In order to improve security for holographic labels which are positioned on a substrate base, a bar code symbol is holographically recorded on the base such as a credit card, a label, or a container for a product. A reading apparatus (e.g., a bar code reader) directs light at the holographic bar code symbol and detects the reflected optical information with a detector such as a CCD array. The reading apparatus can be a stand-alone device or, in the case of a credit card, can be incorporated into a conventional swiper for reading magnetic information on a strip on the card. A non-holographic bar code symbol can also be provided on or near a holographic display element, e.g., a rainbow hologram. The bar code can be positioned adjacent the display, or placed in a window within the display, or etched or embossed on the display. A system is also provided for authenticating a holographic display on an information card such as a credit card. A display is illuminated and a reflected beam directed at a holographic record which was previously produced from a signal, known to be authentic, and a reference. The reflected beam is used to reconstruct a reference beam. A sensor receives the reconstructed reference and it is then determined if the display is authentic.

This invention relates to holographic display elements used for authentication.
In order to discourage fraudulent manufacture of information cards, and particularly credit cards, card manufacturers have been incorporating a holographic pattern or display on the face of the cards. A hologram is a recording of an interference pattern between two beams of light, usually referred to as the signal beam and the reference beam. The signal beam usually includes the image to be recorded, and the reference beam is a beam of light, usually of constant distribution, i.e., plane or spherical wavefront. Typically, another reference beam which is similar, but not necessarily identical, to the one used to record the hologram, is used to reconstruct the signal beam, which then produces an identifiable image. For most holograms, one cannot identify the recorded image without reconstruction.
The holograms typically used on credit cards are what are known as rainbow holograms. They are produced by placing the image to be recorded near the surface of the holographic substrate during recording. These holograms are visible in ordinary, white light and are familiar to many holders of credit cards. The rainbow hologram can be mass produced on sheets of metallized embossing substrate, and stamped onto a credit card. Such holograms are a deterrent to counterfeiting because their production requires an expensive manufacturing investment. Counterfeiting is still a potential problem, however, because with a large enough investment in equipment counterfeit holograms can be produced. Moreover, detecting a counterfeit hologram may be difficult, because of the inherent difficulty of accurately comparing two holograms with just the naked eye.

Authentication system for an item having a holographic display using a holographic record


Methods, systems, and computer-readable media provide for providing an indication of hightime. According to embodiments, a method for providing an indication of hightime is provided. According to the method, whether at least one of a plurality of technicians exceeds an allotted time with which to complete a job is determined. In response to determining that at least one of the plurality of technicians exceeds the allotted time, an indication that at least one of the plurality of technicians exceeds the allotted time is provided.

Telecommunications networks may provide a number of services, such as plain old telephone service ("POTS"), digital subscriber line ("DSL"), and cable. A telecommunications network may be divided into a plurality of geographic areas known as turfs. Maintenance of the telecommunications network generally involves a proper reallocation of technicians across the turfs such that work orders can be timely filled. For example, when one turf experiences a high volume of work orders, it may be desirable to reallocate available technicians from another, preferably nearby, turf with a low volume of work orders to help with the high volume. The reallocation of technicians may be based on a number of factors, such as the location, skills, schedule, and availability of the technicians, as well as the priority of the work orders and the amount of time to complete the work orders.
Each technician generally works a given amount of time during a work shift. A common work shift is approximately eight hours. Each technician may be assigned a schedule of a plurality of jobs to complete during the work shift. To properly allocate jobs to each technician and to facilitate a proper management of each technician's workload, each job on the schedule may be given an estimated start time and an estimated duration for completion. When the time spent by a technician on a given job exceeds the estimated duration for the job, a number of problems may arise. For example, the technician may not make the estimated start time for a next job on the schedule or, in some cases, may even miss the appointment for the next job entirely.
A load balance supervisor ("LBS") may be assigned to coordinate the reallocation of technicians within a plurality of turfs. The LBS conventionally relies on retrieving the schedules of the technicians and manually manipulating data to determine whether a technician has exceeded the duration for completion of a given job. If the LBS manages a substantial number of technicians or is under a heavy load, the LBS may not determine that a technician has exceeded the duration for completion of a given job until it becomes too late to take any corrective action.

Methods, systems, and computer-readable media for providing an indication of hightime


The new variety ‘TH-929’ is provided. The new and distinct variety ripens around the second week of May in southern Georgia. The fruit of the new variety ‘TH-929’ are very large, firm, and have good flavor. The new variety ‘TH-929’ is vigorous with an estimated chilling requirement of about 500 to 550 hours at or below approximately 7° C. The asexually reproduced variety is reliably propagated vegetatively.

The present invention relates to the discovery of a new and distinct cultivar of southern highbush blueberry plant botanically known as a Vaccinium corymbosum L. and herein referred to as 'TH-929', as herein described and illustrated.
The new blueberry plant variety 'TH-929' was selected in Griffin, Ga. in 2005. The new variety 'TH-929' ripens around the second week of May in southern Georgia. The fruit of the new variety 'TH-929' are large and have good flavor. The new variety 'TH-929' is vigorous with an estimated chilling requirement of about 500-550 hours at or below approximately 7° C.
Pedigree and history: 'TH-929' was selected in 2005 at the Georgia Experiment Station in Griffin, Ga., originating from a cross of 'TH-622' X 'Millennia' made by Dr. D. Scott NeSmith in 2002. The female parent ('TH-622') is a non-patented breeding line, and the male parent, 'Millennia', is the subject of U.S. Plant Pat. No. 12,816. The new variety was first asexually propagated in Griffin, Ga. by softwood cuttings. Asexual propagation by softwood cuttings has also been performed in Alapaha, Ga. The selection has been tested in plantings at Alapaha and Griffin, Ga. established in Fall 2007. In 2010, the variety was entered into preliminary trials at sites in California. In 2012 'TH-929'was entered into growing trials in Peru and Mexico. The new blueberry plant variety 'TH-929' has been shown to maintain its distinguishing characteristics through successive asexual propagation by softwood cuttings in Griffin and Alapaha, Ga. Plants from softwood cuttings have been directly planted in the ground.

Southern highbush blueberry plant named ‘TH-929’

University of Georgia Research Foundation, Inc.


A video node for use in rendering one or more video frames of a video stream. The video node is represented by a compositing tree (2100). The compositing tree (2100) comprises at least one image primitive node (2140) representing one or more video frames (2300) of the video stream. At least one of the video frames (2300) represented by the image primitive node (2140) is composited with at least one further graphical primitive represented by at least one further primitive node (2130) of the compositing tree (2100). The video frame (2300) is composited with the further graphical primitive according to a compositing operation represented by an operation node of the compositing tree (2100) in order to generate a composite image (2303) represented by at least one composite node (2150) of the compositing tree (2100).

Many existing graphics rendering systems provide images, text and line work as "primitives". The term primitive refers to a base graphical element used in the creation of a complex graphical image. In order to display video images on such graphics rendering systems, software applications executing on the systems need to constantly update the contents of image primitives. These software applications also have to process audio data associated with the image primitives. The need to update image primitives constantly makes it difficult for software applications to process multiple video streams, or to composite multiple video images and still images.
In order to improve the processing of multiple video streams, some existing graphics rendering systems provide video images as a series of image primitives. However, these rendering systems are typically limited in their ability to composite video with other video or still graphical primitives or to create special effects. Such rendering systems typically also require special hardware.
Thus a need clearly exists for an improved method and apparatus for rendering an image and, in particular, for rendering video images.


Apparatus is disclosed for non-invasively monitoring a subject's blood pressure, in which a flexible diaphragm that encloses a fluid-filled chamber is compressed against tissue overlying an artery, with sufficient force to compress the artery. A first, relatively slow servo control system optimizes the amount of artery compression, which occurs at a mean transmural pressure of about zero, by modulating the volume of fluid within the chamber and noting the resulting effect on the pressure within the chamber. Since different pressure effects are realized according to the amount of artery compression, an appropriate control signal can be produced that provides the optimum mean diaphragm pressure. In addition, a second, relatively fast servo control system supplies the fluid to and from the chamber, so as to compensate for pressure variations within artery. This minimizes variations in the artery's effective diameter, whereby the pressure within the fluid-filled chamber closely follows the actual arterial pulse waveform.

