There is provided a corona generating device for a printing machine, including a conductor; a frame for supporting the conductor; a cleaning assembly, within the frame, for cleaning the conductor, the cleaning assembly includes a cleaning carriage, a drive system for translating the cleaning carriage along the length of the conductor in a path of movement, the cleaning assembly further includes a cleaning pad, means for engaging a portion of the clean pad into contact with conductor, and means for translating the cleaning pad from an used portion to an unused portion of the cleaning pad.

This invention relates generally to a corona generating device, and more particularly concerns a method and apparatus for cleaning the electrode element on a corona generating device.
In a typical electrophotographic printing process, a photoconductive member is charged to a substantially uniform potential so as to sensitize the surface thereof. The charged portion of the photoconductive member is exposed to a light image of an original document being reproduced. Exposure of the charged photoconductive member selectively dissipates the charges thereon in the irradiated areas. This records an electrostatic latent image on the photoconductive member corresponding to the informational areas contained within the original document. After the electrostatic latent image is recorded on the photoconductive member, the latent image is developed by bringing a developer material into contact therewith.
Generally, the developer material comprises toner particles adhering triboelectrically to carrier granules. The toner particles are attracted from the carrier granules to the latent image forming a toner powder image on the photoconductive member. The toner powder image is then transferred from the photoconductive member to a copy sheet. The toner particles are heated to permanently affix the powder image to the copy sheet. In printing machines such as those described above, corona devices perform a variety of other functions in the printing process.
For example, corona devices aid the transfer of the developed toner image from a photoconductive member to a transfer member. Likewise, corona devices aid the conditioning of the photoconductive member prior to, during, and after deposition of developer material thereon to improve the quality of the electrophotographic copy produced thereby. Both direct current (DC) and alternating current (AC) type corona devices are used to perform these functions. One form of a corona charging device comprises a corona electrode in the form of an elongated wire connected to a high voltage AC/DC power supply. Alternatively, a charging device may comprise an array of pins integrally formed from a sheet metal member.
The scorotron is similar to the pin corotron, but is additionally provided with a screen or control grid disposed between the coronode and the photoconductive member. The screen is held at a lower potential approximating the charge level to be placed on the photoconductive member. The scorotron provides for more uniform charging and prevents overcharging.
A problem with electrophotographic printing process is the accumulation of silica and other contamination on the corona wire. These accumulations are adhered onto the corona wire due to the high voltage placed on the corona wire during operation. These accumulations can deteriorate the image quality and can interrupt the continuous use of these printers by causing print defects, such as dark streaks on the printed pages. For some cases, these defects could be cured by simply wiping the contamination from the small thin corona wire.
Manual or automatic cleaners are routinely employed to remove silica and other materials from corotron wires to prolong the generation of strong, uniform corona. Automatic cleaners are generally more effective than manual cleaners because the cleaning schedule can be more tightly controlled. Because the same part of the cleaning pad always cleans the same part of the wire or grid, in some cases the cleaner removes contamination in long strips along the wire, while leaving adjacent strips uncleaned.
The present disclosure obviates the problems noted above by replacing the stationary grid pad holder with a rotating holder. In ordinary operation of the cleaning cycle actuates the rotation so that a different part of the cleaning pads engages the wire or grid with each cleaning cycle. These several configurations clean the wire more thoroughly over the course of several cleaning cycles, resulting in improved print quality and extended life.
There is provided a corona generating device for a printing machine, including a conductor; a frame for supporting said conductor; a cleaning assembly, within said frame, for cleaning said conductor, said cleaning assembly includes a cleaning carriage, a drive system for translating said cleaning carriage along the length of said conductor in a path of movement, said cleaning assembly further includes a cleaning pad, means for engaging a portion of said clean pad into contact with conductor, and means for translating said cleaning pad from an used portion to an unused portion of said cleaning pad.
While the present disclosure will be described in connection with a preferred embodiment thereof, it will be understood that it is not intended to limit the disclosure to that embodiment. On the contrary, it is intended to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the disclosure as defined by the appended claims.
For a general understanding of the features of the present disclosure, reference is made to the drawings. In the drawings, like reference numerals have been used throughout to identify identical elements.
FIG. 1 schematically depicts an electrophotographic printing machine incorporating the features of the present disclosure therein. It will become evident from the following discussion that the present invention may be employed in a wide variety of devices and is not specifically limited in its application to the particular embodiment depicted herein.
Referring to FIG. 1 of the drawings, an original document is positioned in a document handler 27 on a raster input scanner (RIS) indicated generally by reference numeral 28. The RIS contains document illumination lamps, optics, a mechanical scanning drive and a charge coupled device (CCD) array. The RIS captures the entire original document and converts it to a series of raster scan lines. This information is transmitted to an electronic subsystem (ESS) which controls a raster output scanner (ROS) described below. FIG. 1 schematically illustrates an electrophotographic printing machine which generally employs a photoconductive belt 10. Preferably, the photoconductive belt 10 is made from a photoconductive material coated on a ground layer, which, in turn, is coated on an anti-curl backing layer. Photoconductive belt 10 moves in the direction of arrow 13 to advance successive portions sequentially through the various processing stations disposed about the path of movement thereof. Photoconductive belt 10 is entrained about stripping roller 14, tensioning roller 20 and drive roller 16. As drive roller 16 rotates, it advances photoconductive belt 10 in the direction of arrow 13. Initially, a portion of the photoconductive surface passes through charging station A.
At charging station A, a corona generating device indicated generally by the reference numeral 22 charges the photoconductive belt 10 to a relatively high, substantially uniform potential. At an exposure station, B, a controller or electronic subsystem (ESS), indicated generally by reference numeral 29, receives the image signals representing the desired output image and processes these signals to convert them to a continuous tone or grayscale rendition of the image which is transmitted to a modulated output generator, for example the raster output scanner (ROS), indicated generally by reference numeral 30. Preferably, ESS 29 is a self-contained, dedicated minicomputer. The image signals transmitted to ESS 29 may originate from a RIS as described above or from a computer, thereby enabling the electrophotographic printing machine to serve as a remotely located printer for one or more computers. Alternatively, the printer may serve as a dedicated printer for a high-speed computer. The signals from ESS 29, corresponding to the continuous tone image desired to be reproduced by the printing machine, are transmitted to ROS 30. ROS 30 includes a laser with rotating polygon mirror blocks.
The ROS will expose the photoconductive belt to record an electrostatic latent image thereon corresponding to the continuous tone image received from ESS 29. As an alternative, ROS 30 may employ a linear array of light emitting diodes (LEDs) arranged to illuminate the charged portion of photoconductive belt 10 on a raster-by-raster basis. After the electrostatic latent image has been recorded on photoconductive surface 12, belt 10 advances the latent image to a development station, C, where toner, in the form of liquid or dry particles, is electrostatically attracted to the latent image using commonly known techniques.
The latent image attracts toner particles from the carrier granules forming a toner powder image thereon. As successive electrostatic latent images are developed, toner particles are depleted from the developer material. A toner particle dispenser, indicated generally by the reference numeral 39, dispenses toner particles into developer housing 40 of developer unit 38.
With continued reference to FIG. 1, after the electrostatic latent image is developed, the toner powder image present on photoconductive belt 10 advances to transfer station D. A print sheet 48 is advanced to the transfer station, D, by a sheet feeding apparatus, 50. Preferably, sheet feeding apparatus 50 includes a nudger roll 51 which feeds the uppermost sheet of stack 54 to nip 55 formed by feed roll 52 and retard roll 53. Feed roll 52 rotates to advance the sheet from stack 54 into vertical transport 56.
Vertical transport 56 directs the advancing sheet 48 of support material into the registration transport 120, past image transfer station D to receive an image from photoreceptor belt 10 in a timed sequence so that the toner powder image formed thereon contacts the advancing sheet 48 at transfer station D. Transfer station D includes a corona generating device 58 which sprays ions onto the back side of sheet 48. This attracts the toner powder image from photoconductive surface 12 to sheet 48. The sheet is then detacked from the photoreceptor by corona generating device 59 which sprays oppositely charged ions onto the back side of sheet 48 to assist in removing the sheet from the photoreceptor. After transfer, sheet 48 continues to move in the direction of arrow 60 by way of belt transport 62 which advances sheet 48 to fusing station F.
Fusing station F includes a fuser assembly indicated generally by the reference numeral 70 which permanently affixes the transferred toner powder image to the copy sheet. Preferably, fuser assembly 70 includes a heated fuser roller 72 and a pressure roller 74 with the powder image on the copy sheet contacting fuser roller 72. The pressure roller is cammed against the fuser roller 72 to provide the necessary pressure to fix the toner powder image to the copy sheet. The fuser roller is internally heated by a quartz lamp (not shown). Release agent, stored in a reservoir (not shown), is pumped to a metering roll (not shown). A trim blade (not shown) trims off the excess release agent. The release agent transfers to a donor roll (not shown) and then to the fuser roller 72. The sheet then passes through fuser assembly 70 where the image is permanently fixed or fused to the sheet. After passing through fuser 70, a gate 80 either allows the sheet to move directly via output 16 to a finisher or stacker, or deflects the sheet into the duplex path 100, specifically, first into single sheet inverter 82 here. That is, if the sheet is either a simplex sheet, or a completed duplex sheet having both side one and side two images formed thereon, the sheet will be conveyed via gate 80 directly to output 84.
However, if the sheet is being duplexed and is then only printed with a side one image, the gate 80 will be positioned to deflect that sheet into the inverter 82 and into the duplex path 100, where that sheet will be inverted and then fed to acceleration nip 102 and belt transports 110, for recirculation back through transfer station D and fuser 70 for receiving and permanently fixing the side two image to the backside of that duplex sheet, before it exits via exit path 84. After the print sheet is separated from photoconductive surface 12 of photoconductive belt 10, the residual toner/developer and paper fiber particles adhering to photoconductive surface 12 are removed therefrom at cleaning station E.
Cleaning station E includes a rotatably mounted fibrous brush in contact with photoconductive surface 12 to disturb and remove paper fibers and a cleaning blade to remove the nontransferred toner particles. The blade may be configured in either a wiper or doctor position depending on the application. Subsequent to cleaning, a discharge lamp (not shown) floods photoconductive surface 12 with light to dissipate any residual electrostatic charge remaining thereon prior to the charging thereof for the next successive imaging cycle.
The various machine functions are regulated by controller 29. The controller is preferably a programmable microprocessor which controls all of the machine functions hereinbefore described. The controller 29 provides a comparison count of the copy sheets, the number of documents being recirculated, the number of copy sheets selected by the operator, time delays, jam corrections, etc. The control of all of the exemplary systems heretofore described may be accomplished by conventional control switch inputs from the printing machine consoles selected by the operator. Conventional sheet path sensors or switches may be utilized to keep track of the position of the document and the copy sheets.
Turning next to FIG. 2, focusing on the cleaning device of the present disclosure, as illustrated the grid 310 is installed in the frame 304. Frame 304 has a groove which supports grid 310 therein. Wire 312 are positioned below grid 310. The charging devices include end blocks, which support wire 312. The cleaning device of the present disclosure employs annular cleaning pads for the grid and the grid side of the wire. Both cleaning pads are mounted on a circular base with a mechanism to rotate the base a fraction of a turn each time the cleaner returns to the home position. For example design rotates the pads by 45° with each cleaning cycle. In this case, the wire and grid are each effectively cleaned by eight different cleaning pads. If each of the eight orientations cleans a few strips of the wire or grid, the various strips will overlap so that over time, the entire wire or grid will be cleaned thoroughly.
Cleaning device 315 is driven along the inner portion of charging device by a lead screw 314 being rotated by motor 400. Cleaning device 315 has a scrub pad 330 on the top surface thereof for cleaning any particles (ie toner or debris) adhering to grid 310 as the cleaning device moves along the charging device. Wire cleaning pads remove any particles (ie silica or debris) adhering to wire 312 as the cleaning carriage moves along the charging device.
Turning next to FIGS. 3, 4 and 5, as illustrated in FIG. 3 is a view of cleaner assembly facing the home position. Cleaner assembly includes ratchet wheel 352 that has wire cleaning pad 354 on a bottom surface thereof and grid cleaning pad 330 on a top surface thereof. Ratchet wheel 352 is rotatably mounted thereto to support member 357. Support member 357 has aperture 358 defined therein wherein wire 312 passes there through. Wire pad holder 353 holds wire pad 356 and is adapted to move from an unengaged position to an engaged position. In the engaged position wire pad 356 contacts wire 312 and moves wire 312 into contact with wire cleaning pad 354.
Protrusion 311 at the home position (shown in FIG. 2) acts to retract the wire pad holder 353 away from the wire, disengaging the wire from both wire pads in the same operation. A protrusion 311 pushes against the ratchet wheel 352 and advance it one notch. This protrusion will deform toward the left as the next tooth from ratchet wheel 352 comes into position, until it springs back into place, preventing the wheel from turning backward. Ratchet wheel 352 has eight teeth which indexes wire pad into eight cleaning pad areas. The number of teeth on ratchet wheel 352 or number of cleaning pad areas could be different; however it is preferred to use as many teeth as is practical on ratchet wheel 352 or cleaning pad areas.
FIG. 4 illustrates a view of cleaner assembly from below, showing detail of the teeth on ratchet wheel 352 and the wire cleaning pad 354. Also in view are the supports 360 and 361 built into the holder base which prevent ratchet wheel 352 from wobbling and bias it against the grid. The dimensions of the support arms are chosen to deflect with an appropriate spring force when the ratchet wheel 352 is pressed away from the grid 315. Snap feature 390 on top portion of support member 357 (as shown in FIGS. 5 and 7) is shaped to allow clearance for the wire when not engaged with wire pad 356, and how the ratchet wheel rests on the support arms 360 and 361.
FIG. 5 illustrates a view of cleaner assembly illustrating the approximate path of the wire through the assembly. Note how the wire clears the snap feature 365 due to the way the annular wire pad 356 presses against it. When the wire pad holder retracts in home position, the wire will rest lower clearing the snap feature even more.
Having in mind the construction and the arrangement of the principal elements thereof, it is believed that a complete understanding may now be had from a description of its operation. During cleaning the cleaner of the present disclosure operates much like a conventional cleaner. As the cleaner approaches the home position, protrusion 311 on the insulator disengage the wire pad holder 353 from the wire, then advance the ratchet wheel 352 one notch. As the ratchet wheel 352 turns, the upper ratchet 380 (as shown in FIG. 6) pushes grid cleaning pad 330 away from the grid, to which the support arms comply. Shortly before the protrusion from the insulator snaps to the next tooth on the ratchet wheel 352, the snap feature 390 snaps to the next tooth on the upper ratchet 380 (as shown in FIG. 6), holding the ratchet wheel in place as it moves away from the protrusion during the next cleaning cycle. Over the course of eight cleaning cycles, eight different parts of cleaning pad 354.engage the wire, so the wire is cleaned thoroughly. One part of the wire pad will clean sections of the wire that other parts of the cleaning pad 354 may have missed. Also, the grid pad or brush presses on the grid from eight different directions and in eight configurations relative to the grid. All of this is accomplished using the same number of parts as a conventional cleaner, so that the cost of the assembly is nearly equal to that of a conventional cleaner. With the extended life enabled by more thorough cleaning, the overall run cost is decreased. A more thorough cleaning also improves charge uniformity, resulting in improved customer satisfaction with print quality. The concept may be readily extended to a two wire corotron. The only notable changes would be that the annular wire pad would be of a diameter to simultaneously engage both wires, and the wire pad holder and holder base would be reconfigured to allow for a center shield. In this case the bases of the two halves of the snap feature would be on opposite sides of the center shield.
It is, therefore, apparent that there has been provided a cleaning device in accordance with the present invention fully satisfies the aims and advantages hereinbefore set forth.
While this invention has been described in conjunction with a specific embodiment thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.
It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. Unless specifically recited in a claim, steps or components of claims should not be implied or imported from the specification or any other claims as to any particular order, number, position, size, shape, angle, color, or material.


