An interrupt controller includes an interrupt request register for receiving interrupt requests from various peripherals or I/O devices via a set of request lines. A priority resolver is further provided for comparing the priority level of the interrupt lines, latching the lower priority requests in a stand-by mode, and directing servicing of the highest priority level. An in-service register is provided for storing the identification of any request line that is being serviced by the microprocessor. In one embodiment, a set of signal lines are coupled between the in-service register and external terminals of the integrated circuit on which the interrupt controller is fabricated. A power management unit may be coupled to the external pins of the integrated circuit and thereby receives real-time information regarding an interrupt request that is currently being serviced and regarding interrupt service routines that have completed. Using this information, the power management unit advantageously stops unused clock signals and/or removes power from inactive circuit portions when an interrupt routine completes without having to estimate the time of completion. By accurately stopping unused clock signals and removing power, a reduction in the overall power consumption of the computer system can be attained.

1. Field of the Invention
This invention relates to computer systems and more particularly to interrupt controllers and power management within computer systems.
2. Background of the Relevant Art
An on-going developmental goal of manufacturers has been to reduce the power consumption of computer systems. Reducing power consumption typically reduces heat generation of the system, thereby increasing reliability and decreasing cost. In addition, power reduction has been particularly important in maximizing the operating life of battery-powered portable computer systems.
Various techniques have been devised for reducing the power consumption of computer systems. These techniques include increasing the integration of circuitry and incorporation of improved circuitry and power management units (PMU's). One specific power reduction technique involves the capability of stopping (or reducing the frequency of) clock signals that drive inactive circuit portions. A system employing such a technique typically includes a power management unit that detects or predicts inactive circuit portions and accordingly stops the clock signals associated with the inactive circuit portions. By turning off "unused" clock signals that drive inactive circuit portions, overall power consumption of the system is decreased. A similar technique involves removing the power supplied to inactive circuit portions.
The power management techniques of stopping unused clock signals and/or removing power from inactive circuit portions as described above are frequently employed within interrupt driven systems. In an interrupt driven system, peripheral and I/O devices such as keyboards, displays, timers, sensors and other components execute certain tasks independently of the central source or microprocessor, but require communication with the microprocessor at irregular, random and therefore asynchronous intervals. In such systems, a particular peripheral or I/O device generates an interrupt signal which is passed on to the microprocessor via a dedicated interrupt line or channel to request that the microprocessor interrupt its processing and communicate with the particular peripheral or I/O device. Upon detecting an active interrupt request, the microprocessor transfers control to service the particular request.
A microprocessor typically services many peripheral devices over a single input-output channel which can only be utilized by one peripheral at a time. Consequently, a priority is assigned to the various peripheral devices to discriminate between concurrent interrupt requests to service the most urgent before the others. Conventional systems have dealt with the problem of multiple interrupt sources by providing an interface circuit between the microprocessor and the peripherals to centrally sort, prioritize and control the interrupt sequencing. One such circuit is the 8259A series programmable interrupt controller manufactured by Advanced Micro Devices, Inc. and described in the publication "MOS Microprocessors and Peripherals"; pp. 3-371 through 3-388 (Advanced Micro Devices, Inc. 1987). This publication is incorporated herein by reference in its entirety.
Most interrupt controllers handle interrupt requests from eight or more peripherals or I/O devices. Each interrupt source is provided an interrupt service routine at a specified vectoral address for servicing the interrupt request. Each interrupt source has its own interrupt request line, and programmable controllers such as the 8259A allow for identification and prioritization of the various sources upon system initialization. In typical operation, the interrupt controller recognizes interrupt requests and passes the highest priority request to the microprocessor, while holding lower priority requests until the processor has completed servicing the interrupt in progress.
When a power management unit within an interrupt driven system including an interrupt controller has stopped the clock signals associated with, for example, the microprocessor, the memory subsystems, and/or other inactive peripherals, the power management unit typically monitors the interrupt request lines. If an interrupt request signal is detected, the power management unit re-starts the clock signals of the microprocessor and other peripheral components to thereby allow execution of the interrupt service routine. Since the power management unit is typically unaware of when a particular interrupt service routine has completed in such systems, the power management unit is programmed to re-stop the clock signals after an estimated period of time has elapsed. To ensure that the interrupt service routine has ample time to complete before the clock is re-stopped, the power management unit usually keeps the associated clock signals on substantially beyond the time at which the interrupt routine actually completes. In such a system, however, power is wasted when the clock signal is driven beyond the actual time of servicing the interrupt. A similar consideration applies to a situation in which the power management unit has removed power from a particular circuit portion.

Interrupt controller with external in-service indication for power management within a computer system


The invention relates to an assembly for illuminating objects with light of different wavelengths in microscopes, automatic microscopes and devices for fluorescent microscopy applications. Said assembly comprises LED light sources for illuminating the objects, which are positioned in the illumination beam path of the microscope or device. A receiving element (6; 13) that can be rotated about a rotational axis (5) is provided with respective fixing elements (7) for at least one LED (3; 3.1). The receiving device (6; 13) is situated in a housing (1) that can be placed on or positioned in the device housing (18). A drive unit (9) for the defined adjustment of the receiving device (6; 13) is provided in such a way that the LED (3; 3.1) can be positioned in front of a light emission opening of the housing (1) with the respective focal point wavelength that is required for measuring and/or observation purposes.

In wide-field fluorescent microscopy, halogen or arc lamps are generally used as sources of white light in combination with spectral filters in order to bring electromagnetic radiation of suitable wavelengths for observation or measurement onto an object to be examined or onto a specimen to be examined. However, such sources of white light have a brief service life, so that the light source must frequently be changed. These light sources are also characterized by the development of a good deal of heat, which can have unfavorable effects on the observations and measurements. Furthermore, the spectral portions in the light sources that are not used must to a great extent be suppressed in some manner. An additional disadvantage of these light sources is that it is not possible to turn them on and off rapidly, because the light sources tend to have an afterglow.
Light sources with a light output of greater than 100 mW, which is adequate for wide-field fluorescent microscopy, are known and available. These are primarily color LEDs with a spectral half-width value of approximately 20 to 50 nm. However, there are also white light LEDs that have spectral maximums in the blue and green range of the spectrum. The outputs of color LEDs are comparable to the light output that a halogen or arc lamp has after spectral filtering to approximately 20 to 60 nm bandwidth of the excitation light.
For visual illumination purposes in microscopy, it is the state-of-the-art to overlay three or more LEDs on different wavelengths (RGB light sources) in order to obtain white light, e.g. for projection purposes.
DE 100 17 823 A1 describes a microscopic illumination apparatus with a light source embodied as a light diode arrangement. This diode arrangement can comprise white light diodes or even infrared light diodes and can be embodied such that different types of illumination, such as incident illumination, transmitted light illumination, or combined illumination of the objects to be examined can be realized. It is also possible to attain "oblique" illumination of the object.
The disadvantage of this illumination device is that there is no provision for turning on and placing different LEDs in the illumination ray path of the microscope.

Assembly for illuminating objects with light of different wavelengths


A writing utensil sterilization apparatus includes a housing comprising an inlet for receiving a writing utensil and an outlet for dispensing the writing utensil, a UV light source disposed within the housing for emitting UV light, and a path disposed within the housing for guiding the writing utensil from the inlet to the outlet while exposing the writing utensil to the UV light.

Public locations experiencing a large volume of human traffic can heighten the risk of individuals contracting disease via contact with common surfaces and items that numerous individuals have handled or touched. There is a recognized need for reducing the risk of transmitting disease from one person to another in such environments.


A nonaqueous electrolyte secondary battery 10 according to an embodiment of the invention includes a positive electrode 11, a negative electrode 12, a separator 13 and a nonaqueous electrolyte liquid in which not only the positive electrode 11 contains a positive electrode active material charged at or higher than 4.3 V based on lithium and a halogenated cyclic carbonate is added in the nonaqueous electrolyte liquid, but also an inorganic insulating material particle layer is formed on the surface of at least either of the positive electrode 11, the negative electrode 12 and the separator 13. By employing such a constitution in the present invention, a nonaqueous electrolyte secondary battery using a positive electrode charged at a high electric potential of 4.3 V or more based on lithium in which the amount of a generated gas is small even when the battery is overcharged at higher temperatures, and the impact safety and reliability thereof are high, can be provided.