This invention relates generally to apparatus and methods for monitoring a subject's arterial blood pressure and, more particularly, to such apparatus and methods that monitor arterial blood pressure non-invasively by applying a pressure sensor against tissue overlying an arterial blood vessel, to partially applanate or compress the vessel.
Two well known techniques have been used to non-invasively monitor a subject's arterial blood pressure waveform, namely, auscultation and oscillometry. Both techniques use a standard inflatable arm cuff that occludes the subject's brachial artery. The auscultatory technique determines the subject's systolic and diastolic pressures by monitoring certain Korotkoff sounds that occur as the cuff is slowly deflated. The oscillometric technique, on the other hand, determines these pressures, as well as the subject's mean pressure, by measuring actual pressure changes that occur in the cuff as the cuff is deflated. Both techniques a determine pressure values only intermittently, because of the need to alternately inflate and deflate the cuff, and they cannot replicate the subject's actual blood pressure waveform. Thus, true continuous, beat-to-beat blood pressure monitoring cannot be achieved using these techniques.
Occlusive cuff instruments of the kind described briefly above generally have been effective in sensing long-term trends in a subject's blood pressure. However, such instruments generally have been ineffective in sensing short-term blood pressure variations, which are of critical importance in many medical applications, including surgery.
One technique that has been used to provide information about short-term blood pressure variations is called arterial tonometry. One device for implementing this technique includes a rigid array of miniature pressure transducers that is applied against the tissue overlying a peripheral artery, e.g., the radial artery. The transducers each directly sense the mechanical forces in the underlying subject tissue, and each is sized to cover only a fraction of the underlying artery. The array is urged against the tissue, to applanate the underlying artery and thereby cause beat-to-beat pressure variations within the artery to be coupled through the tissue to the transducers.
The rigid arterial tonometer described briefly above is subject to several drawbacks. First, its discrete transducers are relatively expensive and, because they are exposed, they are easily damaged. In addition, the array of discrete transducers generally is not anatomically compatible with the continuous contours of the subject's tissue overlying the artery being sensed. This has led to inaccuracies in the resulting transducer signals. In addition, in some cases, this incompatibility can cause tissue injury and nerve damage and can restrict blood flow to distal tissue. Another drawback is that such rigid arterial tonometers have failed to correct for signal artifacts that arise when the subject's arm is moved. This is a particular problem when the subject is exercising or otherwise ambulating.
Yet another drawback to the arterial tonometer described briefly above is its inability to continuously monitor and adjust the level of arterial wall compression to an optimum level of zero transmural pressure. Generally, optimization of arterial wall compression has been achieved only by periodic recalibration. This has required an interruption of the patient monitoring function, which sometimes can occur during critical periods. This drawback is perhaps the most severe factor limiting acceptance of tonometers in the clinical environment.
Another device functioning similarly to the arterial tonometer includes a housing having a closed, liquid-filled chamber with one wall of the chamber defined by a flexible diaphragm. The device is applied against a subject's skin, with the flexible diaphragm pressed against the tissue overlying a peripheral artery, e.g., the radial artery, and several electrodes located in separate compartments of the chamber sense volume changes in the compartments that result from the beat-to-beat pressure variations in the underlying artery. Although the device seeks to replicate the arterial pressure waveform, it is considered to have a relatively low gain, making it unduly susceptible to noise. Further, the device must be calibrated periodically, during which time its continuous monitoring of the subject's blood pressure waveform necessarily is interrupted.
It should, therefore, be appreciated that there is a continuing need for an apparatus, and related method, for non-invasively and continuously monitoring a subject's blood pressure, with reduced susceptibility to noise and without the need to intermittently interrupt the device's normal operation for calibration. The present invention fulfills this need.

Apparatus and method for non-invasively monitoring a subject's arterial blood pressure


An automatic flap that uses on each wing two adjacent fins, one of which is smaller and is located on the middle or front of the wing, the other, which is larger, on the bottom rear of the wing, with a shaft in the common eccentric zone linking the two fins, said shaft being parallel to the axis of the wing, having the fins different resistance to the ram air, creating a rotation torque as a function of the aircraft's speed, when retracted, they are shaped so that the front or top fin adapts to the upper surface of the wing and the rear or bottom fin adapts to the lower surface so that, together with the wing, they form an aerodynamic profile, there are attachment arms between the two fins, and bands or springs to assist or complement the action of the smaller fin whose resistance is such that, at low speed, the flap remains extended.

1. Field of the Invention
This invention refers to a high-lift aircraft flap necessary for low-speed flight.
2. Description of the State of the Technique
At present, flaps are manually operated and controlled by complex, duplicated and heavy devices or when they are automatic they need a big force or big springs for the actuation.


An alumina-titanium oxide-zirconia fused grain presenting, for a total of 100%, the following chemical composition:                Al2O3: more than 10% and less than 50%;        TiO2: more than 10% and less than 40%;        ZrO2: more than 50%; and        impurities: less than 2%;the percentages being percentages by weight on the basis of the oxides. The invention is applicable to slide gates for continuous casting of steel.

Slide gates are parts used in continuous casting of steel for opening and closing distributors or outlet orifices from casting ladles in fluid communication via a sliding nozzle with ingot molds. Slide gates must therefore present good mechanical strength, in particular against thermal shocks and spalling, and good chemical resistance, in particular against corrosion.
Conventionally, slide gates are obtained by sintering a mixture of alumina-zirconia fused grains and zirconia-mullite fused grains. The alumina-zirconia/zirconia-mullite composite is particularly good at withstanding thermal shocks because of its reinforcement by microcracking. During heating, the allotropic transformation of zirconia is accompanied by a large change in volume. This dimensional variation leads to the formation of microcracks. These microcracks also appear at the interfaces between zirconia-mullite particles and the alumina-zirconia matrix because of the large difference in thermal expansion between alumina-zirconia (α1000°C.=9.6×10−6/° C.) and zirconia-mullite (α1000°C.=6.9×10−6/° C.). These two phenomena lead to the part being microcracked, thereby increasing its capacity for absorbing energy in the event of thermal shocks.
Nevertheless, zirconia-mullite presents the disadvantage of presenting low resistance to corrosion, thus constituting the weak point of the composite.

Alumina-titanium oxide-zirconia fused grain

Saint-Gobain Centre de Recherches et d'Etudes Europeen


A sensor module includes a substrate having a cavity in a surface thereof; a first sensor inside the cavity; a second sensor inside the cavity; and a lid body sealing the cavity and including an internal surface. The second sensor includes a first electrode located on an internal surface of the lid body and a second electrode located in the cavity.

1. Field of the Invention
The present invention relates to a sensor module in which a plurality of sensors are integrated, a wheel with a sensor and a tire/wheel assembly.
2. Description of the Related Art
In general, in order to simultaneously measure a plurality of physical quantities of a physical object, sensors corresponding to kinds of the physical quantities to be measured are necessary.
For example, there is a sensor device in which an acceleration sensor and a pressure sensor are arranged within one package. The acceleration sensor, the pressure sensor and an integrated circuit are arranged in parallel on one board surface of one large board.
In the case where it is necessary to attach a plurality of sensors to the physical object, if the number of the sensors is increased, the number of attaching positions is increased, and the mounting area of the sensors in the physical object is increased. As a result, not only the device structure becomes complicated, but also a characteristic of the physical object itself may be changed.

Sensor module, wheel with sensor and tire/wheel assembly


The present invention provides a hydroelectric device including generally a base portion with a top surface, a bottom surface, and opposing sidewalls defining an interior space of the base portion. The interior space of the base portion is such that it is wider near the ends of the base portion and narrower in the interior of the base portion, essentially forming a venturi. The base portion also includes a central slot along a longitudinal axis thereof. The present invention further includes a wheel support portion fixedly attached to the base portion, a wheel portion rotatably attached to the wheel support portion and having a plurality of blades extending from a center thereof, and an electrical generator operably engaged with the wheel portion.

Mankind has made use of the power of water for thousands of years. The ancient Greeks used waterwheels to grind wheat into flour more than two-thousand years ago, and waterwheel technology spread across Europe during the height of the Roman empire. Over the subsequent millennia, hydropower technology spread to a variety of applications, including the production of electricity.
Hydroelectric power is generally known in the art, and hydropower is a common means of producing electricity around the world. In some South American countries, hydroelectric power accounts for more than 50% of the national supply of electricity. Most hydroelectric power is generated from the potential energy stored in water when that water is dammed and held, for example, in a reservoir. That potential energy is converted to kinetic energy when water is released from the reservoir through the dam, and the kinetic energy of the released water operates a turbine, which results in the production of electricity therefrom. A chief advantage of hydroelectric power is that, because hydroelectric facilities do not require an external fuel source, they are immune to variations in prices for fossil fuels such as oil, natural gas, or coal.
Despite the advantages of hydroelectric power, the hydroelectric facilities in existence today suffer from a number of drawbacks. With respect to the reservoir-and-dam method of producing electricity from hydropower, the amount of energy extracted from the water depends directly on the difference in height between the source of the water and the water outflow (this difference is referred to in the art as the head). Thus, such systems are not well-suited to use in areas having a substantially flat geography. Large hydroelectric facilities may also have undesirable environmental impacts. For example, dams along the pacific coast of North America have been shown to reduce the indigenous salmon population by preventing access to spawning grounds upstream. Engineers have attempted to address this issue by installing 'fish ladders' at many dams, but the results have shown only a limited success.
In addition to impacting fish populations, hydroelectric dams have an effect on downstream riverbeds. Because the water exiting the turbine generally contains little suspended sediment, the water tends to scour downstream riverbeds and erode riverbanks. Further, the change in flow rate over the daily cycle of a hydroelectric dam can lead to erosion of sandbars and other downstream structures. Dissolved oxygen content in the water released from the dam may be lower than normal, which can impact downstream flora and fauna, and temperature differences between the water held in the reservoir and the downstream water flow can also have a negative impact on biological populations downstream.
In addition to affecting plant and animal populations, hydroelectric dams may also adversely affect human populations in the area. Such projects may require the relocation of persons living in the area where the reservoirs are planned. In many places around the world, this can result in the loss of important cultural or ancestral lands. Further, in some such projects historically important sites have been lost.
The present invention provides a novel device for producing hydroelectric power that minimizes the disadvantages described above. These and other advantages of the present invention will become clear upon reading the description of the present device, below.


Provided are methods for optimizing presentation of additional items on web page based on item already presented on the web page. A method can include identifying first set of templates. The method can further include, for each of first plurality of requests, selecting first template, selecting first item, transmitting the first template to first client computer, and receiving interaction data from the first client computer specifying one or more interactions with the first template. The method can further include analyzing the interaction data to determine performance metric for each of the first set of templates and replacing at least one or more of the first set of templates and the first item. The method can further include, for each of second plurality of requests, selecting second template, selecting second item, and transmitting the second template to the second client computer. Presentation of additional items can be optimized remotely and automatically.

