In accordance with the present invention, a gaming device includes a plurality of balances. The gaming device receives monetary input such as currency or a transfer from an account, and in turn increases one or more balances. The balance increased depends on criteria such as the amount of monetary input or the source (e.g. from a casino account). Players may draw wager amounts from different balances, and add award amounts to the balances. Incentives are provided for using the different balances. For example, different balances may have different payout schedules, different probability schedules, or both.

A conventional gaming device, such as a slot machine, video poker machine or video blackjack machine, typically requires a player to establish an initial "balance" by providing the gaming device with monetary input. For example, the player may insert currency (bills, coins and/or tokens) into the gaming device. Alternatively, the player may have funds transferred to the gaming device from an account, such as a credit card account or casino account that is identified by a card inserted into the gaming device. Once a balance is established, it is available for initiating a play of the gaming device.
The player then selects a wager amount which is subtracted from the balance (i.e. the wager amount is "drawn" from the balance), and initiates a play by pulling a handle or pressing a button on the gaming device. For example, the player may select a wager amount of three coins from a balance of ten coins. In response, the gaming device generates a game outcome (e.g. "CHERRY/CHERRY/CHERRY" for a slot machine) and a corresponding award amount that is based on the game outcome. The award amount may be zero for unfavorable game outcomes, or a greater amount for more favorable outcomes. Typically, greater award amounts correspond to more unlikely game outcomes. The balance is increased by the award amount, thereby generating an adjusted balance that is available for initiating a subsequent play of the gaming device.
After any number of such plays, the player may direct the gaming device to dispense the adjusted balance, thereby providing the player with monetary output. Dispensing typically includes activating a hopper in the gaming device to dispense currency to the player. Some gaming devices alternatively transfer the dispensed amount to a credit card account or other account, thereby eliminating the need for the player to hold and carry dispensed currency. After dispensing, the balance of the gaming device is zero, and another initial balance must be established before subsequent plays of the gaming device may be initiated.
If a player establishes a relatively large initial balance, he can enjoy many plays before the balance diminishes and more monetary input is required to continue. However, if the player establishes a relatively small initial balance, he must continually provide monetary input after each few plays. A player that establishes a small balance is likely to maintain a small balance during subsequent plays. He is in turn likely to "cash out" (have the balance dispensed as currency) if his award amounts increase the balance significantly.
Many players prefer to establish small balances, thereby retaining as much currency as possible. Players may do so in order to maintain physical control over their currency by holding it in their pocket or in a bucket. In addition, it is more convenient to retain currency for uses such as purchasing food or drinks from a cocktail server, tipping a cocktail server, or providing a companion with currency. In addition, it is inconvenient for the player to have to cash out each time he has to leave the gaming device (e.g. to get a drink, visit another player, or go to a rest room). Players may also worry that a power loss or similar electronic mishap will adversely affect the balance stored in the gaming device.
Conversely, casinos prefer that players establish large balances. Each time a player cashes out, he may decide to stop playing, particularly given the need to re-supply the gaming device with more monetary input. Further, the time spent dispensing the entire balance to the player and re-supplying the gaming device with monetary input is time during which no plays can occur. Accordingly, such time represents lost profits to the casino. In addition, dispensing currency exerts wear and tear on various components of the gaming device, and may eventually require repair and/or replacement of those components. Similarly, it is expensive for a casino to handle the vast amount of currency that is collected in its gaming devices. The casino must expend considerable resources in collecting, counting and moving coins, bills and tokens.
Casinos also prefer that players play from a large initial balance, rather than from repeatedly-inserted currency. Players tend to perceive a balance as somewhat less valuable than a corresponding amount of currency. Accordingly, players are more likely to continue playing as long as a balance remains, especially if the balance eventually decreases to a relatively small value. For example, if a gaming device with a minimum wager amount of $0.25 has a balance of $3, the typical player is more likely to play until the balance is reduced to zero, rather than cash out.
For similar reasons, casinos prefer that players use a casino account, rather than use currency or credit card accounts. Players that have a casino account have an incentive to continue playing at that casino rather than another. Further, while a player maintains a balance in a casino account, the casino has access to those funds and may, for example, derive interest payments therefrom. Even when funds are withdrawn from a casino account, they are used in a gaming device, and thereby become revenue for the casino.
Accordingly, when a player maintains a large balance or uses a casino account, the player essentially commits himself to a long session of play. The longer he plays, the greater the expected profit of the casino. Unfortunately, many players do neither. Conventional gaming devices do not provide any incentive for either maintaining a large balance or using a casino account.

Method and apparatus for controlling a gaming device having a plurality of balances

Walker Asset Management Limited Partnership


A supercapacitor is provided with a method for fabricating the supercapacitor. The method provides dried hexacyanometallate particles having a chemical formula AmM1xM2y(CN)6.pH2O with a Prussian Blue hexacyanometallate, crystal structure, where A is an alkali or alkaline-earth cation, and M1 and M2 are metals with 2+ or 3+ valance positions. The variable m is in the range of 0.5 to 2, x is in the range of 0.5 to 1.5, y is in the range of 0.5 to 1.5, and p is in the range of 0 to 6. The hexacyanometallate particles are mixed with a binder and electronic conductor powder, to form a cathode comprising AmM1xM2y(CN)6.pH2O. The method also forms an activated carbon anode and a membrane separating the cathode from the anode, permeable to A and A′ cations. Finally, an electrolyte is added with a metal salt including A′ cations. The electrolyte may be aqueous.

1. Field of the Invention
This invention, generally relates to electrochemical capacitors and, more particularly, to a supercapacitor made from a hexacyanometallate cathode, activated carbon anode, and aqueous electrolyte.
2. Description of the Related Art
A supercapacitor, or electrochemical capacitor (EC), constitutes one type of device for electrochemical energy storage and conversion. The electrochemical capacitor consists of two electrodes separated by an electrolyte-soaked separator by which the two electrodes are electrically isolated. Based upon the electrode type and the energy storage mechanism, the supercapacitor may be classified into one of the two following categories: (1) an electric double layer capacitor (EDLC), in which the energy is stored at the interface between the electrode and electrolyte through electrostatic charge accumulation, or (2) a pseudo-capacitor (or ultra-capacitor), whereby one electrode undergoes faradic reactions while the other electrode maintains the electrostatic charge accumulation.
In comparison to batteries and fuel cells, supercapacitors have the highest power density (watt per kilogram) due to the rapid movement of ions between the electrode and electrolyte. However, at the same time, the energy storage mechanism restricts its energy density (watt-hours per kilogram). Charge adsorption on the electrode surface dominates the energy storage in EDLCs. The performance of electrode materials can be evaluated by capacitance (F/g, Farad/gram), which can be defined as the charge accumulation with the voltage change per gram of electrode material: C=(ΔQ/ΔV)/m where Q is the accumulated charge, V is the voltage of the electrode materials, and in is the mass of the active materials of the electrode. The state-of-the-art commercial activated carbon materials have surface areas of 1000-3500 m2/g and capacitances of ˜200 F/g [L. L. Zhang, X. S. Zhao, "Carbon-based materials as supercapacitor electrodes", Chem. Soc. Rev., 38 (2009)2520-2531]. Physical adsorption of the electrostatic charge restricts the capacitance from further increases. Therefore, the introduction of faradic reactions to supercapacitors results in the so-called pseudo-/ultra-capacitors.
In general, pseudo-capacitors demonstrate much larger capacitances than EDLC because Faradic reactions can store charges both on the surface and in the bulk of the electrode materials. Ruthenium oxide (RuO2), for example, exhibits a high capacitance of 720 F/g [J. P. Zheng, P. J. Cygan, T. R. Jaw, "Hydrous ruthenium oxide as an electrode material for electrochemical capacitors", J. Electrochem. Soc., 142 (1995) 2699-2703] based upon the faradic reaction of RuOx(OH)y+zH++ze−←→RuOx−z(OH)y+z where the redox couple, Ru3+/4+, is reversible during the dis/charge process. Except for the appropriate redox couples, a robust material for the pseudo-capacitor electrode must demonstrate fast transport of charges and electrons in its structure(s), in order to ensure a high power density. Although Faradic reactions increase the capacitance of electrode materials significantly, both the transfer of charges and migration of ions result in a change of volume, which deteriorates their structure during cycling. For that reason, pseudo-/ultra-capacitors exhibit a shorter cycling life than EDLCs. Thus, more stable materials are actively being developing for this class of capacitor.
FIG. 1 depicts the crystal structure of a metal hexacyanometallate (prior art). Prussian blue analogues belong to a class of mixed valence compounds called transition metal hexacyanometallates. The hexacyanometallates have a general formula AmM1xM2y(CN)6, where M1 and M2 are transition metals. In many cases, the transition metal hexacyanometallates may contain a variety of ions (A=Co+, Na+, K+, NH4+, Co2+, Cu2+, etc.) and various amounts of water in the crystal structure. As is shown in the figure, the crystal structure of metal hexacyanometallates has an open framework which can facilitate fast and reversible intercalation processes for alkali and alkaline ions (Am). The number of alkali or alkaline ions in the large cages of this crystallographically porous framework may vary from m=0 to m=2 depending on the valence of M1 and M2.
Twenty years ago, Widmann, et al. demonstrated that K+-ions reversibly insert/deinsert into/from the copper, nickel, and iron hexacyanoferrates/hexacyanocobaltates Prussian blue analogues, KNiFe(CN)6, KCuFe(CN)6, and KFeFe(CN)6) in aqueous solution [A. Widmann, H. Kahlert, I. Petrovic-Prelevic, H. Wulff, Jr Yakhmi, N. Bagkar, F. Scholz, "Structure, insertion electrochemistry, and magnetic properties of a new type of substitutional solid solution of copper, nickel and iron hexacyanoferrates/hexacyanocohaltates", Inorg. Chem., 41 (2002) 5706-5715].
Eftekhari [A. Eftekhari, "Potassium secondary cell based on Prussian blue cathode", J. Power Sources, 126 (2004) 221-228] assembled an iron hexacyanoferrate (Prussian blue)/potassium battery with an organic electrolyte [1M KBF4 in ethylene carbonate/ethylmethyl carbonate (3:7 by wt.)]. The results proved that Prussian blue was a good electrode material for the potassium-ion battery with a reversible capacity of ca. 75 mAh/g.
Dr. Goodenough's group [Y. Lu, L. Wang, J. Cheng, J. B. Goodenough, "Prussian blue: a new framework of electrode materials for sodium battery", Chem. Commun. 52 (2012)6544-6546] investigated a series of Prussian blue analogues in a sodium battery with organic electrolyte, and found that KFe(II)Fe(III)(CN)6 demonstrated the highest capacity of ca. 95 mAh/g, while KMnFe(CN)6, KNiFe(CN)6, KCuFe(CN)6, and KCoFe(CN)6 demonstrated a capacity of 50˜70 mAh/g, in the first 30 cycles, the capacity retention of KFeFe(CN)6 was higher than 97%.
Very recently, Cui's group studied the Na+/K+ ion intercalation of copper (KCuFe(CN)6) and nickel hexacyanoferrates (KNiFe(CN)6) in aqueous solution. Their results demonstrated the rapid movement of Li+, Na+, K+, and NH4+-ions in the Prussian blue analogues, as well as long cycling life for the electrode materials [C. D. Wessells, R. A. Huggins, Y. Cui, "Copper hexacyanoferrate battery electrodes with long cycle life and high power", Nature Communication, 2 (2011) 550; C. D. Wessells, S. V. Peddada, R. A. Huggins, Y. Cui, "Nickel hexacyanoferrate nanoparticle electrodes for aqueous sodium and potassium ion batteries", Nano Lett., 11 (2011) 5421-5425; C. D. Wessells, S. V. Peddada, M. T. McDowell, R. A. Huggins, Y. Cui, "The effect of insertion species on nanostructured open framework hexacyanoferrate battery electrode", J. Electrochem. Soc., 159 (2012) A98-A103].
The fast ion movement makes it possible for the Prussian blue analogues to perform effectively as the electrode in supercapacitors. It is worth noting that iron ions at the M2 site in the above-mentioned materials remain at a high oxidation state (Fe3+) and the materials have to accept more intercalated ions to reduce the iron-ions (Fe2+), which requires the sources for the intercalated ions to couple the Prussian blue electrode. On the other hand, the Mn2+, Ni2+, Cu2+ and Fe2+ at the M1 site need a high voltage to deinsert the A-ion and to oxidize the M1 to the 3+ state. The voltage is so high that H2O decomposes in an aqueous electrolyte prior to oxidizing the M1. Therefore, only the Fe at the M2 site can perform the redox cycle (Fe2+/Fe3+) in an aqueous electrolyte for this supercapacitor application. If the Prussian blue analogues for a supercapacitor application have a high oxidation state (Fe3+) at the M2 site, the anode must source the supply of the intercalated ions. Cui's group, for instance, used a large, partially charged Prussian blue electrode as the counter electrode to provide a Na+ or K+ source. Therefore, it is impossible to use these materials in supercapacitors because the other electrode must be activated carbon, which cannot function as an ion-source for the Prussian blue analogues.
It would be advantageous if a supercapacitor could be fabricated using a Prussian blue cathode and an activated carbon anode.
For greater safety, it would be advantageous if the above-mentioned supercapacitor could be fabricated with an aqueous electrolyte.