1. Technical Field
The present invention relates to a nonaqueous electrolyte secondary battery. Particularly, the present invention relates to a nonaqueous electrolyte secondary battery using a positive electrode charged at a high electric potential higher than 4.3 V based on lithium in which the amount of a generated gas is small even when the battery is continuously charged at higher temperatures, and the impact safety and reliability thereof are high.
2. Related Art
With the rapid spread of portable electronic equipment, the specifications required of the batteries used in such equipment have become more stringent every year, and there is particular demand for batteries that are compact and thin, have high capacity and superior cycling characteristics, and give stable performance. In the field of secondary batteries, attention is focusing on lithium nonaqueous electrolyte secondary batteries, which have high energy density compared with other batteries. These lithium nonaqueous electrolyte secondary batteries are winning an increasingly large share of the secondary battery market.
FIG. 1 is a perspective view showing a related-art cylindrical nonaqueous electrolyte secondary battery by sectioning the battery perpendicularly. This nonaqueous electrolyte secondary battery 10 uses a wound electrode body 14 produced by winding a positive electrode 11, a separator 13 and a negative electrode 12 which are laminated in this order, and is constituted by a method including: disposing insulating plates 15 and 16 respectively on the top side and bottom side of the wound electrode body 14 to prepare a parts set; holding the parts set in the inside of a steel-made cylindrical battery outer packaging can 17 serving also as a negative electrode terminal; welding not only a power collecting tab 12a of the negative electrode 12 to an inside bottom of the battery outer packaging can 17, but also a power collecting tab 11a of the positive electrode 11 to a bottom plate of a current-intercepting opening-sealing body 18 with a built-in safety device; pouring a predetermined nonaqueous electrolyte through an opening of the battery outer packaging can 17; and sealing the battery outer packaging can 17 with the current-intercepting opening-sealing body 18. Such a nonaqueous electrolyte secondary battery has such an excellent effect that battery performance and reliability are high. Further, the current-intercepting opening-sealing body 18 is a part cutting an electric connection between the coil-shaped electrode body 14 and an outside of the battery according to the pressure elevation inside the battery and the battery has such a constitution that once the electric connection has been cut, the electric connection cannot be recovered even when an internal pressure is lowered.
As a negative electrode active material used in the nonaqueous electrolyte secondary battery, carbonaceous materials such as graphite and an amorphous carbon are widely used, since carbonaceous materials have such excellent properties as high safety because dendrites do not grow therein, while having a discharge potential comparable to that of lithium metal or lithium alloy; excellent initial efficiency; advantageous potential flatness; and high density.
Further, as a nonaqueous solvent of a nonaqueous electrolyte liquid, carbonates, lactones, ethers and esters are used individually or in combination of two or more thereof. Among them, particularly carbonates having a large dielectric constant and having a large ion conductivity, thus the nonaqueous electrolyte liquid thereof are frequently used.
On the other hand, as a positive electrode active material, a lithium-transition metal compound oxide such as lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium manganese oxide (LiMnO2), spinel-type lithium manganese oxide (LiMn2O4) and lithium iron oxide (LiFeO2) is used. It is known that by using such a positive electrode in combination with a negative electrode consisting of a carbon material, a 4V-class nonaqueous secondary battery having a high energy density can be obtained. Among them, particularly because of various battery properties more excellent than those of other materials, lithium cobalt oxide and different metal elements-added lithium cobalt oxide are frequently used. However, since not only is cobalt expensive, but also the existing amount of cobalt as a resource is small, for continued use of lithium cobalt oxide as a positive electrode active material of the nonaqueous electrolyte secondary battery, it is desired to make the nonaqueous electrolyte secondary battery having even higher performance and longer life.
For making a nonaqueous electrolyte secondary battery in which lithium cobalt oxide is used as a positive electrode active material, having even higher performance and longer life, it is an essential task to enlarge the capacity and energy density of the battery and improve the safety of the battery. Among them, as a method for enlarging the capacity of the battery, enlarging the density of an electrode material, making a power collector and a separator to be a thin film and enlarging the charging voltage of the battery voltage, are generally known. Among them, enlarging the charging voltage of the battery voltage is a useful technology as a method capable of enlarging capacity without changing the constitution of the battery and is an essential technology for enlarging the capacity and energy density.
In a nonaqueous electrolyte secondary battery using a lithium-containing transition metal oxide such as lithium cobalt oxide as a positive electrode active material and using a carbon material such as graphite as a negative electrode active material, the charging voltage is generally 4.1 to 4.2 V (the electric potential of the positive electrode is 4.2 to 4.3 V based on lithium). Under such a charging condition, only 50 to 60% of the theoretical capacity of the positive electrode active material is utilized in. Therefore, when the charging voltage can be enlarged more, 70% of the theoretical capacity of the positive electrode can be utilized, thereby enabling capacity and energy density of the battery to be enlarged.
For example, JP-A-2005-85635 discloses an invention of a nonaqueous electrolyte secondary battery using a positive electrode active material in which a zirconium-containing compound is attached to the surface of lithium cobalt oxide particles, and capable of achieving advantageous charging/discharging cycle property even when the battery is charged at a high voltage of 4.3 to 4.4 V based on lithium.
Further, JP-A-2005-317499 discloses an invention of a nonaqueous electrolyte secondary battery using a mixture of lithium cobalt oxide and a layer-shaped lithium nickel cobalt manganese oxide to which different metal elements are added as a positive electrode active material, and capable of being stably charged at a high charging voltage. This positive electrode active material is produced so that by adding different metal elements of at least Zr and Mg to lithium cobalt oxide, the structural stability thereof at a high voltage is improved and further, by incorporating a layer-shaped lithium nickel cobalt manganese oxide having high thermal stability at a high voltage, the safety is secured. By using a combination of a positive electrode using the above positive electrode active material and a negative electrode having a negative electrode active material consisting of a carbon material, a nonaqueous electrolyte secondary battery capable of achieving advantageous cycle property and thermal stability even when the charging voltage is a high voltage of 4.3 V or more, has been obtained.
However, when the state of charge of the positive electrode active material is enhanced by further enhancing the charging potential of the nonaqueous battery, the decomposition of an electrolyte on the surface of the positive electrode active material and a structural deterioration of the positive electrode active material itself tend to occur. Such a structural deterioration of the positive electrode active material and decomposition of the electrolyte increase according to the increase of the charging voltage, which leads to the lowering of thermal stability, so that for providing a nonaqueous electrolyte secondary battery which has a large capacity and is capable of maintaining safety compared to that of a conventional battery having a charging voltage of around 4.2 V, there is much room for improvement.
On the other hand, as a technology for enhancing the safety of the nonaqueous electrolyte secondary battery, technologies shown in JP-A-7-220759, JP-A-2006-310010, JP-T-2001-501355 and JP-A-2005-038722 are also known. Specifically, in JP-A-7-220759, there is shown an example in which for the purpose of preventing the short circuit due to an active material which has been eliminated during the production of the nonaqueous electrolyte secondary battery, a porous protecting film having a thickness of 0.1 to 200 μm and consisting of insulating fine particles such as alumina, silica, polyethylene and the like, and a resin binder is formed on the surface of a negative electrode active material-applied layer or a positive electrode active material-applied layer.
In JP-A-2006-310010, there is shown an example in which for achieving a stabilized cycle life, in a nonaqueous electrolyte secondary battery in which a negative electrode has a width/length larger than that of a positive electrode, for the purpose of preventing the short circuit due to dendrites of lithium caused on a terminal face of the negative electrode while repeating the charging and discharging, a porous protecting film consisting of an inorganic oxide filler and a binder is formed on the surface of the positive electrode and/or negative electrode.
In JP-T-2001-501355, there is shown an example in which in an alkali metal ion secondary battery, for the purpose of preventing the short circuit due to the formation of dendritic crystals (dendrites) during the charging, fluoroethylene carbonate and propylene carbonate are incorporated in the nonaqueous electrolyte.
Further, in JP-A-2005-038722, there is shown an example using a nonaqueous electrolyte liquid in which a fluorinated cyclic ester such as fluoroethylene carbonate is added into a nonaqueous electrolyte containing a cyclic carbonate and γ-butylolactone. In the invention disclosed in JP-A-2005-038722, on the surface of the negative electrode, a stabilized film of a fluorinated cyclic ester is formed and by this film, the decomposition of the electrolyte is suppressed, so that not only the cycle property of the battery can be improved, but also the generation of a gas during the storage of the battery at higher temperatures can be suppressed. However, it is described that during an overcharging of the battery, the fluorinated cyclic ester is decomposed and a gas is generated, so that a safety valve can be quickly operated.
As already described above, the nonaqueous electrolyte secondary batteries disclosed in JP-A-7-220759 and JP-A-2006-310010 can suppress the short circuit between the electrodes due to the formation of dendrites during the charging. However, there is no description indicating suppressing the generation of a gas caused by the decomposition of the electrolyte liquid.
The nonaqueous electrolyte secondary battery disclosed in JP-T-2001-501355 can at least suppress the short circuit between the electrodes due to the formation of dendrites during the charging. However, since fluoroethylene carbonate is likely to be reduced, it has the disadvantage that the negative electrode decomposes, thereby generating carbonic acid gas and an organic gas.
Also in the nonaqueous electrolyte secondary battery disclosed in JP-A-2005-038722, since during an overcharging, by making positive use of the decomposition of an added fluorinated cyclic ester such as fluoroethylene carbonate, a safety valve is caused to be quickly operated, a large amount of gas is generated inside the battery. Such generation of a large amount of gas causes a battery swell in a prismatic battery and of an action of a current blocking mechanism in a cylindrical battery, which leads to the lowering of the reliability of the nonaqueous electrolyte secondary battery in the market.
Particularly, in the case of the positive electrode in which the charging is performed at a high electric potential of 4.4 V or more based on lithium, also on the surface of the positive electrode, not only fluoroethylene carbonate, but also dimethyl carbonate (DMC) as another nonaqueous solvent component are likely to be decomposed, so that a larger amount of gas is generated. Moreover, in a nonaqueous electrolyte secondary battery using the positive electrode in which the charging is performed at a high electric potential of 4.4 V or more based on lithium, the positive electrode active material itself is poor in thermal stability, so that there is such a disadvantage that such a nonaqueous electrolyte secondary battery is poor in impact resistance.

