontic treatment, and an excessive burden may be imposed on the jaw joints which correct the shift in the relationship between the upper and lower jaws for each bite. In either case, the mounting itself of a tool produced by unsuitably setting the relationship between the upper and lower jaws distorts the position of the lower jaw, thereby imposing a burden on the jaw joint.
In order to remove such harmful effects, an occluding apparatus and a side X-ray have been conventionally used in setting the amount of opening between the upper and lower jaws.
The occluding apparatus is an apparatus for connecting the upper jaw, the lower jaw and the dentiform model to one another, to reproduce the motion of the jaw joints of a human being. However, the apparatus is an apparatus for confirming a state where the sets of teeth are occluded, and the motion of the jaw joints is only reproduction of a certain degree of average motion. That is, the occluding apparatus has not been able to correctly reproduce the motion of the jaw joints for each patient.
Consequently, it is impossible to faithfully reproduce a state where the upper and lower jaws of each patient are opened by merely using the occluding apparatus.
A method using the side X-ray is a method of respectively tracing the set of teeth of the upper jaw and the set of teeth of the lower jaw on an X-ray of the face taken from just beside the face, opening the set of teeth of the lower jaw using the jaw joint as its axis, referring to the distance between the sets of teeth of the upper and lower jaws (a clearance) which occurs at that time, and setting the motion of the jaw joint. However, the method has the disadvantage in that it is almost impossible to clearly take an X-ray of the left and right jaw joints with they being exactly overlapped with each other. Even if the X-ray can be taken, the accuracy of the X-ray is not sufficient in that the motion in a three-dimensional manner of a state where the upper and lower jaws of the patient are opened is represented in a two-dimensional manner by the X-ray taken from just beside the face.
When the foregoing is considered, it will be said that a method of recording a state where the patient actually bites and a state where the jaws are opened by the thickness of the tooth positioner and reproducing the two types of states on the occluding apparatus is most accurate in order to know the relationship between the upper and lower jaws. The reason for this is that it is not so difficult for a skilled dentist to set the correct occlusion and opening positions of the patient in the mouth of the patient and make a recording of the relationship between the upper and lower jaws (hereinafter referred to as "bite"). In order to take a bite, a material which is mainly composed of silicon and is superior in operability and reproducibility is easily available.
However, it was infeasible from the following reasons to reproduce the two types of relationships between the upper and lower jaws at the time of occlusion and at the time of opening an occluding apparatus using two types of bites extracted from the patient.
In mounting the dentiform model on the occluding apparatus, there are currently a method of directly fastening upper and lower jaw teeth models, respectively, to portions, corresponding to the upper jaw and the lower jaw, of the occluding apparatus by gypsum and a method of fixing a dentiform model to the occluding apparatus using a magnet or a screw such that the dentiform model is detachable from the occluding apparatus as required. In the latter method, a mounting plate of a magnet type or a screw type or a so-called split cast is generally used. In producing the tooth positioner, the latter method in which the dentiform model is detachable from the occluding apparatus is suitable in terms of technical operations.
Consider a case where the relationships between the upper and lower jaws in two states, that is, a state where the respective sets of teeth of the upper and lower jaws are occluded and a state where they are opened by the thickness of the tooth positioner are reproduced on the occluding apparatus utilizing the two types of bites extracted in the mouth of the patient. In reproducing the two types of states on the occluding apparatus, it is considered that the upper jaw teeth model is mounted in the following two types of methods without changing the position where the lower jaw teeth model is mounted.
(1) Only two upper jaw teeth models which are the same are prepared, to respectively be mounted, using the bite extracted in the occluded state and the bite extracted in the opened state, the two states on an upper jaw portion of the occluding apparatus.
In this case, two types of blocks A and B for the upper jaw, including an upper jaw teeth model 4, are formed, as shown in FIGS. 3 (A) and 3 (B) (the A block reproduces the occluded state, and the B block reproduces the opened state). Accordingly, the two types of relationships between the upper and lower jaws can be reproduced by replacing the two blocks A and B with each other on an occluding apparatus 100.
Even if teeth of the dentiform model in the occluded state shown in FIG. 3 (A) are separated, and the separated teeth are newly rearranged, to make a set-up model, however, the set-up model cannot be brought into the state shown in FIG. 3 (B), that is, the opened state. Conversely, a set-up model cannot be produced from the dentiform model in the opened state shown in FIG. 3 (B). The reason for this is that the form of the teeth differs from patient to patient, so that the arrangement of the teeth in the occluded state cannot be presumed from the opened state, and the set-up model cannot be made from the dentiform model which is not in the occluded state.
(2) As another method, consider a method of reproducing the two types of relationships between the upper and lower jaws not using the two upper jaw teeth models but using a pair of upper and lower jaw teeth models. In this case, a state at the time of occlusion is obtained, in the same manner as that shown in FIG. 3 (A), as shown in FIG. 4 (A). However, an attempt to reproduce a state at the time of opening brings about the necessity of opening an upper jaw portion 5 of the occluding apparatus 100 itself, as shown in FIG. 4 (B).
The occluding apparatus 100 reproduces the motion of the jaw joints of a human being in approximate or average fashion, and does not faithfully reproduce the motion of the jaw joints of each patient, as described above. Even if an attempt to finely adjust the position where the A block is mounted with a bite 6 interposed between the lower jaw teeth model and the upper jaw teeth model is made in the state shown in FIG. 4 (B), the upper jaw teeth model 4 cannot be so adjusted as to fit the bite 6.
An attempt to make the adjustment brings about the necessity of further fastening the B block for correction on the A block.
In this case, even if the relationship between the upper and lower jaws at the time of opening can be reproduced, the B block for correction is fastened to the A block. In the A block A plus B block, therefore, the occluded state shown in FIG. 4 (A) cannot be reproduced even if the upper jaw portion 5 of the occluding apparatus 100 is lowered (closed).
As apparent from the foregoing consideration, in the method currently used, it is impossible to reproduce the two types of relationships between the upper and lower jaws which are required to produce the tooth positioner on the occluding apparatus.

Auxiliary tool for occluding apparatus and method of mounting dentiform model on occluding apparatus

c/o Kim Orthodontic Clinic, Pain Kurakuen 2F, 3-3

Ishibane-cho, Nishinomiya-shi, Hyogo-ken 662-0074


In a stencil printer, an elastic member is provided on a master conveying path from a roll of master sheet to a master pinch drum. The elastic member is pressed against the master sheet to apply back tension to the master sheet when the master sheet is moved by rotation of the master pinch drum after the leading end of the master sheet has been clamped to the clamp portion of the master pinch drum.