Supercapacitor with hexacyanometallate cathode, activated carbon anode, and non-aqueous electrolyte


A device for holding portable electronics is disclosed. In one embodiment, the device comprises a base having a first end, and a second end, the first end positioned on one side of the base, and the second end positioned on a side of the base substantially opposite to the first end. The base has a plurality of apertures extending from the first end, through the base, to the second end; and at least one groove configured to receive an edge of the display. The device has a plurality of flexible legs configured to pass through an aperture in the base.

There are a variety of tablet computer accessory devices designed to hold a tablet computer hands-free (e.g., without the need for a user to hold the tablet computer with their hands or any other body part) and/or stationary in a variety of user situations. Of these existing devices, they can be divided into four broad categories.
Category A: This category represents devices that are generally intended to be used on a flat surface as a stand. They comprise, general a planar surface for contact with the flat surface and another surface projecting upward from the planar surface. Some devices in this category function as both covers and stands.
These aforementioned devices are used to prop-up a tablet computer for hands-free use. However, the devices in this category are limited in that they require a flat and stable surface for stability.
Category B: A second category of devices hold the tablet in an upright position, but without the need for a flat surface such as a table-top. In lieu of a flat surface, devices in this category are able to prop up tablets with the use of a body part of a user, such as the legs or lap of a user.
The devices in this category, unlike those in Category A, can be used without a flat and stable surface to rest the device on. They use various body parts of the user to maintain their stability. The limitation of the devices in this category is that the user must remain still to avoid movement of the device. When the body part that the device is resting on moves, so does the device, thus limiting the user's movement and ease of use.
Category C: The devices in this category are able to hold tablets in an upright position while the user is in a bed or chair, without having to rest it on the user's body part. This category shares some characteristics with those devices in both category A and B. Devices in this category have a piece that rests on an adjacent surface and a single arm to hold the tablet in place.
These devices allow tablets to be used while the user is in a bed or a chair, without having to rest the device on a body part, however the limitation of devices in this category is that while they allow tablets to be used in a bed or a chair, they still require an adjacent flat and stable surface for the piece of the device to rest on or be affixed to. As such, they are not useable in situations where an adjacent stable platform is not available. An additional limitation of this category of design is that due to the mount being suspended on a single arm/leg, there is a lack of stability when typing or otherwise using the touch-screen of the device being held; thus resulting in unwanted swaying or movement of the device.
Category D: This category addresses the limitations of all the previous categories in terms of using tablets in a bed or chair without either a flat resting surface or having to rest such devices on a body part. Instead, they depend on rigid arms resting on a surface to support tablets.
The devices in this category allow for a tablet computer to be used in a bed or a chair without the need to rest on a body part or have an additional flat or adjacent stable surface to rest the device on. However, the devices in Category D have several limitations.
First, the fixed plane configuration of the individual legs that support the device make them less than satisfactory, in terms of stability, for use on a bed or cushioned surface—especially one that may be exceptionally uneven on the surfaces where the legs rest. This results in a potential tilting of the viewing angle in the left-right axis that cannot be overcome, as the portion of the device that the tablet rests on is fixed to a 90 degree angle to the vertical plane of the supporting legs. If the legs are on uneven surfaces, then the left-right horizontal viewing axis will be tilted, resulting in a tilted viewing angle for the user.
A second limitation of category D designs are that they do not allow for a toward-the-face viewing angle that is less than 90 degrees. This prevents viewing a tablet device from a head-on direction while lying in a full supine position.
Attempts to overcome these issues have been unsuccessful. Some designs add a single-arm flexible neck which is attached to a central joining piece. However, the single-arm neck adds height to the whole assemblage and must be bent off center from the joining piece to place a tablet computer in a viewable position. This configuration gives the device a higher center of gravity, making it less stable and more top-heavy.
Other designs attach legs to the underside of a central joining piece, requiring the legs to make a 90° vertical turn upward into the body. This configuration uses more leg length than necessary for the function of the device. It also adds more extraneous height and bulk, making it clunky and giving it an awkward, less usable profile.
Further designs use gooseneck legs attached to the center body using male and female threaded ends. Given that the function of the gooseneck legs are made to be bendable into various shapes, the twisting and turning of the legs cause the threaded ends to easily loosen and twist inside of the central joining piece (i.e., become unscrewed), thereby reducing the devices functionality and usability.

This patent is subject to a terminal disclaimer.


A diffractive coupler coupling light between an opto-electronic element and a waveguide minimizes variation in coupling over an offset range, while providing good coupling efficiency. The offset range may be along the optical axis and/or radial. The diffractive coupler has a long depth of field and no best focus.

1. Field of the Invention
The present invention is directed to a diffractive coupler for use with a waveguide, especially for providing sufficient coupling within operational conditions.
2. Description of Related Art
There are many designs of optical couplers that couple light between an active element, e.g., a light source or a detector, and a waveguide, e.g., a fiber. Use of coupled systems in the field typically involves changing relative positioning between the transmitter/receiver and the waveguide. These changes may arise, for example, from vibrations in use, replacement or alteration of components in the system. Variations in coupling performance due to these changes are highly undesirable. They are generally referred to as "fiber wiggle."
One solution for reducing fiber wiggle includes actively aligning a coupling refractive lens, often an aspheric lens, in the z-direction, where z is along the fiber axis, to maximize the power being coupled. Then the lens is moved out of focus to create a larger spot. This larger spot allows coupling performance to be maintained within a desired range when the active element and the fiber are moved relative to one another in any direction. However, the larger spot reduces the coupling efficiency.
Alternatively or additionally, fiber wiggle may be reduced by decreasing the magnification of the lens performing the coupling. To achieve maximum coupling, the magnification of the lens matches the ratio between the numerical aperture of the active element and the numerical aperture of the fiber. However, due to this large magnification, small variations in the position of the active element appear as larger shifts on the fiber. By reducing this magnification, the apparent shift is smaller, making the system less sensitive to fiber wiggle. Again, this solution allows coupling performance to be maintained within a desired range when the active element and the fiber are moved relative to one another, but with reduced resultant coupling efficiency.