Nonaqueous electrolyte secondary battery


An orthodontic rapid palatal expansion (RPE) device is disclosed which includes dual body members and four guide rods for increased stability and an increased range of palatal expansion. A jack screw threadably engages each body member and, upon rotation, generates an expansive force which is applied to the palate via the guide rods. A jack screw actuating head with multiple actuating apertures provides the means for rotating the jack screw, and a locking mechanism is included for the dual purposes of (1) preventing unwanted negative rotation or unwinding of the jack screw and (2) providing sensible indications of the positive rotation of the jack screw. Each guide rod is attached to a tooth by means of an attachment sleeve which allows for removal and replacement of the RPE device without removing molar bands secured to the teeth.

A frequently encountered problem in orthodontic patients is that the arch width or palate is too narrow. This may result in a deformed and/or elongated arch and crowding of the teeth, which in turn can lead to other medical and dental problems. Devices are available which are intended to overcome these problems. Such devices, known as rapid palatal expansion (RPE) devices, comprise a rigid apparatus that includes a screw mechanism which is rotatable to apply an expansive force to the patient's palate. Over time, the expansive forces delivered by RPE devices results in widening of the palate.
Utilizing known devices, palatal expansion is accomplished by periodically (once or twice daily) turning a jack screw incorporated into the expansion device structure. One shortcoming of known RPE devices is that their palatal expansion capability is limited by the length of the screw and/or the associated structure which transfers the expansive force from the screw to the palate. Furthermore, these devices tend to become structurally unstable as they reach their limits of expansion. Currently available palatal expansion devices may provide up to approximately 11 mm of expansion. Oftentimes, however, the range of palatal expansion required in treating a patient is greater than that which is available from a single device. For example, the initial treatment of a patient with a very narrow palate may require a narrow and compact expansion device. As the patient's treatment progresses and the palatal width increases, the initial expansion device becomes inadequate. As a result, the orthodontist must disconnect the device from the patient's teeth, remove it and replace it with a device having a larger palatal expansion range for continued treatment. This drawback requires the clinician and the patient to devote more chair time during the course of the orthodontic treatment, which adds to the overall expense of the process.
Another drawback associated with known palatal expansion devices is the inability to accurately determine how much rotation of the jack screw is required or has been accomplished. An additional and related drawback is that the jack screw may have a tendency to "unwind," resulting in contraction of the device, a decrease in the force applied to the patient's teeth and palate, and unwanted sagittal movement of the teeth and palate.
Therefore, a need exists for an improved rapid palatal expansion device which overcomes the drawbacks associated with existing palatal expansion devices.


A highly legible key that is durable and suitable for electronic devices, including gaming consoles and controllers. The key includes an outer layer and an inner layer and may be formed by a two-shot injection molding process. The outer layer has a cavity delineating a negative form of a desired indicia or indicium. The inner layer is located interior to the outer layer filling the negative form with the desired indicium. The outer layer is formed of transparent or translucent material and the inner layer is formed of an opaque or darker material, such that, the indicium is visible through the outer layer material. The outer layer can be tinted. The outer layer protects and magnifies the indicium of the inner layer. The inner layer in the region of the indicium can be domed for increased visibility. The outer layer can have a dome surface, which is on a slope for improved finger-to-button contact. The outer layer can have a step and a tab for retaining the button in an electronic device housing.

The present invention relates to key switches, and more particularly to a key switch having a key or pushbutton made from an outer layer and an inner layer where the inner layer bears some indicium and the outer layer protects and magnifies the indicium. The invention further relates to a game controller incorporating the inventive key or pushbutton.
A variety of electric and electronic devices use keyboards, key pads, or pushbuttons. For example, a personal computer may have a keyboard, a mobile or cellular telephone may have a key pad, a public telephone may have a key pad or series of pushbuttons, and an electronic game controller may have pushbuttons. In each of these electronic devices, keyboards, key pads, and pushbutton assemblies, a key is depressed to activate a switch.
A key generally has indicia or indicium to indicate the function of the key. The indicia or indicium (hereafter, xe2x80x9cindiciumxe2x80x9d) can be letters, numbers, symbols, words or other indication of the assigned function to the key. The indicium can be painted on a top surface of the key so that a user can determine the function of the key. The problem with painted keys is that the indicium paint can wear-off leaving the user without means to readily determine the function of the key. This problem is particularly prevalent in applications subject to highly repetitive use and/or heavy duty use. One example, of a highly repetitive use application is a public telephone in a popular area where the telephone is subject to frequent use. Public telephones can also be subject to heavy duty use, including abuse, as well as, being subject to outdoor environmental elements. In these instances, paint on the keys indicating each of the key""s numerical value can and often does wear off. An example of both high use and heavy duty use, is a game controller device where the use is highly repetitive, and the use is increasingly hard with escalating enthusiasm for the game.
To avoid the problem of the indicium paint wearing-off, manufacturers have made keys from different colored materials. In this instance, one material protrudes through a second material at the point of the indicium. The second material has through-openings delineating some indicium, and the first material fully protrudes into these through-openings. For example, FIG. 3B of U.S. Pat. No. 5,172,990 to Weng, shows a push-button 5 having a face plate 55 and bottom portion 56 where face plate 55 has holes conforming to the shape of letters or Arabic numerals 561. Weng represents that letters or numerals of this type of push-button key will not become obscured or blurred after a prolonged usage of the key (col. 3, lines 18-29). A drawback of the key of Weng is that the indicium is exposed to the surface. While the exposed indicium may not rub-off like paint, the indicium may still become fouled, particularly around a periphery of the indicium where the two materials meet. Over time the juncture between materials may enlarge due to wear and relative movement between the face plate and bottom portion creating a crevasse for contaminants. Furthermore, the exposed indicium may be difficult to discern due to the seemingly small size of the indicium.
In small electronic devices, hand-held devices, and devices that have a large number of keys arranged closely together, small size indicia are particularly problematic. U.S. Pat. No. 5,635,927 to Lin discloses an illuminated key cap having a plano-convex lens for showing a key identification pattern in an enlarged scale. A bottom wall II of the plano-convex lens is covered with a light blocking ink. This light blocking ink is laser engraved to define a non-ink pattern 12 in which light is allowed to pass. Viewed from the top, the convex wall outer surface of the key cap is said to cause the pattern 12 to be viewed in an enlarged scale (col. 3, lines 23-27). The problem is that this key cap is difficult to manufacture because the key cap is made from at least two separately produced parts. One of the parts is subject to the steps of photo-resist inking and laser engraving. That part must then be bonded together with the second part, sandwiching the remaining portions of the photo-resist layer at the interface. It appears that this mix-match of materials at the interface of the two separately produced parts could lead to separation of the parts over time. Accordingly, a key that overcomes the problems and disadvantages of the prior art is needed.
It is an aspect of the present invention to provide a highly legible key. Keys that have top quality visible characteristics are highly desirable in performance and precision applications.
It is another aspect of the present invention to provide a highly durable key. A key that maintains the functional and aesthetic qualities throughout the life of an electronic device in which the key is employed is needed.
It is yet another aspect of the present invention to provide a key that maintains legibility of the indicium and maintains its aesthetic qualities throughout highly repetitive and heavy duty use. A key that maintains its indicium and aesthetic qualities is very desirable in the console or controller gaming industry.
It is a further aspect of the present invention to simplify the manufacturing steps for making a key. Still further, it is an object to eliminate manual assembly steps for making a key and provide a key suitable for high volume production, and thus, reduce the manufacturing costs associated with making keys.
According to another aspect of the present invention, there is provided a key comprising an outer layer and an inner layer. The outer layer and the inner layer may be an outer shell and an inner core, respectively. The outer layer is formed such that an inner surface of the outer layer has a recess delineating a negative form of the desired indicium. The inner layer is formed to the interior of the outer layer and fills the negative form of the desired indicium. The outer layer is formed of transparent or translucent material such that the material of the inner layer is visible through the outer layer. In this manner, the outer layer protects the indicium from wear and from fouling. The outer layer can be tinted to improve key identification and discrimination such as by color recognition. The key can also be tinted to add to the aesthetic appearance of the key and of the electronic device in which the key is employed.
Accordingly to another aspect of the present invention, the inner layer of the key is formed of a material such that the indicium is readily discernable through the outer layer. In this manner, the material may be opaque or tinted, and the color selected for aesthetic appearance of the key, and for color complement or contrast with the outer layer and surrounding electronic device casing.
According to another aspect of the present invention, the outer surface of the inner layer may be curved or domed in the region of the indicium. This curve or dome in the region of the indicium allows the key indicium to be easily viewed from the side of the key, as well as, directly overhead.
According to yet another aspect of the present invention, an outer layer with a domed exterior surface may be further desirable in that the dome can impart a level of magnification to the indicium located below the domed exterior surface.
According to still another aspect of the present invention, the outer layer has a tip portion axially aligned with a base portion. A step or a ledge can be created at the juncture of these two portions that is useful for retaining the key within an opening in an electronic device casing. The tip portion may be elliptical or oval shaped and the base portion may be cylindrically shaped.
According to another aspect of the present invention, the dome exterior surface of the outer layer is positioned along a sloping line. Positioning the dome along a slope improves finger-to-button contact by creating a larger dome surface area ensuring that a user engages the key when the user""s fingers are moving generally horizontally across a surface of an electronic device casing.
According to still another aspect of the present invention, the key may be formed from the same type of polymer though of different colors or transparencies. The key may be formed by a two-shot molding sequence where a first mold is provided to form the outer layer and then a second mold is provided to form the inner layer. The outer layer is used to form an outer part of the second mold.
Further, the key may include a tab for retaining the key in an electronic device casing. The tab and the step or ledge are for engaging a structure of an electronic device casing, such that, the key can not misalign and dislodge from the electronic device.
According to another aspect of the present invention, the key includes an inner layer having a web. The web can be used for depressing a flexible contact switching assembly. The web may be recessed in the outer layer for centering the contact switching assembly with the key.
Other aspects and features of the invention will be more fully understood from the following detailed description and appended claims when taken with the accompanying drawings.