1. Field of the Invention
The present invention relates to a stencil printer equipped with a master making section, and more particularly to structure for applying back tension in wrapping a perforated stencil paper (hereinafter referred to as a perforated master sheet) around a master pinch drum.
2. Description of the Related-Art
A conventional stencil printer equipped with a master making section is shown, for example, in Japanese Patent Publication No. 2538817. Master conveying rollers and master discharging rollers are provided behind the master making section to warp a perforated master sheet around a master pinch drum after the perforated master sheet has been made. When making the perforated master sheet, the master discharging rollers are stopped and the master conveying rollers are rotated to slacken the perforated master sheet between the discharging and conveying rollers and store the slack part therebetween. At the time the master making process has ended, the master pinch drum with the leading end of the master sheet clamped to the clamp portion of the drum is rotated to wrap the master sheet around the drum, while tension is being applied to the master sheet by the discharging rollers.
In the process of wrapping the master sheet around the drum, it is important from the standpoint of obtaining an accurate master-wrapped state to apply stable back tension to the master sheet when the master sheet, the leading end of which is clamped to the clamp portion of the drum, is wrapped around the drum by rotation of the drum. However, in the aforementioned stencil printer, there is a danger that stable back tension cannot be applied to the master sheet, because back tension is applied only by rotation of the discharging rollers resulting from movement of the master sheet.
That is, when the perforated master sheet is wrapped around the master pinch drum, the master sheet has been slackened and stored on an upstream side from the discharging rollers. In this state, in the case where back tension is applied to the master sheet only by the rolling resistance which occurs due to rotation of discharging rollers caused by movement of the master sheet, a certain degree of back tension can be applied at the moment the master sheet starts moving from the stopped state thereof to rotate the master discharging rollers. However, after the discharge rollers have started rotating, it is mechanically difficult to apply stable back tension to the master sheet because of load fluctuation in the rotation of the discharging rollers.
The present invention has been made in view of the aforementioned problems found in the aforementioned stencil printer. Accordingly, the primary object of the present invention is to provide a stencil printer which is capable of performing an accurate master wrapping operation by applying stable back tension when a master sheet with the leading end clamped to a master pinch drum is wrapped around the drum.
To achieve this end and in accordance with one important aspect of the present invention, there is provided a stencil printer wherein an elastic member is provided on a master conveying path from a roll of unperforated master sheet to a master pinch drum, the elastic member being pressed against a perforated master sheet to apply back tension to the perforated master sheet when the perforated master sheet is moved by rotation of the master pinch drum after the leading end of the perforated master sheet has been clamped to the clamp portion of the master pinch drum.
In accordance with another important aspect of the present invention, there is provided a stencil printer wherein
along a master conveying path from a roll of unperforated master sheet to a master pinch drum, a master making section, master conveying rollers, and master discharging rollers are disposed in order so that a perforated master sheet is slackened between the master conveying rollers and the master discharging rollers; and
an elastic member is provided between the master discharging rollers and the master pinch drum, the elastic member being pressed against the perforated master sheet to apply back tension to the perforated master sheet when the perforated master sheet is moved by rotation of the master pinch drum after the leading end of the perforated master sheet has been clamped to the clamp portion of the master pinch drum.
In accordance with still another important aspect of the present invention, there is provided a stencil printer wherein
along a master conveying path from a roll of unperforated master sheet to a master pinch drum, a master making section, master conveying rollers, and master discharging rollers are disposed in order so that a perforated master sheet is slackened between the master conveying rollers and the master discharging rollers; and
an elastic member and a smoothing member are provided between the master discharging rollers and the master pinch drum, the smoothing member being fixed with the stencil printer, the elastic member being pressed against the smoothing member through the perforated master sheet to apply back tension to the perforated master sheet when the perforated master sheet is moved by rotation of the master pinch drum after the leading end of the perforated master sheet has been clamped to the clamp portion of the master pinch drum.
In a preferred form of the present invention, the master discharging rollers apply no load to the perforated master sheet being moved, when the elastic member is in pressing contact with the perforated master sheet.
In another preferred form of the present invention, a mechanism for adjusting a force that the elastic member is pressed against the smoothing member through the perforated master sheet is provided.
According to the present invention, an elastic member is provided on a master conveying path from a roll of master sheet to a master pinch drum and is pressed against the master sheet being moved by rotation of the master pinch drum so that back tension is applied to the master sheet. With this arrangement, a constant and stable back tension can be applied to the master sheet being moved, by the sliding resistance which occurs when the elastic member is pressed against the master sheet. As a result, master-wrapping precision is enhanced, whereby printing quality can be enhanced.
The aforementioned tension blade is disposed between the discharging rollers, which slackens and stores the perforated master sheet, and the master pinch drum. With this arrangement, stable back tension can be applied even at the final stage of wrapping the master sheet around the drum and therefore an accurate master-wrapping operation can be performed. Furthermore, since the master discharging rollers apply no load to the master sheet when the tension blade is in pressing contact with the master sheet, load fluctuation resulting from rotation of the discharging rollers caused by movement of the master sheet can be suppressed and therefore stable back tension can be applied to the master sheet.


Provided is a battery module in which weldability between electrode leads and/or between an electrode lead and a bus bar is improved. The battery module includes: a cell assembly that includes a plurality of secondary batteries stacked in at least one direction, respectively including electrode leads, and electrically connected to each other via a connection between the electrode leads; and at least one bus bar that includes an electrically conductive material and is electrically connected by contacting the electrode leads of the plurality of secondary batteries, wherein at least one of the electrode leads is combined and fixed to at least one of another electrode lead and the at least one bus bar, which are contacted by the at least one of the electrode leads, via a welding spot formed in a tornado shape.

Recently, demands for portable electronic products, such as laptop computers, smart phones, smart watches, etc. have rapidly increased, and development of batteries for energy storage, robots, and satellites, etc. has regularized, and thus studies on high performance secondary batteries capable of repetitive charging and discharging are actively conducted.
Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries, and thereamong, the lithium secondary batteries are in the limelight because the lithium secondary batteries have almost no memory effect compared to a nickel-based secondary battery and thus is free of being charged and discharged, has a very low self-discharge rate, and has high energy density.
In such a lithium secondary battery, a lithium-based oxide and a carbon material are respectively mainly used as a positive electrode active material and a negative electrode active material. The lithium secondary battery includes an electrode assembly, in which a positive electrode plate and a negative electrode plate on which the positive electrode active material and the negative electrode active material are respectively coated are arranged with a separator therebetween, and an exterior material, i.e., a battery case, sealing and accommodating the electrode assembly with an electrolyte solution.
Generally, the lithium secondary battery may be classified into a can-type secondary battery, in which the electrode assembly is embedded in a metal can, and a pouch-type secondary battery, in which the electrode assembly is embedded in a pouch of an aluminum laminate sheet.
Recently, the secondary batteries are widely used not only in a small-sized apparatus, such as a portable electronic device, but also in medium- and large-sized apparatuses, such as a vehicle or a power storage apparatus. In particular, with the gradual depletion of carbon energy and the increase in the interest in an environment, attention is focused on hybrid vehicles and electric vehicles worldwide including US, Europe, Japan, and Korea. The most important component in the hybrid vehicle or electric vehicle is a battery pack that provides a driving power to a vehicle motor. Since the hybrid vehicle or electric vehicle obtains the driving power via charging and discharging of the battery pack, fuel efficiency is excellent compared to a vehicle using only an engine and pollutants are not discharged or reduced, and thus users are steadily increasing.
Most battery packs, in particular, medium- and large-sized battery packs for hybrid vehicles, electric vehicles, or energy storage systems (ESSs), include a plurality of secondary batteries, and such plurality of battery packs are connected to each other in series and/or parallel to for improvement in capacity and output. In addition, a pouch type secondary battery is mostly used in the medium- and large-sized battery packs owing to advantages, such as easy stacking, a light weight, and a possibility that a large number of pouch type secondary batteries can be included, etc.
In such a pouch type secondary battery, an electric connection between secondary batteries is mostly configured by directly contacting electrode leads to each other. Here, In order to connect the secondary batteries in parallel, the electrode leads of same polarity are connected to each other, and in order to connect the secondary batteries in series, the electrode leads of different polarities are connected to each other.
Also, for an electric connection and/or voltage sensing of the secondary battery, a bus bar may be bonded to the electrode lead, in particular, at least two electrode leads. At this time, the electrode lead and the bus bar may be bonded often via a welding method.
FIG. 1 is a partial perspective view schematically showing a configuration in which an electrode lead and a bus bar are welded to each other in a general battery module. Also, FIG. 2 is a cross-sectional view taken along a line A1-A1′ of FIG. 1, in which a welded portion is illustrated.
Referring to FIGS. 1 and 2, when two electrode leads 10 and one bus bar 20 are welded to each other in the general battery module, the welding is mostly performed in a linear form as indicated by a reference character A2. Also, a length direction of a welding line at this time is a width direction of an electrode lead.
However, according to such general welding between the electrode lead 10 and the bus bar 20, weldability is low. In particular, such welding is performed mainly via a laser welding method, and since a welded portion is very hardened by a laser beam, the welding portion may be vulnerable to an impact or vibration.
Furthermore, according to such a general welding configuration, when a pore or crack is generated inside the welded portion, the crack may very rapidly grow due to external vibration or an impact. For example, when a crack is generated at a point A3 of FIG. 1, the crack may be quickly enlarged in a direction indicated by an arrow A4, i.e., a length direction of a welding line, by vibration or an impact.
In particular, a direction to which an external force is applied may be a direction perpendicular to the welding line (a left-and-right direction of FIG. 1), and in this case, a cross-sectional area of the welded portion is small in the direction to which the external force is applied, and thus welding targets may be detached from each other even in a low tensile force. Furthermore, according to a general linear welding configuration, a crack often starts from one end of the welding line. Then, the crack may continuously grow along the welding line.
Moreover, according to such a general linear welding configuration, welding strength at one end may be decreased. For example, in the configuration of FIG. 1, welding may be performed as a laser beam is irradiated from one end of the welding line continuously to the other end, but sufficient heat may not be transferred to an electrode lead at a portion where the welding starts, and thus welding strength may be decreased.
As such, according to a general welding configuration between electrode leads and/or between an electrode lead and a bus bar, weldability is low and particularly, vulnerability to vibration or an impact is high. Moreover, when the battery module is applied to a vehicle, the battery module is exposed to a large amount of vibration or impact, and thus weldability for a connection of the electrode lead and/or bus bar needs to be stably secured.


Various systems and methods for generating error indications are disclosed herein. In some cases, the error indication is used as an erasure pointer in a memory access system. As one particular example, a system for generating an erasure pointer is disclosed that includes accumulating a number of error values into an overall error value, and comparing the overall error value to an error threshold. When the overall error value exceeds the error threshold, an erasure pointer is generated. In one particular case, the error values are derived from a look up table using thermometer codes generated by an analog to digital converter. In other cases, the error values are derived from comparing a soft output with a reliability threshold.