A magnetic head in a magnetic storage system is provided in which materials that do not individually display high permeability and low coercivity are satisfactorily employed in a write head when coupled to adjacent high permeability layers. The magnetic head includes a gap layer which separates a pair of poles. At least one pole of the pair of poles includes a pole layer formed of a high permeability material and a seed layer adjacent to the pole layer. The seed layer is formed of a high moment low permeability material having a high saturation magnetic moment greater than 2.1 Tesla and a low permeability of about 10-100. The high permeability material of the pole layer causes the permeability of the adjacent seed layer to substantially increase from about 10-100 to about 1400-1600, thereby providing a pole with high permeability and high saturation moment. In addition, a method of forming a magnetic head for use in a magnetic storage system is provided.

The present invention relates to magnetic data storage systems. In particular, the invention relates to a magnetic write head pole (writer pole) used in such systems.
Magnetic heads mounted on a magnetic disc drive are required to provide larger magnetic fields with higher gradient for magnetic recording at higher density. More recent magnetic heads combine both a magnetoresistive (MR) or giant magnetoresistive (GMR) element for reading information from a magnetic medium and an inductive element for writing information to such a magnetic medium. Such magnetic heads are typically referred to as composite thin film magnetic heads or merged MR heads. The magnetic head is mounted or embedded in a slider which is supported in transducing relationship with respect to a magnetic medium.
The inductive write head element includes first and second poles which have first and second pole tips respectively. The pole tips are separated by a gap at an air bearing surface (ABS) or head surface. A coil is positioned between the first and second poles. Information is written on the magnetic medium at the first and second pole tips.
Flux density, which is a measure of the quantity of magnetism, needs to be high in the inductive head element for it to provide a high magnetic field for writing. There are limitations to the capability of the inductive head element to provide high flux density since materials have a saturation level beyond which they will conduct no more flux. Similarly, magnetic moment, which is a measure of the strength of the magnet, does not change beyond a certain level (reaches saturation) even if the strength of the applied magnetic field is increased. A high saturation magnetic moment is very desirable for write heads recording at high areal densities, the areal density being the amount of data that can be squeezed on to a given area of the magnetic medium. Further, finite element modeling or analysis of magnetic recording indicates that a high saturation magnetic moment is particularly critical for those magnetic layers adjacent to the non-magnetic gap layer of the write head.
The use of materials with high magnetic moment for writer pole tips allows for the generation of higher magnetic fields in the magnetic media, larger field gradients, and faster effective rise times. Improvements, such as narrower pulse widths, smaller erase bands, and straighter transitions for given media properties are possible if materials with high magnetic moment are used for the poles. In addition, increased over-write (OVW) on magnetic media having high coercivity can also be achieved with high moment poles. OVW, expressed in dB, is a measure of how well prior recorded information can be erased by over writing the medium with a different signal. All the above advantages become even more important at high areal densities of magnetic recording.
The prior art teaches that in order to practically achieve a higher field in the gap, a seed and/or capping layer can be used adjacent to the gap to minimize saturation of pole tips and produce a higher gap field. Further, the prior art suggests that all of the individual magnetic layers utilized in the write head should possess high magnetic permeability and moderately soft magnetic properties in addition to a desirable saturation magnetic moment. Prior art write heads have employed individual layers of magnetic materials that each possess a combination of the above desirable properties, thereby limiting the choice of the saturation magnetic moment level to materials that have high magnetic permeability and moderately soft magnetic properties.
The present invention addresses these problems, and offers other advantages over the prior art.
The present invention relates to data storage systems that include a magnetic head with at least one pole having a seed layer made of a material with a low permeability by itself and a high saturation moment magnetically coupled to an adjacent high permeability layer which causes the permeability of the seed layer material to increase, thereby addressing the above-identified problems.
A magnetic head in a magnetic storage system is provided in which materials that do not individually display high permeability and low coercivity are satisfactorily employed in a write head when coupled to adjacent high permeability layers. The magnetic write head includes a gap layer which separates a pair of poles. At least one pole of the pair of poles includes a pole layer formed of a high permeability material and a seed layer adjacent to the pole layer. The seed layer is formed of a high moment low permeability material having a high saturation magnetic moment greater than about 2.1 Tesla and a low permeability of about 10-100. The high permeability material of the pole layer causes the permeability of the adjacent seed layer to substantially increase from about 10-100 to about 1400-1600, thereby providing a pole with high permeability and high saturation moment. In addition, a method of forming a magnetic head for use in a magnetic storage system is provided.