Conventionally, identifying and presenting additional items on a web page, where the additional items are associated with a base item already displayed on the web page is a very time consuming effort. In some cases, a user must locate the additional items on their own. In other cases, the website must correlate an additional item with the base item. In addition, presenting the additional items require the website to reprogram their layout every time the website makes a change. Thus, integration of additional items can require large amounts of programming on the website. In some examples, the additional items are not presented in an optimal manner for user experience, identification, and interaction. Because of the large amount of analysis needed, merchant's systems often offer generic, suboptimal additional items to customers. Embodiments of the disclosure herein address these and other problems, individually and collectively.

This patent is subject to a terminal disclaimer.


A fan housing (184) is provided for accommodating a fan (154) rotating about a central axis (500). The fan housing comprises: an inlet (212); a diffuser (202); an inner diameter (ID) surface (200, 210) facing the central axis; and an outer diameter (OD) surface (240) facing away from the central axis. A rim (220) at the inlet has a plurality of apexes (231) and a plurality of nadirs (233).

The disclosure relates to HVAC fan inlets. More particularly, the disclosure relates to fan inlets for HVAC fans receiving inlet flows that are not circumferentially uniform.
A typical residential climate control (air conditioning and/or heat pump) system has an outdoor unit including a compressor, a refrigerant-air heat exchanger (coil), and an electric fan for driving an air flow across the heat exchanger. The outdoor unit will often include an inverter for powering the compressor motor and/or fan motor.
In one basic outdoor unit configuration, the outdoor unit has a generally square footprint with the heat exchanger wrapping around four sides and three corners of that footprint between two headers. The compressor is positioned within a central cavity surrounded by the heat exchanger on a base of the unit. A service panel of the housing is mounted aligned with the gap and carries the inverter. The fan is mounted atop the outdoor unit and draws air inward through the heat exchanger to the central cavity and then exhausts it upward.


An instructional method of an electronic keyboard includes the following steps: obtaining a playing script, wherein the playing script is generated by a recording electronic keyboard; the recording electronic keyboard generates the playing script according to a pressed second key and the time of pressing the second key, and the playing script is used for indicating a corresponding relationship between a to-be-pressed key and the time of pressing the to-be-pressed key; controlling an indicator light on the first key of the instructional electronic keyboard to be turned on/off according to the playing script. In this implementation mode, a user can be prompted for the key by an indicator light on the electronic keyboard, which facilitates the user to learn the electronic keyboard.

The electronic keyboard is an electronic instrument having an adjustable volume for sound. The electronic keyboard has a wide range of sounds and chords that can give an instrumental performance, using the various keys and chords that can mimic the sound of an orchestra. The fact that a keyboard with these capabilities can perform this type of music is enormously expressive. Furthermore, the electronic keyboard can also imitate a variety of timbres and even produce sounds (e.g. chorus, wind and rain sounds, synthetic sound, and others) that conventional musical instruments cannot produce. When playing a solo, the electronic keyboard can optionally cooperate the rhythm accompaniments such as the sounds of percussion instruments, which is suitable for playing modern music with strong rhythmicity. Moreover, the electronic keyboard is provided with an effect unit (such as reverberation, echo, tenuto), a vibrato unit, a modulation unit, and other multifunctional devices, which can easily play the various emotive expressions.
However, the keyboard of prior art, has problems. Ordinary people need to spend a great deal of money and time on learning how to operate an electronic keyboard. For example, it takes a lot of time and effort to go to music lessons, which directly contributes to lack of learning efficiency.

Instructional method and system of an electronic keyboard, instructional electronic keyboard, and a storage medium


Reinforced hollow for a wind turbine tower comprising a lower ring (2) that determines an opening (3) for the installation of an access door (not represented) inside the tower (1). The hollow incorporates at least one structural element (4) that is fastened on both sides of the opening (3) of the tower's lower ring (2), providing the rigidness necessary to attach a door and permit the reduction of the thickness of the ring by 10-20%.

Conventional wind turbines comprise a tower firmly anchored to the ground, a nacelle at the top of the tower, and a rotor equipped with at least one blade. Recent tendencies in wind turbine construction entail increased power and towers of greater height.
Wind turbine towers are constructed in sections, which comprise flanges and rings, that determine a thickness of 15-60 mm depending on the height of the tower and the rotor installed in the wind turbine. Each section is coupled to the adjacent section (upper and/or lower) by flanges that are bolted together.
The lower part of the wind turbine tower has an access door that enables workers to enter the wind turbine to undertake maintenance tasks. This access door is installed in a hollow or through opening made into the lower ring of the tower. The problem addressed here is the loss of ring strength and rigidness when this hollow is made.
Wind turbine tower manufacturers normally tend to reinforce this area with frames for the door or by increasing the thickness of the ring in the area, but this extra rigidness proves complex and expensive to produce.
An example of solutions of this sort is described in patent CA 2464623, which claims a structural member (frame) that is welded onto the hole made on the lower part of the tower to accommodate a door.
Other solutions are known such as the one described in patent EP 1856410, which proposes a lower ring manufactured in two parts onto which a door frame is mounted so that one of the parts of the ring, the one onto which the door will be mounted, will be thicker than the other part of the ring. This thus permits a thinner frame to be installed depending on the increase in ring thickness. However, this solution is inefficient, since it substantially increases the weight and mass of this lower tower ring.


A magic compass that gives the illusion it defies the laws of nature, providing usage as an aid for locating the direction of prayer as well as a novel promotional device for companies, having a magnetized compass needle (16) which is attached via a linking means to a non-magnetic pointer (22). This linking means, which can be rigid (11) or non-rigid (29), allows the non-magnetic pointer (22) to be angularly displaced from the magnetized compass needle (16). This linkage also provides the means for the non-magnetic pointer (22) to rotate and pivot freely via the inertia of the magnetized needle (16). A partition (20) hides the magnetized needle (16) below, and simultaneously creates a compass face for the non-magnetic pointer above. The non-magnetic pointer (22) is designed and shaped to appear identical to a true magnetized compass needle (32).