Multi-layer keys with translucent outer layer


Vitamin E TPGS/drug compositions and methods are provided which obviate the need for surfactants or non-evaporated co-solvents because the active drug component is dissolved directly into Vitamin E TPGS to form a true molecular solution--not an emulsion or a micro-emulsion. The invention provides a slowly dissolving TPGS/Drug matrix that absorbs gastrointestinal fluid into the matrix at the dosage form/fluid interface, where a gel-like liquid crystal is formed. This gel front forms a liquid crystal boundary where drug dissolution is highest. At this liquid crystal/GI fluid boundary, a synchronization takes place in which the rate of formation of liquid crystals equals the dissolution rate of liquid crystals at the water interface, thereby giving controlled order release of the drug into the GI tract. The rate of dissolution is also controlled by the geometry of the dosage form. The solid Vitamin E TPGS/drug matrices of the invention can be solidified and compressed into tablets or filled into capsules, with other excipients, binders and/or fillers. The solid TPGS/drug solution of the invention also can be made into an immediate release liquid formulation upon addition of water, or into a controlled release system solid tablet by the use of impermeable or semi-permeable barriers or coatings surrounding portions of the tablet.

A. Technical Background.
1. Drugs.
A drug is broadly defined as a chemical agent or medicinal substance that therapeutically affects the living processes of a patient. To perform its characteristic therapeutic activity, a therapeutic amount of a drug compound must be made bioavailable, i.e., it must be able to get to its site of action in the patient, via the blood stream, in the case of an oral or parenteral drug formulation. With respect to oral drug formulations (e.g., tablets, caplets, and capsules), a therapeutic amount of the drug must be first released from the dosage form over a given time in the gut, and, must be solubilized and absorbed in the gastrointestinal tract. After absorption, the active drug compound is metabolized, passes through the liver, and then it (and/or one or more of its metabolites) enters the general circulatory system towards the site of action. Thus, proper drug release from the dosage form, and solubilization of the active drug compound in the GI tract, are the critical first steps in the development of oral drug therapies.
The present invention relates to drug delivery systems that utilize liquid crystal structures and other means to dissolve and control the rate of dissolution of drug compounds, e.g., cyclosporine and nifedipine, that are poorly soluble in the gastrointestinal tract.
Medicinal substances which can be used in the present invention are varied and include, but are not limited to, antitussives, antihistamines, decongestants, alkaloids, mineral supplements, laxatives, vitamins, antacids, ion exchange resins, anti-cholesterolemics, anti-lipid agents, antiarrhythmics, antipyretics, analgesics, appetite suppressants, expectorants, anti-anxiety agents, anti-ulcer agents, anti-inflammatory substances, coronary dilators, cerebral dilators, peripheral vasodilators, anti-infectives, psycho-tropics, antimanics, stimulants, gastrointestinal agents, sedatives, antidiarrheal preparations, anti-anginal drugs, vasodilators, anti-hypertensive drugs, vasoconstrictors, migraine treatments, antibiotics, tranquilizers, anti-psychotics, antitumor drugs, anticoagulants, antithrombotic drugs, hypnotics, anti-emetics, anti-nauseants, anti-convulsants, neuromuscular drugs, hyper- and hypoglycemic agents, thyroid and antithyroid preparations, diuretics, antispasmodics, uterine relaxants, mineral and nutritional additives, anti-obesity drugs, anabolic drugs, erythropoietic drugs, anti-asthmatics, cough suppressants, mucolytics, anti-uricemic drugs and mixtures thereof. Popular H.sub.2 -antagonists which are contemplated for use in the present invention include cimetidine, ranitidine hydrochloride, famotidine, nizatidine, ebrotidine, mifentdine, roxatidine, pisatidine and aceroxatidine. Analgesics include aspirin, acetaminophen, and acetaminophen plus caffeine, Ibuprofen. Other preferred active drugs for use in this invention include anti-diarrheals such as immodium AD. Also contemplated for use herein are anxiolytics such as Xanax; antipsychotics such as clozaril and Haldol; non-steroidal anti-inflammatories (NSAIDs) such as Voltaren and Lodine; anti-histamines such as terfenadine, Hismanal, Relafen, and Tavist; antiemtics such as Kytril and Cesamet; bronchodilators such as Bentolin, Proventil; antidepressants such as Prozac, Zoloft, Paxil and Buspar; antimigraines such as Imigran, ACE-inhibitors such as Vasotec, Capoten and Zestril; Anti-Alzheimers agents, such as Nicergoline; and Ca.sup.H -Antagonists such as Procardia, Adalat, and Calan, and salts thereof.
Especially preferred drugs for use in this invention are the immunosuppressants, e.g., the cyclosporins, and calcium antagonists, e.g., nifedipine and Ditiazem HCL. As discussed below, the present invention can be used for both hydrophilic and lipophilic drugs.
2. Cyclosporine, Nifedipine and Diltiazem.HCl.
The cyclosporins comprise class of structurally distinctive, cyclic, poly-N-methylated endecapeptides, possessing pharmacological activity, including, immunosuppressive, anti-inflammatory and/or anti-parasitic activity. Cyclosporine, also known as Cyclosporin A (see chemical structure shown below), was one of the first Cyclosporins to be isolated. See U.S. Pat. No. 5,342,625 to Birgit et al. Cyclosporine is a cyclic polypeptide immunosuppressant agent consisting of 11 amino acids, and is produced in nature as a metabolite by the fungus species Beauveria nivea. See PHYSICIAN'S DESK REFERENCE, 51.sup.st Ed. (1997), p. 2405.
The chemical structure of cyclosporine is: ##STR1##
The present invention is intended to cover compositions of and methods employing the use of the cyclosporin class, which can be described as a group of nonpolar cyclic oligopeptides with immunosuppresant activity. This include Cyclosporins A, B, C, D and G. Cyclosporins are practically water-insoluble substances formed from neutral, hydrophobic amino acids. As a consequence of their high molecular weight (over 1000), poor water solubility, the cyclosporins are absorbed only to an insignificant extent from the gastrointestinal tract when administered orally. See U.S. Pat. No. 5,430,017 to Antalne et al. After oral administration, the bioavailability of cyclosporine or cyclosporin A is markedly poor and variable due to factors that include its poor solubility in aqueous gastrointestinal fluids, its high lipophilicity, as well as other factors such as impaired bile flow and fat content in the diet. See Chang et al., Clinical Pharmacology & Therapeutics, Vol. 59, No. 3 (March 1996).
Cyclosporine dosing is variable and depends on the type of organ transplanted. Generally, it about 7, 8 and 9 mg/kg of body weight, divided into two doses, for the heart, liver, renal (kidney), respectively. Cyclosporine has a biphasic terminal half-life of about 8.4 hours. Cyclosporine forms a solid solution with Vitamin E TPGS.
Nifedipine, or 3,5-pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-4-(2-nitrophenyl)-, dimethyl ester (see chemical structure shown below), is a potent peripheral vasodilator. About 90% of an oral dose of nifedipine is absorbed, but its bioavailability is 65% to 70%, and there is significant first pass metabolism. Greater than 10% of the drug is bound to plasma protein, and is metabolized to inactive metabolites, probably by the liver. Most of the inactive metabolites are excreted. The half-life is two to six hours.
The chemical structure of nifedipine is: ##STR2##
Nifedipine is practically insoluble in water. Its current dosage forms include 10 and 20 mg capsules. It is dosed three to four times a day, and doses exceeding 180 mg a day are not recommended. Nifedipine side effects of overdosing include pronounced hypotension requiring cardiovascular support.
For these reasons, Nifedipine is a good candidate for both enhanced solubility systems, and/or for use in a controlled release device which can effectively deliver a one to two per day dose. Nifedipine forms a solid solution with Vitamin E TPGS.
Diltiazem Hydrochloride, or benzothiazepin-4(5H)-one, 3-(acetyloxy)-52-(dimethylamino)ethyl!-2,3dihydro-2(4-methoxyphenyl)-, (+)-cis-, monohydrochloride (see chemical structure below), is a potent coronary vasodilator. Diltiazem-HCl is freely soluble in water. It is 80% absorbed orally, but only 40 to 60% of an oral dose reaches the systemic circulation because of first-pass metabolism.
The chemical structure of diltiazem hydrochloride is: ##STR3##
Diltiazem.HCl is metabolized extensively to several metabolites, some of which have weak coronary vasodilator activity. Less than 4% of the drug appears unchanged in the urine, and plasma half-life is about 4 hours. Diltiazem may reach saturation kinetics after single doses of greater than 60 mg. For these reasons, it is desirable to provide a one to two per day controlled release form of diltiazem hydrochloride. Diltiazem side effects include hypotension, itching, burning, flushing, arrythmia, and atrail flutter. Diltiazem forms a solid dispersion with Vitamin E TPGS.
3. Drug Formulations.
Once pharmacologic activity for a drug compound becomes known, the next objectives are to design drug product systems and/or devices that will effectively and efficiently deliver the compound to its active site. Moreover, after a system is developed and used, skilled drug formulators will often seek to improve or completely re-design it with the goal of optimizing drug delivery.
Broadly speaking, drug delivery systems include those that deliver the active drug compound by topical, aerosol, oral, injectable or rectal means. The oral dosage forms include tablets, capsules, gel capsules, syrups, suspensions, emulsions, micro-emulsions, pre-emulsion concentrates, and similar systems.
The development of an oral dosage form for an active drug is often driven by solubility concerns. The drug formulation, i.e., the combining of the active drug compound together with other inactive compounds and ingredients, will affect the amount or concentration of the drug compound that gets to the active site over the course of a given time period. The composition of the drug formulation directly affects the solubilization of the drug compound in the gastrointestinal tract, and consequently the extent and rate of the absorption of the active drug compound into the blood stream. In addition, the therapeutic value of a drug is also affected by the rate in which the drug dose is released from the delivery system itself, which in turn affects the rate and extent of solubilization of the active compound in the gastrointestinal tract prior to absorption.
The formulation of an acceptable dosage form for the delivery of a drug compound to the active site in the human body is a complex process involving trial and error. The development of an oral formulation for an insoluble or poorly soluble drug often involves the designing of a system that will affect the pH of the micro-environment surrounding the drug form in the gastrointestinal tract after ingestion.
In particular, the formulation may contain disintegrants and/or other agents that work to increase or decrease the pH of the micro- environment, and thus enhance drug dissolution. In addition, the drug may also be granulated to reduce its particle size and/or increase the surface area that is exposed to the gastric fluid. The amount of exposed surface area will affect the rate of drug dissolution and thus the amount of active drug that will be absorbed by the patient.
With respect to drug compounds of very poor or limited solubility, like cyclosporine, skilled formulators have used co-solvents, surfactants or wetting agents to reduce the surface tension of the liquid environment of the gastric fluid in which the active drug is to be dissolved. These agents wet the active drug more quickly so that more of the drug is exposed to the gastric fluid in a shorter time, and may enhance its dissolution. Common types of surfactants and co-solvents that can be used include the cationic, anionic (e.g., sodium lauryl sulfate and gelatin), and nonionic (e.g., MYRG) types, as well as such co-solvents as the polyethylene glycols ("PEGs").