Writer pole employing a high saturation moment, low permeability layer adjacent to writer gap


A device for plucking dead hairs from the skin of a dog includes a handle part for handling the device, a stem part connected to the handle part, on the end of which stem part is a comb part for guiding the hairs of the dog into the device, a base on the stem part, onto which base hairs are guided by means of the comb part, a gripping part that is on the stem part and is moveable along a predetermined trajectory, which gripping part in a part of its trajectory moves in the direction of the base and presses against the base, in which case the hairs of the dog are between the base and the gripping part, and in which case by means of the movement of the gripping part a pulling motion is exerted on the hairs that are between the gripping part and the base.

Coarse-haired dog breeds are trimmed to typify their breed by plucking. The purpose of trimming is to remove dead hair that has stopped growing, so that new hair can grow in its place. At the same time it enhances the wellbeing and health of the dog as well as shaping it to look like that breed.
If the dead hair is not removed in time, many layers of different-aged hairs grow in the coat, of which some detach when trimming and some do not. When all the dead hairs can be plucked from a dog in one session, the new covering of fur becomes tidy and even.
Plucking generally occurs with one's fingers or using a dull trimming knife. The purpose is to remove the hair whole, including the root, and not to cut it. Plucking always occurs in the direction that the hair grows.
Known in the art are some publications relating to the subject. For example, publication GB 190207469 A presents a device for removing coarse dog hair. The device includes brushes having the purpose of raising the coarse hair up from the undercoat and guiding it between two blades. The device is complex and there is reason to doubt its operability.
Publication JP 2010187543 A presents in particular a device intended for the epilation of coarse-haired dogs, wherein the gripping of the hair to be plucked and the detaching of the hair is arranged with two rotating wheels facing each other. The front part of the device has an aperture via which the hairs are pulled inside. The length of the hair to be detached is selected by adjusting the distance of the wheels from the aperture. Suction and a collection container are also attached to the device. The device is not presented as being for use in the removal of loose hairs. However, it has been observed that the plucking that occurs between the rolls operates poorly.
Publication U.S. Pat. No. 3,613,690 A presents a means/knife, with which coarse hairs can be plucked. This is thus utilized, as described earlier, in the manual method.
Publication JP 11276009 A presents a device with which the hairs being shed from the coat of a cat or dog can be removed, i.e. the device is aimed at the removal of the loose hairs of a smooth-haired animal. The device includes two brushes rotating in opposite directions for gripping the hairs and a suction means can be connected to the device for collecting the hairs.
Publication JP 2001120098 A presents a device for brushing and cleaning the coat of an animal. The device includes a belt onto which a brush-like surface is arranged, and which belt is arranged to travel while supported on rolls. Suction is connected to the device, for removing hairs and other debris.
Publication U.S. Pat. No. 5,207,183 A presents a device for removing fleas and other debris from the coat of a dog. In the device is a belt arranged to travel while supported on rolls, the surface of which belt has been made to be such that it collects fleas and other such debris from the coat. The device also includes a brush for brushing the coat. The device is not, however, intended for the removal of hair.
It can be deduced from the state of the art that up until now it has not been possible to develop a device with which dead hair could be removed from the coat of a coarse-haired dog, but instead plucking takes place, even today, manually. It is time-consuming and even causes skin problems on the hands. Brushes intended for collecting the loose hair of a smooth-haired dog are not suited for plucking the dead hair that is still attached in the coat of a coarse-haired dog.
It is also not possible to use corresponding technology, as e.g. in an epilator designed for people, in plucking the hairs of a coarse-haired dog. An epilator tears all the hair out and cannot differentiate between living and dead hair. An epilator-type device is also not suited for long hair (human hair is short). Dog hair requires a long straight-line pulling motion and effective removal of hair from the blades. A round roller of the epilator type clogs immediately.

Device for plucking dead hairs from the skin of a dog


A new system has a plurality of modular segments flexibly attached to one other and a source of electrical power and plating and coating solutions at the rear of the plurality of modular segments. The plurality of modular segments include a drive stage configured to push the plurality of modular segments along a surface, a plating stage configured to apply the plating solution to the surface under a pre-set operating current density to deposit metal or metal alloy onto the surface, a surface treatment application stage configured to apply the coating solution to the surface, and a curing stage configured to cure the coating solution to form a final coating on the surface that is resistant to corrosion, chemical attacks and chemical buildup.

Brush plating and spray coating are traditionally used to apply coatings to metallic surfaces. Coating large interior surfaces with these techniques is difficult due to the restricted space and limited access, and the durability and applicability of the coatings themselves may be compromised or inherently limited. Reaching interior surfaces such as pipeline interiors is difficult, but can be done with pig-like vehicles equipped with sprayers. However, these vehicles only apply a spray-on coating. In a corrosive environment, typical spray-on coatings are subject to failure should any one spot or area of pipe surface become exposed. Corrosion and/or buildup may occur in that one spot and then expand and fail entire areas of coating.
Needs exist for improved systems and methods for coating, treating and/or reconditioning interior or other difficult to reach surfaces.

Interior plating and automated surface-deposition system


A seat base is interposed between a supporting surface, such as the sling-type seat of a wheelchair, and a cushion or even the user, it having a lower contour which generally matches the contour of the supporting surface and a upper contour which provides a comfortable seating surface or gives a desired shape to an overlying cushion. The lower contour is established by a plurality of transversely directed ribs, whereas the upper contour is established by transversely directed panels located between the ribs. The polymer material from which the seat base is formed has uniform thickness and as a consequence the ribs create grooves that open out of the upper surface to separate the panels.

This invention relates in general to seating and, more particularly, to a device for providing a seating surface with a desired contour and to a seating arrangement formed with the device.
The typical wheelchair has side frames which move together to enable the chair to be reduced to a more compact configuration--one suitable for storage or transport. To accommodate this conversion, the typical wheelchair has attached to its side frames a sling-type seat, which being flexible, simply folds upon itself as the side frames move together. While the sling-type seat nicely facilitates the conversion between open and closed positions, it does not serve the occupant's needs in other more important respects. Such seats become uncomfortable after prolonged periods, and much worse, concentrate the occupant's weight at the bony protuberances of the buttocks, thus inducing decubitus ulcers, more commonly known as bed sores.
The problem resides primarily in the inherent curvature of the sling-type seat--a generally uniform curvature which resembles that of a hammock. It tends to urge the occupant's thighs together, making them difficult to spread, particularly for one so crippled as to be confined to the wheelchair. While the seat has flexibility, it has little resiliency in the vertical direction and as a consequence most of the occupant's weight is transferred to the seat in the region of the bony protuberances of the buttocks. Without the circulation induced by movement, decubitus ulcers may well develop in the region of the bony protuberances.
Cellular cushions, such as those disclosed in U.S. Pat. Nos. 4,005,236 and 4,541,136 of R. H. Graebe, substantially reduce the incidence of decubitus ulcers from wheelchair occupancy. These cushions interpose a multitude of air cells between the sling-type seat and the buttocks of the occupant, and these air cells deflect to accommodate the contour of the occupant's body. Since the air cells are interconnected, each cell exerts essentially the same restoring force on the body irrespective of the magnitude of its deflection. Thus, the region of the bony protuberances in the buttocks floats and bears no greater weight than other areas of the buttocks, and decubitus ulcers are less likely to develop.
Nevertheless, a flotation-type cellular cushion having a flexible backing and air cells of low height to a measure tends to assume the contour of the support on which it rests. Such a cellular cushion, when placed on a sling-type wheelchair seat, might not distribute the suspension forces well enough to overcome the curvature of the seat and as a consequence the cushion may confine the occupant laterally to an excessive measure, thus forcing the occupant's thighs together in an uncomfortable manner.
The present invention resides in a light weight base or tray having generally uniform thickness throughout, insofar as the material from which it is formed is concerned, yet having ribs which impart rigidity and the desired lower contour to it. The upper surface, on the other hand, possesses a contour suitable for seating, particularly as an underlying support for a cushion, since it enhances the effective depth of immersion in the buttocks area.