The present invention is related to systems and methods for accessing a storage medium, and more particularly to systems and methods for generating erasure flags in relation to storage media access.
When accessing information from a storage medium various errors can occur. To compensate, one or more encoding/decoding schemes are utilized that allow for error correction of the information accessed from the storage medium. For example, various hard disk drives utilize a Reed Solomon decoder to detect and correct errors in a received data stream. However, where too many errors exist in the data stream a Reed Solomon decoder may not come to a conclusion. To avoid this, one or more systems may indicate an overabundance of errors by setting an erasure flag. Such erasure flags have historically been generated based on criteria such as thermal asperity events and modulation-code violations. Such criteria offer some utility, but do not offer a desirable level of coding gain.
Hence, for at least the aforementioned reasons, there exists a need in the art for advanced systems and methods for generating error indications.

Systems and methods for generating erasure flags


An inkjet printing method includes providing an inkjet composition, which includes a radiation curable monomer or oligomer, a photo-initiator, and an inhibitor present in an amount sufficient to prevent full curing of the radiation curable monomer or oligomer during an initial exposure to a curing energy. First drops of the inkjet composition are deposited onto a substrate. The curing energy is selected such that it is sufficient to substantially consume the inhibitor. The first drops are exposed to the curing energy, whereby the first drops retain substantially a same surface tension as a liquid drop of the inkjet composition. Second drops of the inkjet composition are deposited adjacent to the first drops. The first and second drops are exposed to the curing energy, whereby the first drops are at least partially cured and the second drops retain substantially the same surface tension as a liquid drop of the inkjet composition.

In addition to home and office usage, inkjet technology has been expanded to high-speed, commercial and industrial printing. Inkjet printing is a non-impact printing method that utilizes electronic signals to control and direct droplets or a stream of ink to be deposited on media. Current inkjet printing technology involves forcing the ink drops through small nozzles by thermal ejection or by piezoelectric pressure or oscillation onto the surface of the media. This technology has become a popular way of recording images on various media surfaces (e.g., paper), for a number of reasons, including, low printer noise, capability of high-speed recording and multi-color recording.

Hewlett-Packard Industrial Printing LTD.


An apparatus for fracturing wells employs a propellant charge and an ignition cord wrapped around the outer surface of the propellant charge to rapidly ignite the outer surface of the propellant charge.

1. Field of the Invention
The present invention relates generally to the field of well fracturing. More specifically, the present invention discloses a propellant assembly for fracturing wells.
2. Statement of the Problem
Propellant charges have been used for many years to create fractures in oil, gas and water formations surrounding a well. FIG. 1 is a cross-section diagram of a well 10 with a packer 12 and a series of propellant charges 20. The propellant charges 20 are ignited to rapidly generate combustion gases that create sufficient pressure within the well bore to generate fractures in the surrounding strata.
In order to achieve proper pressure loading rates and adequate minimum pressures for sustained periods of time sufficient to extend fractures in the surrounding formations using gas-generating propellants, it is necessary that a sufficient surface area of propellant be burning to generate the volume of gas required to extend such fractures, as gas generation is a function of the surface area of the propellant burning at any given time. If ignition of the propellant is limited to small areas of the outer surface of the propellant, then the flame from the initial burning area of the propellant must spread across the face of the propellant to ignite the remaining surface area. This flame spread rate is a key limiting factor to achieving proper pressure loading rates and adequate minimum pressures for fracture propagation in the surrounding formations. If the flame spread from a localized ignition point is too slow, then the burning surface area at any given point in time will be limited, and the overall time that the propellant burns to completion may have to be extended sufficiently to compensate for the reduced amount of time that pressures exceed the minimum required fracture extension pressure, resulting in a longer but less efficient propellant burn.
In addition, the propellant burn should be predictable and reproducible for the purpose of accurately modeling the fracturing process. It is difficult to accurately model a propellant burn unless the entire exposed surface of the propellant is ignited almost simultaneously. Modeling of propellants has been contemplated in the past, but with the assumption that ignition of the propellant surface over the entire exposed area of the propellant is simultaneous. Practically speaking, such simultaneous ignition is difficult to achieve.
The problem is further complicated by the following. When propellants are submerged in well fluids such as water (or water and KCI), flame spread rates tend to decrease. In addition, certain chemical coverings that are used as surface coatings on propellants to prevent leaching of the propellant fuel oxidizers into the surrounding well fluids also tend to inhibit the flame spread rate, thus exacerbating the problem. When such coatings are not applied to the surface of the propellant, sufficient leaching of the fuel oxidizer takes place over relatively short periods of time (i.e., 1 hour) to result not only in a reduction in the available energy to do work on the formation, but further, creation of an outer boundary layer absent of fuel oxidizer and comprised primarily of the propellant binder, which tends to inhibit the flame spread rate because the exposed fuel oxidizer in the binder has been leached away. Furthermore, because gas generation is a function of the area of propellant burning at any given time, it is also useful to engineer a propellant fracturing system that accounts for the required initial burning surface area to provide adequate pressure rise, in addition to taking into account the flame spread rate.
In summary, the problem consists of igniting sufficient surface area of propellant simultaneously to overcome the effects of not only a limited flame spread rate, but also to mitigate the effects of any sealing coating placed on the propellant. In addition, one must be able to accurately predict the amount of gas generation by burning of the exposed surface area at any given point in time for proper modeling.
3. Solution to the Problem
The solution to the problem is to rapidly ignite the entire outer surface of the propellant charge by wrapping the ignition cord around the propellant charge in order to produce a burn that is reproducible, and can be accurately modeled to predict the resulting conditions in the well and surrounding strata during the fracturing process.

Propellant Fracturing & Stimulation, LLC


A batteryless tire inflation pressure detecting apparatus includes, on the body of a vehicle, antennas and a transmitter transmitting radio waves through the antennas. The apparatus also includes, on each wheel of the vehicle, a pressure sensor sensing the pressure of a tire, a transceiver, and a charging unit powering the pressure sensor and the transceiver. The charging unit is charged with electric power induced by a corresponding one of the radio waves received by the transceiver. The apparatus further includes, on the body of the vehicle, a receiver receiving pressure signals transmitted by the transceivers, a pressure determiner determining the pressures of the tires based on the pressure signals, and a controller. To minimize influence of the radio waves on neighboring devices, the controller controls the transmitter so that least two of the radio waves are transmitted at different times, or at the same with a phase difference therebetween.

1. Technical Field of the Invention
The present invention relates generally to tire inflation pressure detecting apparatuses and wireless electric power charging systems. More particularly, the invention relates to a batteryless, direct-type tire inflation pressure detecting apparatus for a vehicle which is based on a transponder method and has minimum influence on electric or electronic devices provided on the vehicle.
2. Description of the Related Art
A conventional direct-type tire inflation pressure detecting apparatus includes at least a transmitter and a receiver.
The transmitter is directly installed to a wheel of a vehicle and includes a pressure sensor working to sense inflation pressure of a tire fitted on the wheel. The transmitter is configured to transmit a pressure signal indicative of the inflation pressure of the tire sensed by the pressure sensor.
The receiver is installed to the body of the vehicle and includes an antenna. The receiver is configured to receive, through the antenna, the pressure signal transmitted by the transmitter and determine the inflation pressure of the tire based on the received pressure signal.
In the above arrangement, the transmitter is conventionally supplied with electric power by a battery provided on the wheel of the vehicle. On the other hand, developments have recently been made to supply electric power to the transmitter without using a battery.
For example, U.S. Patent Application Publication No. 2005-0280523 discloses a batteryless tire inflation, pressure detecting apparatus which is based on a transponder method.
According to the transponder method, the receiver (i.e., the interrogator) works to transmit, through the antenna thereof, a radio wave for electric power charge to the transmitter, thereby charging a charging unit of the transmitter (i.e., the transponder) with electric power. When the charging unit is completely charged with electric power, the transmitter is then activated by the charged electric power to transmit the pressure signal to the receiver.
However, in such a batteryless tire inflation pressure detecting apparatus, the radio wave for electric power charge is generally transmitted at a high strength close to the upper limit of a permissible strength range specified under regulations.
Further, such a batteryless tire inflation pressure detecting apparatus generally includes more than one transmitter, and thus the receiver transmits more than one radio wave for respectively charging the charging units of the transmitters.
Accordingly, when the radio waves for electric power charge reach and intersect in an area where automotive electric or electronic devices, such as a radio, an ECU, and a keyless entry system, are provided, they may produce strong noises that influence those devices. Particularly, when the radio waves for electric power charge are transmitted at a frequency in the LF band, the influence thereof on the automotive devices may be very large.

Batteryless tire inflation pressure detecting apparatus having minimum influence on environment


An electricity distribution system such as a power strip that has adjustable outlets. The adjustable outlets have no fixed position within a housing. The power strip comprises a power cord/cable that is adapted to receive an input of electricity. One end of the power cord/cable may be terminated with an electrical connector. The opposite end of the power cord/cable is connected to a bus system which may be mounted inside of a housing. The system further includes at least one other power cord/cable that is connected to the bus system. As a result, each additional power cord/cable is adapted to be in electrical communication with the power cord/cable that is adapted to receive the input of electricity. Each of the additional power cord(s)/cable(s) may also be terminated with an electrical connector. In this manner, the present invention may provide at least one adjustable power outlet.