Diffractive coupler optimized for alignment tolerances


A detector and method for identifying a chemical vapor and determining its concentration in the ambient atmosphere. The chemical detector apparatus preferably includes a means of collecting vapors in one atmosphere and transferring the vapors by injection into a chromatographic separation column. The exit of the separation column is confined by a nozzle which causes the vapors to be focused into a specific area of an acoustic wave interferometer wherein standing waves are created by constructive interference of waves reflected from a plurality of reflecting elements. Identification of vapor species is by a combination of timed adsorption rate peaks and temperature programmed desorption rates of the individual vapor species.

In the analysis of chemical vapors there is frequently a need to detect extremely small trace amounts of a specific vapor amongst a background of different chemical species. Examples are the detection of contraband aboard the cargo of vessels being inspected by the United States Coast Guard and the detection of leaking explosive or dangerous chemicals at depositories thereof. Automated or portable testing apparatus for this purpose has generally not been available. Further, existing detectors are only able to detect chemical species at concentrations well above their ambient vapor concentrations and thus lack sufficient sensitivity.
Chemical sensors have been developed that physically change upon exposure and contain absorbing polymers selected for their affinity to absorb a group of related chemical species. One type, surface acoustic wave delay line sensors, are the most developed and readily available, for example, one commercial supplier is Microsensor Systems, Inc., Fairfax, Va.
A method and apparatus for using A SAW device to detect a vapor is disclosed by H. Wohltjen in U.S. Pat. No. 4,312,228, issued Jan. 26, 1982. As described therein, the SAW device comprises a piezoelectric element having a surface coated with a polymer material selected to absorb and react with the chemical to be detected. Interaction of the chemical with the material coating of the sensing element alters one or more properties of a surface acoustic wave, and the electrodes on the piezoelectric element detect the altered wave, producing an electrical signal.
Another apparatus and method for detection and identification of chemical vapors is disclosed in U.S. Pat. No. 4,895,017. As described therein a plurality of surface acoustic wave (SAW) devices, each coated with a selected polymer material are exposed to the vapor to be analyzed. In this invention a predicted time constant (or rate) of diffusion into the polymer coating is used to identify the different chemical species. To quantitatively identify specific chemical species present in vapors an array of SAW sensors with different polymer coatings may be exposed and a pattern recognition technique utilized to identify specific species. This is described in a paper entitled "Correlation of Surface Acoustic Wave Device Coating Responses With Solubility Properties and Chemical Structure" by D. S. Ballentine, Jr., S. L. rose, J. W. Grate, and H. Wohltjen, published in Analytical Chemistry, Vol. 58, P. 3058, December 1986.
A further patent using multiple polymer coated dispersive delay lines is disclosed by J. Haworth in U.S. Pat. No. 5,012,668, issued May 7, 1991. The use of specific absorbant polymers to sensitize the surface of a piezoelectric crystal and induce a phase or amplitude variation in a traveling acoustic wave is common to all of the prior art and this approach severely limits the performance of these vapor detectors. Multiple polymer films dilute the vapor samples and thereby limit the amount of vapor that can be detected by each film. Also, practically any type of film applied to the surface of a piezoelectric crystal introduces noise which reduces sensitivity further. None of the prior art provides an efficient method of transporting the vapors being analyzed to the surface of the sensing crystal. Nor does any of the prior art utilize the desorption characteristics of vapor species to identify individual vapor species.
There are Four problems with the procedures used for identifying chemical substances in the above described tests. First, the prior methods rely upon determination of the rate of diffusion and or equilibrium concentration of a chemical vapor absorbed into a coating on the surface of a SAW device. The time to identify a chemical species by chemical absorption of that species into a polymer film is too long for applications such as high speed chromatography, which require identification to be in seconds or milliseconds.
Second, previous polymer coated sensors and sensor arrays require that they be coated uniformly to insure unbiased readings. This requires that input vapor elements be diluted and divided between the absorbing polymer coatings equally. In many cases only trace amounts of material are available and therefore cannot be equally exposed to the sensors without an undesirable reduction in the sensitivity of the vapor detection apparatus.
Third, previous sensors do not interact directly with a well defined gas jet stream and require a manifold or distribution system to pass vapors to be detected to the acoustic sensor containment vessel, typically a vented TO-8 style integrated circuit package. This allows vapor containing gas to contact a significant amount of equal temperature surface areas not associated with the detection process. These surfaces adsorb and trap condensible vapors and reduce the amount of vapor material which can reach and be absorbed by the sensor's polymer coating.
Fourth, previous sensors require polymer coatings selective to a given species. These coatings introduce dissipation, attenuation and loss into the propagation path of the surface wave device and this causes lower signal to noise in the measurement of the surface wave velocity, phase, or amplitude. The low specificity of the polymer coating and sample dilution together increased noise and decreased sensitivity can cause an unacceptable number of false alarms.

Vapor detection apparatus and method using an acoustic interferometer


A method and device for displaying radio frequency information, including a database of stored radio frequency identifiers and radio frequency information corresponding thereto, and a processor coupled to the database and operating one or more algorithms for generating a display signal as a function of a correspondence between a decoded radio frequency identifier and one of the stored radio frequency identifiers.

Modern aircraft pilots must send and receive information to and from a large number of facilities. In particular, VHF radio signals are used by aircraft pilots for navigation. For example, VOR's (VHF Omni-directional ranges), localizers, LDA's, and SDF's are VHF radio signals that operate within the 108.00 to 117.95 MHz frequency band and have a power output necessary to provide coverage within an assigned operational service volume. The VHF navigation facilities that generate the VHF radio signals are subject to line-of-sight restrictions, and the range varies proportionally to the altitude of the receiving equipment.
Aircraft pilots are instructed to listen to the Morse Code identification of radio navigation stations to verify the correct VHF navigation facility has been tuned and that it is sending valid information. Most VOR facilities are equipped for voice transmission on the VOR frequency. VOR facilities without voice capability are indicated on navigation charts by an underline of the facility frequency. The voice capability may be used for two way communication with aircraft, for transmission of recorded flight information and for voice identification of the navigation station. Many Flight Service Stations (FSS) (or approach control facility) remotely operate several omniranges with different names. In some cases, none of the VOR facilities have the name of the "parent" FSS. Therefore, reliance on voice transmissions by the FSS involved for determining the identification of an omnirange is risky. During periods of maintenance, the facility may radiate a T-E-S-T code (- • •••-) or the code may be removed. The only positive method of identifying a VHF navigation facility is by decoding its Morse code identifier or monitoring the voice identification.
During operation of the aircraft, the pilot must identify the VHF navigation facility by mentally decoding an audio Morse code signal transmitted by the facility. Many pilots are not adept at performing this decoding operation, which often has to be performed during a high workload phase of flight. A single check, by the pilot, of the code at first use of the facility is not sufficient to detect a problem later in the flight. Continuos monitoring is necessary for the highest level of safety.
Systems that provide a radio Morse code identification function are in use and display the identification information in monochrome displays. While useful, such systems have limited functionality. Known Morse code identification systems typically sample the VHF navigation identifier at least twice to increase confidence of a correct decode. This increases the time before the identifier may be displayed to the pilot. Also, known Morse code identification systems do not correlate the decoded Morse code identifier with a specific VHF navigation facility, instead known systems only display a visual representation of the Morse code itself. When unable to decode the Morse signal, existing systems merely "dash" the display. These limitations increase the pilot's workload, and detract from safe aircraft operation and navigation.


A sonar system includes a forward looking array which is embedded in a cavitator for generating a gaseous cavity which minimizes hydrodynamic noise resulting from turbulent pressure fluctuations. A marine vessel incorporating the sonar system includes a hull, a hydrofoil suspended beneath the hull by a strut, and a cavitator for generating a laminar flow over the hydrofoil and for creating a cavity for eliminating turbulent flow contact. The cavitator is located at a leading edge area of the hydrofoil. The sonar array is embedded into the cavitator.

(1) Field of the Invention
The present invention relates to a sonar system which utilizes a gaseous cavity to eliminate hydrodynamic noise associated with turbulent boundary layers and turbulent wakes. More specifically the present invention relates to a sonar system that can be utilized on a hydrofoil marine vessel.
(2) Description of the Prior Art
Marine operators would like to operate high-frequency sonar systems from high speed surface craft. These craft can operate at speeds exceeding 30 knots, but they produce bubbly wakes (high frequency noise source), have noisy propulsors, and have noisy appendages. Sonar systems towed in or operating near their wakes are adversely affected by this generation of background noise, thus limiting their effective detection range.
A similar problem exists for very fast transport ships. Some futuristic concepts have been proposed which operate at speeds up to and exceeding 100 knots. The ability of these ships to maneuver at very high speeds is limited. Consequently, the ability to detect obstacles at significant range increases the ability of these craft to avoid collisions with marine mammals, mines, and debris.
Sonar systems towed at very high speeds are affected by several noise sources which may be controllable. The turbulent flow of water over the streamlined fairing of an array generates pressure fluctuations on the fairing. Both turbulent boundary layers and turbulent wakes contribute to this type of structural excitation. The pressure fluctuations can be experienced directly on the array when the flow over the array is turbulent, or indirectly as pressure fluctuations away from the sensor face are transmitted through the structure to the array. Fluctuating cavitation bubbles and collapsing vapor bubbles can also produce large structural excitations. The best way to minimize these types of hydrodynamic noise is to maintain laminar flow over the array face and to physically isolate the array face from portions of the structure experiencing large pressure fluctuations.
The vessel propulsion system produces a large amount of noise. Components of this noise include blade tonals, cavitation bubbles, and entrained air which produce noise that can propagate through the environment to the array. Similarly, breaking bow waves, hull slapping, ship machinery noise, and other ship related noise sources can reach the array through the environment. Isolating the array from these sources by eliminating the direct acoustic path between the source and the array would greatly improve the array performance.
A mechanical path from the noise source through the array supporting structure can create another acoustic problem for the array. However, mechanical isolation techniques are advanced and can minimize these effects.