A system and method supporting the advertising of extended network access to multimedia services via a broadband access gateway is disclosed. A representative embodiment of the present invention may comprise a wireless interface and may be capable of exchanging multimedia communication between the wireless interface and a broadband network. The gateway may determine available media-related services, and may transmit information about those services to an access device that may comprise, for example, a mobile multimedia handset, a personal digital assistant, and a personal computer. The access device may notify a user of the availability of the media-related services using visual and/or audible means. The gateway may receive from the access device capability and/or subscriber related information, and the gateway may transmit service information based upon the capability and/or subscriber-related information.

One major common problem faced by cellular and landline service providers is market competition. In today's climate of competitive markets, cellular service providers have found that one way for them to grow market share and defend their businesses is to be proactive and form alliances, and to partner with landline service providers. In addition, cellular service providers seek to differentiate their service offerings, and to capture the largest portion of market revenue by meeting an ever increasing demand for access to a wide range of media forms such as MP3 encoded audio, still and video imaging, data, instant messaging, and email. In a similar manner, the landline service providers have found that to grow market share and ward off competition, they too must be proactive and form alliances, and to partner with cellular service providers. Support for broad economical access to these converging forms of communication is needed to enable unfettered market growth, and to support the development and use of new handheld devices needed to provide increasing levels of mobile multimedia communication functionality.
Although the formation of alliances and partnerships between cellular service providers and landline service providers may help to ward off competition, such alliances and partnerships are faced with other problems. For example, the erection of cellular infrastructure such as cellular towers may be an expensive venture since this may require acquisition of real estate, whether in the form of outright purchases or through leasing. Cellular infrastructure also requires the establishment of one or more expensive backbone links to handle core network traffic. Another cellular-related problem is that the cellular signals do not penetrate and propagate in buildings such as homes and offices very well. This is especially true with the frequencies that are typically utilized in the United States, which may vary between 800 MHz and 1900 MHz or 1.9 GHz.
At the current time, a user of a wireless mobile device such as, for example, a WiFi-equipped PDA, a Bluetooth-equipped cellular phone, or a WiFi-equipped laptop that wishes to access wide area networks such as the Internet must actively seek information via personal acquaintances, websites and printed materials to determine the locations of wireless access points for their use. For example, many fast-food restaurants and up-scale coffee shops currently provide WiFi Internet access, but provide little or no indication on the premises that such services are available. Potential users of communications services, in particular those unfamiliar with an area such as tourists and business travelers, are left unaware of the existence of such points of access, and the services that may be available. They may pass through areas having such coverage while they are, in fact, in need of access to communication facilities. On the other hand, those that operate such areas of wireless service coverage have few tools available to notify users of wireless-enabled devices of the availability and particulars of services that may be accessible. In addition, no efficient means exists to offer access to a variety of media services, or to know whether any potential users of such services are with range of the access points through which they might be made available.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.

Method and system for extended network access services advertising via a broadband access gateway


Novel bacteriophages of Bacillus anthracis, the nucleic acids of its genome, nucleic acids comprising nucleotide sequences of open reading frames (ORFs) of its genome, and polypeptides encoded by the nucleic acids, are described. Therapeutic and diagnostic compositions, methods and kits related thereto are also provided.

Anthrax is a disease is believed to be caused by the spore-forming bacterium, Bacillus anthracis, a bacterium that is readily found in soil. B. anthracis is believed to primarily cause disease in plant-eating animals. Though infrequent, when humans do become infected, they usually acquire the bacterium from contact with infected animals, animal hides or hair, or animal feces. The human disease has a relatively short incubation period (less than a week) and usually progresses rapidly to a fatal outcome.
In humans, anthrax may occur in three different forms: coetaneous anthrax, gastrointestinal anthrax and inhalation anthrax. Coetaneous anthrax, the most common form in humans, is usually acquired when the bacterium, or spores of the bacterium, enter the body through an abrasion or cut on the skin. The bacteria multiply at the site of the abrasion, cause a local edema, and a series of skin lesions—papule, vesicle, pustule and necrotic ulcer—are sequentially produced. Lymph nodes nearby the site are eventually infected by the bacteria and, in cases where the organisms then enter the bloodstream (20% of cases), the disease is often fatal. Gastrointestinal anthrax is caused by eating contaminated meat. Initial symptoms include nausea, vomiting and fever. Later, infected individuals present with abdominal pain, severe diarrhea and vomiting of blood. This type of anthrax is fatal in 25% to 60% of cases. Inhalation anthrax (also called woolsorters' disease) is acquired through inhalation of the bacteria or spores. Initial symptoms are similar to those of a common cold. Symptoms then worsen and these individuals present with high fever, chest pain and breathing problems. The infection normally progresses systemically and produces a hemorrhagic pathology. Inhalation anthrax is fatal in almost 100% of cases.
Coetaneous anthrax is acquired via injured skin or membranes, entry sites where the spore germinate into vegetative cells. Proliferation of vegetative cells results in gelatinous edema. Alternatively, inhalation of the spores results in high fever and chest pain. Both types may be fatal unless the invasive aspect of the infection may be intercepted.
B. anthracis is believed to possess two major virulence components. The first virulence component is a polysaccharide capsule which contains poly-D-glutamate polypeptide. The poly-D-glutamate capsule is not itself toxic but plays an important role in protecting the bacterium against anti-bacterial components of serum and phagocytic engulfment. As the B. anthracis bacterium multiplies in the host, it produces a secreted toxin which is the second virulence component of the organism. This anthrax toxin mediates symptoms of the disease in humans.
The anthrax toxin is believed to comprise three distinct proteins encoded by the bacterium: protective antigen (PA), lethal factor (LF) and edema factor (EF). PA is the component of the anthrax toxin that is believed to bind to host cells using an unidentified cell-surface receptor. Once it binds to cell surfaces, EF or LF may subsequently interact with the bound PA. The complexes are then internalized by the host cell with significant effects. EF is an adenylate cyclase which causes deregulation of cellular physiology, resulting in edema. LF is a metalloprotease that cleaves specific signal transduction molecules within the cell (MAP kinase isoforms), causing deregulation of said pathways, and cell death. Injection of PA, LF or EF alone, or LF in combination with EF, into experimental animals produces no effects. However, injection of PA plus EF produces edema. Injection of PA plus LF is lethal, as is injection of PA plus EF plus LF.
As an acute, febrile disease of virtually all warm-blooded animals, including man, anthrax can be used in biological weapons (BW). For example, ten grams of anthrax spore may kill as many people as a ton of the chemical warfare agent, sarin. Terrorists have included dry spores in letters. Biological weapons of mass destruction have been developed that contain large quantities of anthrax spores for release over enemy territory. Once released, spores may contaminate a wide geographical area, infecting nearly all susceptible mammals. Due to the spore's resistance to heat and dry conditions, contaminated land may remain a danger for years. In view of the serious threat posed by the disease, effective diagnostic tools are needed to assist in prevention and control of natural and man-made outbreaks. Due to the highly lethal nature of anthrax and BW agents in general, there is great need for the development of sensitive and rapid BW agent detection. Current detection technology for biological warfare agents have traditionally relied on time-consuming laboratory analysis or onset of illness among people exposed to the BW agent.
One promising approach to the detection and treatment of B. anthracis is the use of bacteriophage lysins as bacteriolytic agents. Bacteriophages specific for B. anthracis and related B. cereus bacteria strains may be isolated and used to detect and treat these bacteria. Bacteriophages near B. anthracis spores during spore germination may be used to infect and lyse the bacteria. A variety of phage-based bacterial therapies have been reviewed. D. H. Duckworth, P. A. Gulig, "Bacteriophages: Potential treatment for bacterial infections," BioDrugs, 16(1), 57-62 (2002). There are various environmental bacteriophages present in soils that may infect and lyse B. anthracis under controlled conditions. H. W. Ackermann, et al., "New Bacillus bacteriophage species," Archives of virology, 135(3-4), 333-344 (1994); H. W. Ackerman, M. S. Dubrow, Viruses of prokaryotes: General properties of bacteriophages, Boca Raton, Fla., CRC Press, Inc. (1989);
A bacterial lysin called PlyG, from bacteriophage-γ of B. anthraci, has been shown to lyse vegetative B. anthracis cells and is useful in promising methods for treatment of anthrax. R. Schuch, D. Nelson, V. Fischetti, "A bacteriolytic agent that detects and kills Bacillus anthracis," Nature 418, 884-889 (2002), incorporated herein by reference. A nucleotide sequence encoding PlyG is disclosed in GenBank accession #AF536823 and has a molecular mass of about 27,000. PlyG has been shown to control anthrax disease in mice, and to bind to vegetative cells. However, PlyG has no means to replicate itself in the presence of host bacteria. Methods and composition for the treatment of a variety of bacterial infections using a phage associated lytic enzyme specific for the invasive bacteria and an appropriate carrier for delivering the lytic enzyme into a patient are discussed in the following U.S. patents issued to Fischetti et al.: U.S. Pat. Nos. 5,604,109; 5,985,271; 6,056,954; 6,056,955 6,248,324; 6,254,866; and 6,264,945, all incorporated herein by reference. Effective treatment of 14 of 24 virulent B. anthracis strains by phage based methods has been reported in a preliminary study done at Johns Hopkins University Applied Physics Laboratory. Michael Walter, Ph.D., "Efficacy and Durability of Bacilus anthracis Bacteriophages Used Against Spores," Journal of Environmental Health, July/August 2003, 9-15.
Bacteriophages for B. anthracis may be isolated from the environment. For instance, Walter et al. report the isolation of Phages Nk, DB and MH for B. anthracis in topsoil. Walter, M H, Baker, D D, "Three Bacillus anthracis bacteriophages from topsoil," Curr Microbiol. 2003 July; 47(1): 55-58. Further bacteriophages useful for detection and treatment of B. anthracis are reported herein. The W and γ environmental bacteriophages of B. anthracis have been identified in topsoil, but the isolation of the polynucleotide and the identification of open reading frames coding for various polypeptides therein were unknown. E. W. McCloy, "Studies of a lysogenic Bacillus strain. I. A bacteriophage specific for Bacillus anthracis," Journal of Hygiene, 49(1), 114-125 (1951); E. R. Brown, W. B. Cherry, "Specific identification of Bacillus anthracis by means of a variant bacteriophage," Journal of Infectious Diseases, 96(1), 34-39 (1955).
The direct introduction of bacteriophages into an animal to prevent or fight diseases has certain drawbacks. Specifically, both the bacteria and the phage have to be in the correct and synchronized growth cycles for the phage to attach. Additionally, there are preferably the right number of phages to attach to the bacteria; if there are too many or too few phages, there will be either no attachment or no production of the lysing enzyme. The phage is preferably active enough to be effective. The phages may also be inhibited by many things including bacterial debris from the organism it is going to attack. Further complicating the direct use of a bacteriophage to treat bacterial infections is the possibility of immunological reactions within the subject being treated, potentially rendering the phage non-functional. The ability of bacteriophages to lyse and kill target bacterial may also be decreased by sunlight, UV light, desiccation or other conditions encountered during storage or use of a phage-containing therapeutic agent. Therefore, the potential effectiveness of any given bacteriophage against a target bacteria depends on the conditions under which the phage is deployed against the target bacteria. Studying the structure of phages and their efficacy against target bacteria in various conditions are useful in developing therapeutic methods for treating and preventing disease caused by target bacteria. Investigations of the structure and function of phages may also relate to diagnostic methods for detecting target bacteria and spores, such as those of B. anthracis. Many environmental conditions that may alter the effectiveness of a phage, such as phage W and phage-γ, against a B. anthracis or related target bacteria. The isolation and analysis of the phage polynucleotide sequences, and associated polypeptide sequences, of these and other phages are needed to relate to effective methods for prevention, treatment and diagnosis of B. anthracis bacteria and spores.