The role of the binder in the tablet drug form is to provide a tablet with sufficient hardness and integrity, but also must allow for sufficient disintegration and dissolution in the gastric environment. In this sense, a binder performs the opposite function of a disintegrant. The types of binders that can be used in drug formulations include gelatins of numerous grades, starches and starch derivatives (including corn starch, StaRx 1500, carboxymethylated starch), cellulose derivatives, polyvinylpyrollidones, Veegums, polyethylene glycols, sugars, e.g., sucrose and lactose, sodium alginate and waxes.
The fillers used to bulk up a drug tablet or other form also should not interfere with the tablet's dissolution. Numerous fillers include the starch derivatives, sugars (e.g., lactose and sucrose), sorbitol, mannitol, cellulose derivatives and their inorganic salts, corn starch, Starch 1500, calcium phosphate, and Avicel.
Likewise, lubricants aid in the machining of a drug tablet. Every tablet needs a lubricant so that it will be ejected from the machine die with minimum force. However, the lubricant also must not interfere with the dissolution of the tablet. Lubricants include waxes, fatty acids, sodium salts of fatty acids and stearates.
4. Controlled Release Drug Formulations.
Controlled release formulations employ means that allow less drug to be released into the gut over time, and thereby allow the body to see lower concentrations of drug per unit time. They can thereby provide continuous delivery of the drug for a predetermined period, with predictable and reproducible kinetics. The term "controlled release" also refers to systems that provide control over the movement of the dosage form through the gastrointestinal tract, or that deliver the drug to a specific area for either local or systemic effect. See, generally, Gupta and Robinson, TREATISE ON ORAL CONTROLLED-DRUG DELIVERY Text Ed. 1992!, Ch. 6, edited by Agis Kydonieus, Mancel Dekker, Inc. ISBN 0-8247-8519-3.
Generally, there are three categories of oral drug delivery systems: conventional or immediate, first order slow release, and zero order release. In the conventional dosage form, a large maximum/minimum plasma drug concentration (Cmax/Cmin) is typically observed due to a rapid absorption of the drug into the body, relative to the drug's therapeutic index, i.e., the ratio of the maximum drug concentration needed to produce and maintain a desirable pharmacological response. In the conventional systems, drug content is released into the gastrointestinal tract within a short period of time, and plasma drug levels peak at a given time, usually within a few hours after dosing. The design of conventional oral drug delivery systems, including the cyclosporine formulations of the prior art, is generally based on getting the fastest possible rate of drug dissolution, often at the risk of creating undesirable, dose related side effects.
The goal of a controlled release formulation is to improve the therapeutic value of the active drug component by reducing the ratio of the maximum and minimum plasma drug combination (Cmax/Cmin) while maintaining drug plasma levels within the therapeutic window. The controlled release form seeks to give a drug with sufficient frequency and dose so that the ratio Cmax/Cmin in plasma at steady state is less than the therapeutic index, and to maintain drug levels at constant effective concentrations. In principle, in order to keep a constant plasma drug level, the drug formulation should be designed to provide an input rate into the body that is or approaches zero order, although in vivo profiles rarely match zero order kinetics based on in vitro models. The dosage forms of the present invention can be constructed along zero order, first order, or conventional release systems.
The type of controlled release systems that involve continuous or controlled release of the active drug employ dissolution control, diffusion control, a combination of dissolution and diffusion control, ion-exchange resins, osmotically controlled devices, slow dissolving salts or complexes, and pH independent formulations. These systems include tablet or similar formulations impregnated with water insoluble waxes, such as fatty acids, carnuba wax, and bees wax, or polymers, such as polyethylene, polypropylene, methacrylates, silicones, and PVC. When gastric fluid penetrates the surface of a polymer-impregnated tablet, the drug dissolves and diffuses through the polymer network. Other systems in these categories employ the encapsulation or microencapsulation of the drug particles with a slowly dissolving material prior to tablet compression. See Gupta and Robinson, supra; EUDRAGIT brochure: "EUDRAGIT Powders for Direct Compression," Huls America Inc, Somerset, N.J.; and UNION CARBIDE brochure: "SENTRY POLYOX, Water-Soluble Resins, NF In Sustained-Release Oral Pharmaceutical Applications," Union Carbide, Danbury Conn. (1995).
Other controlled release formulations are comprised of hydrophillic systems wherein a preparation of hydrophilic polymers, such as hydroxy propyl methyl cellulose, methyl cellulose, sodium carboxy methyl cellulose, polyethylene oxide polymers, natural gums and starches, is dispersed together with the drug and other excipients. These hydrophillic systems work by the uptake of the gastric fluid by the polymer, which is followed by swelling, dissolution of the drug, and diffusion through the swollen complex. Alternatively, they may work by the swelling of the complex and then erosion or dissolution of the polymer complex. See Gupta and Robinson, supra.
Generally, controlled delivery of lipophilic drugs requires techniques different than those employed with hydrophilic drugs. Lipophilic drugs must be solubilized and are, preferably, released in a controlled fashion, whereas hydrophilic drugs tend naturally to increase the rate at which water absorption and drug diffusion occurs. Consequently, a hydrophilic drug form must be modified to slow down the delivery.
The present invention, however, does not depend on the lipophilicity or hydrophilicity of the drug component because it functions by gradual surface dissolution of liquid crystal structures. As discussed below, the Vitamin E TPGS component of formulations within the scope of the present invention serves not only to solubilize lipophilic drugs and to disperse hydrophilic drugs, but also establishes a viscous liquid crystal gel structure at the dosage form/water interface, at which the dosage form slowly erodes as it goes into solution. See e.g. FIG. 3!. Thus, controlled diffusion of both hydrophilic and lipophilic drugs formulated in accordance with the present invention can be achieved.
In general, the advantages of controlled release systems may include reduced dosing frequency, better patient convenience and compliance, reduced gastrointestinal side effects and/or toxic side effects, fewer fluctuating plasma drug levels, more uniform drug effect, and lesser total dose.
It is particularly desirable to employ a controlled release system for cyclosporine as an alternative to the immediate release cyclosporine drug products of the prior art, e.g., NEORAL and SANDIMMUNE. The prior art cyclosporine products can result in toxic side effects, including nephrotoxic effects, due to the rapid release and absorption of high blood concentrations of the drug. See PHYSICIAN'S DESK REFERENCE, 51.sup.st Ed. (1997), p. 2405 (black box warning). Nephrotoxicity is believed to be a serious side effect caused by cyclosporine, and is dose related. When the dose is reduced, or another immunosuppressive agent is substituted, renal function improves. See e.g., Valantine H A, Shroeder I S, N. Engl. J. Med. 1995; 333: 660-661.
In an effort to reduce the nephrotoxic risks associated with cyclosporine therapy, prior art investigators have co-administered the drug with an agent that delays the metabolism of cyclosporine, effectively extending the half life and reducing the dose required to maintain therapeutic blood levels. However, this invention seeks to achieve these goals by providing a novel controlled release drug delivery system that does not require the co-administration of other agents. The present invention can control and reduce the release of cyclosporine per unit time, making it less than that of the immediate release formulation of the prior art. Thus, the present invention, unlike the prior art, does not overload the kidneys with immediate high levels of cyclosporine, thereby reducing the risks of nephrotoxicity.
5. Vitamin E TPGS.
In recent years, Vitamin E TPGS, or d-.alpha.-tocopheryl polyethylene glycol 1000 succinate, has been used as one of many excipients in complex immediate release drug formulations, usually emulsions or micro-emulsions, wherein the active drug compound is poorly soluble in water.
Vitamin E TPGS is a water soluble derivative of natural source Vitamin E, and has a dual nature, similar to an amphiphile, of hydrophilicity and lipophilicity. TPGS is also believed to be a bioavailability enhancer when co-administered with some lipophilic drugs, including cyclosporine.
The structure of the principal component of TPGS is: ##STR4##
Vitamin E TPGS is miscible in water and forms solutions with water at concentrations up to approximately 20% wt, beyond which liquid crystalline phases may form. It has a melting point of about 38.degree. to 41.degree. C. (100.degree. to 106.degree. F.). See, generally, "Eastman Vitamin E TPGS" Eastman Brochure, Eastman Chemical Co., Kingsport, Tenn. (October 1996). It has a relatively high crystallinity, high degradation temperature, and good thermal stability.
TPGS forms liquid crystalline phases in water. Micelles are formed at 0.02 percent weight. When TPGS concentration is above 20 percent weight, higher-viscosity liquid crystalline phases start to form. With increasing TPGS concentration in water, more complex liquid crystalline phases evolve, e.g., from isotropic globular micellar, to isotropic cylindrical micellar and hexagonal, hexagonal, mixed hexagonal and reversed hexagonal, reversed globular micellar, and to the lamellar phase. See "Eastman Vitamin E TPGS" Eastman Brochure, Eastman Chemical Co., Kingsport, Tenn. (October 1996).
TPGS is known as a surface active agent or as an emulsifier for use in complex formulations that include a number of other excipients that function as solvent, binder, and filler. However, the inventor herein knows of no examples wherein TPGS is used as the only or major solvent in a drug formulation, or as the delivery vehicle for controlled release of drugs, performing all of the functions of solvent, surfactant, binder, filler, and liquid crystal gel former. The Eastman Brochure, supra, suggests the blending of TPGS with water and a lipophilic drug to form an oil in water emulsion, but does not teach or suggest the direct melt blending, or solvent evaporation, of a lipophilic drug, such as cyclosporine, or dispersion of hydrophilic drugs, e.g., Diltiazem.HCl Salt, and TPGS, to form a solid solution or dispersion of drug and TPGS. (See Hawley's Condensed Chemical Dictionary (1987) for a definition of "dispersion"). Nor does the prior art teach or suggest the dry blending or mechanical mixing and compression of a solid solution of drug and Vitamin E TPGS for tablets, capsules or powder forms of drug/TPGS formulations where the drug is in a true Vitamin E TPGS solution, or solid dispersion, as opposed to an emulsion. The prior art also fails to disclose or teach the art of controlling the release or dissolution of the active drug form through the use of TPGS liquid crystal formation. Nor does the prior art teach the controlled dissolution at the surface of an oral dosage form, using liquid crystal formation of TPGS with water as the control mechanism.