We are all aware of the industry, which is comprised of magicians and their magic tricks. Magic is an age-old art, which can be traced back to time immemorial. In the New Webster's Dictionary, magic is defined as: ("The feigned art of influencing nature or events by occult means; sorcery; charm.") A magician is defined as: ("one skilled in magic; a conjurer.")
One of the most famous magicians of the past century was Harry Houdini. He was famous for his ability to escape from almost any situation. In fact he received a U.S. patent in 1921, U.S. Pat. No. 1,370,316, for a special diving suit. From this suit he was able to escape while handcuffed, chained and submerged in water. There is a vast array of special equipment, which enables the magician to perform his magic tricks. These tricks consist of normal everyday items that have been modified in a hidden way not visible to the human eye, in order to give the impression or illusion to the viewer, that magic, i.e. a process that defies and goes against the laws of nature, is taking place. Another term for this magical process is "sleight of hand". In the Webster's Dictionary, "sleight of hand" is defined as: "artful trick, skill of hand." In other words, we know that there really isn't any "magic" taking place, but we are not able to see how the magician seemingly manipulated the laws of nature. We are left with the mystery of the illusion.
The present invention relates to a compass that instead of being bound by the laws of physics to point only North, can be manufactured in a specific manner to give the illusion that it defies the laws of nature, and can "magically" point in any "other" direction. These "other" directions are for the purpose of the illusion, and not necessarily to specify a specific geographic location. This invention is useful for the entertainment industry that is comprised of magicians, and magic trick manufacturers.
In its other embodiments, my invention will also provide an important usage as a unique promotional aid for companies, a new item for the industries of souvenir and greeting card manufacturers, and a very special device for the worshippers of those religions who need to face in a specific geographic direction when praying. As will be explained further on, there is no limitation to the usefulness of this device due to its novelty.
This invention in its most preferred embodiment has usefulness to the magician trade to portray the art of magic by means of the "slight of hand" techniques practiced by professional magicians. In an example of this technique, the magician would display a generic compass of known type, and show how it follows the laws of physics by always re-aligning itself with the magnetic north pole. During this display, the magician would use the "slight of hand" technique and substitute the north-pointing compass with my magic compass, which will appear identical to the first compass in size and design. He would then display how the compass is no longer bound by the laws of physics and is now pointing in another direction, yet continuing to function like a normal compass. The magician has now proven that he has manipulated the laws of nature.
Another purpose of my invention is to supply a very unique item, which due to its novelty and mystery, will be purchased by companies, and organizations for promotional usages. All companies are in need of promotional gadgets that will bring attention to their company and their products or services. The most well known item in usage today as a promotional tool is the ink pen. Pens that are stamped with the company's name and logo are distributed freely to its customers and business affiliates. Unfortunately, a pen has no novelty, and when the ink is used up, the pen is discarded along with the company's logo. My invention will supply the most original and unique promotional item for these companies and corporations. For example, the South Trust Bank will wish to give to its patrons, a miniature "South Trust Bank Compass" which always points South, i.e. the direction which is the name of the Bank. Such a compass, containing the Bank's emblem embossed on its face, and seemingly defying the laws of nature by always pointing South, shows that the South Trust Bank gives service that is beyond the level of nature. This invention, through its combination of attributes, i.e., a) a compass—being a useful instrument, b) its novelty—by seemingly defying the laws of nature and pointing in the direction of the bank, and by c) attaching it to a key chain, which will enable it to be carried everywhere by the patron, will make my invention the most effective promotional device. Also, unlike a pen, it will never be "used up" and discarded. Another example would be for the Southern Comfort Co. to attach a miniature Southern Comfort Compass on the bottle cap of its whiskey thereby portraying that just as their product surpasses nature in its quality, and taste, they have a very special compass that is compelled to follow suit by pointing South, which is the global direction that is related to the name of their company. In both of the above examples, the direction South is not indicative of a geographic destination, but only to the name of the company as is relevant in advertising.
Another usage for this magic compass is as a novelty item to be introduced to the Greeting Card Industry for a new line of greeting cards. For example, a very small inexpensive model of a compass pointing South would be embedded into the card with the following poem: "When thinking of you, I bought a compass . . . to point me in the right direction, but wonders of wonders the laws of mother nature are broken, the cause must have been my affection." Here we demonstrate how one's affection is so strong that even his compass is affected and acts in a way that is beyond nature. Another example for the Greeting Card Industry would be a compass designed to point South with the following poem: "This compass card that I bought for you has changed mother nature's pattern, instead of pointing "N" for North, it now points "S" for Saturn." This new "magic compass greeting card" will supply the industry with a very special new line of cards, and the purchaser will receive a very unusual gift along with his card. An appropriate poem will accompany the card as is relevant to the direction that the compass is pointing. Of course, a variety of cards would be manufactured to cover the entire spectrum of holidays and birthdays etc.
In the last two examples, my invention finds usage as a very powerful promotional item and in the last example, a new line of greeting cards for the billion-dollar greeting card industry.
Another usage for my magic compass would be as a unique souvenir. Throughout the world, wherever travelers and tourists go, there are stores selling souvenirs, which are designed to serve as a memorable to the place that the tourist has visited. An example of this is a T-shirt with the name of the country or state printed on it. Sometimes we have seen pencils and other items carrying the name of the country or place that the tourist has visited. My invention will add a very unique souvenir item to these stores, which are located at highway stops, national parks or museums. For example; someone driving across country from the East coast to the West, would be very happy to by a souvenir called the "Wild Wild West" Compass. The store owner has provided a very unique souvenir which contains novelty by virtue of its "defying the laws of nature", and by always pointing West. An appropriate picture or logo would be printed on the face of the compass.
Another purpose of my invention is to supply an aid for worshippers of specific religions, who during their prayers need to face in a specific direction. For example, those of the Jewish faith are required to face Jerusalem three times each day while reciting their prayers. People who are outside of their homes or away from their normal house of worship are often in doubt as to the correct direction to face while praying.
An invention that attempts to fulfill this need is found in IL patent 103,686 to Hadar and Erez (1992). This invention is not in the compass, but rather is an invention that is comprised of an ordinary north-pointing compass, unchanged and readily available in any store. This generic compass of known type is set into a box with numbers ranging from 0–360 degrees surrounding the compass in a circular manner, and representing the lines of longitude of the globe. On this box in which the compass is attached, an arrow is painted. The difficulty in using this device, is that each time one wishes to find their direction of prayer, they need to a) hold the box, b) wait for the visible north-pointing needle to find magnetic north, c) then, manually rotate this box so that the geographic place of their origin, which is expressed in degrees of longitude, is opposite this north-pointing magnetic needle. Then they must look at the stationary painted arrow to see in which direction it is pointing. Each time that this device is put down, one must start all over again with the above steps in order to find their desired destination.
Since the above invention utilizes a regular north-pointing compass, it needs to be set into a box, which will contain all of the longitudal numbers on one side, and the names of the geographic destinations on the lid. This creates a very bulky mechanism to be carried from place to place. Also, since the compass it contains is of known type, always pointing north, one must follow all of the above steps as mentioned above in order to find their direction of prayer. The process that is required to operate this device may prove difficult for those worshippers who are less educated, and also prove to be inconvenient to others who will need to complete this process each and every time the device is handled. Also, it would be a great advantage to have a compass that has the added novelty of being magical and always pointing automatically in the direction that is considered to be holy by the worshippers and their religion. This would reaffirm their belief that the place of their prayers is truly holy, since their compass is compelled to point there automatically. The above device can not do this since it only displays a regular north-pointing compass.
Other types of compass inventions have been proposed to help locate the direction of prayer for Moslems who needs to face towards Mecca. For example, DE patent 3412777A1 to Haag (1985), CH patent 607904 to Kamoo (1978), EP patent 60814 to Benhardt (1982), and CH patent 613832 to Mozer (1979).
In each of the above patents, we find various embellishments on the generic north-pointing compass as cited above in the IL patent. In each case, the compass box must be manually rotated in order to align the north-pointing magnetic needle with the name or symbol of the person's geographic location. Also, all of these devices cannot apply the added novelty of magic, since they all contain a visible working north-pointing compass. My previous patent application U.S. Ser. No. 09/845,834 filed (May 1, 2001) to Ashin, and, abandoned in (2002), is enclosed here in this application.
Four more devices, U.S. Pat. No. 5,546,310 to Ehdaie et al (1996), U.S. Pat. No. 5,721,713 to Bornand (1998), U.S. Pat. No. 6,185,157 to Farine (2001), and U.S. Pat. No. 5,790,477 to Hauke (1998) are also used to locate Mecca or some other predetermined geographic location but, they all work via electronic circuitry and some of them utilize antennas. Also, they do not have any appearance to the generic compass of known type and therefore they are unable to provide the novelty of magic with regard to a normal compass. In addition, orthodox worshippers of the Jewish faith are forbidden to operate and even to handle electronic devices on their Sabbath (Saturday) and Holidays.
All of the above compass devices heretofore known, which are meant to locate a predetermined geographic locality for prayer, suffer from a number of disadvantages:
(a) They are all, (excluding the electronic devices), normal generic magnetic north-pointing compasses, thereby unable to supply the added novelty and advantage that "magic" is taking place. For worshippers of various religions who need a device for finding their place of prayer, these devices lack the mystic novelty that their compass is defying the laws of nature by pointing "magically" in the direction of their prayers.
(b) Their usage proves to be difficult. Each time they are handled, one must first find magnetic north, and then they must rotate the entire device until the north pointing magnetic needle is lined up with a name of town, symbol or some other geographic designation. Once this has been completed, the user must then look at a painted or some other stationery pointer to see in which direction to face for their prayers.
(c) Each and every time that one wishes to use the above devices, one must go through the entire three step process of holding, re-aligning, and then looking for the painted stationery pointer as stated above.
(d) Some of the devices need to be attached to a box-like structure or to have other replaceable parts available for carrying. These parts are meant to be interchangeable and necessary to help the locating process from a wider variety of geographic locations. This creates a bulky item, which proves to be difficult and uncomfortable to carry.
(e) The remaining devices used for locating predetermined geographic locations are not compasses but rather compass-like devices that operate through the usage of electronic circuitry and antennas. Besides not having the added advantage of operating in a magical way as stated above, but being electric, they are forbidden to be used and even handled by orthodox worshippers of the Jewish faith on their Sabbath (Saturday) and Holidays.


A food container for cooking through use of a microwave oven includes a container adapted to contain food and having a hole and a pressure regulation valve attached to the food container to close the hole. The pressure regulation valve includes a cover film having an area sufficient to cover the hole, an adhesive layer applied over the surface of the cover film facing the food container, and a separator film disposed between the adhesive layer and the food container and having an area larger than that of the hole but smaller than that of the cover film. When food contained in the container is cocked in a microwave oven, the food is heated so that moisture is produced from the food. Until the vapor pressure within the food container reaches a predetermined level, the pressure regulation valve remains closed. When the vapor pressure within the food container reaches the predetermined level, the cover film partially separates from the food container in order to relieve the vapor pressure. The pressure regulation valve may include a gas-permeable film for preventing hot liquid from spouting from the hole of the container.

1. Field of the Invention
The present invention relates to a food container suitable for cooking through use of a microwave oven.
2. Description of the Related Art
Japanese Patent Application Laid-Open No. 6-329179 discloses a food container suitable for cooking through use of a microwave oven. As shown in FIGS. 1A-1C, the food container has a small hole 1, and a circular cover film 2 is attached to the container via an adhesive layer 3 in order to cover the hole 1. In the adhesive layer 3 is formed a triangular non-adhesive area 4. In this way, the small hole 1, the cover film 2, and the adhesive layer 3 constitute a pressure regulation valve 5.
When the food container containing food therein is cocked in a microwave oven, the food is heated so that moisture is produced from the food. Until the vapor pressure within the food container reaches a predetermined level, the pressure regulation valve 5 remains closed. When the vapor pressure within the food container reaches the predetermined level, as shown in FIG. ID, the sheet 2 partially separates from the food container in order to relieve the vapor pressure. Thus, the food is cooked in a desirable manner. Also, the package container is prevented from bursting due to the vapor pressure.
However, in the conventional food container, the inner circumferential surface 3a of the adhesive layer 3 is exposed to the atmosphere within the container containing a large amount of moisture. Therefore, during long-time storage, the adhesive force of the adhesive layer 3 may be deteriorated, resulting in improper operation of the pressure regulation valve. Further, chemicals contained in the adhesive layer 3 may dissolve and enter the interior of the container, possibly imparting an odor to the food.
In addition, if food contained in the food container produces liquid during cooking, the liquid may spout through the hole and dirty the interior of a microwave oven.

Food container for cooking with microwave oven


A low profile electrical distribution center comprises a plurality of thin bus assemblies that are stacked one upon another. Each bus assembly comprises stamped metal circuit components having planar bus portions sandwiched between thin flexible upper and lower sheets of insulation material that are bonded together. The stamped metal circuit components have male blade terminals that extend up or down from the bus portions. The thin flexible sheets of insulation material are die cut to facilitate manufacture and assembly of the stamped metal circuit components from a one piece stamped metal blank.