Array system for supercavitating hydrofoils

The United States of America as represented by the Secretary of the Navy


A bicycle transmission includes a shaft, a driving part supported about the shaft for coupling to the input part, a driven part supported about the shaft for coupling to the output part, and a planetary gear mechanism disposed between the driving part and the driven part for changing the transmission ratio of the motive force applied from the driving part to the driven part. The planetary gear mechanism comprises a sun gear installed about the shaft, an output gear for transmitting motive force to the driven part, a frame part installed about the shaft and coupled to the driving part, and a planetary gear rotatably coupled to the frame part and disposed between the sun gear and the output gear for engaging the sun gear and the output gear. A clutch comprising a roller is disposed at an intermediate point along the transmission path between the driving part and the driven part for transmitting the motive force from the driving part to the driven part in one direction only. A first clutch of this type may be disposed between the output gear and the driven part, and a second clutch of this type may be disposed between the frame part and the driven part for directly coupling the frame part to the driven part. In another embodiment of the invention, the planetary gear mechanism further includes a switching unit for selectively coupling the frame part to the driving part and decoupling the frame part form the driving part In this embodiment, a first clutch of the above type may be disposed between the output gear and the driven part, a second clutch of the above type may be disposed between the frame part and the driven part, and a third clutch of the above type may be disposed between the driving part and the output gear.

The present invention is directed to internally mounted bicycle transmissions and, more particularly, to an internally mounted bicycle transmission which employs roller clutches in the transmission path
Internally mounted bicycle transmissions are installed inside the hub shell of the rear wheel of the bicycle and have the following main parts: (a) a fixed shaft which is fastened to the frame of the bicycle, (b) a planetary gear mechanism, (c) one-way clutches, and (d) an operating part. The planetary gear mechanism used in an internally mounted bicycle transmission with a conventional four-speed gear is constructed from (a) three sun gears which are installed around the outer circumference of the fixed shaft, (b) planetary gears which engage with the respective sun gears, and (c) a ring gear which engages with the planetary gears. The respective sun gears can be selectively coupled with the fixed shaft by means of the operating part. The planetary gears are supported by a gear frame which is installed on the outer circumference of the fixed shaft. In addition, respective one-way clutches are installed between the ring gear and the hub shell, and between the gear frame and the hub shell. The transmission ratio is altered by using the operating part to select that sun gear that is coupled to the fixed shaft. When no sun gear is coupled to the fixed shaft, the gear frame and the hub shell are coupled directly to each other.
Conventional one-way clutches used in internally mounted bicycle transmissions have a multiple number of ratchet pawl members which are installed (e.g.) between the ring gear and the hub shell. These ratchet pawl members are ordinarily long, slender members which pivot about one end. By pivoting and engaging with ratchet teeth on the hub shell, these ratchet pawl members transmit the motive force in one direction only.
In the case of idle rotation in the opposite direction from the direction of engagement, the ratchet pawl members pivot and strike the hub shell so that an impact sound is generated. This creates a significant amount of noise. Thereafter, when the system shifts from an idle state to an engaged state, it takes time for the ratchet pawl members to engage with the ratchet teeth, since the amount of play is relatively large. Moreover, since the ratchet pawl members and ratchet teeth engage abruptly, there is a considerable shock instead of a smooth transition. The same is true in the case of changing speeds. Thus, the switching of the one-way clutch cannot be performed in a smooth manner. This is especially true in the case of speed reduction where the pedals must be turned faster after the speed change than before the speed change. The amount of play seems to the cyclist to be amplified by the difference in the transmission ratio, thus aggravating the feeling of a lack of smoothness during the speed change.

Internally mounted bicycle transmission using roller clutches


A safety device comprises a body delimiting a passage having a safety rope passed through it, a ring connected by a strap to a belt, a brake and a system for locking the device to the rope should the worker fall. The device comprises a transverse spindle on which a toothed wheel is a relatively tight fit to constitute said brake, a cam mounted on the spindle and having teeth to cooperate with the safety rope and a weight cooperating with a pawl held away from a toothed ring attached to the cam by a spring, the weight being mounted in such a way that if the toothed wheel rotates at a speed greater than a specific threshold it causes engagement of the pawl with the toothed ring so that the cam teeth lock the safety rope into the passage.

1. Field of the Invention
The invention concerns safety devices for persons working at a great height.
The invention concerns devices which are movable along a safety rope running vertically up a wall of a building, a tower or a pylon.
2. Description of the Prior Art
These devices comprise a body having a passage through which the safety rope passes, a brake cooperating with the rope and a ring connected by a strap to a belt or a harness worn by the worker, said ring being combined with a system designed to lock the device onto the rope should the worker fall.
The ring is usually connected to a cam which wedges the safety rope against the opposite side of the passage if the traction force on the ring exceeds a particular value.
These devices are very well known and are totally effective. They do have some drawbacks, however. They must be mounted on the safety rope in a particular orientation because they work in only one direction and if the worker falls they lock up instantaneously, which may cause injury.
One object of the present invention is to remedy these drawbacks.


A tracking system employs magnetic resonance signals to monitor the position and orientation of at least one device such as a catheter within a subject. The device has a plurality of receiver coils which are sensitive to magnetic resonance signals generated in the subject. These signals are detected in the presence of magnetic field gradients and thus have frequencies which are substantially proportional to the location of the coil along the direction of the applied gradient. Signals are detected responsive to sequentially applied mutually orthogonal magnetic gradients to determine the device's position and orientation in several dimensions. The position and orientation of the device as determined by the tracking system is superimposed upon independently acquired medical diagnostic images. One or more devices can be simultaneously tracked.

1. Field of the Invention
The present invention relates to medical procedures in which a device is inserted into a body, and more particularly concerns tracking of such device with the use of magnetic resonance signals.
2. Description of Related Art
X-ray fluoroscopes are used routinely to monitor placement of devices during diagnostic and therapeutic medical procedures. Conventional X-ray fluoroscopes are designed to minimize X-ray dosage. Nevertheless, some procedures can be very long and the accumulated X-ray dose to the subject can become significant. The long term exposure of the attending medical staff is of even greater concern since they participate in these procedures regularly. Consequently, it is desirable to reduce or eliminate the X-ray dose during these procedures.
Another limitation on the use of X-ray fluoroscopes is that the technique is projective in nature and produces a single two-dimensional image. Information concerning the depth of an object within the field-of-view is not available to the operator. It is often desirable to obtain this information during surgical procedures.
Several method of using rf signals to track a device in the body have been disclosed in U.S. Patent Applications TRACKING SYSTEM TO MONITOR THE POSITION AND ORIENTATION OF A DEVICE WITH RADIOFREQUENCY FIELD GRADIENTS Ser. No. 07/753,565 by C. Dumoulin, R. Darrow, J. Schenck and S. Souza; TRACKING SYSTEM TO MONITOR THE POSITION AND ORIENTATION OF A DEVICE WITH RADIOFREQUENCY FIELDS Ser. No. 07/753,563 by C. Dumoulin, R. Darrow, J. Schenck and P. Roemer; STEREOSCOPIC X-RAY FLUOROSCOPY SYSTEM USING RADIO FREQUENCY FIELDS by C. Dumoulin and R. Darrow; AUTOMATIC GANTRY POSITIONING FOR IMAGING SYSTEMS Ser. No. 07/753,567 by C. Dumoulin and R. Darrow; and MULTI-PLANAR X-RAY FLUOROSCOPY SYSTEM USING RADIOFREQUENCY FIELDS Ser. No. 07/753,566 by R. Darrow and C. Dumoulin all filed on Sep. 3, 1991. These method do not require the use of X-rays but employs rf transmitting and receiving apparatus to track a device in a body.
Currently, there is a need for a simple method of tracking a device in an imaging system which requires little modification to the existing system and does not require X-ray radiation for tracking.

Tracking system to monitor the position and orientation of a device using multiplexed magnetic resonance detection


A reading machine includes computer program residing on a computer readable medium operable with an operating system that permits the production of windows on a display. The program has instructions for causing a computer to provide a first user selected call a first user selected routine in response to a user selecting a first word that the user seeks assistance in understanding and produce a text file for the first selected word comprised of data that assists the user call. An operating system routine commands the operating system to create a new window on the display and fill the new window on the display with the information contained in the text file. A second user selected call to a user selected routine can be provided for word that the user seeks assistance in understanding to provide a recursive enrichment feature.