The present invention relates generally to an electricity distribution system and, more particularly, to an electrical strip such as a power strip. The present invention will be described primarily with regard to a power strip. However, the present invention may also be implemented in other types of electricity distribution systems such as for data transmission, address transmission, control signal transmission, response signal transmission, timing signal transmission, and other suitable uses.
Power strips are commonly used to distribute a power input to multiple outlets, i.e., jacks, sockets, or female connectors. An example of a typical power strip is comprised of a power cord having one end that is fitted with electrical plug, i.e., male connector, and another end that is connected to a plastic housing having a fixed shape. A plurality of outlets, e.g., five outlets, are positioned a fixed (and typically close) distance apart on a surface of the plastic housing. The power cord is connected to each of the outlets. As a result, power can be supplied to each of the outlets by inserting the electrical plug into a source of electricity, e.g., an 120 VAC outlet.
Power strips are commonly used in households, work environments, and in various other types of environments. In particular, power strips are useful when there are not enough built-in power outlets nearby to support all of the devices and equipment that need power. For example, power strips are commonly used in households to supply power to items such as televisions, stereos, compact disk (CD) players, lights, lamps, cable boxes, computers, computer monitors, computer printers, alarm clocks, sweepers, and other various types of household items.
Known power strips, however, have shortcomings which limit their effectiveness. As noted above, the outlets of known power strips are mounted a fixed distance apart in the plastic housing. This can lead to some different problems. First of all, the outlets may be positioned too closely together such that they cannot simultaneously reach all of the items that need power. The outlets may also be positioned too closely together such that electrical plugs cannot be simultaneously positioned in adjacent outlets. This occurs because plugs come in a large variety of shapes and sizes. As a result, bulky plugs and plugs that have a certain shape or orientation may prevent another plug from being inserted into an adjacent outlet of the power strip. Furthermore, even if it is possible to simultaneously position a plug in each of the outlets, it may be difficult to grasp and remove one of the plugs if the outlets are positioned too closely together. Accordingly, a need exists for an improved electricity distribution system that overcomes some or all of the aforementioned shortcomings.
The present invention provides an electricity distribution system that has adjustable outlets. The outlets can be moved in any direction with respect to each other and/or the housing to provide more convenient access to the outlets. One exemplary embodiment of the present invention is a power strip that has adjustable outlets. For example, a power cord or cable is provided that is adapted to receive an input of electricity. One end of the power cord or cable may be terminated with an electrical connector for receiving the input of electricity. The opposite end of the power cord or cable is connected to a bus system which may be mounted inside of a housing. The system further includes at least one other power cord or cable that is connected to the bus system. As a result, each additional power cord or cable is adapted to be in electrical communication with the power cord that is adapted to receive the input of electricity. Each of the additional power cord(s) or cable(s) may be terminated with an electrical connector. In this manner, the present invention may provide at least one adjustable power outlet.


A recording apparatus includes: a container; a conveying mechanism configured to convey a recording medium contained in the container; a recording head configured to record an image on the recording medium that has been conveyed through a conveying path by the conveying mechanism; a moving mechanism including a carriage and configured to move the carriage reciprocatingly together with the recording head; a first sensor installed in the carriage and configured to detect the recording medium; a second sensor configured to detect a change of a state of the container; a storage unit configured to store width information of the recording medium that is conveyed by the conveying mechanism; and a controller configured to control the conveying mechanism, the moving mechanism, and the recording head.

1. Field of the Invention
The present invention relates to a recording apparatus which records an image on a recording medium.
2. Description of the Related Art
In Japanese Patent No. 4062428, an ink-jet recording apparatus, which detects a width of a recording paper for each recording paper at the time of recording an image on the recording paper, has been described. In the ink-jet recording apparatus described, at the time of carrying out a first main scanning operation of a recording head, two end portions of the recording paper are detected by a sensor, and the width of the recording paper is acquired. Since the width of the recording paper is acquired for each recording paper, it is possible to maintain an image quality.


A hearing aid includes a faceplate (2) and a matching adaptor plate (4) below it. These plates are held in together by fasteners such as clips or screws (12). The faceplate and adaptor plate are custom cut and trimmed to seamless match a custom shell (9). Only the adaptor plate (4) is glued to the shell (9). A boundary (5b) between the faceplate (2) and the adaptor (4) is not visible on the hearing aid when worn by a user. Furthermore, the position of boundary B enables a reduction in the visible surface area of the faceplate (2) to be achieved.

The present invention relates to hearing aids and, in particular, to an xe2x80x9cin the earxe2x80x9d (ITE) hearing aid.
ITE (In The Ear) hearing aids appeared in the early 1970""s, and have become the most popular type of hearing aid currently used. Depending on the space occupied by the hearing aid, ITE hearing aids have been further categorised as Completely-In-Canal (CIC), In-The-Canal ITC), Half Concha (ITE) and Full Concha (ITE). The term ITE as used herein applies to all these categories of hearing aids.
The internal components of ITE hearing aids are generally housed in earshells which are custom made to fit the intended wearer""s ear. Components which make up the hearing aid, such as the battery holder, contacts, microphone, amplifier, switches and other user controls are built in a cluster on a plastic plate which is commonly called a faceplate. An earshell custom made to fit each individual ear is made in accordance with an impression made of the ear. The faceplate is trimmed to match the earshell. With the earphone mounted in the shell, the trimmed faceplate is bonded to the custom earshell with a solvent glue or adhesive. This form of construction is often referred to as a custom ITE.
Alternatively, the bulk of the components can be built in the form of a module. The module generally fits into an adaptor plate and is removably held onto the adaptor plate by fasteners such as screws or clips. The adaptor plate is then glued to the customised earshell, and trimmed to physically match the custom shell. The most common form of this construction is often referred to as semi-modular. This term is used because the earphone is generally mounted in the shell by means of an output tube which is glued to the shell at the shell tip. When the module is unfastened from the adaptor, the earphone wiring is still connecting the module and the custom earshell.
Custom ITE hearing aids are often difficult and time consuming to repair, as the faceplate must be removed from the earshell to allow access to the components. Modular or semi-modular ITE hearing aids are easier to repair than custom hearing aids, as the module on which the components are mounted is easier to remove and replace. However, the smallest possible size of the module dictates the size of the outer surface of the hearing aid, as the adaptor used to attach the module to the earshell must not be cut too close to the join between the adaptor and the module. Further, this join is usually cosmetically unappealing. It is not practical to add any desired additional components on the aid even though the shell opening may be sufficiently larger than the module to accommodate such components.
It is an object of the present invention to overcome or substantially ameliorate at least some of the above disadvantages.
The present invention in one broad form provides an in-ear type hearing aid comprising:
a shell for placement in an ear, said shell comprising an outer opening, said shell being adapted to house electrical components therein;
a top plate having an outer periphery; and
a bottom plate having an outer periphery and an opening, said bottom plate being fixed to said shell over said opening in said shell, said top plate being removably attached to said bottom plate, wherein the outer periphery of said top plate substantially corresponds in size and shape to the outer periphery of said bottom plate.
Preferably, at least some of said electrical components are mounted on said top plate and extend into the shell through said opening in said bottom plate. Examples of these electrical components include a battery, microphone, and amplifier, but may also include components such as a volume control, on/off switch, telecoil selector, program selector etc.
Preferably, said bottom plate is glued, adhered by means of a solvent, or fused onto the shell around its outer periphery.
Preferably, said top plate is releasably attached to the bottom plate by means of one or more screws.
Preferably, the outer peripheries of said bottom plate and said top plate correspond in size and shape to said outer opening in said shell.
The present invention in another broad form provides a method of assembling a hearing aid, said method comprising the steps of:
providing a shell for placement at least partly within an ear, said shell comprising an outer opening;
providing a bottom plate at least as large as the outer opening in said shell, said bottom plate comprising an opening;
providing a top plate at least as large as the outer opening in said shell;
releasably mounting said top plate on said bottom plate;
fixing said bottom plate onto said shell over said outer opening; and
trimming the outer peripheries of said top plate and said bottom plate to substantially the same size and shape.
Preferably, the bottom plate and top plate are trimmed to substantially the same size and shape as the outer opening in said shell.
Preferably, said method further comprises the step of mounting one or more electrical components onto said top plate, said electrical components extending into said shell through said opening in said bottom plate.
The present invention in another broad form provides, in combination:
a top plate removably mounted on a bottom plate, said bottom plate adapted to be fixed onto a shell of an in-the-ear type hearing aid over an outer opening in said shell, said bottom plate having an opening therein, wherein the outer peripheries of said top plate and said bottom plate are substantially the same shape and size.
Preferably, one or more electrical components are mounted on said top plate and extend into said shell through said opening in said bottom plate.


A formation fluid sample is exposed to a rigidly-supported semi-permeable membrane such as silicone rubber to permit diffusion of gases and vapors from the formation fluid into a vacuum chamber, while at the same time, blocking the passage of any liquids. The membrane-transmitted gas is analyzed in the vacuum chamber by a residual gas analyzer. An ion pump or sorbent is associated with the evacuated chamber to maintain the vacuum. The ion pump or sorbent removes gases and vapors from the chamber that diffuse into the chamber from the reservoir sample that is on the opposite side of the semi-permeable membrane.