U.S. Pat. No. 5,023,752 granted to Gary C. Detter et al. Jun. 11, 1991, discloses an electrical power distribution center that comprises a bus plate assembly in the form of a plurality of vertically stacked circuit layers that eliminate or reduce the need for splices in the conductors of wiring harnesses. Each circuit layer comprises a plurality of stamped metal circuit components that are seated in tracks formed in the surface of an electrical insulating board. The stamped metal circuit components include male blade terminals that are perpendicular to the electrical insulating board. These male blade terminals project through slots extending through one or more of the electrical insulating boards.
The circuit layers are stacked vertically and fastened inside a two-part housing by a plurality of bolts. When the circuit layers are fastened in place, some male blade terminals project through slots in bottom of the lower housing part to provide socket connectors for wiring harnesses. Other male blade terminals project upwardly from the stack of circuit layers and have double ended female terminals attached to them. Electric and electronic components are then plugged into the top of the top housing part and the double-ended female connectors located below the top. A detachable cover is then secured in place to protect the electric and electronic components that are plugged into the top of the housing.
This electrical power distribution center arrangement has been used successfully by the assignee of this invention. However, the vertically stacked arrangement of circuit layers is cumbersome and expensive to manufacture and assemble. Moreover, the vertically stacked arrangement of several circuit layers require substantial vertical space to meet terminal density requirements resulting in a high profile for the electrical power distribution center.
U.S. Pat. No. 5,207,587 granted to Brian D. Hamill et al. May 4, 1993, discloses an electrical distribution center that has an improved bussing arrangement. The Hamill electrical distribution center has a main bus plate assembly that comprises a plurality of stamped metal circuit components that are insert molded in an insulation board. These stamped metal circuit components include several male blade terminals that project outwardly of the insulation board and that include wire-receiving slots. The main bus plate assembly is sandwiched between upper and lower auxiliary bus plate assemblies of the type that are disclosed in U.S. Pat. No. 4,684,765 granted to Lawrence R. Beck et al. Aug. 4, 1987. Each of these bus plate assemblies include a plurality of wire circuit components in an insulated routing board that has slots extending through it.
This electrical distribution center also has been used successfully by the assignee of this invention. While the main bus plate and auxiliary bus plate assemblies is less cumbersome than the vertically stacked circuit layers of the Detter et al. '752 arrangement, the main bus plate assembly is still expensive to manufacture and assemble. Moreover, the combination of the main bus plate and auxiliary bus plate assemblies still require substantial vertical space to meet terminal density requirements resulting in a high profile for the electrical distribution center.

Low profile electrical distribution center and method of making a bus subassembly therefor


A method and an apparatus for elevator group control, capable of performing the elevator car allocation control with the evaluation characteristics and the control parameters which are most appropriate for a unique situation of each building. In the apparatus, a hall call allocation control to determine a most appropriate one of the elevator cars to respond to a hall call produced at one of the destination floor, is performed by carrying out evaluations in accordance with a given traffic demand of the elevator system; and the control parameters to be utilized in carrying out the evaluations, are determined in accordance with a response resulting from the hall call allocation control and the given traffic demand.

1. Field of the Invention
The present invention relates to a method and an apparatus for elevator group control by which an elevator system including a plurality of elevator cars and a plurality of destination floors are controlled.
2. Description of the Background Art
Recently, an elevator system including a plurality of elevator cars and a plurality of destination floors is equipped with a microcomputer to administer efficient and speedy allocations of elevator cars to hall calls produced at various destination floors, so as to improve the efficiency of elevator utilization and the quality of service.
Namely, in such an elevator system, when a hall call is produced at a certain floor, an elevator car which is most appropriate to respond to this hall call is selected from the plurality of elevator cars of the system, while the other elevator cars are prohibited to respond to this hall call.
More recently, a group controlled elevator system has been developed in which an elevator group control apparatus can perform the elevator car allocation control by gathering so called elevator car call response registration data regarding hall calls to which each elevator car has responded, so as to apprehend traffic demands among the floors of each building, and by utilizing these data to the elevator car allocation control, so as to account for a unique situation characteristic to each building. In this type of the elevator car allocation control, various evaluation characteristics are set up in accordance with the characteristics of each building, evaluation values for these evaluation characteristics are estimated, the evaluation values are multiplied by appropriate weight factors functioning as control parameters and then summed to obtain a total evaluation for each elevator car, and the most appropriate elevator car is selected from the plurality of elevator cars in accordance with the total evaluations obtained for the plurality of elevator cars.
However, because the relative importance of each of the evaluation characteristics for the elevator car allocation control changes radically depending on the traffic situation, so that ideally the control parameters have to be selected, appropriately in accordance with the traffic situation. Such an optimization of the control parameters in accordance with continuously changing traffic situation of the elevator system has conventionally been impossible.
Also, because the evaluation characteristics for the elevator car allocation control varies widely depending on various characteristics of each building, such as a type of usage and a type of tenant, so that the evaluation characteristics have to be selected in accordance with such characteristics of each building, an automatic setting of the evaluation characteristics has conventionally been impossible. Conventionally, the evaluation characteristics are selected by each building's administrator, and then numerous simulations are performed in order to determine the appropriate control parameters before the actual use of the elevator system begins. Thus procedure requires an enormous number of simulations to be performed, and moreover, the results of such simulations are still not capable of reflecting all the characteristics of each elevator system, such that it has been possible that the intended efficiency and speediness may not be obtained by the selected control parameters.

Method and apparatus for elevator group control with learning based on group control performance


A control apparatus for controlling a vehicle drive apparatus including: (i) a power transmitting member; (ii) a differential mechanism which has a first element connected to an engine, a second element connected to a first electric motor, and a third element connected to a second electric motor and the power transmitting member; (iii) an automatic transmission constituting at least a part of a power transmitting path between the power transmitting member and a drive wheel; and (iv) a differential-state switching device operable to selectively place the differential mechanism in its differential state in which the second and third elements are rotatable at respective different speeds, and in its non-differential state in which the second and third elements are not rotatable at respective different speeds. The control apparatus includes a switching device controller operable to cause the differential-state switching device to place the differential mechanism in the differential state, at least during generation of an electric energy by the first electric motor and/or second electric motor while the power transmitting path is being disconnected. Also disclosed is a vehicle drive system including the above-described control apparatus.

1. Field of the Invention
The present invention relates in general to a control apparatus for controlling a vehicle drive apparatus which is equipped with a differential mechanism serving as a speed variable transmission owing to its differential action. More particularly, the invention is concerned with techniques for improving an efficiency of electricity generation while a drive power transmitting path is being disconnected.
2. Discussion of Related Art
There is known a hybrid vehicle drive apparatus including: (i) a power transmitting member; and (ii) a differential mechanism having a first element connected to an internal combustion engine, a second element connected to a first electric motor having an electricity generating function, and a third element connected to the power transmitting member and a second electric motor which is connectable to the first electric motor through an electric path, as disclosed in JP-2000-238555A, JP-2003-130203A and JP-2003-127681A. The differential mechanism of the drive apparatus serves as a power distributing mechanism for distributing a drive power or force of the engine to the first electric motor and the power transmitting member. The differential mechanism is constituted by a planetary gear set whose differential action permits a major portion of the drive force of the engine to be mechanically transmitted to drive wheels and also permits the rest of the drive force to be electrically transmitted from the first electric motor to the second electric motor through the electric path, so as to serve as a speed variable transmission capable of electrically changing its speed ratio, thereby making it possible to drive the vehicle with the engine kept in an optimum operating state with a reduced fuel consumption. Further, as other prior arts relating to the present invention, JP-H09-98516A discloses a technique for reducing a fuel consumption of a hybrid vehicle, and JP-2001-41073A discloses a technique for improving an efficiency of an electricity generation performed by a generator which is driven by a vehicle engine. Specifically, JP-2001-41073A teaches releasing a clutch during the electricity generation, for avoiding of transmission of a rotary motion of the engine to a fluid coupling (torque converter) which is disposed on one of opposite sides of the clutch remote from the engine, so as to improve the electricity generation efficiency.
In the above-described hybrid vehicle drive apparatus, when the electricity generation is intended with the drive apparatus being placed in its non-driving position such as a neutral position, the rotational speed of the second element has to be increased to such a value that permits the rotational speed of the power transmitting member to be zeroed. This means that the rotational speed of the first electric motor connected to the second element can not be freely determined, namely, the first electric motor as a generator can not be operated at such an operating point that maximizes the efficiency of the electricity generation. That is, in the above-described hybrid vehicle drive apparatus, there is a limit to improvement of the generation efficiency. In view of this, there has been a demand for a control apparatus capable of maximizing the efficiency of the electricity generation as intended while the drive apparatus is placed in the non-driving position, in the vehicle drive apparatus equipped with the differential mechanism serving as the speed variable transmission owing to its differential action.

Control apparatus for controlling vehicle drive apparatus, and vehicle drive system including the control apparatus


The present invention intends to provide a process for producing CF3CF3 with good profitability using CF3CHF2 containing a compound having chlorine atom within the molecule, and use thereof.