This invention relates generally to educational tools and more particularly to reading machines which are used as part of a remedial reading program to assist individuals with learning disabilities or for reading machines for use by persons with severe visual impairments or blindness.
As it is known in the art, reading machines have been used to improve the educational attainment of individuals with learning disabilities. They have also been used by persons having visual impairment or blindness. In general, known reading machines are computer based. That is, the reading machines often include a personal computer having specialized software that provides a reading machine function to the computer. In addition, the reading machines include other PC type components such as a monitor, an audio system, a disk or mass storage device, and a keyboard. In general, specialized software processes an input source document and generates synthetic speech to enable a user to hear the computer read through the document a word, line, sentence etc. at a time. Often these reading machines include a scanner to provide one technique to input source documents to the reader.
Like any other computer-based system, often a user requires assistance in manipulating through a particular application. It is known that for many types of operating systems supported by computers, such as Windows,.TM. WindowsNT.TM. and Windows95.TM. from Microsoft Corporation, Redmond, Washington, on-line help features are typically available for the use of the operating system, as well as most if not all applications written for the particular operating systems. Generally, in a Windows-based application program, there are a plurality of pull-down menus. One of those pull-down menus is a Help menu, which when clicked on by a user provides various help-related options to the user. For example, the pull-down menu may include a search capability for a keyword, a table of contents, and so forth.
One of the problems associated with providing a Help feature in a computer-based reading machine system is that oftentimes, the user of the system, whether it be a blind individual or a person with learning disabilities, may not be able to obtain adequate help from the use of the conventional Help menu functions. This is because the conventional Help memory functions are text files which are displayed on the monitor. If the user is blind, this user would be unable to read the displayed text. Similarly, a person with learning disabilities that is using the reading machine to assist in reading may have a difficult time reading the text associated with the help feature. Similar problems also occur when a user desires to obtain a definition of a word. Accordingly, a new approach to provide enrichment function capabilities in reading machines is needed.

Reading system having recursive dictionary and talking help menu


A system and method are disclosed for providing journaling in a computer environment. An embodiment of the present invention comprises providing a first node and a second node; providing a journal wherein the journal is accessible by the first node and the second node; requesting a change in lock status by the first node; and executing a task by the second node in response to the request for the change in lock status by the first node.

Servers are typically used for big applications and workloads such as those used in conjunction with large web services and manufacturing. Often, a single server does not have enough power to perform the required application. To accommodate these large applications, several servers may be used in conjunction with several shared storage devices in a storage area network (SAN). In addition, it may be valuable to group servers together to achieve better availability or manageability.
As systems become large, it becomes more difficult to coordinate multiple component updates to shared data structures with high performance and efficient behavior. It would be beneficial to synthesize atomic updates on data structures spread over multiple data blocks when the hardware can only provide atomicity at the level of single block updates. The need for atomic update arises because systems can fail, and it can be costly or impossible to find and repair inconsistencies introduced by partially complete updates. One way to coordinate updates is through the use of a journal. The journal provides a mechanism to make updates atomic and durable.
What is needed is a system and method for managing a journal in a multi-node environment that can synthesize atomic updates to data structures spread over multiple data blocks. The present invention addresses such a need.

System and method for implementing journaling in a multi-node environment


Methods of forming a new wear and abrasion overlay formed with the steel surfaces of components for earth boring bits, and the components formed by the methods are disclosed. The overlay comprises a hard material particulate containing a metal carbide and an alloy steel matrix. The volume fraction of the hard material particulate in the overlay is greater than about 75%, the average particle size of the hard material particulate is between about 40 mesh and about 80 mesh, and the thickness of the overlay is less than about 0.050 inches. The process of manufacture includes the steps of fixing a monolayer of hard material particulate to the surface of a flexible mold, filling the mold with materials and powders, and CIP densifying to form a preform. The preform is then forged to near 100% density in a rapid solid state densification powder metallurgy process. The resulting bit component has an integrally formed overlay with superior physical properties.

1. Field of the Invention
This invention relates to erosion and abrasion resistant overlays on the steel surfaces of earth boring bits.
2. Description of the Related Art
SOLIDIFICATION HARDMETALS
Hardmetal inlays or overlays are employed in rock drilling bits as wear, erosion, and deformation resistant cutting edges and faying surfaces.
The strongest commonly employed hardmetals used in rock drilling bits are made by weld application of sintered tungsten carbide based tube metals or composite rods using iron alloy matrix systems. Heat input during weld deposition of such overlays is critical. Practical control limitations normally result in matrix variation due to alloying effects arising from melt incorporation of sintered carbide hard phase constituents as well as substrate material. Partial melting of cemented carbide constituents results in "blurring" of the hard phase boundaries and the incorporation of cobalt and WC particles into the matrix. Process control is typically challenged to maintain "primary" hardmetal microstructural characteristics such as constituency and volume fraction relationships of hard phases. Secondary characteristics such as matrix microstructure are derivative and cannot be readily regulated.
These overlays typically comprise composite structures of hard particles in a tough metal matrix. The hard particles may be a metal carbide, such as either monocrystalline WC or the cast WC/W.sub.2 C eutectic, or may themselves comprise a finer cemented carbide composite material. Often, a combination of hard particle types is incorporated in the materials design, and particle size distribution is controlled to attain desired performance under rock drilling conditions, such as disclosed in U.S. Pat. No. 3,800,891, No. 4,726,432 and No. 4,836,307.
The matrix of these hardmetal overlays may be iron, nickel, cobalt, or copper based, but whether formed by weld deposition, brazing, thermal spraying, or infiltration, the matrix microstructure is necessarily a solidification product. During fabrication, the hard phase(s) remain substantially solid, but the matrix phase(s) grow from a melt during cooling and thus are limited by thermodynamic, kinetic, and heat transport constraints to narrow ranges of morphology, constituency and crystal structure.
Welded composite hard metals encounter several limitations when large areal coverage is needed such as in continuous overlays of bit cutting faces as shown in FIGS. 1 and 2. Foremost of these is the high cost of application. Also, compatibility issues provide physical limits arising from property differentials between substrate materials and overlays, and fabrication logistics become limiting due to thermal stability issues with substrate or cutting elements. These factors have limited welded composite rod hardfacing overlays to crest and flank locations of tooth type roller cone bit cutting structures, and have precluded their use in interference fitted (insert type) roller cone bit cutting structures.
Welded overlays have been incorporated for large areal protection of faces and gage surfaces of drag type polycrystalline diamond composite (PDC) bits. However, necessary compromises in coverage, constituency, and application method have rendered the performance/cost relationship marginal for many PDC products.
Welded hardmetal overlays are commonly used for protection of lug "shirttail" locations of both tooth and insert of roller cone bits, although coverage is necessarily selective, due to cost and the tendency to crack which increases with areal coverage.
Due to the aforementioned limitations, practice in both insert type roller cone and PDC drag bits has gravitated to thermal spray carbide composite coatings for erosion and abrasion protection of large areas. Various thermally sprayed coatings for drill bits are disclosed in U.S. Pat. Nos. 4,396,077; 5,279,374; 5,348,770; and 5,535,838. These coatings are typically too thin, too fine grained, and too poorly bonded to survive long in severe drilling service. In addition, consistency of thermal spray coatings is notoriously variable due to process control sensitivity and geometric limitations during application. Finally, like weld applied hardmetals, thermal spray coatings are similarly limited to solidification microstructures and subject to other process related microstructural constraints.
SOLID STATE HARDMETALS
The development of solid state densification powder metallurgy (SSDPM) processing of composite structures has enabled the fabrication of hardmetal inlays/overlays which potentially include a range of compositions and microstructures not attainable by solidification. In addition, SSDPM processing methodology also provides more precise control of macrostructural and microstructural features than that attainable with fused overlays, as well as lower defect levels. Such methods and resulting full coverage products are described in U.S. Pat. Nos. 4,365,679; 4,368,788; 4,372,404; 4,398,952; 4,455,278; and 4,593,776. However, the relatively slow hot isostatic pressing densification method entails onerous economic implications. It also is restricted to thermodynamically stable materials systems, effectively limiting the potential novelty attainable in composition and microstructure.
The advent of rapid solid state densification powder metallurgy (RSSDPM) processing of composite structures has enabled the fabrication of hardmetal inlays/overlays which include a much broader range of possible compositions and microstructures, as well as more favorable process economics. RSSDPM processing entails forging of powder preforms at suitable pressures and temperatures to achieve full density by plastic deformations in time frames typically of a few minutes or less. Such densification avoids the development of liquid phases and limits diffusional transport. For example, RSSDPM processing can be achieved by filling a flexible mold with various powders and other components to about 55% to 65% of theoretical maximum density, then compressing the filled mold in a cold isostatic press (CIP) at high pressure to create an 80% to 90% dense preform. This preform is then heated to about 2100 degrees F. and forged to near 100% density by direct compression using a particulate elastic pressure transmitting medium. Alternately, the final densification may be achieved by other rapid solid state densification processes, such as the pneumatic isostatic forging process described in U.S. Pat. No. 5,561,834.
Because the components are densified in stages, the size of the preform is significantly smaller than the interior of mold, and the finished part is significantly smaller than its corresponding preform, although each has about the same mass.
RSSDPM processing provides more precise control of microstructural features than that attainable with either fused overlays or slow-densified PM composites. Such fabrication methodologies for rock bits are disclosed in U.S. Pat. Nos. 4,554,130; 4,592,252; and 4,630,692. Shown in these patents and also in U.S. Pat. Nos. 4,562,892 and 4,597,456 are examples of drill bits with wear resistant hardmetal overlays which exploit the flexibility and control afforded by RSSDPM. None of these patents, however, teach or anticipate process-derived physical and microstructural specificity intrinsic to RSSDPM fabrication methods. Nor do they teach economic methods for fabrication or formulation strategies for optimization of full coverage RSSDPM inlays as a function of bit design and application.
Although many unique hardmetal formulations are made possible by RSSDPM, most will not be useful as rock bit hardmetal inlays because they lack the necessary balance of wear resistance, strength, and toughness. In addition, straight forward substitution of RSSDPM processing has been found to produce hardmetals which behave differently in service than their solidification counterparts. Some have exhibited unique failure progressions which disadvantage them for use in drilling service.
For example, a RSSDPM "clone" of a conventional weld applied hardmetal made from 65 wt. percent cemented carbide pellets (30/40 mesh WC-7% Co), and 35 wt % 4620 steel powder, was found to have lower crest wear resistance than expected due to selective hard phase pullout caused by shear localization cracking in the matrix. The presence of sharpened interfaces combined with the formation of ferrite "halos" around carbide pellets propitiates deformation instability under high strain conditions. Even though the primary characteristics normally used to evaluate hardmetal (volume fractions, pellet hardness, matrix hardness, and porosity) were superior to conventional material, the RSSDPM clone exhibited an unexpected weakness.
Other experimentation with RSSDPM hardmetal in drilling service has partially refuted conventional wisdom that maximization of volume fractions of hard phase increases robustness of cutting edges. In hard formations/severe service, tooth crests formulated with high carbide loading made possible with RSSDPM methods were found to be vulnerable to macro scale cracking. However, in locations where high velocity fluid erosion dominates such as water courses and jet-impinged cutter faces, carbide loading and particle size were pushed beyond conventional limits with increasing benefit.
In U.S. Pat. No. 5,653,299, a particular hardmetal matrix microstructure which is very advantageous for rolling cutter drill bits is shown. RSSDPM processing provides a cost effective, controllable way of achieving this matrix microstructure.
Optimization of RSSDPM hard metals entails consideration of both process derived and design derived specificities. The physical demands placed on hard metals differ with location on a bit, and are dependent on bit design characteristics as well as application conditions. In particular, the hardmetal formulations best suited to resist deformation, cracking, and wear modes operative at cutting edges or tooth crests are not optimal to resist abrasion, erosion, and bending conditions operating on cutter or tooth flanks. In turn, hardmetal formulations optimized for bit faces, watercourses, and gage faces will be similarly specific to local erosion, abrasion, wear, and deformation conditions.
POWDER METALLURGY FABRICATION METHODS
Forged, powder metal fabricated rock bits have been developed which incorporate composite powder preforms in the cold isostatic press (CIP) portion of the fabrication cycle in order to produce RSSDPM hardmetal inlays. U.S. Pat. No. 5,032,352, herein incorporated by reference, describes in detail a RSSDPM process particularly applicable to making components for earth boring bits. In particular, the patent describes the method of incorporating previously formed inserts in a mold prior to a CIP densification cycle to form a hardmetal inlay in the finished part. The inserts are usually molded using a powder binder mix in separate tooling.
One preferred method of making these mold inserts employs a metal injection mold process using sintered WC-Co cemented carbide particulate and steel powder bound with an aqueous polymeric fugitive binder such as methylcellulose. The resulting previously formed inserts are inserted into tooth recesses in the elastomeric CIP mold prior to filling with steel powder. After forging, the inserts become fully dense integral hardmetal inlays which can exhibit constituencies covering and exceeding ranges those attainable by various solidification means.
While forming a hard metal layer utilizing preformed insert structures offers performance potential not available via conventional processes, incorporation of preformed inserts requires close conformation to the flexible mold features, in order to provide dimensional control. This entails precision preform fabrication tooling and associated design effort. In addition, practical molding limits on section thickness, aspect ratios, and particle size and volume loading of carbide prevent very thin, very large, and very dense preformed inserts such as may be desirable to achieve the most cost effective and/or functional cutter overlay configurations.
In a completely different fabrication technology (infiltration), U.S. Pat. No. 4,884,477 describes the use of a fugitive adhesive on rigid female mold tooling for incorporation of hard material particulate species to achieve a superficial composite hard metal in PDC drag bit heads. This type of infiltration process typically uses a copper based binder material which melts at a temperature less than about 1000 degrees C. The melted binder fills the spaces between the powders packed within the mold and produces a part which has substantially the same dimensions as the interior of the mold. Also, copper based matrices exhibit lower yield strength and modulus of elasticity than those of the steel alloy matrices available in RSSDPM, making the infiltrated product inferior in service, particularly where significant strains are applied to the product in service. Also, in an infiltration process, the maximum practical attainable volume fraction of hard material particulate is limited to about 70 volume percent due to packing density limitations. Typically the volume percent actually attained is lower than 70%. This limits the wear and erosion resistance of the surface of the infiltrated product.
There is a need for a tough and very wear, abrasion and erosion resistant coating for the steel surfaces of drill bits. Preferably the coating will have a very high volume percent hard material particulate for good wear, abrasion and erosion resistance, and have a steel alloy matrix for strength and toughness. Ideally, the coating would be economical to form, even over large areas of the steel surfaces.