1. Field of the Invention
The present invention relates generally to downhole reservoir characterization and in particular to a method and apparatus for real time identification of gases diffused out of a formation fluid sample. Formation fluid samples are obtained and gases are allowed to diffuse from these fluid samples through a semi-permeable membrane into an evacuated chamber. The gases are analyzed in the evacuated chamber by a mass spectrometer or residual gas analyzer (RGA) and a processor which identifies and distinguishes between gases such as C1–C5, H2S, C02, N2 and other gases or vapors present in a downhole reservoir fluid sample.
2. Summary of the Related Art
To obtain hydrocarbons such as oil and gas, boreholes are drilled into the earth by rotating a drill bit attached at to the end of a drill string. Modern directional drilling systems generally employ a drill string having a bottom hole assembly (BHA) and a drill bit at an end thereof that is rotated by a drill motor (mud motor) and/or by rotating the drill string. A number of downhole devices placed in close proximity to the drill bit measure certain downhole operating parameters associated with the drill string. Such devices typically include sensors for measuring downhole temperature and pressure, azimuth and inclination measuring devices and a resistivity-measuring device to determine the presence of hydrocarbons and water. Additional downhole instruments, known as logging-while-drilling (LWD) tools, are frequently attached to the drill string to determine the formation geology and formation fluid conditions during the drilling operations.
Commercial development of hydrocarbon fields requires significant amounts of capital. Before field development begins, operators desire to have as much data as possible regarding the nature of the hydrocarbon formation, in order to evaluate the reservoir for commercial viability. Despite the advances in data acquisition during drilling using the MWD systems and wire line analysis applications, it is often necessary to conduct further testing of the hydrocarbon reservoirs in order to obtain additional data. Therefore, after the well has been drilled, the hydrocarbon zones are often tested with other test equipment such as wire line tools, which are used to further analyze and monitor the formation.
One type of post-drilling test involves producing fluid from the reservoir and collecting such fluid samples downhole in tanks for transport to surface laboratories where Pressure-Volume-Temperature (PVT) studies and fluid properties such as density, viscosity and composition are measured. Also, one can measure the downhole fluid pressure at several depths and, from this pressure gradient, calculate the fluid's density.
Fluid samples extracted downhole are typically analyzed weeks to months later in a surface laboratory to identify and quantify gases present in the fluid. It is time consuming to retrieve fluid samples downhole and send them to a surface lab for analysis of gas content Moreover, surface analysis requires removal of the fluid sample and the tool from the borehole for testing the sample before additional exploration and/or production activities occur. Thus, there is a need for a real-time downhole method and apparatus for detection, distinction and quantification of gases in the formation.

Method and apparatus for downhole fluid analysis for reservoir fluid characterization


Writing in each sector of a series of sectors of a recording medium in which data is to be written caused by a single data write request location information which is information indicating a location of the sector in the series of sectors and common information which varies every time data writing to the series of sectors occurs and is information set relating to the series of sectors.

The present invention relates to a method for writing data, a method for data validation, a method for computer control, a computer, a disk array unit, and a disk drive.
It is conventionally known as a method for detecting error of data stored in a recording medium such as CD-ROM, DVD-ROM, and the like, to use EDC (Error Detection Code). Also, it is known to detect error by comparing a expected value address computed from address information of a sector and a sector number read out from the sector.
However, these conventional error detection methods were not sufficient as a mechanism for detecting data write omission in sector unit, for example, when data writing to a recording medium has not been performed normally due to a head voltage shortage at writing or dust on the recording medium.

Method and apparatus for writing data and validating data in a recording medium


Variable-displacement, single-acting vane pumps in which the cylindrical cam member is adjustably supported within an outer annular cam housing to enable the cam member to be adjustably-rotated relative to the housing to adjust the geometric center of the cam chamber relative to the center of the rotor member and thereby adjust the displacement capacity of the pump between zero-flow maximum flow values. The annular housing for the cam member comprises a roller bearing assembly between its inner race surface and the cylindrical outer surface of the cam member, which minimizes the friction when the cam member is rotated during adjustment and enables the adjustment to be actuated remotely, such as by means of a small motor gear assembly.

1. Field of the Invention
The present invention relates to single acting, variable displacement fluid pressure vane pumps, such as for aircraft use, incorporating means for balancing cam bearing load, minimizing clocking forces, reducing friction and actuation loads.
Over the years, the standard of the commercial aviation gas turbine industry for main engine fuel pumps has been a single element, pressure-loaded, involute gear stage charged with a centrifugal boost stage. Such gear pumps are simple and extremely durable, although heavy and inefficient. However, such gear pumps are fixed displacement pumps which deliver uniform amounts of fluid, such as fuel, under all operating conditions. Certain operating conditions require different volumes of liquid, and it is desirable and/or necessary to vary the liquid supply, by means such as bypass systems which can cause overheating of the fuel or hydraulic fluid and which require heat transfer cooling components that add to the cost and the weight of the system.
2. State of the Art
Vane pumps and system have been developed in order to overcome some of the deficiencies of gear pumps, and reference is made to the following U.S. patents for their disclosures of several such pumps and systems: U.S. Pat. Nos. 4,247,263; 4,354,809; 4,529,361 and 4,711,619. Reference is also made to copending application Ser. No. 08/114,253, filed Aug. 30, 1993, the disclosure of which is hereby incorporated herein.
Vane pumps comprise a rotor element machined with slots supporting radially-movable vane elements, mounted within a cam member and manifold having fluid inlet and outlet ports in the cam surface through which the fluid is fed to the low pressure inlet areas or buckets of the rotor surface for rotation, compression and discharge from the high pressure outlet areas or buckets of the rotor surface as pressurized fluid.
Vane pumps that are required to operate at high speeds and pressures preferably employ hydrostatically (pressure balanced) vanes for minimizing frictional wear. Such pumps may also include rounded vane tips to reduce vane-to-cam surface stresses. Examples of vane pumps having pressure-balanced vanes which are also adapted to provide undervane pumping, may be found in the aforementioned copending application and in U.S. Pat. Nos. 3,711,227 and 4,354,809. The latter patent discloses a vane pump incorporating undervane pumping wherein the vanes are hydraulically balanced in not only the inlet and discharge areas but also in the seal arcs whereby the resultant pressure forces on a vane cannot displace it from engagement with a seal arc.
Variable displacement vane pumps contain a cam element which is adjustable relative to the rotor element, about a pivot point which is external to the cam chamber, in order to change the relative volumes of the inlet and outlet or discharge buckets and thereby vary the displacement capacity of the pump.
Among the problems encountered with single acting vane pumps with external cam adjustment pivots are the high actuation loads required to overcome the high friction cam sealing loads in order to move the cam member relative to the seals to adjust the displacement. Also, the external pivot support of the cam member results in high clocking loads or stresses on the cam member due to the differential bucket pressures on the externally-supported cam member.

Variable displacement vane pump adjustable by low actuation loads


A thumb drive has an on-board memory for storing digital information, a male USB connector coupled to the on-board memory for connecting to a USB port of a computer appliance, and an extension/retraction mechanism coupled to the connector and on-board memory for extending the connector from an enclosure of the drive and for retracting the connector when not in use. In various embodiments a light is also provided for use with finding female USB ports for connection, and as a utility light.

In the computer arts there continues to be motivation for increased density and ease-of-use in mass storage devices. A solid state device known now in the art as a thumb drive was relatively recently introduced advancing the standard for both density and ease-of-use, and such hot-plug drives are made by several manufacturers. A common feature of thumb drives as known in the art is a male USB connector, and functionality to hot-plug and remove, that is, without turning off the computer to which the drive is connected and disconnected. Another common feature is a plastic protective cover for the male USB connector.
Although the advance in the mass storage art with the advent of thumb drives is dramatic, there are still some problems with such a system. For example, the plastic covers for use on the male USB connectors are not very secure, and tend to come loose and be lost. As a remedy, many manufacturers provide two and sometimes three plastic covers with each device sold, often with different colors. Still another problem is that USB ports on computers are not universally easily visible and accessible. Some such ports are on the back of tower cases which are often placed under desks or other furniture, so finding an unused USB female port for connecting the male USB connector of a thumb drive is often not trivial. When a female port is out of sight or in a darkened area, the connection must often be made by feel alone. Still further, when the thumb drive is connected to a computer, the plastic protective cover is removed, and is easily misplaced.
There are also other functions that may be accomplished with the considerable memory available with thumb drives, and their relatively easy connectivity to personal computers and other computerized appliances. One such function is as an MP3 player, to download MP3 files, such as music files, from a computerized appliance, and an ability to play these files into an ear piece, headphone or amplifier from the thumb drive.
Therefore what is clearly needed is a way to dispense with the plastic covers and still protect the male USB connector for thumb drives, a way to aid in the search for unused USB ports, and aid in the engagement of the male USB connector of the thumb drive with the female port on the computer, and a way to use the thumb drive as an MP3 player.