1. Technical Field of the Invention
The present invention relates to a process for producing hexafluoroethane, comprising a step of reacting a gas mixture containing pentafluoroethane and a compound having chlorine atom with hydrogen fluoride in the gaseous phase in the presence of a fluorination catalyst to fluorinate the compound having chlorine atom and a step of reacting the gas mixture containing pentafluoroethane and the fluorinated compound with fluorine gas in the gaseous phase in the presence of a diluting gas, and also relates to the use thereof.
2. Background Art
Pentafluoroethane (hereinafter referred to as xe2x80x9cCF3CHF2xe2x80x9d) is used, for example, as a refrigerant for low-temperature use or a starting material for the production of hexafluoroethane (hereinafter referred to as xe2x80x9cCF3CF3xe2x80x9d).
For the production of CF3CHF2, for example, the following methods have been heretofore known:
(1) a method of fluorinating perchloroethylene (CCl2xe2x95x90CCl2) or a fluoride thereof with hydrogen fluoride (see, JP-A-5-97724 (the term xe2x80x9cJP-Axe2x80x9d as used herein means an xe2x80x9cunexamined published Japanese patent applicationxe2x80x9d), JP-A-6-506221, JP-A-7-76534, JP-A-7-118182, JP-A-8-268932 and JP-A-9-511515),
(2) a method of performing hydrogenolysis of chloropentafluoroethane (CClF2CF3), and
(3) a method of reacting a fluorine gas with a halogen-containing ethylene (see, JP-A-1-38034).
When these methods for producing CF3CHF2 are used, the objective CF3CHF2 contains a compound having chlorine atom within the molecule as main impurities. The compound having chlorine atom within the molecule includes a compound having one carbon atom within the molecule, such as chloromethane, chlorodifluoromethane and chlorotrifluoromethane, a compound having two carbon atoms within the molecule, such as chloropentafluoroethane, dichlorotetrafluoroethane, chlorotetrafluoroethane and chlorotrifluoroethane, and an unsaturated compound such as chlorotrifluoroethylene.
In the case of producing CF3CF3 by a direct fluorination reaction of reacting CF3CHF2 with a fluorine gas (F2), if CF3CHF2 contains the compound having chlorine atom within the molecule, chlorine, hydrogen chloride, chlorine fluoride or different kinds of chlorofluorocarbons are generated in the reaction with fluorine gas. Even when hydrofluorocarbons (HFC) or perfluorocarbons (PFC) are contained in CF3CHF2, there arises no particular problem, however, for example, chloromethane (CH3Cl) or chlorodifluoromethane (CHClF2) reacts with fluorine gas to produce chlorotrifluoromethane (CClF3). The objective CF3CF3 and chlorotrifluoromethane form an azeotropic composition, therefore, CClF3 is difficult to remove even by performing distillation, adsorption for purification, or the like. Accordingly, in the case of reacting CF3CHF2 with a fluorine gas to produce CF3CF3, the amount of the compound having chlorine atom within the molecule contained in CF3CHF2 should be reduced as much as possible.
According to conventional production methods for CF3CHF2, the total amount of the compound having chlorine atom within the molecule is sometimes as high as about 1 vol %. Therefore, a distillation operation is repeated for removing these compounds contained in CF3CHF2 and elevating the purity of CF3CHF2, however, this has such a problem that the distillation cost increases, the distillation loss is caused, the profitability is bad and some compounds having chlorine atom within the molecule form an azeotropic mixture or an azeotrope-like mixture with CF3CHF2 and are very difficult to remove only by the distillation operation. In particular, chloropentafluoroethane (hereinafter referred to as xe2x80x9cCClF2CF3xe2x80x9d) is usually contained in CF3CHF2 in a concentration of thousands of ppm or more but since an azeotropic mixture is formed by CF3CHF2 and CClF2CF3, the separation is hardly attained by distillation which is a commonly used separation and purification method.
For separating CClF2CF3 contained in CF3CHF2, various methods have been proposed, for example,
(1) a method of adding a third component to a mixture of CF3CHF2 and CClF2CF3 and performing the extractive distillation (see, JP-A-6-510980, JP-A-7-133240, JP-A-7-258123, JP-A-8-3082, JP-A-8-143486 and JP-A-10-513190),
(2) a method of removing CClF2CF3 contained in CF3CHF2 using an adsorbent (see, JP-A-6-92879 and JP-W-8-508479 (the term xe2x80x9cJP-Wxe2x80x9d as used herein means an xe2x80x9cunexamined published international patent applicationxe2x80x9d)), and
(3) a method of converting CClF2CF3 contained in CF3CHF2 into CF3CHF2 in the presence of a hydrogenation catalyst (see, JP-A-7-509238, JP-A-8-40949, JP-A-8 -301801 and JP-A-10-87525).
However, these methods have a problem, that is, the method of (1) requires a step of recovering the third component from the mixture of CClF2CF3 and the third component, the method of (2) requires a step of regenerating the adsorbent, and the method of (3) suffers from reduction in the catalytic life due to hydrogen chloride produced.
The present invention has been made under these circumstances and the object of the present invention is to provide a method for producing CF3CF3 with good profitability using a gas mixture containing CF3CHF2 and a compound having chlorine atom within the molecule in the method for producing CF3CF3 which is used as an etching or cleaning gas in the process of producing a semiconductor device, and also provide a use thereof.
As a result of extensive investigations to solve the above-described problems, the present inventors have found that in the method for producing CF3CF3, when a gas mixture containing CF3CHF2 and a compound having chlorine atom within the molecule as impurities is reacted with hydrogen fluoride in the presence of a fluorination catalyst to convert CClF2CF3 which is contained in the gas mixture, into CF3CF3 and then performing a direct fluorination reaction of reacting the resulting gas mixture containing CF3CHF2 and CF3CF3 with a fluorine gas in the gaseous phase in the presence of a diluting gas, the above-described problems can be solved. The present invention has been accomplished based on this finding. The present invention provides a process for producing CF3CF3 and use thereof, described in [1] to [19] below.
[1] A process for producing hexafluoroethane, comprising the following two steps:
(1) a step of reacting a gas mixture containing pentafluoroethane and a compound having chlorine atom with hydrogen fluoride in the gaseous phase in the presence of a fluorination catalyst to fluorinate the compound having chlorine atom; and
(2) a step of reacting the gas mixture containing pentafluoroethane and the fluorinated compound obtained in the step (1) with a fluorine gas in the gaseous phase in the presence of a diluting gas.
[2] The process for producing hexafluoroethane as described in [1], wherein the compound having chlorine atom is at least one compound selected from the group consisting of chloromethane, chlorotrifluoromethane, chloropentafluoroethane, dichlorotetrafluoroethane, chlorotetrafluoroethane, chlorotrifluoroethane and chlorotrifluoroethylene.
[3] The process for producing hexafluoroethane as described in [1] or [2], wherein the total amount of the compound having chlorine atom contained in the gas mixture of the step (1) is 1 vol % or less.
[4] The process for producing hexafluoroethane as described in [1] or [2], wherein the total amount of the compound having chlorine atom contained in the gas mixture of the step (1) is 0.5 vol % or less.
[5] The process for producing hexafluoroethane as described in any one of [1j to [4], wherein in the step (1), the fluorination catalyst is a bulk catalyst obtained by adding indium to an oxide of chromium.
[6] The process for producing hexafluoroethane as described in any one of [1] to [5], wherein in the step (1), the temperature at the reaction with hydrogen fluoride in the presence of a fluorination catalyst is in the range of 150 to 480xc2x0 C.
[7] The process for producing hexafluoroethane as described in any one of [1] to [6], wherein in the step (1), the molar ratio of hydrogen fluoride/organic substance contained in the gas mixture is in the range of 0.5 to 5.
[8] The process for producing hexafluoroethane as described in any one of [1] to [7], wherein a step of removing an acid content containing hydrogen chloride produced is conducted before the step (2).
[9] The process for producing hexafluoroethane as described in any one of [1] to [8], wherein a step of separating chlorotetrafluoroethane and/or chlorotrifluoroethane, and returning the chlorotetrafluoroethane and/or chlorotrifluoroethane separated to the step (1) is conducted before the step (2).
[10] The process for producing hexafluoroethane as described in any one of [1] to [9], wherein in the step (2), the total amount of the compound having chlorine atom contained in the gas mixture is 0.02 vol % or less.
[11] The process for producing hexafluoroethane as described in any one of [1] to [10], wherein in the step (2), the fluorinated compound contained in the gas mixture is mainly composed of hexafluoroethane.
[12] The process for producing hexafluoroethane as described in any one of [1] to [11], wherein in the step (2), the diluting gas is a gas containing at least one selected from the group consisting of tetrafluoromethane, hexafluoroethane, octafluoropropane and hydrogen fluoride.
[13] The process for producing hexafluoroethane as described in any one of [1] to [12], wherein in the step (2), the diluting gas is a gas rich in hydrogen fluoride.
[14] The process for producing hexafluoroethane as described in any one of [1] to [13], wherein in the step (2), the temperature at the reaction of gas mixture containing the fluorinated compound with fluorine gas is in the range of 250 to 500xc2x0 C.
[15] The process for producing hexafluoroethane as described in any one of [1] to [14], wherein in the step (2), the temperature at the reaction of gas mixture containing the fluorinated compound with fluorine gas is in the range of 350 to 450xc2x0 C.
[16] A hexafluoroethane product comprising hexafluoroethane having a purity of 99.9997 vol % or more.
[17] The hexafluoroethane product as described in [16], wherein the content of the compound having chlorine atom is 1 volppm or less and the content of the pentafluoroethane is 1 volppm or less.
[18] An etching gas comprising the hexafluoroethane product described in [16] or [17].
[19] A cleaning gas comprising the hexafluoroethane product described in [16] or [17].
In summary, the present invention provides xe2x80x9ca process for producing CF3CF3, comprising a step of reacting a gas mixture containing CF3CHF2 and a compound having chlorine atom with hydrogen fluoride in the gaseous phase in the presence of a fluorination catalyst to fluorinate the compound having chlorine atom and a step of reacting a gas mixture containing CF3CHF2 and the fluorinated compound obtained by the above-described step with a fluorine gas in the gaseous phase in the presence of a diluting gasxe2x80x9d, xe2x80x9can CF3CF3 product comprising CF3CF3 having a purity of 99.9997 vol % or morexe2x80x9d, xe2x80x9can etching gas comprising the above-described CF3CF3 productxe2x80x9d and xe2x80x9ca cleaning gas comprising the above-described CF3CF3 productxe2x80x9d.
The production process for CF3CF3 and use thereof according to the present invention are described in detail below.
As described above, CF3CHF2 for use in the present invention is generally produced by fluorinating perchloroethylene (CCl2xe2x95x90CCl2) or a fluoride thereof with hydrogen fluoride (HF), and CF3CHF2 contains a compound having chlorine atom derived from the starting material, such as chloromethane, chlorodifluoromethane, chlorotrifluoromethane, chloropentafluoroethane, dichlorotetrafluoroethane, chlorotetrafluoroethane and chlorotrifluoroethane. In order to purify CF3CHF2 containing these compounds to a high purity, known methods by a distillation operation are employed, however, these methods have such a problem that these are not economical since the compound and CF3CHF2 form an azeotropic mixture or an azeotrope-like mixture, the purification by separation is very difficult, the number of stages of the distillation tower or the number of the distillation towers must be increased, and the cost for equipment or energy increases.
In the present invention, the compound having chlorine atom contained in CF3CHF2 as impurities is fluorinated with hydrogen fluoride at an elevated temperature in the presence of a fluorination catalyst and thereby converted into hydrofluorocarbon (HFC) or perfluorocarbon (PFC). For example, in fluorinating CClF2CF3 or chlorotetrafluoroethane contained as impurities in CF3CHF2 using hydrogen fluoride, a reaction shown by the following formula (1) or (2) takes place:
CF3CClF2+HFxe2x86x92CF3CF3+HClxe2x80x83xe2x80x83(1)
CF3CHClF+HFxe2x86x92CF3CHF2+HClxe2x80x83xe2x80x83(2)
The product is HFC or PFC free of chlorine atom, and hydrogen chloride is produced as a by-product.
In the present specification, the gas mixture containing CF3CHF2 and the compound having chlorine atom is sometimes referred to as xe2x80x9cstarting gas mixturexe2x80x9d.