Lytic enzymes and spore surface antigen for detection and treatment of


The disclosure relates to antiviral therapeutic methods and related compositions. In certain embodiments, the disclosure relates to methods of treating or preventing a viral infection by administering a pharmaceutical composition comprising a TLR5 ligand, such as a flagellin, to a subject in need thereof.

The World Health Organization estimates that AIDS has killed more than 25 million people since it was first recognized. In 2007 there were 2.7 million new HIV infections and 2 million HIV-related deaths. Many chronic infections are retroviruses. Anti-retroviral drugs are medications for the treatment of infection by retroviruses such as HIV. When several agents are taken in combination, the approach is known as highly active antiretroviral therapy (HAART). HAART can have serious side-effects. Regimens can be complicated, requiring patients to take several pills at various times during the day. If patients miss doses, drug resistance can develop. Therefore, there remains a need for improved antiviral therapies. In particular, there remains a need for antiviral therapies with reduced toxicity and improved efficacy over existing treatments.
For certain chronic viral infections, the immune system cannot clear the virus from the host even with the aid of therapeutic agents. For example, although HAAT may improve symptoms associated with infection, there is currently no cure for HIV. Toll-like receptors (TLRs) play a role in the pathogenesis of multiple diseases involving both the innate and adaptive immune systems. TLRs in humans recognize different microbial ligands during infection. There are several protein kinases downstream of these adapters, notably the IL-1 receptor-associated kinase (IRAK) family and TBK-1. These activate pathways leading to the activation of the respective transcription factors nuclear factor kappaB (NFκB) and interferon regulatory factor 3 (IRF3), which in turn induce various immune and inflammatory genes.
TLR5 is the receptor for bacterial flagellin monomers. The region of flagellin that TLR5 recognizes is conserved among microbial species and therefore allows TLR5 to detect a wide variety of microbes. TLR5 signals by recruiting the TIR adapter MyD88, leading to the activation of the IKK complex and subsequent activation of the transcription factor NFκB. The activation of TLR5 has been recently reported to be an efficient adjuvant for influenza A vaccines. See, e.g., U.S. Published Patent Application No. 2005/0147627 (flagellin contemplated in vaccine adjuvant). Studies indicate that activating the TLR5 signaling pathway may have other therapeutic applications, not only in its role as a linker adjuvant candidate for vaccines, but also as a dampener of excessive apoptosis in acute radiation syndromes, a characteristic that may be extended for use in degenerative diseases and ischemia reperfusion injury. See, e.g., U.S. Pat. No. 7,638,485. It has been suggested that systemic administration of flagellin may protect against chemicals, bacteria, viruses, and radiation. Vijay-Kumar et al., J Immunol. 2008, 180(12):8280-5. It has also been identified that flagellin reactivates gene expression in certain viruses. See, e.g., Gargano et al., J Virol, (2009), 83(3):1474-82 and Thibault et al., Virology (2009) 389 (1-2): 20-5.

TLR5 ligands, therapeutic methods, and compositions related thereto


Apparatus for cleaning long tubular instruments including an ultrasonically agitated sump containing cleaning solution into which the instrument to be cleaned is placed. A pump and filter arrangement is connected to an end of the instrument to impose a pulsating partial vacuum thereon and draw cleaning fluid through the full length of the instrument. The filtered cleaning solution is then returned to the sump.

1.) Field of the Invention
This invention relates to cleaning of tubular medical instruments such as endoscopic biopsy forceps instruments and laparascopic surgical instruments.
2.) Description of the Prior Art
Instruments of the above type, for example a typical endoscopic surgical instrument, has an outer flexible tubular body made from a length of coiled, closely fitting helical spring whose inside diameter is approximately 1.0 mm and whose length is approximately 200 cm. A 0.5 mm diameter wire is slidingly mounted inside of the tubular body and is connected to a pair of snippers at the distal end of the wire and an operating handle is connected to the proximal end of the wire. This is conventional construction and the intimate details of the instrument beyond the foregoing does not form a part of this invention. When these instruments are conventionally used within the body, fluids not only are deposited on the outside of the tubular instrument but also tend, because of the body pressure on these fluids and also through capillary action, to enter the space between the control wire and the inner surface of the hollow tubular body made of the coiled spring. This material within the tubular body has not been properly and completely removed by prior art cleaning methods. Normal cleaning practices to remove body fluids include soaking, scrubbing and ultrasonic cleaning in such agents as detergents and enzyme cleaners. However, the materials which have entered the tubular member are not adequately cleaned by these methods. Medical facilities tend to deal with this situation by frequent replacement of instruments or by using disposable instruments, which is a costly and wasteful means for dealing with the situation.

Apparatus for cleaning long tubular medical instruments


A regional monitoring system can establish and store patterns of signals from sensors or patterns of signals coupled to actuators. Incoming patterns can be compared to pre-stored patterns, and in the presence of a disparity therebetween, a message can be sent wirelessly to a displaced individual associated with the region indicative of the disparity. The individual can override a pre-established action associated with one of the pre-stored patterns. Monitoring systems can include security monitoring systems, fire safety monitoring systems or HVAC-type systems.

As connected home management/control systems become more common and as eco-systems of connected devices emerge, e.g. ZigBee and z-Wave, there is an opportunity to further build upon the control of certain equipment settings remotely. In fact, it is now common place to, if a homeowner thinks that he/she may have forgotten to lock a front door, check a door lock status using a remote phone via, for example, Honeywell's TOTALCONNECT brand system and TUXEDO brand home control system and remotely lock the front door using a z-Wave enabled door lock.
Products or systems with learning capabilities do exist and are publicly available. However, known systems do not provide for remote manual exception handling, which is important for locks and security.

Regional control system with manual override


A hybrid vehicle comprising a liquefied light hydrocarbon or hydrogen (LLH) fuel system is disclosed. The fuel system comprises an insulated fuel tank having a buffer space containing vaporized fuel, an orifice plate and a fuel coil conveying a first fuel vapor to a buffer tank through a first solenoid valve; a fuel line conveying a second fuel vapor through a second solenoid valve to the buffer tank and a pressure regulator, wherein an outlet to the buffer tank connects to the pressure regulator and wherein an outlet of the pressure regulator is adapted to connect to a fuel inlet to an energy conversion device selected from the group of fuel cells, Stirling engines and internal combustion engines. Methods of using the hybrid vehicle are also disclosed.