Drug delivery systems utilizing liquid crystal structures


Modified fuel cells with improved distribution of humidity and/or temperature are provided.

Fuel cells are electrochemical energy conversion devices considered as a possible alternative to internal combustion engines. Fuel cells convert a hydrogen containing fuel such as methanol or hydrogen to electrical energy by an oxidation reaction. A by-product of this reaction is water. Adequate output voltage entails the assembly of multiple fuel cells, connected in series, into fuel cell stacks.
Various proton exchange membrane (PEM) fuel cells have been described.
One type of PEM fuel cell comprises a solid polymer electrolyte (SPE) membrane, such as a sulfonated fluorinated polymer membrane material known as Nafion, which provides ion exchange between cathode and anode electrodes. Various configurations of SPE fuel cells as well as methods for their preparation have been described. See e.g. U.S. Pat. Nos. 4,469,579; 4,826,554; 5,211,984; 5,272,017; 5,316,871 5,399,184; 5,472,799; 5,474,857; and 5,702,755.
PEM fuel cells operate properly only if the membrane is sufficiently wet. A supply of water is required to retain proton conductivity of the polymer membrane and water management is essential for enhancement of cell performance (Choi et al. J. Power Source 2000 86:197-201; Fuller, T. F. and Newman, J. J. Electrochem. Soc. 1992 139:1332; Xie, G. and Okada, T. J. Electrochem. Soc. 1995 142:3057; Bernardi, D>M. J. Electrochem. Soc. 1990 137:3344; Sakai et al. J. Electrochem. Soc. 1986 133:88 and Yeo, R. S. and McBreen, J. J. Electrochem. Soc. 1979 126:1682).
Typically, hydration is maintained by humidification of the reactant streams prior to introduction into the electrochemically active regions of the fuel cell. Such systems also typically require heating of the fuel prior to its introduction into the fuel cell. A system providing both heat and humidification to the reactant stream prior to entry into the fuel cell is described in U.S. Pat. No. 4,530,886. The required humidification and heating apparatus of such systems, however, add complexity to the fuel system as components such as a humidification water pump, piping, a water reservoir and a filtration unit, in addition to the humidification module and heater, are also needed. Further, additional power is required for operating the pumps and heating the stream.
Thus, various attempts have been made to provide simpler, more energy efficient means for providing temperature control and/or humidification to fuel cells.
For example, U.S. Pat. No. 5,382,478 describes an electrochemical fuel stack with a humidification section located upstream from the electrochemically active section. The upstream location of the humidifier allows for fewer manifolds in the fuel cell, thereby maximizing space for the electrochemical reaction to occur.
U.S. Pat. No. 6,500,573 discloses a humidifier device for use with fuel cells comprising a mist humidifier unit for adding mists to process gas supplied to an electrolyte equipped in a fuel cell. This device is further equipped with a unit control device for intermittently operating the mist humidifier unit in accordance with operating condition of the fuel cell.
U.S. Pat. No. 5,958,613 discloses a polymer electrolyte fuel cell system with a polymer electrolyte fuel cell made up of a cell main body, a mixture generator for generating a gas-liquid mixture by mixing fuel gas which has been supplied from a fuel gas supply with water, and a means for supplying the gas-liquid mixture to the anode-side channels. The gas-liquid mixture permits moistening of the solid-polymer membrane without requiring a humidifier to humidify fuel gas and oxidant gas and cools the cell main body without providing a cooling channel therein.
U.S. Pat. No. 6,653,012 describes a simpler humidifier having a plurality of water-permeable hollow fiber membranes placed along the lengthwise direction of the housing of the humidifier. Gases, each having a different moisture content flow inside and outside the hollow fiber membranes to carry out moisture exchange so that dry air having low moisture content is humidified.
Humidification of fuel cells has also been provided using water transport plates. Water transport plates are porous structures filled with water. During fuel cell operation, the water transport plate supplies water locally to maintain humidification of a proton exchange membrane, removes product water formed at the cathode, removes by-product heat via a circulating coolant water stream, conducts electricity from cell to cell, provides a gas separator between adjacent cells and provides passage for conducting the reactants through the cell.
U.S. Pat. No. 4,973,530 discloses a fuel cell with a first flow field for transporting a fuel gas and a second flow field for receiving the gas which also has a water transport membrane for regulating humidity of the gas within the first flow field.
U.S. Pat. No. 5,965,288 also describes a gas-humidifying device for use with a fuel cell in which water permeable membranes are provided with fuel gas passages and oxygen-containing passages formed on one side of the water permeable membrane and humidifying water passages formed on the other side of the membrane. Medium supply passages are also provided independently from, yet in proximity to the water passages, for supplying a medium having a melting point lower than that of water so that melting of the water in the interior of the humidifier can be easily and swiftly carried out.
U.S. Pat. No. 6,197,442 discloses a water transport plate for use in improving fuel cell operations comprising graphite powder, reinforcing fibers, cellulose fibers and a thermosetting resin, the slurry of which is showered onto a screen to form a planar sheet which is dried to form paper. The paper is then cut into a desired size, laminated under heat and pressure, carbonized and graphitized to form a water transport plate.
U.S. Pat. No. 6,066,408 also describes a plate, referred to as a cooler-humidifier plate for use in a proton exchange membrane (PEM) fuel cell stack assembly. This cooler-humidifier plate combines functions of cooling and humidification with the fuel cell stack assembly, thereby providing a more compact structure, simpler manifolding, and reduced reject heat from the fuel cells. In this plate, coolant on the cooler side of the plate removes heat generated within the fuel cell assembly. On the humidifier side of the plate, evaporating water humidified reactant gas flows over a moistened wick. After exiting the humidifier side of the plate, the humidified reactant gas provides needed moisture to the proton exchange membranes used in the fuel stack assembly. Structural support is maximized in this plate by ensuring that the ribs that form the boundaries of channels on one side of the plate have ends at locations that substantially correspond to the location of ribs on the opposite side of the plate.
U.S. Pat. No. 6,632,555 discloses a proton electrolyte membrane fuel cell having a closed coolant path within the fuel cell, a humidifier with a humidification fluid flow path and a fuel and air gas supply passage continuous in, through and out the humidifier. In this system, the humidifier and the fuel and air gas supply passage are separated by a water permeable membrane impervious to organic materials, but which allows water from the humidification fluid flow path to enter the fuel and air gas supply passage.
Self-humidifying systems for fuel cells have also been described.
For example, U.S. Pat. No. 6,106,964 describes a solid polymer fuel cell system and a method for humidifying and adjusting the temperature of a reactant gas stream wherein heat generated by the fuel cell and water vapor in a reactant stream exhausted from the fuel cell are used to heat and humidify the reactant gas stream prior to introduction into the fuel cell.
U.S. Pat. No. 6,416,895 also describes a solid polymer fuel cell heated and humidified using heat generated by the fuel cell and water vapor from the fuel cell exhaust. This is achieved by flowing a reactant gas supply stream and a fuel cell exhaust gas stream on opposite sides of a water permeable membrane in a combined heat and humidity exchange apparatus.
The present invention provides modified fuel cells with internal humidification and temperature control systems.