In this fluorination reaction, the compound which is converted into HFC or PFC is chloromethane, chlorodifluoromethane, chlorotrifluoromethane, chloropentafluoroethane, dichlorotetrafluoroethane, chlorotetrafluoroethane and chlorotrifluoroethane. These compounds are usually contained in CF3CHF2 in a total amount of thousands of ppm or more. When the starting gas mixture containing these compounds is reacted with a fluorine gas, the methane-type compounds are converted into CClF3 and the ethane-type compounds are converted into CClF2CF3, therefore, CF3CF3 obtained after the reaction contains CClF3 and CClF2CF3 as main impurities.
CClF2CF3 scarcely reacts with a fluorine gas at low temperatures. However, according to the investigations by the present inventors, for example, at a reaction temperature of 400xc2x0 C., the amount of CClF3 produced by the decomposition of CClF2CF3 is 1 ppm or less when the concentration of CClF2CF3 contained in the starting gas mixture is about 800 ppm or less, and about 2 ppm of CClF3 is produced when the concentration of CClF2CF3 exceeds about 2,000 ppm. CClF3 forms an azeotropic mixture with CF3CF3, therefore, even if the concentration is low, this compound is difficult to remove by an operation of distillation, adsorption for purification or the like. Accordingly, it is preferred that not only a compound which produces CClF3 upon reaction with a fluorine gas is removed from CF3CHF2 as a starting material but also the CClF2CF3 content is reduced to a low concentration as much as possible.
The total amount of the compound having chlorine atom contained in the starting gas mixture for use in the present invention is preferably 1 vol % or less, more preferably 0.5 vol % or less, still more preferably 0.3 vol % or less. If the concentration of the compound having chlorine atom exceeds 1 vol %, the reaction must be performed at a high temperature and the life of the fluorination catalyst is disadvantageously shortened, moreover, a side reaction proceeds at the same time and the productivity decreases.
The fluorination catalyst comprises at least one element selected from the group consisting of chromium, nickel, zinc, indium and garium, and may be a known catalyst such as supported catalyst or bulk catalyst.
In the case of the supported catalyst, carrier is preferably an alumina and/or partially fluorinated alumina, and supporting ratio is preferably 30 wt % or less. In the case of the bulk catalyst, particularly preferred is those containing chromium as main component, and having atomic ratio of nickel, zinc, indium and/or garium to chromium of 0.01 to 0.6. In the present invention, most preferred is a bulk catalyst obtained by adding indium to an oxide of chromium.
In the step of fluorinating the compound having chlorine atom, the reaction temperature is preferably from 150 to 480xc2x0 C. If the reaction temperature exceeds 480xc2x0 C., the reaction is adversely affected, for example, the catalyst deteriorates or a side reaction proceeds, and this is not preferred. Although it may vary depending on the concentration of the compound contained in the starting gas mixture, a preferred reaction temperature can be selected according to the kind of the compound. For example, in the reaction of CClF2CF3 shown in formula (1), the reaction temperature is preferably 400xc2x0 C. or more, and in the reaction of CF3CHClF shown by formula (2), the reaction temperature is preferably 300xc2x0 C. or more.
In the case of a reaction of chlorodifluoromethane (CHClF2) with hydrogen fluoride, a reaction shown by the following formula (3) takes place:
CHClF2+HFxe2x86x92CHF3+HClxe2x80x83xe2x80x83(3)
In this reaction, the reaction temperature is preferably 150xc2x0 C. or more and if the reaction temperature exceeds 400xc2x0 C. or more, a reverse reaction disadvantageously proceeds.
In the step of fluorinating a compound having chlorine atom, the reaction temperature sometimes varies depending on the kind of the compound as described above. Accordingly, in the case where a plurality of compounds are contained and these are different from each other in the optimal reaction temperature region or the concentration of each compound is high, two or more units of reactors are preferably used, though one unit of a reactor is usually sufficient.
The amount of HF used is, in terms of the molar ratio to the organic substance of the starting gas mixture containing CF3CHF2 (HF/organic substance), suitably from 0.5 to 5, preferably from 0.5 to 2. If the molar ratio is less than 0.5, the reaction is hard to proceed, whereas if it exceeds 5, a large reactor is necessary and this is not profitable.
Furthermore, in the step of fluorinating a compound having chlorine atom, the reaction pressure is preferably from atmospheric pressure to 1.5 MPa. If it exceeds 1.5 MPa, the apparatus is disadvantageously required to have pressure resistance or the like.
In the present invention, the reaction with hydrogen fluoride is performed in the presence of a fluorination catalyst using the above-described reaction conditions, and then CF3CHF2, chlorine atom-free impurities mainly comprising HFC or PFC, and hydrogen chloride as a by-product are contained in the reaction product. In the case of CF3CHF2, as the reaction temperature becomes higher, a side reaction with hydrogen chloride more proceeds as shown in the following formula (4):
CF3CHF2+HClxe2x86x92CF3CHClF+HFxe2x80x83xe2x80x83(4)
In the case of containing 1,1,1,2-tetrafluoroethane, a side reaction with hydrogen chloride more proceeds as shown in the following formula (5):
CF3CH2F+HClxe2x86x92CF3CH2Cl+HFxe2x80x83xe2x80x83(5)
Therefore, after the fluorination step of (1), the acid content containing hydrogen chloride produced is preferably removed.
The acid content is removed so as to remove unreacted hydrogen fluoride (excess hydrogen fluoride) and hydrogen chloride as a by-product. Hydrogen fluoride brings about no adverse effect in the direct fluorination reaction step but hydrogen chloride is preferably removed because this product sometimes causes an adverse effect such as production of a chlorine-containing compound or chlorine fluoride as shown in the formula (4) or (5). The step of removing the acid content is performed before the direct fluorination reaction step. Examples of the method for removing the acid content includes:
(1) in the case of containing a large amount of unreacted hydrogen fluoride, a method of introducing an effluent containing the acid content into a distillation tower, extracting hydrogen chloride from the top and extracting organic substance and hydrogen fluoride from the bottom,
(2) a method of contacting the hydrogen chloride produced and unreacted hydrogen fluoride with a purifying agent, and
(3) a method of washing the acid content with water or alkali water.
In the present invention, the method for removing the acid content is not particularly limited and, for example, the method of (3) may be used. The alkali used therein may be an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution or the like. The absorbed hydrogen fluoride may be recovered and reused, and the gas passed through the washing solution is dehydrated using a dehydrating agent such as zeolite.
The gas mainly comprising CF3CHF2 passed through the acid content-removing step sometimes contains as impurities HCFC or CFC which is not completely fluorinated by the reaction with hydrogen fluoride, and in such a case, HCFC or CFC is preferably removed by distilling before the direct fluorination reaction step.
CF3CHF2 and main compounds which may be contained in CF3CHF2 are shown, together with respective boiling points in Table 1.
The gas mainly comprising CF3CHF2 is introduced into a distillation tower, then CF4, CHF3, CF3CF3, CF3CHF2 and CClF2CF3 as the low boiling fraction are extracted from the top of the distillation tower, and CF3CHClF and CF3CH2Cl as the high boiling fraction are extracted from the bottom. The high boiling fraction extracted from the bottom is circulated into the reaction with hydrogen fluoride of the step (1). Here, the total amount of the compound having chlorine atom, which is contained in the distillate mainly comprising CF3CHF2 extracted from the top, is preferably 0.02 vol % or less. The distillate mainly comprising CF3CHF2 is used as a starting material in the direct fluorination reaction with fluorine gas.
The step (2) of reacting the gas mainly comprising CF3CHF2 with fluorine gas is described below.
The step (2) is performed in the presence of a diluting gas and the gas mainly comprising CF3CHF2 is set to a concentration lower than the explosion range. Specifically, the CF3CHF2 concentration at the reactor inlet is preferably set to about 6 mol % or less. The diluting gas is a gas containing at least one selected from the group consisting of tetrafluoromethane, hexafluoroethane, octafluoropropane and hydrogen fluoride, preferably a diluting gas rich in hydrogen fluoride.
The amount of fluorine gas used is, in terms of the molar ratio to CF3CHF2 (F2/CF3CHF2), suitably in the range of 0.5 to 2, preferably in the range of 0.9 to 1.3. The reaction temperature is in the range of 250 to 500xc2x0 C., preferably in the range of 350 to 450xc2x0 C. If the reaction temperature exceeds 500xc2x0 C., the objective CF3CF3 is disadvantageously cleaved to produce CF4 and in the case of containing CClF2CF3 as an impurity, CClF3 is disadvantageously produced due to cleavage of CClF2CF3, whereas if it is less than 250xc2x0 C., the reaction slowly proceeds and this is not preferred.
The method for purifying the gas distilled out from the reaction step of (2) is not particularly limited. The remaining unreacted fluorine gas may be removed by adding, for example, trifluoromethane as HFC and then the residue is distilled to separate, for example, hydrogen fluoride and organic substance. The separated hydrogen fluoride is reused as the diluting gas in the direct fluorination reaction of the step (2) but may also be used as a starting material in the fluorination reaction of (1). The composition of the organic substance separated greatly differs depending on the diluting gas used for the reaction and in the case of using a gas rich in hydrogen fluoride or in the objective CF3CF3, the organic substance obtained contains CF3CF3 as a main component. In the case of using tetrafluoromethane or octafluoropropane as the diluting gas, the gas is purified by again performing distillation. In either case, high-purity CF3CF3 can be obtained by repeatedly performing the distillation operation according to the compositional ratio of the organic substance obtained.
In the distillation for purification of the organic substance, although it may vary depending on the compositional ratio, for example, an inert gas and CF4 as the low boiling fraction are extracted from the top of the first distillation tower and the gas mainly comprising CF3CF3 is extracted from the bottom and introduced into the second distillation tower. Then, an inert gas and trifluoromethane as the low boiling fraction are extracted from the top of the second distillation tower and the gas mainly comprising CF3CF3 is extracted from the bottom and introduced into the third distillation tower to extract high-purity CF3CF3 from the top, thereby performing the purification. The gas containing CClF2CF3 collected from the bottom in the third distillation may be circulated into the reaction step with hydrogen fluoride of (1).
The thus-purified CF3CF3 contains almost no impurities and high-purity CF3CF3 can be obtained. The purity thereof is 99.9997 vol % or more, and 1 volppm or less of the compound having chlorine atom and 1 volppm or less of pentafluoroethane are contained as impurities.
As the analysis method of CF3CF3 having a purity of 99.9997 vol % or more, gas chromatography (GC) using TCD method, FID method (each including the precut method) or ECD method, or an instrument such as gas chromatography mass spectrometer (GC-MS) may be used.
Use of CF3CF3 obtained by the production process of the present invention is described below.
The high-purity CF3CF3 can be used as an etching gas at the etching step in the process of manufacturing a semiconductor device and also can be used as a cleaning gas at the cleaning step in the process of manufacturing a semiconductor device.
In the process of manufacturing a semiconductor device such as LSI and TFT, a thin or thick film is formed using CVD, sputtering or vapor deposition, and the film is etched to form a circuit pattern. In the apparatus for forming a thin or thick film, cleaning for removing unnecessary deposits accumulated on the inner wall of the apparatus, jigs and the like is performed, because the produced unnecessary deposits cause generation of particles and must be removed on occasions so as to produce a film having good quality.
The etching process using CF3CF3 can be performed under various dry etching conditions such as plasma etching and microwave etching, and CF3CF3 may be used by mixing it with an inert gas such as He, N2 and Ar or with a gas such as HCl, O2 and H2 at an appropriate ratio.