Light hydrocarbons (e.g., natural gas) are abundant in North America. In 2010, the U.S. Energy Information Administration (EIA) estimated the U.S. light hydrocarbon reserves to be about 317 trillion cubic feet. Recent developments in light hydrocarbon production have made light hydrocarbons more economical as an energy source than other petroleum oil products (e.g., gasoline, diesel fuel). Moreover, light hydrocarbons are environmentally cleaner than other petroleum fuels because light hydrocarbons produce fewer greenhouse gases (e.g., carbon dioxide, methane).
For use as a fuel, light hydrocarbons may be cooled to below their boiling point temperature to form liquefied light hydrocarbons (LLH). For example, the boiling point of non-compressed methane is about −164° C. or −263° F. at atmospheric pressure. Prior art attempts to deal with various challenges related to using a LLH fuel for vehicles powered by an internal combustion engine, such as the following: 1) insulating the LLH fuel from ambient heat; 2) vaporizing the LLH fuel before it enters a combustion chamber of the internal combustion engine; 3) providing enough LLH fuel to the internal combustion engine for sudden surges in demand for power (e.g., acceleration, high speeds, heavy loads); 4) avoiding excessive pressure-build-up inside the fuel tank from evaporation of the LLH fuel; and 5) minimizing emissions of greenhouse gases, especially vapor LLH fuel into the atmosphere when the vehicle is idle.
U.S. Pat. No. 5,373,700 describes a system for storing liquefied natural gas (LNG) and delivering vaporized LNG to an internal combustion engine. The system comprises an LNG fuel tank, a plurality of heat exchangers and gas regulator valves to maintain and control pressure inside the LNG fuel tank.
U.S. Pat. No. 5,884,488 describes a high-pressure LNG fuel system comprising an LNG fuel tank with a plurality of chambers, a cryogenic pump and an engine coolant-heated vaporizer to deliver vaporized LNG fuel to an internal combustion engine at about 3000 psig.
U.S. Pat. No. 6,698,211 describes a high-pressure LNG fuel system comprising a fuel tank, a pump and a vaporizer to deliver vaporized LNG fuel to the engine injectors at about 500 to about 3000 psig.
U.S. Pat. No. 6,058,713 describes a high-pressure LNG fuel system comprising a high-pressure fuel tank and a vaporizer using a high-pressure fuel tank to store the LNG at about 150 psi to about 1100 psi and to deliver the vaporized LNG fuel to the engine injectors at an adequate pressure.
The fuel systems described above tend to be complex, heavy, and difficult to maintain and require specialized components and materials to withstand cryogeme temperatures (e.g., cryogenic pumps, regulator valves, evaporators).
Thus, a LLH fuel system and method is needed that would be simple, light-weight, easy to maintain and utilize predominately standard components and materials.

Hybrid vehicle with a liquefied light hydrocarbon or hydrogen fuel system and methods thereto


A binarizing method for converting an image picked up by a television camera into a binary image based on a binarization level used as a threshold, includes a first step of finding a maximum value and a minimum value of a density of the image picked up, a second step of creating a histogram of the density of the image and dividing the histogram into a first region and a second region based on the maximum and minimum values of the density of the image and a predetermined first division ratio, a third step of calculating an average density of each of the first region and the second region, a fourth step of deciding a binarization level based on the average density of each of the first and second regions and a second division ratio, a fifth step of binarizing the image based on the binarization level obtained in the fourth step, a sixth step of detecting a pattern by means of a binarized image obtained in the fifth step, and a seventh step of altering the binarization level by a predetermined degree and performing the fifth and sixth steps if the pattern is not correctly detected at the sixth step and storing the binarization level in order to set the second division ratio in the fourth step based on the binarization level if the pattern is correctly detected at the sixth step. The apparatus therefor is constructed to carry out the method.

The present invention relates to a binarizing method and apparatus therefor to be carried out before the position of a position correcting mark or that of a circuit pattern placed on a substrate is recognized by an image processing apparatus in semiconductor processing equipment.
In recent years, it has become necessary to align a substrate and a mask with each other in a projecting/exposure apparatus used in semiconductor processing equipment. To this end, a method of recognizing the position of a position correcting mark has been conventionally carried out by means of a pattern such as an image without making contact with the position correcting mark.
The above-described conventional binarizing method used to recognize the position of the position correcting mark or that of the circuit pattern is described below with reference to FIG. 3.
FIG. 3 is a descriptive view of the binarizing method in which the density of an image picked up by a television camera is expressed by frequency distribution.
If an object is a position correcting mark placed on a substrate and the density of the mark is higher than that of the substrate serving as the background surface, the frequency distribution has two mountains in which the mountain having the higher density indicates the density distribution of the mark and the mountain having the lower density indicates the density distribution of the substrate.
FIG. 4 is a construction view showing a conventional position recognizing apparatus used to carry out the conventional method.
An illuminating device 3 is installed at a position diagonally above an object 2, placed on a positioning table 1, having a predetermined pattern which is to be recognized. A television camera 5 is installed on a movable television camera supporting section 4 so that the television camera 5 picks up the image of the object 2. The television camera 5 is connected with a television camera control circuit 7 for controlling the operation of the television camera 5 in response to an instruction supplied from an operation panel and a controller through a decision control circuit (CPU) 6. The apparatus further comprises a window frame control circuit 8 for setting a range to be processed according to an object and an A/D conversion circuit 9 for converting an analog value of a video signal outputted from the television camera 5 into a digital value.
A binarizing apparatus 10 surrounded by a dotted line in FIG. 4 comprises a maximum/minimum density detecting circuit 11 for detecting the maximum density fmax and the minimum density fmin in the processing range of an image to be binarized; a division level ratio storing circuit 12 for storing a division level ratio .alpha. in dividing a density histogram in the processing range into two regions; a division level calculating circuit 13 for calculating a division level INiTBiN based on the division level ratio .alpha.; a representative density calculating circuit 14 for calculating the average density Ml and Mu of each of the two regions of the density histogram divided by the division level INiTBiN; a binarization level ratio storing circuit 15 for storing a binarization level ratio .beta. in determining a binarization level BiN; a binarization level calculating circuit 16 for calculating the binarization level BiN based on the binarization level ratio .beta.; a position recognizing circuit 18 for binarizing the image based on the determined binarization level BiN and then detecting the predetermined pattern of the image by means of template matching based on the binarized image and recognizing the position thereof; and a binarization level control circuit 17 for alterably setting the binarized level BiN by a predetermined density when the predetermined pattern is not recognized.
The binarizing method to be carried out by the apparatus of the above construction is described below with reference to a flowchart of FIG. 5.
First, at step 1, the maximum/minimum density detecting circuit 11 detects the maximum density fmax and the minimum density fmin in the processing range of the image picked up by the television camera 5. At step 2, the division level calculating circuit 13 takes a frequency distribution (density histogram) of the density and divides the density histogram into two regions based on the predetermined division ratio .alpha. stored in the division level ratio storing circuit 12. A threshold to be used in dividing the density histogram into the two regions is called a division level. The division level INiTBiN is found by the following equation 1: EQU Division value level INiTBiN=fmin+.alpha..times.(fmax-fmin) (1)
Of the two regions thus obtained, the region of the smaller density is denoted by A and the region of the greater density is denoted by B. At step 3, the representative density calculating circuit 14 calculates the average densities Ml and Mu which are the representative density of each region. ##EQU1## In the above equation 2, N(f) denotes a frequency when density level is (f).
At step 4, using the average densities Ml and Mu and the binarization level ratio .beta. previously set and stored in the binarization level ratio storing circuit 15, the binarization level calculating circuit 16 determines the binarization level BiN as follows: EQU Binarization level BiN=Ml+.beta.(Mu-Ml) (3)
At step 5, the position recognizing circuit 18 binarizes the image by using the binarization level BiN thus determined, thereby recognizing the position of the pattern.
If the position of the pattern is correctly recognized, the binarization level BiN is appropriate. If the position of the pattern is not correctly recognized, the binarization level BiN is inappropriate. At that time, at step 6, the binarization level control circuit 17 alters the binarization level BiN by the predetermined density and the position recognizing circuit 18 binarizes the image based on the altered binarization level BiN and thus recognizes the position of the pattern until the position of the pattern is correctly recognized. If the position of the pattern is not correctly recognized notwithstanding the repeated alteration of the binarization level BiN, it is decided that the binarization level BiN is not inappropriate, but that the state of the object is inappropriate.
However, according to the above-described conventional method, in an apparatus in which chemical reactions, for example, semiconductor processes take place, the states of circuit boards are chemically varied lot by lot and as a result, and the characteristic of the density histogram of an image such as a position recognizing pattern or mark nonlinearly changes. Therefore, it is necessary to alter the binarization level many times and consequently much time is required for image processing.

Binarizing method and apparatus therefor

Matsushita Electric Industrial Co., Ltd.


The present invention is a sintering material including a granule, the sintering material having an apparent tap density of 1.0 to 2.5 g/cm3, a 50% cumulative volume particle diameter (D50N) of 10 to 100 μm as measured before ultrasonication by laser diffraction/scattering particle size distribution analysis, a 50% cumulative volume particle diameter (D50D) of 0.1 to 1.5 μm as measured after ultrasonication at 300 W for 15 minutes by laser diffraction/scattering particle size distribution analysis, and an X-ray diffraction pattern in which the maximum peak observed in the 2θ angle range of from 20° to 40° is assigned to a rare earth oxyfluoride of the form LnOF when analyzed by X-ray diffractometry using Cu—Kα or Cu—Kα1 rays.