Modified fuel cells with internal humidification and/or temperature control systems


Methods for calibrating metrology apparatuses and determining a parameter of interest are disclosed. In one arrangement, training data is provided that comprises detected representations of scattered radiation detected by each of plural metrology apparatuses. An encoder encodes each detected representation to provide an encoded representation, and a decoder generates a synthetic detected representation from the respective encoded representation. A classifier estimates from which metrology apparatus originates each encoded representation or each synthetic detected representation. The training data is used to simultaneously perform, in an adversarial relationship relative to each other, a first machine learning process involving the encoder or decoder and a second machine learning process involving the classifier.

A lithographic apparatus is a machine constructed to apply a desired pattern onto a substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A lithographic apparatus may, for example, project a pattern (also often referred to as "design layout" or "design") at a patterning device (e.g., a mask) onto a layer of radiation-sensitive material (resist) provided on a substrate (e.g., a wafer).
To project a pattern on a substrate a lithographic apparatus may use electromagnetic radiation. The wavelength of this radiation determines the minimum size of features which can be formed on the substrate. Typical wavelengths currently in use are 365 nm (i-line), 248 nm, 193 nm and 13.5 nm. A lithographic apparatus, which uses extreme ultraviolet (EUV) radiation, having a wavelength within the range 4-20 nm, for example 6.7 nm or 13.5 nm, may be used to form smaller features on a substrate than a lithographic apparatus which uses, for example, radiation with a wavelength of 193 nm.
It is desirable to make measurements of structures created in lithographic processes, e.g., for process control and verification. Various tools for making such measurements are known. Such tools may be referred to as metrology apparatuses.
Metrology apparatuses are known which rely on optical scatterometry. In such metrology apparatuses, an optical signal is obtained by measuring radiation scattered from a target. The optical signal may comprise intensity, phase, polarization, spectral information, or other optical properties. Parameters of interest describing properties of the target, such as overlay (OV), critical dimension (CD) or more complex shape parameters described structures of the target, are inferred from the optical signal. The optical signal is influenced by properties of the target and by properties of the metrology apparatus. It is necessary to distinguish between the two influences to determine the parameters of interest.
It is desirable to measure properties of the target consistently using different metrology apparatuses. This capability may be referred to as tool-to-tool matching. As Moore's law continues it is becoming increasingly difficult to achieve adequate tool-to-tool matching. This is particularly the case for sophisticated measurement modes, such as where different polarization modes or wide wavelength ranges are used, for small targets (e.g. 5×5 μm2 targets), and for difficult use cases, such as where sensitivity is low and/or where multiple parameters of interest with correlated responses are being determined.

Method of calibrating a plurality of metrology apparatuses, method of determining a parameter of interest, and metrology apparatus


A system for automatically identifying the desired concentrate to water ratio of a juice product in a concentrate container inserted into a juice dispenser and for automatically switching the ratio control system to the desired ratio. The system includes a product ratio I.D. member having ratio indicia on the fill plug of the container and a sensor in the dispenser. The sensed information is used by the ratio control system in the dispenser to change the pump motor speed to provide the desired ratio.

1. Field of the Invention
This invention relates to postmix beverage dispensers and in particular to a system for automatically identifying the desired concentrate to water mixing ratio of the product in a juice concentrate container loaded into the dispenser.
2. Description of the Prior Art
Postmix juice dispensers are well-known for mixing together a quantity of juice concentrate and water to produce a beverage. Different juice concentrates are mixed with water at different ratios. When changing from one concentrate to another that requires a different ratio, changes must be made in the dispenser to change the ratio. Different dispensers use different systems to achieve the desired ratio and also to change the desired ratio. One known system, where the ratio is controlled by the speed of a motor that drives a concentrate pump, requires the operator to manually actuate a switch. If this is not done, or is done incorrectly, then the beverage is dispensed at the wrong ratio and the beverage quality is not satisfactory.

Product identification system for beverage dispenser


A security monitoring, theft (and vandalism) prevention, and recovery system for automobiles includes an exterior light housing camera, an interior passenger cabin camera bar with an interior passenger cabin camera located within, an automatic release air valve located in a valve stem of an automobile wheel and tire assembly, and an automatic seatbelt immobilizing lock located in a seatbelt latch of an automobile. Upon detection of an invasive activity, an intrusion sensor provides an activation signal to a microprocessor. The exterior light housing camera and the interior passenger cabin camera are activated by the microprocessor to provide a video signal to the microprocessor via an activation signal. The quick release air valve and the seatbelt immobilizing lock are activated by the microprocessor to release air pressure from the wheel and tire and immobilize the seatbelt latch, respectively.

Motor vehicle theft is a term used for the criminal act of stealing or attempting to steal a motor vehicle such as an automobile, truck, bus, motorcycle, snowmobile, or trailer. Nationwide in the US in 2005, there were an estimated 1.2 million motor vehicle thefts with property losses estimated at $7.6 billion. There are many different types of anti-theft devices currently in the market to prevent or at least minimize motor vehicle theft losses including car alarms, steering wheel locks, brake pedal locks, wheel locks, and ignition immobilizers. While each of these devices has brought a level of success in reducing motor vehicle theft, using more than one method or device in combination is known to compound the effectiveness. The present invention features a security monitoring, theft (and vandalism) prevention, and recovery system for automobiles that captures video footage of a perpetrator and surrounding landmarks during a theft, restricts the mobility of the automobile, and restrains the perpetrator.

Automobile theft prevention and recovery system


A DC converter includes a time difference detector to detect a time difference between a point around which a main switch provides a minimum voltage after an auxiliary switch turns off and a point at which the main switch turns on, an integrator to integrate the output of the time difference detector, and a first delay circuit to control a turn-on point of the main switch according to the output of the integrator and the output of the time difference detector. The first delay circuit operates to minimize the output of the time difference detector according to the output of the integrator and controls a turn-on point of the main switch in a pulse-by-pulse manner according to a pulse-by-pulse control signal based on the output of the time difference detector.