Rock bit hardmetal overlay and process of manufacture


A label according to the invention reduces waste, has a lower cost, yet maintains a high level of consumer friendliness. In one embodiment, a label according to the invention uses adhesive rails in order to reduce the amount of adhesive and also places a confusion on a release layer in order to eliminate a downsheet. According to another embodiment, a label has a first layer of pressure sensitive adhesive for securing the label to a substrate but has a second layer of adhesive formed of a remoistenable gum to allow the consumer to later secure a collectable component to another substrate. In a further embodiment of the invention, a collectable component of a label has a release placed on one portion of its outer side and a repositionable adhesive placed on a second portion of its outer side. This label is consumer friendly in that it uses a pressure sensitive adhesive and since it allows a consumer to fold the collectable component in half before securing it to another substrate. In a further embodiment, a label is formed of two layers of paper and is secured to a substrate with a release liner placed between the collectable component and the substrate. The user may remove the collectable component from its substrate and then remove the liner when the consumer is ready to place the component on another substrate.

Many fast food restaurants as well as other retailers have games, promotions, giveaways, or other such events in order to lure customers into purchasing their goods. Oftentimes, labels are secured to the goods and the customers must purchase the goods in order to participate in the game. The game piece itself is typically hidden from view within the label and the customer must remove part or all of the label in order to view the game piece. The game piece may be a collectable item in which the customer tries to collect an entire set or the game piece may be redeemed to the vendor, for instance, in order to receive free goods or prizes.
An example of a label having such a game piece is shown and described in U.S. Pat. No. 5,653,473 to Laszutko et al., which is hereby incorporated by reference. With reference to FIGS. 1A to 1C, a label 10 described in the Laszutko et al. patent includes a first label composite 20 and a second label composite 22. The first label composite 20 includes a face layer 26 and a release layer 27 which is formed of a liner 28 and a release coating 29. The face layer 26 and release layer 27 are laminated together with a pressure-sensitive adhesive layer 30. The second label composite 22 also includes a face layer 34 and a release layer 35 which is formed of a liner 36 and release coating 38. The face layer 34 is laminated to the release layer 35 with a pressure-sensitive adhesive layer 40. The first and second label composites 20 and 22 are laminated together with an adhesive 42 and are positioned relative to each other so that surface 52 of the face layer 26 is in contact with surface 54 of face layer 34. The adhesive 42 is applied between the label composites 20 and 22 only in adhesive bar sections 14.
In use, the release layer 27 is peeled away from the rest of the label 10 and the face layer 26 is secured to a substrate with the pressure-sensitive adhesive layer 30 with this substrate, in one example, being a beverage cup. A customer who purchases the cup having the label 10 pulls a tab section 12 of the label 10 in order to separate the second label composite 22 from the face layer 26 of the first label composite 22. The label 10 has perforations 43 which are formed entirely through the second label composite 22 and partially through the first label composite 20 in order to assist in the removal of the second label composite 22. A front 54 of the face layer 34 may include printing in order to form the collectable component of the label 10. If desired, the customer may remove the release layer 35 to expose the adhesive layer 40 and then secure the collectable component to a game board or other surface. The second label composite 22 includes a cut line 45 to assist in the removal of the release layer 35 from the adhesive layer 40.
A typical label, such as label 10 shown in the Laszutko patent, is relatively expensive to manufacture. The label is generally a four-ply label with two of the plies being made from glossy paper stock and the other two plies being release layers, which may be formed of conventional paper or polymer stock coated with a release agent. The label also includes two complete layers of a pressure-sensitive adhesive. All of these layers and materials are rather expensive. A layer of the pressure-sensitive adhesive, for instance, is actually more expensive than one of the plies of paper, such as roughly 1.5 times the cost of the paper. A release layer is even more expensive than both the paper and the pressure-sensitive adhesive with its cost being approximately three times that of a single ply of paper. The use of two release layers and two layers of the pressure-sensitive adhesive therefore substantially increases the cost of the label.
In addition to expense, other problems of a typical label relate to its consumer friendliness. Some of the conventional labels have been difficult to remove from the supporting substrate, such as a beverage cup. When the customer attempts to remove the label, the customer inadvertently tears or otherwise damages the label itself. Once removed, customers have had difficulty in handling the labels or game pieces. For example, some game pieces are difficult to collect since they are not easily secured to a game board. Other game pieces, in contrast, have an adhesive layer exposed once the game piece is removed from the cup. These game pieces, however, are undesirable since the customer must immediately secure the game piece to the game board, which may have been left at home or at a different location.