Thumb drive with retractable USB connector


A crystal substrate and a crystal film of a III-V compound of the nitride system which have no defects in the surfaces. A method of manufacturing a crystal of a III-V compound of the nitride system, and a method of manufacturing a device. A base crystal layer is formed over a basal body. After etching the base crystal layer using a first mask pattern, an intermediate crystal layer is formed. After etching the intermediate crystal layer using a second mask pattern, a top crystal layer is formed. The crystal growth of the intermediate crystal layer starts at the walls of grooves formed by etching in the base crystal layer. This reduces the possibility that dislocations develop into the intermediate crystal layer. No dislocations occurring above the first mask pattern propagate through the top crystal layer since the dislocations are removed by etching using the second mask pattern.

1. Field of the Invention
The invention relates to a method of manufacturing a device such as a semiconductor laser device. The invention also relates to a crystal substrate of a III-V compound of the nitride system and a crystal film of a III-V compound of the nitride system, which are used for the method of manufacturing a device. The invention also relates to a method of manufacturing a crystal of a III-V compound of the nitride system, which is used for manufacturing the crystal substrate or the crystal film.
2. Description of the Related Art
In general, the manufacturing process of a device such as a semiconductor laser device or a light-emitting diode (LED) involves the deposition of semiconductor films or the like laid one upon another over the surface of a crystal substrate or a crystal film comprised of a III-V compound of the nitride system, e.g., gallium nitride (GaN). A desirable method to obtain a crystal substrate or a crystal film for the use in the manufacturing process is to form a bulk of a crystal of a III-V compound of the nitride system, but the manufacture of a bulk of a crystal of a III-V compound of the nitride system is difficult. Thus, it has been the practice to grow epitaxially a crystal of a III-V compound of the nitride system on a basal body made of sapphire (Al2O3).
However, the difference in the crystal structures of the basal body and the crystal formed thereon, or the small interaction between the basal body and the crystal formed thereon causes dislocations to occur from the interface. Such dislocations develop in the direction of crystal growth, piercing the crystal to reach its surface. This causes a problem that crystal substrates or crystal films thus grown have numerous defects in the surface.
To overcome the problem, Publication of Japanese Unexamined Patent Application No. Hei 10-312971 proposes a method in which a gallium nitride (GaN) base layer is formed over the surface of a sapphire (Al2O3) basal body, and a mask pattern made of silicon dioxide (SiO2) is formed over the base layer, and then a gallium nitride (GaN) crystal is grown over the base layer with the mask pattern in between. According to the method proposed, the development of dislocations is prevented by the mask pattern, resulting in a reduction in the number of dislocations piercing the crystal to reach its surface. The method, however, cannot sufficiently reduce the number of dislocations in crystal substrates or crystal films because some dislocations develop through windows of the mask pattern to pierce the crystal.
Thus, the above-noted Publication discloses another method in which two mask patterns are formed in the direction of the thickness of the crystal so that a dislocation developing through a window of one mask pattern is blocked by another mask pattern. This method, however, requires accurate alignment of two mask patterns in the direction of the thickness of the crystal so that one mask pattern is laid over the windows of another mask pattern, which causes a problem of difficult work.
According to Extended Abstracts (The 46th Spring Meeting, 1999); The Japan Society of Applied Physics and Related Societies, page 416, disclosed is a method in which a base layer made of gallium nitride (GaN) or the like is formed over a sapphire (Al2O3) basal body, and a recessed region is formed in the surface of the base layer, and a gallium nitride (GaN) crystal is grown over the surface of the base layer. Since the method causes a change in the direction of the development of dislocations at the recessed region of the base layer, the number of dislocations piercing the crystal reduces to some extent. In the method, however, dislocations propagate through the portion other than the recessed region of the base layer. Thus, the method has a problem that the number of dislocations piercing the crystal cannot be reduced sufficiently.
On the other hand, according to MRS Internet J. Nitride Semicond. Res. 4S1, G3. 38 (1999) and MRS Internet J. Nitride Semicond. Res. 4S1, G4. 9 (1999), proposed are methods of preventing dislocations piercing the crystal using lateral growth. In the former method, a groove is formed in a gallium nitride (GaN) crystal as a seed crystal, and the crystal growth is restarted in the lateral direction from the walls of the groove.
In the latter method, after a mask pattern is formed on the surface of a gallium nitride (GaN) crystal as a seed crystal, the gallium nitride (GaN) crystal is etched to form a groove, and the crystal growth is re-started in the lateral direction from the walls of the groove, while the mask pattern prevents the crystal growth over the surface of the seed crystal. However, with the former method, there is a possibility that dislocations will develop from the surface of the seed crystal. With the latter method, there is a possibility that other dislocations will develop above the mask pattern. Thus, both methods have a problem that defects in the surface of the crystal cannot be prevented sufficiently.

This patent is subject to a terminal disclaimer.

Method of manufacturing crystal of III-V compound of the nitride system, crystal substrate of III-V compound of the nitride system, crystal film of III-V compound of the nitride system, and method of manufacturing device


A ball valve apparatus 10 for clearing an obstruction in a conduit is disclosed. The ball valve apparatus 10 incorporates a wear resistant choke tube 42 in the downstream opening 40B of the ball 36. The choke tube 42 can be two to four times smaller than the opening 40A on the upstream side of the ball 36. Removal of catalyst through the choke tube results in lower velocity of the flow through the bore of the valve, thereby reducing wear and erosion. In normal operation in an FCC unit, catalyst is extracted from the system through the choke tube 42. When the conduit becomes plugged, the ball valve apparatus 10 can be cycled into a fully opened position, thereby creating a high flow rate of fluid through the conduit, removing any existing obstructions.

The present invention relates to a ball valve and method for dumping catalyst fines from a catalyst regenerator such as in the fluidized catalyst cracking (FCC) units of refineries.
In a refinery reactor operating at elevated temperatures and pressures, catalyst is used in the preparation of useable hydrocarbon molecules. Specifically, the catalyst helps to break down larger hydrocarbon molecules into smaller hydrocarbon molecules, thereby producing "lighter" hydrocarbons for further processing. Over time, catalyst in FCC units becomes coated with carbon (also known as coke) and ceases to efficiently break down the larger hydrocarbon molecules. The coked catalyst is transported to a regenerator reactor where it is heated with oxygen to burn off the coke and regenerate the catalyst. During normal operation and regeneration, some catalyst is broken into smaller particles, known as fines, and must be periodically replaced. A discharge piping system is used to dump the catalyst fines. The ball valve and method of the present invention can be used with such a piping system.
Extraction of catalyst fines has been performed using wear resistant choke tubes of a specific size selected to establish proper flow rates for the process requirements. The tube periodically plugs up with solids, requiring the line to be isolated and the tube removed and cleaned. Isolation is achieved by closing the upstream block valves, resulting in plant down time as well as added maintenance expenses.
An alternate approach has been to use a valve in place of the choke tube, and to throttle and control the flow of catalyst with the valve. This system has the advantage of having the capability for adjusting the flow, however the internals of the throttling valve wear rapidly and are expensive to replace.
Fisher (U.S. Pat. No. 3,386,461) discloses a multi-port orifice valve, adapted for cleaning of the bores of the valve, that uses interchangeable inserts which may be placed within the bore of the valve. The valve body features four apertures (two per side), positioned to allow servicing (cleaning of the bore as well as removal and reinsertion of orifice inserts) while the particular bore is in the closed position, without having to shut down the line and remove the valve.
Crawford (U.S. Pat. No. 3,707,161) discloses a ball valve wherein the ball has a removable insert threadedly engaged within the flow passage. Also disclosed is an alternate embodiment in which the opening for the inserted choke tube is adjustable, accomplished with a threaded stem located at the bottom of the valve body.
Kindersley (U.S. Pat. No. 3,985,150) discloses a valve assembly for use with abrasive fluids wherein the valve bore has an abrasion resistant insert. The inserts may comprise ceramics (aluminum oxide, silicon carbide, boron carbide), metals (chrome alloys), rubber, or synthetic plastics (urethanes). Throttling the valve is achieved by rotating the ball, producing a reduced bore opening.
Marandi (U.S. Pat. No. 5,937,890) discloses ball valve inserts for controlling fluid flow. The inserts are preferably parabolic (convex) in shape, corresponding to the shape of the ball, providing a substantially equal percentage flow characteristic between maximum and minimum flow rate conditions. The parabolic shape of the insert compensates for the arcuate or non-linear path traveled by the insert during throttling.
Green (U.S. patent application Ser. No. 10/352,329) discloses a ball valve adapted to receive threaded inserts which may be secured to the valve by various means, including a retaining ring, press fitting, gluing, soldering, or threads. The combination of the standard ball valve and the inserts provide an infinite range of valve flow coefficients that are lower than the valve's maximum rated flow coefficient, depending on the diameter of the orifice. A disclosed advantage is stated as being retrofittable, although this requires removing the valve, selecting and inserting the desired insert for a desired flow coefficient, and reinserting the valve in the line.
Scaramucci (U.S. Pat. No. 3,542,338) discloses a ball valve adapted for throttling having a bore treated or lined with an erosion resistant material. Scott (U.S. Pat. No. 3,794,071) discloses a brake control valve device, wherein the device is equipped with a choke. Berchem (U.S. Pat. No. 5,205,533) discloses a ball valve having a ceramic coated passage and a restriction within the ball, wherein the bore within the ball narrows, producing a larger outlet bore diameter than the inlet bore.
Booth et al. (U.S. Pat. No. 5,551,467) and Lester et al (U.S. Pat. No. 5,593,135) disclose ball valves for precise throttling of fluid through the valve, achieving near linear performance in controlling the flow of the fluid. Chowdhury (U.S. Pat. No. 6,260,820) discloses a valve and method for producing the valve. Hayduk (U.S. Pat. No. 6,412,756) discloses a gas tight ball valve for use with granular material.
Guerra (U.S. Pat. No. 6,540,206) discloses a bi-directional ball valve for use with cold gases, featuring a through hole on its side surface, which in the closed position is available for the passage of fluid. The hole appears to have a greatly reduced bore diameter as compared with the main flow path. Milberger et al. (U.S. patent application Ser. No. 10/137,219) disclose a ball valve for use in oil and gas production systems, having a vent bore for the venting of pressure.