Process for producing hexafluoroethane and use thereof

Abstract: In the process of the present invention, a gas mixture containing CF3CHF2 and a compound having chlorine atom within the molecule is reacted with hydrogen fluoride in the presence of a fluorination catalyst, thereby converting CClF2CF3 as a main impurity into CF3CF3, and CF3CHF2 containing CF3CF3 is reacted with fluorine gas in the gaseous phase in the presence of a diluting gas.


The near-universal connection between control panels and monitoring stations is used to transmit status information for non-compatible control panels to connected services systems. In this way, connected services systems can incorporate monitoring and tracking of non-compatible control panels as well as compatible control panels.

Fire alarm systems are often installed within buildings such as commercial, residential, or governmental buildings. Examples of these buildings include offices, hospitals, warehouses, schools, shopping malls, government offices, and casinos.
The fire alarm systems typically include fire control panels (or control panels) that function as system controllers. Fire detection/initiation devices and alarm notification devices are then installed throughout the buildings and connected to the panels. Some examples of fire detection/initiation devices include smoke detectors, carbon monoxide detectors, flame detectors, temperature sensors, and/or pull stations (also known as manual call points). Some examples of fire notification devices include speakers, horns, bells, chimes, light emitting diode (LED) reader boards, and/or flashing lights (e.g., strobes).
The fire detection devices monitor the buildings for indicators of fire. Upon detection of an indicator of fire such as smoke or heat or flames, the device is activated and a signal is sent from the activated device to the control panel. The control panel then initiates an alarm condition by activating audio and visible alarms of the fire notification devices of the fire alarm system. Additionally, the control panel will also send an alarm signal to a monitoring station, which will notify the local fire department or fire brigade.
The monitoring stations will typically monitor multiple fire alarm systems for alarm signals and then notify the proper authorities. Monitoring stations are often required by regulations, making them a standard component of most fire alarm systems, regardless of age or manufacturer of the fire alarm systems' components. These monitoring stations can be administered by a third party company, the same company that provides or manufactures the fire alarm systems, or a public agency, among examples.
The monitoring stations will receive other signals, beyond the alarm signals, from the fire alarm systems. Handshaking signals between the control panels and the monitoring stations are used to confirm the connection status between the fire alarm systems and the monitoring station. Typically, monitoring stations include computer and software systems for receiving, storing, analyzing and displaying connectivity status and fire alarm information based on the signals received from the fire alarm systems. A technician monitors the information and, in the event of a potential fire, informs the local fire department or fire brigade and/or initiates a specified sequence of actions in response to receiving alarm signals for a potential fire.
Typically, building codes, local laws, standards, and/or insurance providers require that the fire alarm systems are periodically tested (e.g., monthly, quarterly, or annually) to verify that the fire detection/initiation and fire notification devices are physically sound, unaltered, working properly, and located in their assigned locations. This testing of the devices is often accomplished with a walkthrough test.
Historically, walkthrough tests were performed by a team of at least two technicians, also known as inspectors. The first technician walked through the building and manually activated each fire detection/initiation such as will artificial smoke while the second technician remained at the control panel to verify that the control panel received a signal from the activated device and/or that the fire notification device properly produced its form of alert. The technicians would typically communicate via two-way radios or mobile phones to coordinate the testing of each device. In some cases, the technicians might even have resorted to comparing hand written notes of the tested devices. After a group of fire detection and fire annunciation devices was tested, the technician at the panel reset the control panel while the other technician moved to the next group of fire detection or fire annunciation devices.
More recently, it has been proposed to use connected services systems to monitor control panels during walkthrough tests, for example. In some cases, the control panels have been given network connectivity to communicate with the connected services systems; in other cases, the technicians have temporarily connected testing computers to the control panels that functioned as gateways. This has allowed the control panels to report status information to the connected services systems, which are typically administered by fire alarm system companies and include, for example, databases for storing historical status information. These connected services systems will also often have remote diagnostic capabilities. As such, connected services systems facilitate the maintenance, compliance and tracking of repairs of fire alarm systems.

Method and system for monitoring fire alarm systems


An apparatus that is usable with a subterranean well includes a safety valve assembly and a pressure/temperature sensor. The safety valve assembly is controllable to selectively isolate a formation of a well from the surface of the well. The pressure/temperature sensor is located in the safety valve assembly to measure a pressure/temperature near the safety valve assembly.

The invention relates generally to a downhole safety valve assembly that has sensing capabilities, such as, for example, a safety valve assembly that has at least one temperature and/or pressure sensor.
A typical subterranean well includes a formation isolation valve, or safety valve, for purposes of providing a failsafe mechanism to isolate one or more downhole formations from the surface of the well. A typical safety valve may be formed from a flapper element that is located inside a tubular string and is biased to close off a central passageway of the string. The flapper element may be opened by a flow tube.
More specifically, a conventional safety valve assembly may include a flapper valve element and a hydraulically-actuated flow tube. When communication is desired between the surface and the formation(s) below the safety valve, the flow tube is actuated to force the flapper valve element open. However, when this communication is no longer desired, the flow tube is actuated to retract, a retraction that allows the flapper element to return to its normally closed position to isolate the formation(s) from the surface of the well.
A difficulty in using the above-described arrangement is that downhole seals, such as seals associated with hydraulic control lines that control movement of the flow tube, may potentially fail. Although safety valve assemblies have been designed to accommodate potential seal failure, an operator at the surface of the well may be unaware of such a failure or the specific type of failure, as the safety valve assembly typically is located far (approximately 10,000 feet or more downhole, for example) from the surface of the well.

Downhole safety valve assembly having sensing capabilities