Multi-ply labels having collectable components


A patterning area of an output circuit is reduced while securing strong enough ESD tolerance. In the output circuit of this invention, an output of a first amplifier and an output of a second amplifier are connected to a common output pad. Each of the amplifiers is driven by each of signals Φ1 and Φ2 from an internal circuit, respectively. The first amplifier has larger driving capacity than the second amplifier. A high voltage side power supply terminal of the second amplifier is provided with a power supply voltage VDD from a power supply pad through a first protection resistor, while a low voltage side power supply terminal of the second amplifier is provided with a ground voltage VSS from a ground pad through a second protection resistor. And a third protection resistor is connected between an output of the second amplifier and an output terminal. The first, second and third protection resistors are made of metal wirings, and their resistance is preferably about 10Ω.

1. Field of the Invention
This invention relates to an output circuit, specifically to an output circuit that includes at least two amplifiers.
2. Description of the Related Art
In general, ESD (Electrostatic Discharge) damage is caused in a MOS transistor when an excessive voltage due to an external noise is applied to it. Therefore, various protection measures are taken especially for a MOS transistor connected to an input or output terminal. In an output circuit shown in FIG. 8, an output of a first amplifier 1 and an output of a second amplifier 2 are connected to a common output pad (output terminal) P2. Each of the amplifiers 1 and 2 is driven by each of signals Φ1 and Φ2 from an internal circuit 3, respectively. The first amplifier 1 has a larger driving capacity than the second amplifier 2. Driving capacity of the combined amplifiers can be made variable by controlling the amplifiers so that either the first amplifier 1 or the second amplifier 2 is in operation, or both of the amplifiers 1 and 2 are in operation.
A high voltage side power supply terminal H1 of the first amplifier 1 is provided with a power supply voltage VDD from a power supply pad P1, while a low voltage side power supply terminal L1 of the first amplifier 1 is provided with a ground voltage VSS from a ground pad P3. Similarly, a high voltage side power supply terminal H2 of the second amplifier 2 is provided with the power supply voltage VDD from the power supply pad P1, while a low voltage side power supply terminal L2 of the second amplifier 2 is provided with the ground voltage VSS from the ground pad P3.
Each of the first amplifier 1 and the second amplifier 2 includes a CMOS inverter composed of a P-channel type MOS transistor and an N-channel type MOS transistor. The MOS transistors in the first amplifier 1 are designed to be larger in size (gate width GW) than the MOS transistors in the second amplifier 2, so that ON-resistance of the MOS transistors in the first amplifier 1 is lower than that in the second amplifier 2.
Also, in order to prevent ESD damage on the MOS transistors by an external noise applied to the power supply pad P1, the output pad P2 or the ground pad P3, a size of a contact hole of the MOS transistor connected directly to each of the pads, a distance between the contact hole and the gate, a gate length and a distance between a back gate and a source or a drain in both of the first and second amplifiers are designed to be of considerably larger sizes (ESD protection design rules) than minimum sizes according to design rules applied.
Further information related to the technologies described above is disclosed in Japanese Patent Application Publication No. H05-335493, for example.
However, designing both the first amplifier 1 and the second amplifier 2 to the ESD protection design rules results in increased sizes of the MOS transistors that constitute the amplifiers, and causes a problem of larger die size of the LSI (Large Scale Integration) in which the amplifiers are included.


A communication system is disclosed that allows high data-rate transmission of data between components. N-bit parallel data is transmitted in K-frequency separated channels on the transmission medium so as to fully take advantage of the overall bandwidth of the transmission medium. Additionally, a cross-channel interference filter in a receiver section corrects for cross-channel interference in the communication system. As a result, a very high data-rate transmission can be accomplished with low data-bit transmission on individual channels. A transmitter system and a receiver system are described for the communication system.

1. Field of the Invention
The present invention is related to high-speed communications of data in a communication system and, in particular, to high data rate transmission of data between components in a communication system.
2. Discussion of Related Art
Many conventional systems for transmitting data between components within a cabinet or between cabinets of components utilize copper or optical backplanes for transmission of digital data. For example, high data rate transceiver systems are utilized in many backplane environments, including optical switching devices, router systems, switches, chip-to-chip communications and storage area networking switches. Other environments that utilize high speed communication between components include inter-cabinet communications and chip-to-chip communications. Typical separations of components in such systems is between about 0.1 and about 10 meters.
Existing techniques utilized in such environments typically use non-return to zero (NRZ) modulation to send and receive information over high-speed backplanes or for high data rate chip-to-chip interconnects. Typically, the transceiver for sending high-speed data over a backplane is called a serializer/deserializer, or SERDES, device.
FIG. 1A shows a block diagram of a backplane environment 100. Components 101-1 through 101-Q are coupled to transmit and receive data through input/output (I/O) ports 102-1 through 102-Q, respectively, to backplane 110. Conventionally, components 101-1 through 101-Q are SERDES devices.
FIG. 1B shows a block diagram of a conventional transmitter portion of one of SERDES devices 101-1 through 101-Q on I/O ports 102-1 through 102-Q, respectively. Parallel data is received in a bit encoder 105. Bit encoder 105 encodes the parallel data, for example by adding redundancy in the input data, to ensure a minimum rate of data transitions in the output data stream. Typical encoding schemes include rate 8/10 (8 bit input to 10 bit output) encoding. The parallel data is serialized in parallel to serial converter 106. Output driver 107 then receives the serialized data from parallel to serial converter 106 and outputs, usually, a differential voltage signal for transmission over backplane 110. In addition, there is typically a phase locked loop (PLL) 114 that provides the necessary clock signals for encoder 105 and parallel-to-serial converter 106. The input signal to PLL 114 is a reference clock signal from a system PLL 103.
FIG. 1C shows a conventional receiver 108 of one of SERDES devices 101-1 through 101-Q on I/O ports 102-1 through 102-Q, respectively, of FIG. 1A. Input driver 109 receives differential voltage signal from backplane 110 and outputs the analog data signal to clock and data recovery circuit 113. Data recovery 113 can, in some systems, perform equalization, recover the timing and output a serial bit stream of data to serial-to-parallel converter 111. The serial data is input to bit decoder 112 which converts the parallel data to parallel decoded data. Clock and data recovery circuit 113 also outputs the necessary clock signals to serial-to-parallel converter 111 and bit decoder 112.
A conventional SERDES system 100 can enable serial data communication at data rates as high as 2.5 Gbps to 3.125 Gbps over a pair of FR4 copper traces in a copper backplane communication system. One of the biggest problems with existing SERDES systems 100 is that they are very bandwidth inefficient, i.e., they require 3.125 GHz of bandwidth to transmit and receive 2.5 Gbps of data over a single pair of copper wires. Therefore, it is very difficult to increase the data rates across backplane bus 110. Additionally, SERDES system 100 requires the implementation of a high clock rate (3.125 GHz for 2.5 Gbps data rates) phase locked loop (PLL) 114 implemented to transmit data and recover high clock rates in data recovery 113. The timing window within which receiver 108 needs to determine whether the received symbol in data recovery 110 is a 1 or a 0 is about 320 ps for the higher data rate systems. This timing window creates extremely stringent requirements on the design of data recovery 113 and PLL 114, as they must have very low peak-to-peak jitter.
Conventional SERDES system 100 also suffers from other problems, including eye closure due to intersymbol interference (ISI) from the dispersion introduced by backplane 110. The ISI is a direct result of the fact that the copper traces of backplane 110 attenuate higher frequency components in the transmitted signals more than the lower frequency components in the transmitted signal. Therefore, the higher the data rate the more ISI suffered by the transmitted data. In addition, electrical connectors and electrical connections (e.g., vias and other components) used in SERDES device 100 cause reflections, which also cause ISI.
To overcome these problems, equalization must be performed on the received signal in data recovery 113. However, in existing very high data-rate communication systems, equalization is very difficult to perform, if not impossible due to the high baud rate. A more commonly utilized technique for combating ISI is known as "pre-emphasis", or pre-equalization, performed in bit encoder 105 and output driver 107 during transmission. In some conventional systems, the amplitude of the low-frequencies in the transmitted signal is attenuated to compensate for the higher attenuation of the high frequency component by the transmission medium of bus 110. While this makes the receiver more robust to ISI, pre-emphasis reduces the overall noise tolerance of transmission over backplane 110 of backplane communication system 100 due to the loss of signal-to-noise ratio (SNR). At higher data rates, conventional systems quickly become intractable due to the increased demands.
Therefore, there is a need for a more robust system for transmitting data between components on a backplane or data bus at very high speeds.

High-speed multi-channel communications transceiver with inter-channel interference filter


A bracket assembly for coupling a component to a vehicle including a bracket body including a C-ring retainer that is adapted to translatably engage and retain a T-shaped guide rail coupled to one of a crossmember and floor structure of the vehicle, wherein the bracket body defines a hole or includes an attachment structure adapted to receive and retain the component. The bracket body further includes one or more flanges adapted to secure the bracket body to the crossmember or floor structure of the vehicle via bolting and/or welding. Optionally, the bracket body includes: a front attachment arm; a rear attachment arm; one or more intervening structural reinforcement members; a bottom portion coupled to the attachment arms; and a cap structure coupled to the attachment arms opposite the bottom portion; wherein the bottom portion includes the C-ring retainer and the cap structure defines the hole or includes the attachment structure.