Continuous catalyst extraction valve with line cleaning feature


A monopole antenna applicable especially to small mobile stations. In one embodiment, the radiator of the antenna is trough-like in shape so that it covers the head surface, front and rear surfaces and both side surfaces of the dielectric cover of the radio device at an end of the device. On the side of the side surfaces slots are formed in the radiator, starting from its edge, for increasing the electric size. The radiator is fed electromagnetically by a separate element which is shaped so that the antenna has at least two operating bands. The ground plane of the antenna is in one embodiment disposed apart from the radiator, thus not extending inside the ‘trough’.

1. Field of Invention
The invention relates generally to an antenna of a radio device, such as small-sized mobile wireless terminals, and particularly in one exemplary aspect to monopole antenna and related structures.
2. Description of Related Technology
In small-sized radio devices, such as mobile phones, the pursuit of space saving is a significant factor when designing a device. Regarding the antenna, using a dielectric substrate for the radiator, using a monopole radiator instead of PIFA (Planar Inverted-F Antenna), and the above-mentioned implementation of the radiator in the outer cover of the radio device are commonly used solutions which save space.
Making the radiator as a part of the device's outer cover is known. An example of such an arrangement is the solution for the antenna of a radio device shown in FIG. 1, known from the publication EP 1 439 603. Therein, a radio device can be seen from behind and its cross section at the antenna structure. The upper part 130 of the rear part of the device's outer cover is comprised of conductive material and functions as the radiator of the antenna. The radiator 130 joins the dielectric rest part 150 of the outer cover without discontinuity.
In the cross section shown in FIG. 1 there is seen the radiator 130, and below it the circuit board PCB of the device, on the upper surface of which board the ground plane GND of the antenna is located. Between the radiator and ground plane there is a conductive feed element 120 which is separated galvanically from the radiator by a distinct thin dielectric layer DIE. The radiator has no galvanic coupling to any conductive part of the radio device. Instead, the feed element 120 is coupled galvanically to the antenna port of the radio device by the feed conductor 116 and to the ground plane by the short-circuit conductor 115. An example of the shape of the feed element 120 is visible in the drawing of the radio device. It is a conductive strip comprising, as viewed from its short-circuit point SP, two arms with different lengths to implement two operating bands for the antenna. The longer arm of the feed element, the radiator 130, and the ground plane GND constitute a resonator, the natural frequency of which is in the lower operating band, and the shorter arm of the feed element, the radiator and the ground plane constitute a resonator, the natural frequency of which is in the higher operating band.
The use of the separate feed element is favourable, because in that case the placement of the antenna's operating bands and the matching of the antenna can be arranged without interfering with the shape of the radiator. However, a flaw of the solution in FIG. 1 is that good band characteristics and adequate efficiency require a remarkably long distance between the radiator and the ground plane GND. This again means that the need for antenna space is also in this case greater than desirable, thereby making the overall device size larger.
An object of the invention is to implement an antenna provided with a cover radiator in a new and advantageous way.
In one exemplary embodiment of the invention, radiator of an antenna is trough-like so that the head surface, front and rear surfaces and both side surfaces of the dielectric cover of a device are coated by it at an end of the radio device. On the side of the side surfaces there are slots in the radiator starting from its edge for increasing the electric size. The radiator is fed electromagnetically by a separate element which is shaped so that the antenna has at least two operating bands. The ground plane of the antenna is apart from the radiator, thus not extending inside the 'trough'.
An advantage of the invention is that the radiator of the exemplary antenna is short in the longitudinal direction of the radio device, and the space required by the antenna in the radio device is thus relatively small. This is due to the trough-like shape of the radiator and the slots on its sides. Thanks to the slots the radiator, which resonates at a certain frequency, becomes smaller. Also the monopole structure, or the location of the ground plane apart from the radiator, results in a smaller size of the radiator. Another advantage of the invention is that several resonances, which can be tuned separately, are provided for the antenna.
In another aspect of the invention, an antenna for use in a radio device is disclosed. In one embodiment, the antenna includes: a feed element having feed and short circuit points associated therewith, at least the short circuit point being in electrical communication with a ground plane of the radio device; and a device end cover, the end cover comprising a dielectric and having the feed element disposed on an interior surface thereof, and at least one conductive coating on an outer surface thereof, the at least one conductive coating forming at least part of a multiband radiator.
In another embodiment, the radio device has a head surface and first and second side surfaces, and the antenna comprises: a radiator having an antenna cover associated therewith, a feed element comprising an electromagnetic coupling to the radiator; and a ground plane in electrical communication with the radiator. In one variant, the antenna has at least a lower operating band and a higher operating band; the radiator is disposed substantially at an end of the radio device, and comprises a conductive coating of a dielectric cover of the radio device, the dielectric cover comprising a trough-like shape so that its bottom corresponds to the head surface of the radio device; the antenna cover is a part of the dielectric cover, and the radiator comprises a slot proximate at least one of the side surfaces and starting from an edge of the radiator and to decrease its physical size at the frequencies of the lower operating band of the antenna.
In a further aspect of the invention, a mobile wireless device is disclosed. In one embodiment, the device includes: a radio transmitter and receiver; a first device housing element; a circuit board disposed substantially with the first device cover, the circuit board comprising a ground plane; and a dielectric device end housing element comprising: a feed element having a short circuit point in communication with the ground plane, and a feed point coupled to the radio transmitter and receiver; and a slotted radiator formed on at least part of an exterior of the end housing element. The feed element, short circuit point, ground plane, and slotted radiator cooperate to provide the wireless device with multiband wireless capability.
In another aspect of the invention, a method of operating a wireless antenna is disclosed. In one embodiment, the antenna comprise a feed element with feed point, a short circuit point, a dielectric element, and a radiating element, and the method includes: feeding a signal to the feed element via the feed point; short circuiting the feed element to a ground plane via the short circuit point; and electromagnetically coupling at least portions of the feed element to the radiating element via the dielectric element, the coupling causing the radiator to radiate at least portions of the signal in at least one of an upper band and a lower band in which the antenna is capable of operating.
FIG. 1 was already described in connection with the description of prior art.
FIG. 2 shows an example of the radio device provided with an antenna according to one embodiment of the invention. The radio device RD is elongated and relatively flat so that it has two ends, head surfaces corresponding to these ends, front and rear surfaces, and first and second side surfaces. The antenna radiator is located at one end of the device which can be the end on the side of the device's speaker or the opposite end. In the figure is shown the outer cover of the device which comprises the main part COV of the cover and the antenna cover 332. In this example, the antenna cover is of conductive material, for which reason it functions as a part of the radiating structure. The radiator proper is disposed underneath it. Also, the main part COV of the cover is in this example of conductive material, for which reason there is a relatively narrow non-conductive part SPL of the outer cover between it and the antenna cover 332.
The antenna cover of the embodiment of FIG. 2 is trough-like by shape, opening naturally towards the middle part of the radio device. A slot, such as the first slot SL3, is formed on the side of the both side surfaces of the antenna cover, starting from its edge. These slots are discussed in greater detail below with respect to the description of FIG. 3.
FIG. 3 shows an example of the structure according to the invention. The antenna of the radio device presented in FIG. 2 is used as the example. The structure comprises dielectric cover 310, feed element 320, radiator 331 and the above-mentioned antenna cover 332. For the sake of clarity, the antenna cover has been drawn as separate in the figure; in the assembled device it is disposed over the other parts of the antenna structure.
The dielectric cover 310 forms the frame of the end of the radio device and, at the same time, the antenna frame. It is trough-like by shape so that it has a bottom, opposite short sides and opposite long sides. The bottom corresponds to the head surface of the whole device, the short sides correspond to the side surfaces of the whole device at the device's end in question, and the long sides correspond to the front and rear surfaces of the whole device at the device's end. On the outer surface of the dielectric cover 310 there is disposed the radiator 331. This has, in the illustrated embodiment, been implemented by metallizing the outer surface e.g. with the LDS method (Laser Directed Structuring). Therefore, the radiator is trough-like following by shape the head surface, the front and rear surfaces and the side surfaces of the radio device. The areas of the outer surface of the dielectric cover starting from the edges of its short sides are left without metallizing so that on the side of the side surfaces of the radio device, there are slots directed from the edge of the radiator towards its bottom. On the side of the first side surface there is the first slot SL1, and on the side of the second side surface there is the second slot SL2. These slots increase the electric size of the radiator. As a result, the resonance, which corresponds to the lowest operating band of the antenna, can advantageously be realized by means of a physically smaller radiator compared to a radiator without said slots.