1. Field of the Invention
The present invention relates to a DC converter with high efficiency and low noise.
2. Description of the Related Art
FIG. 1 shows a DC converter according to a related art. The DC converter of FIG. 1 employs an active clamp method and includes a DC power source Vin, a transformer T having a primary winding P1 (the number of turns is n1) connected to the DC power source Vin, and a main switch Q1 connected to the primary winding P1. The main switch Q1 is a MOSFET (hereinafter referred to as "FET"). Ends of the primary winding P1 are connected to a series circuit consisting of an auxiliary switch Q2 and a clamp capacitor C2. The auxiliary switch Q2 is a FET. The main switch Q1 and auxiliary switch Q2 have a dead time in which both of them are OFF. The switches Q1 and Q2 are alternately turned on/off under PWM control conducted by a controller 111.
The transformer T has the primary winding P1 and a secondary winding S1 (the number of turns is n2) that are wound to generate in-phase voltages. The secondary winding S1 is connected to a rectifying/smoothing circuit including diodes D10 and D11, a reactor L10, and a capacitor C10. The rectifying/smoothing circuit rectifies and smoothes a voltage (on/off-controlled pulse voltage) induced on the secondary winding S1 of the transformer T and provides a DC output to a load 30.
Based on the output voltage to the load 30, the controller 111 generates a control pulse signal to turn on/off the main switch Q1 and auxiliary switch Q2. In addition, the controller 111 controls the duty factor of the control signal so that the output voltage maintains a predetermined value.
The DC converter further includes an inverter 112, a bottom detector 113, a first delay circuit 114, and a second delay circuit 115.
The inverter 112 inverts a Q1 control signal Q1c, which is supplied from the controller 111 to control the main switch Q1, into a Q2 control signal Q2c and supplies it to the second delay circuit 115. The bottom detector 113 detects a minimum voltage (bottom voltage) of the main switch Q1 after the auxiliary switch Q2 turns off and provides a bottom detection signal Btm indicative of the bottom voltage.
The first delay circuit 114 delays a rise of the Q1 control signal Q1c from the controller 111 until a rise of the bottom detection signal Btm from the bottom detector 113, to generate a Q1 gate signal Q1g, which is applied to the gate of the main switch Q1 to drive the main switch Q1. The second delay circuit 115 delays a rise of the Q2 control signal Q2c from the inverter 112 by a predetermined time, to generate a Q2 gate signal Q2g and applies it to the gate of the auxiliary switch Q2, thereby driving the auxiliary switch Q2.
Operation of the DC converter with the above-mentioned configuration will be explained with reference to a timing chart of FIG. 2. In FIG. 2, a voltage Q1v is a drain-source voltage of the main switch Q1.
At t30, the Q1 control signal Q1c from the controller 111 rises to a high level, and the Q2 control signal Q2c falls to a low level. As a result, the Q2 gate signal Q2g becomes low to turn off the auxiliary switch Q2. The bottom detection signal Btm is low at t30.
After the auxiliary switch Q2 is turned off, the voltage Q1v of the main switch Q1 decreases. At t31, the bottom detector 113 detects a minimum (bottom) of the voltage Q1v. As a result, the bottom detection signal Btm from the bottom detector 113 becomes high, and after a vary short period of time, becomes low.
At t32, the first delay circuit 114 raises the Q1 gate signal Q1g to high to turn on the main switch Q1, thereby achieving bottom-voltage switching, or zero-volt switching of the main switch Q1.
When the main switch Q1 is turned on, a current from the DC power source Vin passes through the primary winding P1 of the transformer T and the main switch Q1. At this time, the rectifying/smoothing circuit passes a current through a route of S1, D10, L10, C10, and S1.
At t33, the Q1 control signal Q1c falls to turn off the main switch Q1. Energy accumulated in the primary winding P1 of the transformer T and in a leakage inductance between the primary and secondary windings of the transformer T charges a parasitic capacitor (not shown) of the main switch Q1, to produce a voltage resonance. As a result, the voltage Q1v of the main switch Q1 increases during a period from t33 to t34. The rectifying/smoothing circuit passes a current through a route of L10, C10, D11, and L10 to supply the current to the load 30.
At t34, the Q2 gate signal Q2g rises to turn on the auxiliary switch Q2. Energy accumulated in the primary winding P1 of the transformer T is supplied to the clamp capacitor C2 to charge the clamp capacitor C2. Energy accumulated in the clamp capacitor C2 passes through a route of C2, Q2, P1, and C2.


A customer information terminal for use in a retail grocery store includes a housing defining an interior region, electronic circuitry including a microprocessor supported within the housing interior region, and a display screen supported by the housing and electrically coupled to the electronic circuitry. The customer information terminal further includes a dataform reader module supported by the housing and electrically coupled to the electronic circuitry for reading a dataform having encoded data relating to at least one of the following; an item offered for sale in the retail grocery store, a coupon for an item offered for sale in the retail grocery store, a customer identification number of a customer of the retail grocery store, and a recipe utilizing one or more items offered for sale in the retail grocery store. Also provided is a radio module supported by the housing and including a transmitter system and a receiver system electrically coupled to the electronic circuitry for transmitting at least a portion of decoded data from the read dataform to a remote device and receiving from the remote device additional data related to the decoded data wherein at least a portion of the additional data is displayed on the display screen. The CI terminal further includes a user interface module supported by the housing for inputting a command whereby the radio module is utilized to obtain supplemental data from the remote device, the supplemental data relating to at least one of the decoded data and the additional data and wherein at least a portion of the supplemental data is displayed on the display screen. A method for using the CI terminal of the present invention is also disclosed.

Various dataform readers such as optical readers and optical scanning systems have been developed for reading bar code and matrix code dataforms imprinted on an item, an item's label, or an item's package or container. Bar codes and matrix codes are types of "dataforms" which are broadly defined here to include all arrangements whereby data is encoded in some form of machine readable copy. Thus, dataforms include one and two dimensional bar codes, matrix codes and graphic codes, as well as words and numbers and other symbols, which may be printed or etched on paper, plastic, plastic cards and other items.
Dataforms are extensively used in both manufacturing, product delivery, retail sales and service industries. In retail and grocery stores, a dataform imprinted on an item or its packaging includes a stock keeping unit (SKU) identifier encoded in the dataform. Upon being read by a dataform reader, the item's SKU is decoded. The SKU may be used for accessing a price for the item from a pricing file and, if the item is purchased, the SKU is used for updating appropriate inventory and accounting records to reflect the item's removal from inventory and record the revenue generated by the item's sale.
Dataform readers come in a variety of configurations. Some dataform readers are portable, that is, are carried around by an operator to read dataforms at the location of the items such as on a shop floor, in a warehouse or in a retail store. Other dataform readers are stationary, that is, the reader is rigidly support in one location such as a store check out counter and items whose dataforms are to be read are brought to the reader. A typical dataform reader reads a dataform by emitting light directed toward the dataform to be read. Light reflected from the dataform is sensed by a light sensitive sensor of the reader. By distinguishing between different reflective values of light from contrasting light and dark portions a dataform, the dataform can be decoded. For example, a one dimensional bar code dataform typically comprises black or dark colored bar type elements printed on a white or light colored background area, with white or light colored spaces between the bar elements of the bar code. A width of each bar element determines its value. Thus, upon analyzing the intensity of a pattern of reflected light, the dataform reader is able to distinguish between the varying width of the bar elements and output an electric signal whose magnitude varies with the intensity of the pattern of reflected light. Associated decoding circuitry decodes the electric signal into digital representations of the values encoded in the read dataform.
Providing bar code dataform readers for customer use is a recent development in the retail goods industry. Some retailers have installed "self-service" pricing terminals in their stores. Each pricing code dataform reader. A customer wishing to determine the price of an item places the item's dataform in a target area of the a dataform reader. The dataform reader reads the item's dataform, decodes the item's SKU, accesses a price of the SKU from a pricing file through a host computer and displays the price of the item on a display screen of the pricing terminal for the customer.
Each such pricing terminal in a store is hardwired to a network which is supported by the host computer. When a price of a particular SKU is changed in the pricing file, the old price is overwritten by the new price. As soon as the old price is overwritten, the new price will be displayed at a pricing terminal for any item having that particular SKU. There is no need to have the price stickers affixed to each item or change price stickers on every item corresponding to a given SKU when that SKU has a price change. Moreover, if sufficient pricing terminals are provided, it is not even necessary to mark the price of items corresponding to an SKU on a shelf where the items are displayed.
Unfortunately, installing a number of pricing terminal in a large retail store requires significant effort and cost in order to physically connect the pricing terminals to the network. As a sufficient number of pricing terminals must be placed throughout the store to allow convenient consumer access, it is often times necessary to extend existing network wires to areas which typically would not require nearby network access. Further, each time a pricing terminal needs to be added, removed or moved to a new location because of changing the layout of the store or other business need, significant costs and expenses would be incurred. Also, the information available from these terminals are generally limited to pricing information and do not allow the a customer to interact with the pricing terminal to receive additional information that may be desired by the customer. Thus, customers generally find using the pricing terminals to be burdensome in relation to the benefit derived especially since most stores continue to mark prices in convenient locations such as on items or on display shelves holding items.

Interactive customer information terminal


A printing device for providing multiple documents of one type includes a data receiving portion for receiving an image data, a processor, and a printing module. The processor is used to process the image data to generate a first printing information and a second printing information. The printing module is used to print a first document and a second document according to the first and second printing information, respectively. The first printing information includes the image data and a first identifying information, and the second printing information includes the image data and a second identifying information different from the first identifying information. The first identifying information is composed of a first set of halftone pattern, a first set of lines or a combining information thereof. The second identifying information is composed of a second set of halftone pattern, a second set of lines or a combining information thereof.

Field of the Invention
The present invention relates to a printing device, and more particularly, the present invention relates to a printing device for providing multiple documents of one type.
Description of Related Art
The conventional triplicate form is composed by carbon papers having different colors, and be printed information on the first sheet by a dot matrix type printer so as to duplicate the same information on the second and third sheets. However, the conventional triplicate form needs to be customized specially, and have higher cost. Wherein, the average cost of each triplicate form is about 0.78 NTD, and the ribbon of the dot matrix type printer must be replaced in use. Takes an example of a triplicate form which can be printed about 400 words, one ribbon can supply about 20000 triplicate forms for printing. The average printing cost of each triplicate form is about 0.02 NTD. Therefore, the total printing cost of the triplicate form is about 0.8 NTD.
In addition, the conventional dot matrix type printer has slow speed, noisy, and crooked or unclear print. Besides, the thickness of the triplicate form is thicker, which causes jams easily or can't feed smoothly. Thus, the problems about paper damage and reprinting requirement are occurred. Furthermore, the printed triplicate form needs to be separated for dispensing to all required units, and be with poor efficiency.

Printing device for providing multiple documents of one type