Typically, seat components are secured in a vehicle using one or more pivot brackets or the like that are manufactured from steel and bolted and/or welded to the floor structure of the vehicle and, in the case of many front and rear seats, a crossmember that traverses the width of the vehicle. This floor structure and crossmember may also be made of steel. The seat components (or other components) are then bolted or otherwise coupled to these pivot brackets or the like, thereby securing the seat components (or other components) in the vehicle.
This conventional set-up is illustrated in FIG. 1. Here, the pivot bracket 10 includes a front attachment portion 12 that is adapted to be bolted and/or welded to the floor structure 13 and a rear attachment portion 14 that is adapted to be bolted and/or welded to the crossmember 15. The front attachment portion 12 and the rear attachment portion 14 are joined by a bottom portion 16 that runs substantially conformally along the intervening surfaces of the floor structure 13 and crossmember 15. One or more flanges 18 protrude perpendicularly from the front attachment portion 12, the rear attachment portion 14, and the bottom portion 16 of the pivot bracket 10 to facilitate this bolting and/or welding to the floor structure 13 and cross-member 15, providing enhanced contact surface area.
The pivot bracket 10 also includes one or more holes 20 formed in a top portion thereof configured for coupling to the seat components (or other components) of the vehicle. In the set-up illustrated, the pivot bracket 10 is adapted to receive a seat of the vehicle and is disposed adjacent to an associated Isofix bracket 22, for example.
Although such set-up is strong, it is relatively heavy and generally does not provide the desired degree of durability and ease of manufacturing. Thus, an improved set-up is still needed in the art.

Lightweight c-ring crossmember and bracket assembly for a vehicle


A battery charging circuit, particularly useful in a laptop computer system, includes a voltage input terminal coupled to a dc voltage. A first switch couples the voltage input terminal to an output coupled to the battery through a current sense resistor. A first current sink which is on when the charger circuit is on draws current from the input side of the current sense resistor through a first resistor to develop a first voltage. This voltage and a voltage coupled through a second resistor from the battery side of the sense resistor are inputs to a comparator, the output of which controls the first switch. A second current sink, when on, draws current through the second resistor causing the first switch to be held off, turning the charging circuit off. An ON/OFF terminal, to which a variable duty cycle square wave is supplied, controls the turning on and off of the first and second current sinks, with the length of the duty cycle controlling the average current supplied to the battery.

The present invention relates to battery charging in general and more particularly to a low cost highly efficient battery charging circuit particularly useful for mobile computers.
Mobile computers, for example, portable and lap top computers have the capability of operating from a rechargeable battery. This requires that the battery be periodically recharged. Such computers typically have built into them a battery charging circuit for this purpose. Either externally or internally to the computer box, line current is converted to a direct current of the desired value and reduced in voltage. Alternatively voltage from a dc source such a car battery is converted to an appropriate voltage. This voltage is then used through the battery charging circuit to recharge the battery. Typical circuits presently in use are linear circuits which have a relatively low efficiency. Furthermore, these prior art battery charging circuits are relatively costly and have a charging current which is a function of voltage. Thus, there is a need for a low cost, highly efficient battery charging unit.


A system that includes a magnetically actuated motion control device comprising a housing defining a cavity and including a slot therethrough. A movable member is located within the cavity and is movable relative to the housing. A magnetic field generator located on either the housing or the movable member causes the housing to press against the movable member to develop a friction force.

Magnetically actuated motion control devices such as magnetically controlled dampers or struts provide motion control, e.g., damping that is controlled by the magnitude of an applied magnetic field. Much of the work in the area of magnetically controlled dampers has focused on either electrorheological (ER) or magnetorheological (MR) dampers. The principle underlying both of these types of damping devices is that particular fluids change viscosity in proportion to an applied electric or magnetic field. Thus, the damping force achievable with the fluid can be controlled by controlling the applied field. Examples of ER and MR dampers are discussed in U.S. Pat. Nos. 5,018,606 and 5,384,330, respectively.
MR fluids have high yield strengths and viscosities, and therefore are capable of generating greater damping forces than ER fluids. In addition, MR fluids are activated by easily produced magnetic fields with simple low voltage electromagnetic coils. As a result, dampers employing MR fluids have become preferred over ER dampers.
Because ER and MR fluid dampers still involve fluid damping, the dampers must be manufactured with precise valving and seals. In particular, such dampers typically require a dynamic seal and a compliant containment member which are not particularly easy to manufacture and assemble. Further, the fluid type dampers can have significant "off-state" forces which can further complicate manufacture and assembly. Off-state forces refer to those forces at work in the damper when the damper is not energized.
The foregoing illustrates limitations known to exist in present devices and methods. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.

System comprising magnetically actuated motion control device


A fixing apparatus of the present invention for an electronic induction heating system includes a heat roller and a magnetic excitation coil that generates Joule heat within the heat roller. The fixing apparatus includes a coil positioner that positions the magnetic excitation coil around a portion of a periphery of the heat roller, a fixing roller that fixes toner image on a recording medium, and a belt that contacts a portion of a periphery of the heat roller and the fixing roller to conduct the generated heat from the heat roller to the fixing roller. The coil positioner further has a surface of first curvature substantially identical to a curvature of a periphery of the heat roller at an opposition area, the opposition area being opposite to a contact area where the heat roller makes contact with the belt. The coil positioner is spaced from the belt by a predetermined distance. The coil positioner further has a first extension extending from a first end of the opposition area of the coil positioner and a second extension extending from a second end of the opposition area of the coil positioner. The first extension and the second extension are spaced from the belt distances larger than the predetermined distance.

1. Field of the Invention
The present invention relates to a fixing apparatus for an electronic induction heating system and an image forming apparatus equipped with the fixing apparatus, such as a copying machine, facsimile, or printer which utilize an electrophotography device or an electrostatic recording format. The present invention further relates to a wire winding apparatus and a method for producing a magnetic excitation coil that is utilized for an electronic induction heating system, using the wire winding apparatus.
2. Description of Related Art
Generally, fixing devices installed in an image forming apparatus such as a printer or a copying machine are designed to save energy and operate at high speeds. Because of this, devices equipped with an electromagnetic induction heating type heater can be widely utilized in place of halogen lamps and similar devices. Related electromagnetic induction heating type heaters apply a magnetic field, generated by a magnetic excitation coil, to a heating element which then heats the heating element. As an example, this heater can be used as a fixing device that heats non-fixed images formed on a recording medium such as transfer paper or an OHP sheet.
Related heaters equipped with magnetic excitation coils apply a magnetic field, generated by the magnetic excitation coil, to a cylindrical heat generation roller which in turn generates an eddy current in an electroconductive layer formed by the surface layer of the heat generation roller. The electroconductive layer is then heated by the Joule heat generated by this eddy current. Normally, it is effective to design the shape of the magnetic excitation coil along the outside shape of the cylindrical heat generation roller. Fixing devices which are equipped with heat-resistant endless belts suspended between a fixing roller, a heat generation roller, and both rollers are well known. It is also preferable to closely place a magnetic excitation coil along the heat generation roller and endless belt in a fixing device equipped with this type of endless belt.
In order to stably maintain an approximate cylindrical shape when forming a magnetic excitation coil into an approximate cylindrical shape, from the past, the magnetic excitation coil was changed into the desired shape (semicircular shape) along with a coil shape retaining member (as an example refer to related art 1). Further, when forming the magnetic excitation coil into an approximate cylindrical shape, there is a chance that the temperature distribution of the heating element may not be uniform. In order to make the temperature distribution of the heating element uniform, it has been proposed to partially change the distance between the magnetic excitation coil and the heating element to partially alter the magnetic excitation coil making it more distant from the heating element (as an example refer to related art 2).
[Related Art 1] Japanese Patent Publication 2000-243545 [Related Art 2] Japanese Patent Publication H9-26719
If the diameter of the heat generation roller is made smaller than the fixing roller in a fixing device in which an endless heat-resistant belt is suspended between the fixing roller and the heat generation roller, the endless heat-resistant belt will be expanded into a fan shape towards the fixing roller. In addition, there is a chance that the heat-resistant belt might bulge close to the contact area between the heat generation roller following the rotation of the belt.
Even if the magnetic excitation coil formed in an approximate semicircular shape matching the curvature of the heat generation roller is placed close to the heat generation roller, a problem occurs wherein the edge of the open side of the magnetic excitation coil interferes with the heat-resistant belt that is expanded into a fan shape or the heat-resistant belt that is bulging. In order to avoid interference between the magnetic excitation coil and the heat-resistant belt, the installation range of the magnetic excitation coil can be restricted to contact area L between the heat generation roller and the heat-resistant belt although this does not act in response to the requirement to provide efficient heating up to a range wider than contact area L by closely placing the magnetic excitation coil. Separating the distance between the heat-resistant belt and the magnetic excitation coil enough that they do not interfere with each other in order to avoid interference between the magnetic excitation coil and the heat-resistant belt even further results in a problem of a worsening magnetic bonding between the magnetic excitation coil and the heat generation roller and heat generation loss.
In related art 1, after securing a planar coil shape retaining member on a planar coil winding jig and winding the coil wire on the planar surface of the above-mentioned coil shape retaining member, the coil is pressurized. Then, a substantially planar-shaped coil is heated until reaching a softening temperature together with the coil shape retaining member and changed into a shape that forms the surface of the coil.
When changing the pressurized planar-shaped coil as required together with the coil shape retaining member, the outside applies stress in a direction that compresses the inside towards a direction that stretches the copper wire towards the bending direction of the magnetic excitation coil copper wire wound in a substantially planar shape. As a result, a problem of stress being applied to the insulation cover of the copper wire and the insulation cover deteriorating occurred. In particular, the magnetic excitation coil copper wire used in an induction heater had a remarkable problem because Litz wire was used for this copper wire and this Litz wire used a very thin cooper wire wound several tens of times.
As disclosed in related art 2, if the bending amount of the magnetic excitation coil is utilized to make the heat generation distribution uniform, there as also a problem of more stress being applied to the coil and the stress applied to the insulation cover of the copper wire increasing even more.

Wire winding apparatus and method for producing magnetic excitation coil