A halogen gas is used in an etching step in the fabrication of semiconductor devices. In order to protect an etching apparatus from corrosion by halogen gas, the inner side of the etching apparatus is usually coated with a highly anti-corrosive substance by, for example, thermal spraying. It has also been practiced to construct the internal parts of the apparatus from a sintered body of a highly anti-corrosive substance. Materials containing a rare earth element are often used as such a substance.
Materials containing a rare earth element for use as a thermal spray material are usually granulated into flowable granules. Raw materials for use as a sintering material are also granulated.
Among known thermal spray materials containing a rare earth element is a particulate rare earth oxyfluoride having an aspect ratio of 2 or smaller, an average particle size of 10 to 100 μm, and a bulk density of 0.8 to 2 g/cm3 and containing not more than 0.5% by mass of carbon and 3 to 15% by mass of oxygen. It is known that this thermal spray material can be prepared by granulation (see Patent Literature 1 below).
There is a method for producing rare earth oxide solid spherical particles comprising dispersing a rare earth oxide powder with an average particle size of 1 μm or smaller in water to prepare a slurry and adding an organic acid salt to thereto, followed by spray drying. It is known that the resulting rare earth solid spherical particles are useful to make a sintered body (see Patent Literature 2).
A known method for producing a rare earth fluoride sintered body having high resistance to corrosion by a halogen-based plasma comprises molding a Group 3A metal fluoride powder containing a total of not more than 100 ppm of metal elements other than the group 3A metal and having an average particle size of 30 μm or smaller to form a green body of prescribed shape and firing the green body to a relative density of 95% or higher (see Paras. [0025]-[0028] of Patent Literature 3).
An oxyhalide-based member is disclosed, the part of which that is to be exposed to a halogen (e.g., fluorine or chlorine) corrosive gas or a halogen-based plasma is a sintered body represented by general formula: LnZ3−2xOx (wherein Ln is one or more of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; Z is one or more of F, Cl, Br, and I; and 0<X<1) (see Para. [0005] of Patent Literature 4).

Sintering material, and powder for manufacturing sintering material


Oil or other combustible material polluting the sea is burned by apparatus having a partly submergible burner equipped with a transducer for generating high frequency acoustic vibrations. The transducer is surmounted by a velocity transformer designed to concentrate the acoustic vibration at a region of maximum intensity adjacent an upper end of the transformer. A float arrangement on the burner allows buoyancy to be adjusted so that the upper end of the velocity transformer is disposed a suitable distance above the surface of the water. An ignition system on the burner projects upwardly above the velocity transformer to ignite a cloud of the oil which is vaporized over the apparatus by energization of the transducer.

The problem of cleaning up an oil spill in a harbour or near a coastline line is well known and a great variety of proposals have been made in vain attempts to offer solutions to the problem. One suggestion is to burn off the oil by dropping magnesium particles and then setting fire to the oil-magnesium mixture in the hope that sufficient heat will be generated to support combustion long enough to consume a reasonably large amount of the spilled oil. However, often there are such high thermal losses to the water and air that combustion cannot be maintained and the first soon dies out leaving the water polluted to a greater degree than before by the additional products of combustion and unburned magnesium particles.

Method and apparatus for atomizing and burning liquid hydrocarbons floating on water


In a system wherein a plurality of communication units are connected to a bus to exchange mutual communication and a collecting communication unit collects state information indicating respective states from report communication units to manage their state information, the collecting communication unit includes an address setting portion for setting information indicating that own unit is a unit for collecting state information as identification information, and each of the report communication units includes a report command setting portion for setting identification information as a destination address and also a report command including a destination address and the state information and a transmitting portion for transmitting the report command to the collecting communication unit based on the destination address in the set report command.

1. Field of the Invention
The present invention relates to a state information managing method which is able to manage easily state information of respective communication units and also reduce a communication traffic volume required for management of state information in a communication system wherein a plurality of communication units for exchanging data communication mutually are connected to a bus, and a system embodying the same.
2. Description of the Prior Art
In a communication system in which a plurality of communication units are connected to a bus, respective communication units can exchange data communication mutually. At this time, since internal states of respective communication units are changed with the lapse of time, state information indicating the internal states have been managed by the communication units respectively.
As the state information management method, there has been such a method that, when the data management portion issues a state request to respective communication units, such respective communication units transmits a state response to the data management portion in response to the state request from the data management portion. However, according to this method, since the state request and the state response must be issued from respective communication units, an extensive communication traffic volume has been needed.
Therefore, there has been known the first method to reduce the communication traffic volume of the state request. In the first method, once the state request has been issued after a state information collecting destination has been identified clearly, the communication units which receive such state request have transmitted automatically state reports to the state information collecting destination subsequently every time when their states are changed. According to the first method, the communication traffic volume of the state request can be reduced.
However, according to the above first method, since information as for the state information collecting destination must be transmitted to respective communication units, communication for informing respective communication units of such information as for the state information collecting destination have not been able to be omitted.
In addition, as the second method to reduce the communication traffic volume of the state request, there has been a method set forth in Patent Application Publication (KOKAI) Hei 6-68000, for example. According to this method set forth in Patent Application Publication (KOKAI) Hei 6-68000, temporary addresses which are different from individual addresses are temporarily set, then such temporary addresses are distributed to any objective terminal devices on a transmission line, and then only the objective terminal devices can be controlled every temporary address by virtue of communication frames.
However, in the second method, the temporary addresses has had to be transmitted to respective terminal devices which need the state information. Therefore, according to the second method, it has been difficult to reduce the communication traffic volume smaller than that in the first method.

State information managing method and system embodying the same


An ion beam scanner includes a first scanner stage having a first opening to transmit an ion beam, the first scanner stage to generate, responsive to a first oscillating deflection signal, a first oscillating deflecting field within the first opening; a second scanner stage disposed downstream of the first scanner stage and having a second opening to transmit the ion beam, the second scanner stage to generate, responsive to a second oscillating deflection signal, a second oscillating deflecting field within the second opening that is opposite in direction to the first oscillating deflecting field, and a scan controller to synchronize the first oscillating deflection signal and second oscillating deflection signal to generate a plurality of ion trajectories when the scanned ion beam exits the second stage that define a common focal point.

In the present day, ion implanters are often constructed to optimize implantation according to a specific set of applications. In current applications, for example, some beamline ion implanters are configured to generate high current ribbon beams in which the beam cross section that intercepts a substrate has a beam width that is much greater than the beam height. In some configurations the beam width is slightly larger than the size of a substrate at the substrate plane e.g., 200, 300, or 400 mm, while the beam height is on the order of 10 mm, 20 mm, or 30 mm, for example. By scanning the substrate with respect to the ribbon beam in the direction of the beam height, the entire substrate may be implanted by the ion beam.
For other ion implantation applications, it may be preferable to use a spot beam ion beam in which the beam height and beam width are more equal. One advantage afforded by spot beam ion implantation is the better control of dose uniformity afforded by spot beams. In a spot beam ion implantation application, the spot beam may be scanned along a first direction to cover the dimension of a substrate in that direction that is being implanted. At the same time, the substrate may be scanned in a direction perpendicular to that of the scan direction of the spot beam. The local ion dose concentration can be modified by adjusting the speed of the ion beam along the direction of spot beam scanning. This can be accomplished under computer control in a manner that allows the spot beam scanning to be carefully controlled to optimize ion dose uniformity.
In many beamline ion implanters, after exiting a mass resolving slit, the ion beam may propagate as a wide beam of diverging ions to a collimator, which form a collimated ion beam that is directed to the substrate being processed. In order to provide the correct collimation of the ion beam, the collimator is often set to collimate ions that originate from an object that is placed at the plane of the mass resolving slit (MRS). This feature makes it more difficult to operate the same beamline in both spot beam mode and ribbon mode. In ribbon beam mode, the ion trajectories generated by an analyzer magnet may focus at the MRS to fan out into the collimator situated downstream. However in a conventional ion implanter in a spot beam mode the ion beam may pass through the mass resolving slit as a small beam having more parallel ion trajectories. After exiting the mass resolving slit, the spot beam is then deflected back and forth in a scanner by a deflecting field oriented generally perpendicularly to the direction of propagation of the spot beam. This scanning of the spot beam forms a diverging fan of ion trajectories over time that enters the collimator. The object location in this spot beam configuration is within the scanner that is located downstream of the mass resolving slit. The object location of a spot beam generated from a scanner may therefore vary too much from the object location of a ribbon beam for a collimator to properly collimate both types of beams without extensive reconfiguration. Accordingly, it is common practice for a ribbon beam ion implanter to be employed for certain ion implantation steps or for certain substrates, such as high dose implantation, while a separate spot beam ion implanter is employed for other ion implantation steps that require better dose control. It is with respect to these and other considerations that the present improvements have been needed.

Varian Semiconductor Equipment Associates, Inc.


The horizontal spool tree assembly 10 controls fluid flow through a production tubing string 18 within a well. The horizontal spool tree assembly is adapted for use with a workover string for fluid communication with the tree assembly. The spool body 12 has a central bore 14 for receiving a tubing hanger 22 therein, with a production passageway extending laterally through the spool body to a production line 36. The spool body also includes an annulus passageway extending laterally through the spool body for fluid communication between the tubing annulus 16 and the annulus line 52. The spool tree assembly has improved porting for the production line and the annulus line, and also for both workover and crossover operations.