The width of the radio device determines the length of the radiator, in which case the decrease in size means the shortening of the radiator in the longitudinal direction of the device, or in the depth direction of the radiator.
On the inner surface of the dielectric cover 310 there is disposed the feed element 320 of the radiator. In the illustrated example it extends in the depth direction from the open edge of the dielectric cover to the bottom surface of the cover. The feed element is connected to the transmitter and receiver of the radio device from its certain point FP, which is the feed point of the antenna. Only an electromagnetic coupling exists between the feed element and the radiator. The feed element is shaped so that it has several resonances together with the radiator and ground plane. The operating bands of the dualband antenna are based on these resonances. An example of the foregoing is shown in FIGS. 4 and 5. The feed element is connected also to the ground plane of the antenna from its short-circuit point SP.
In the finished structure, the antenna cover 332 is tightly placed on the radiator. If the antenna cover is formed of conductive material, as in this example, slots are needed on the side surfaces of the device in order to prevent the short-circuit of the slots SL1, SL2 of the radiator. The third slot SL3 in the antenna cover is formed at above-mentioned first slot SL1, and the fourth slot SL4 is formed at the second slot SL2. If the radio device has a steel cover, also the antenna cover is formed of steel for the sake of appearance. As a conductor, steel is clearly poorer than the metal which is used as the radiator 331. For this reason, an antenna cover made of steel has little significance as a radiator, although it in principle functions as a part of the radiating structure. The antenna cover can also be made of a non-conductive material, in which case it may lack the slots SL3 and SL4 seen in FIG. 3.
FIG. 4 shows an example of the feed element of an antenna according to one embodiment of the invention, as if spread on a plane. Also, the ground plane GND of the antenna is visible in the figure, and is located beside the feed element (and thus also the radiator 431 as viewed in the direction of the normal of the ground plane). The ground plane is in this embodiment parallel with the front and rear surface of the radio device.
The feed element 420 includes the short-circuit point SP and the feed point FP of the whole antenna, and it includes in the illustrated embodiment three parts. The first part 421 comprises six successive portions which form a simple spiral pattern: the first portion of the first part starts from the feed point FP and is directed away from the ground plane, that is, towards the bottom of the radiator. The second portion is parallel with the edge of the ground plane, or perpendicular to the first portion. The third portion is directed back towards the ground plane, the fourth portion towards the first portion, the fifth portion towards the second portion and the sixth portion towards the third portion. In the tail end TE of the sixth portion, there is an extension towards the second portion for strengthening the electromagnetic coupling between the tail end and the second portion.
The second part 422 of the feed element 420 is a mainly straight conductor strip between the ground plane GND and the spiral formed by the first part 421. The second part starts from the feed point FP, and ends at the point from which the feed element is connected to the ground plane, or the short-circuit point SP. In the example of FIG. 4, there is included a capacitive element C41 between the feed point and the starting end of the second part. By means of the capacitance, the antenna matching in the lower operating band is improved so that this band is widened.
The third part 423 of the feed element of the illustrated embodiment is a continuation of the second part from the short-circuit point SP forward. It has the same direction as the second part, and is open at its outer end.
The exemplary feed element 420 has three significant resonances together with the radiator and ground plane. The lowest frequency resonance, or the first resonance, is based on the electric length of the structure constituted by the first 421 and second 422 part of the feed element and the capacitive element between these parts. The higher frequency resonance, or the second resonance, is based on the electric length of the conductor constituted by the second 422 and third 423 part. It can be tuned by changing the physical length of the third part. The highest frequency resonance, or the third resonance, is a harmonic resonance of the first resonance. It can be tuned by changing the electromagnetic coupling between the second and sixth portions of the first part 421 by shaping the tail end TE of the sixth portion.
Also, a tuning element 440 is seen in FIG. 4. It is in one embodiment comprised of a conductor strip on the inner surface of the dielectric cover, connected to the ground plane from its one end. The tuning element is used to affect the resonance which the radiator has alone (naturally with the co-operation of the ground plane), which resonance is then the fourth significant resonance of the antenna to be considered. The tuning element can be located, in respect of the feed element, for example, on the opposite side of the trough formed by the dielectric cover.
FIG. 5 shows an example of the band characteristics of an exemplar, antenna configured according to the invention. The antenna used as the basis of FIG. 5 is comparable to that presented in the previous figures; the capacitance of the matching capacitor C41 between the feed point and second part of the feed element is 4.7 pF. The curve shows the fluctuation of the reflection coefficient S11 of the antenna as the function of frequency. The lower the reflection coefficient, the better the antenna has been matched. The feed element is shaped so that the antenna has two operating bands, the lower and higher one. The lower operating band is based on the above-mentioned first resonance r1, the frequency of which is about 0.9 GHz. It is seen from the curve that the lower operating band covers the frequency range 880-960 MHz (w1 in the figure) used by the EGSM system (Extended GSM), when the value −5 dB of the reflection coefficient is considered to be the criterion of the boundary frequency of the band. The higher operating band is based on the above-mentioned second, third and fourth resonance. The frequency of the second resonance r2 is about 1.75 GHz, the frequency of the third resonance r3 is about 2.1 GHz and the frequency of the fourth resonance r4 is about 2.0 GHz. It is seen from the curve that the higher operating band well covers the frequency range 1710-2170 MHz (w2 in the figure) used by the systems GSM 1800, GSM 1900 and WCDMA in all. The fourth resonance is tuned between the second and third resonances on the frequency scale, by which means the reflection coefficient can be kept low in the entire large operating band. Without the fourth resonance, the antenna matching would be poor in the middle range of the band.
FIG. 6 shows an example of the efficiency of an antenna in free space according to one embodiment of the invention. Curve 61 shows the fluctuation of the efficiency in the lower operating band. In the range w1, the efficiency fluctuates between −1 dB and −3 dB, being about −1.6 dB on average. Curve 62 shows the fluctuation of the efficiency in the higher operating band. In the range w2, the efficiency fluctuates between −0.5 dB and −3.7 dB, being about −2.4 dB on average. The values of the efficiency are accordingly quite good.
An adjustable antenna according to the invention has been described above. In details, its structure can naturally differ from what is presented. For example, the shape of the feed element of the antenna can vary widely. The resonance frequencies of the antenna can be arranged also so that the number of the operating bands is more than two. The feed element can also be located on the surface of a separate thin and flexible dielectric plate which is fastened on the surface of the antenna frame. The antenna frame again can be, besides the same as the dielectric cover of the antenna, also a separate dielectric object to be placed inside the dielectric cover. The tuning element affecting the resonance frequency of the radiator can be located at different places in the antenna structure. The inventive idea can be applied in different ways within the scope of the invention as set forth in the various exemplary embodiments and disclosure provided herein.


The present disclosure relates, according to some embodiments, to fluid pump apparatuses. A fluid pump apparatus may comprise a suction compensator, a housing compensator, and a pump. A suction compensator may comprise an ambient fluid compensator, an ambient fluid bladder, and a spring compensator, wherein the spring compensator comprises a first separator partitioning an internal volume of the spring compensator into a first suction fluid chamber and a compensation fluid chamber. A housing compensator may comprise a second separator partitioning an internal volume of the housing compensator into a second suction fluid chamber and a lubrication fluid chamber. The compensation fluid chamber may be in fluid communication with the suction compensator. The first suction fluid chamber may be in fluid communication with the second suction fluid chamber. A pump may comprise a housing defining a lubrication fluid compartment in fluid communication with the lubrication fluid chamber.

Pressure changes as a function of seawater depth (approximately 1 bar per 10 meters), temperature, and salinity. For example, fluids and equipment (e.g., tanks, pumps) lowered from the surface to a depth of 10,000 feet would experience a substantial increase in pressure. In addition, pressure changes in a fluid volume may occur when equipment (e.g., pumps) operates. Subsea installation an operation of subsea fluid systems may be encumbered by such pressure changes.

Subsea pressure compensating pump apparatus