Wells are frequently completed with a "horizontal tree", i.e., a production system which contains one or more hangers in a spool body with a lateral production passageway in fluid communication with a production tubing string, and a tree cap above the tree hanger. A port through the spool body passes production fluids from the production tubing laterally through the spool body and then to the surface via a production flow line. Retrievable plugs are commonly installed in the bores of both the tree cap and the tubing hanger. Exemplary prior art is disclosed in U.S. Pat. Nos. 5,544,707, 5,706,893, 6,050,339, 6,039,119, 6,227,300, and 6,470,968. Relevant publications are U.S. 2001/0011593, 2002/000322 2002/0000315, 2003/0089501 and WO01/73259.
Various types of equipment and techniques have been proposed for the workover of horizontal spool tree wells. Workover operations are conventionally performed utilizing a floating drilling rig with a subsea BOP connected to the top of the horizontal spool tree, and a drilling riser connected to the top of the BOP. When a big bore riser and a BOP stack are placed on top of the tree, various types of workover operations may be performed, including pulling and reinstalling the tubing. One or more workover strings provide fluid communication with the horizontal spool tree assembly, with the workover fluid passing through the tree cap and to the tubing annulus. A running tool may be used to seal off the top of the tubing hanger and to pull a plug if one is provided in the top of the tubing hanger to close off the tubing string.
Workover porting of the tubing annulus may be accomplished utilizing valves in a line extending through the tubing hanger for fluid communication with the tubing annulus. Valves external of the spool body or within the spool body have alternatively been used to route the tubing annulus line around the tubing hanger to various locations within the spool body.
Horizontal spool trees also desirably provide a crossover line between the production line and the annulus line. If for some reason the production line needs to be shut down, flow may be diverted through the crossover line to the annulus line and then to the production platform. The crossover flow line is thus located closely adjacent the horizontal spool tree assembly, and conventionally is located within twelve feet of the production bore.
Horizontal spool trees also include an annulus port and an annulus line which conventionally extends from the spool tree assembly to the production platform. The annulus line enables annulus pressure which is excessive to be bled off, thereby maintaining a desired pressure differential between the interior and the exterior of the tubing string.
The disadvantages of the prior art are overcome by the present invention, and a horizontal spool tree with improved porting is hereafter disclosed.

Horizontal spool tree with improved porting


A method for minimizing the rate of collision of a mobile robotic device. A mobile robotic device selects controls comprised of sets of actions to navigate through a workspace. Controls resulting in non-collisions cause the system to earn a positive reward. Controls resulting in collisions cause the system to earn a negative reward. Cumulative rewards over the course of a work session are compared to the cumulative rewards of other work sessions. A policy is defined based on outcomes of prior work sessions to minimize the expected number of collisions.

Robotic devices are used in a variety of applications for carrying out tasks autonomously. One problem robotic devices face is avoiding collisions while driving through an environment. Different types of sensors are commonly used to identify obstacles and avoid collisions. A robotic surface coverage device may drive through an area faster when fewer collisions are incurred, and thus a job of a robotic surface coverage device may be completed more efficiently. A need exists for a method to reduce the rate of collisions in mobile robotic devices.

Method to minimize collisions of mobile robotic devices


In an image processing apparatus, an image reading unit reads a document put on a platen glass to generate image data, and a detector in the image reading unit detects a tilt angle of the document put on the platen glass. A rotation angle is set based on the image data of a document and the image data is modified according to the rotation angle. The modification is controlled so as not to deteriorate the image quality. For example, the image data is rotated by an angle at which the document is tilted when the document is read, if the detected tilt angle of a document is larger than a predetermined value. The modification of the image data may be controlled according to a characteristic of the image data. For example, the image data is not rotated when the document is decided to include a half-tone image by detecting the attribute of the image data. Preferably, a magnifying power for reading the document is calculated according to the detected tilt angle, and the image data are read again at the magnifying power. Then, the optically magnified image data of the document is rotated by the tilt angle.

1. Field of the Invention
The present invention relates to an apparatus for processing image data and more particularly to an apparatus which processes image data read by an image reader.
2. Description of Prior Art
A document is put on a platen glass when it is read by an image reader. When the document is put on the platen glass at an erroneous position, it is desirable to correct the tilt of the document. Then, a function is proposed to rotate 2-dimensional image data obtained by a document reader by the tilt angle of the document (for example, Japanese Patent Publication 63-9266/1988). In the tilt angle rotation, inclination of a document put on a platen glass is detected, and the image data are rotated to the normal position. Then, an image is formed on a paper based on the corrected image data. Thus, when a user put a document at a tilt unintentionally, its image can be output by automatically correcting the tilt of the image.
However, in the prior art tilt correction by rotating the image data by the tilt angle, the image is processed automatically in the same process regardless of a simple bi-level image such as a character image or a half-tone image such as a photograph. Further, the processing is similar irrespective of the magnitude of the rotation angle. For a character image, the image after the tilt angle rotation keeps about the same image quality (for a resolution of about 400 dots per inch). On the other hand, for a half-tone image, the image quality is deteriorated disadvantageously after the rotation. For example, the image becomes rough at half-tone image areas. Especially, the deterioration becomes worse if the rotation angle becomes larger, for example more than about 10.degree.. It is to be noted that it is difficult to use a single criterion for the tilt angle rotation, because half-tone images include various kinds and user's purposes for image forming are also different.
If multi-level image data (data having gradation) are subjected to the tilt angle rotation, image deterioration on the tilt angle rotation is suppressed to some degree. However, this needs a complicated structure, and the processing speed becomes slow. Further, the cost increases to a large extent.
For a half-tone image, high image quality is required, and smoothing or the like is needed in the data modification.
However, for a document including half-tone and character images mixed with each other, smoothing for a character image (simple bi-level image) may worsen image quality reversely. When an image is formed, it is convenient for a user to automatically correct the tilt of a document, but deterioration of image quality is a problem.
Further, for a document including half-tone and character images mixed with each other, deterioration of image quality is less for a character image (simple bi-level image) than for a half-tone image. Thus, the image quality subjected to the rotation becomes different between the character image areas and the half-tone image areas. When such an image formed on a sheet of paper is viewed, the entire image seems not well.
In a prior art tilt correction technique, it is known to combine image data shift in two scan directions with 90.degree. rotation. In order to prevent size change of the image, electric magnification is performed after the shifting in each scan direction. However, when electric magnification is performed for each shifting, line insertion or the like happens by the electric magnification, and this deteriorates the image. Further, processing time for the rotation becomes longer.

Image processing apparatus including image rotator for correcting tilt of the image data


A shaker screen comprises a frame that has a plurality of opposing sides. The shaker screen also comprises a screen assembly attached to the frame. In addition, each side of the shaker screen comprises a tubular member having an inner edge, an outer edge, and defining a central axis. Further, a horizontal plane intersects the central axis, the outer edge, and the inner edge of each side.

1. Field of the Disclosure
The present disclosure relates generally to the shale shaker screens used to filter solids out of drilling mud.
2. Description of Related Art
When drilling a well (e.g., for oil or gas), a drill bit is attached to the end of a drill string and drills a hole through the subsurface to access the oil or gas reservoir. Drilling fluid is used during drilling operations. Drilling fluid comprises, for example, a finely ground clay base material to which various chemicals and water are added to form a viscous fluid designed to meet specific physical properties appropriate for the subsurface conditions anticipated. This drilling fluid is pumped down the hollow drill pipe, through the drill bit and returned to the surface in the annular space between the drill pipe and the well bore.
The drilling fluid serves three main purposes. First, it aids in cooling the drill bit and thereby increasing its useful life. Second, the mud flushes the cuttings or "solids" from the well bore and returns them to the surface for processing by a solid control system. Third, the mud leaves a thin layer of the finely ground clay base material along the well bore walls which helps prevent caving in of the well bore wall.
Although often referred to simply as "mud," the drilling fluid is a complex composition which must be carefully engineered and tailored to each individual well and drilling operation. The drilling fluid is costly and, thus, is cleaned and reused in a closed loop system in which a solids control system and a shaker play important roles.
A shaker, often referred to as a "shale shaker," is part of a solids control system used in oil and gas drilling operations to separate the solid material ("solids"), removed from the well bore by the drilling operation, from the drilling mud. For the drilling fluid to be used and reused, it must be processed after returning from the well bore to remove the aforementioned solids and maintain its proper density, often expressed as pounds per gallon or "mud weight", i.e., 10 lb./gal. mud or "10 lb. mud". The first step in processing the returned drilling fluid is to pass it through a shaker. The returned drilling fluid from the flow line flows into a possum belly, a container mounted at one end of the shaker, and then flows over one or more screens. A shaker includes a support frame on which the shaker screen is mounted. One or more motors in the shaker causes the screen assemblies to vibrate or oscillate, depending on the type of motors utilized. The vibrating action of the screens over which the mud passes removes larger particle size solids (e.g., in the 200 to 700 micron size range) while allowing the drilling fluid and smaller particle size solids to pass through the screen. Solids, which are discarded from the top of the shaker screen, discharge into a pit or onto a conveyor for further treatment or disposal and the underflow drilling fluid flows into the tank below.
A common means to secure the screen in the shaker is through the use of a wedge block. A wedge block is typically inserted between the screen and a bracket located along the inside walls of the shaker. The wedge block is pushed further back under or into the bracket, in turn pushing the wedge downward onto the screen and onto the shaker. Two wedges are typically used per screen, but other combinations of wedges may be utilized.
A common means to seal the screen in the shaker is through the use of gaskets secured to the shaker at the screen interface. The gasket is typically secured to the shaker with various fasteners that wear out due to contact with the drilling fluid and solids. Thus, maintenance is required to replace worn gaskets and/or fasteners. Replacing the gaskets is time- and labor-intensive—the shaker must be taken offline, the wedge blocks removed, the screens removed, the fasteners ground off, the old gasket material removed, and the new gaskets installed with new fasteners, and then the screens and wedge blocks reinstalled.
Accordingly, there remains a need in the art for a shaker screen and sealing gasket capable of easy and efficient replacement, while retaining the necessary securing and sealing properties within a shaker device.

Shale shaker screen and fastening system