Abstract: A battery charging circuit comprising means to supply a DC output from the mains supply for inter alia recharging a rechargeable battery, switch means in series with the battery across the DC output which are normally closed but which open from time to time to disconnect the battery from the DC output, battery voltage monitoring means for measuring the potential or emf of the battery at the time when the switch means are open, and means for determining a maximum potential and therefore fully charged state for the battery and decreasing the charging current from the DC output to the battery when a fully charged state is determined.

Abstract: An internal combustion engine provides the motive power source to various types of aircraft using a ducted fan. The engine has a rotating annular cylinder which is rotated in a predetermined ratio to oscillation of a plurality of pairs of oscillating pistons in the cylinder, the pistons being so oscillated so that adjacent pistons are moved alternately apart from one another and toward one another for the respective strokes of the internal combustion engine and having intake ports, exhaust ports and ignition means on the rotating annular cylinder located by the rotation of the cylinder between adjacent pistons according to the firing order and cycle of the engine. The engine includes the use of unitary in place of articulated, oscillating crank arms to transmit power from the torque tubes to the crankshaft, the use of pistons have gabled surfaces that are rigidly connected to the torque discs, and fan blades attached to the rotating annular cylinder providing the air thrust for propelling the aircraft.

Abstract: A fin assembly includes a fin, a pair of mounting pieces for removably mounting the fin to an integrated circuit. The fin includes a bottom surface for contacting an upper surface of the integrated circuit and an upper surface from which a plurality of ridges extend. An extension extends downward from each side of the bottom surface, such that the distance between the two extensions is equal to the width of the integrated circuit. On at least one of the mutually facing walls of each outermost ridge and its corresponding adjacent ridge, a groove extends along the length of each ridge. Each mounting piece includes a base and two beveled sides each extending downward to form a distal snapping end. A pair of pins extend upward from a top of the base, such that a fan may be mounted by passing the pins through pin holes in the corners of the fan.

Abstract: A venturi scrubbing system optimized for removing the most optically active sized particles from a gaseous effluent stream is disclosed. Before entering the venturi the effluent stream is subcooled to cause condensation of water vapor and other condensibles, thereby greatly reducing the volume of the effluent stream. In the venturi stage a scrubbing liquid is added in the form of droplets having a median diameter which is optimized to remove the optically active particles. Preferably, the median diameter of the scrubbing liquid droplets is between 10 and 200 microns. A two-fluid nozzle may be used to efficiently form the droplets. After passing through the scrubbing stage, which may also comprise one or more impingement plates, the cleansed effluent may be passed through an afterburner to remove combustible materials such as organic vapors.

Abstract: An improved audio compressor of the type which is useful in a hearing aid and having a programmable compression ratio is disclosed. In the preferred embodiment, the compressor is used in a hearing aid device of the type which comprises a bandsplit filter to divide an input audio signal into a plurality of frequency bands. Associated with each frequency band is a limiter means which provides variable gain amplification of the input signal as a function of the amplitude of the input signal and as a further function of a programmable control signal. A feedforward means is disposed in parallel to the limiter means, said feedforward means providing a fixed gain signal. The output of the limiter means and the feedforward means are combined at a summing node which forms the input to a variable gain amplifier. Associated control circuitry allows the limiter gain to be programmed to meet the needs of an individual user. The compressor has a variable compression ratio in the form of a sigmoid function.

Abstract: A composite litter board is made from two separate rigid board members that are adapted to be releasably secured to each other by two rigid partial sleeves with C-shaped cross sections that have narrow openings.

Abstract: The present invention comprises a hearing system apparatus and method for electromagnetically communicating signals to a magnetic transducer. The apparatus includes a signalling circuit for producing a pulse-width modulated current signal. An antenna means is coupled to the signalling circuit for producing a variable electromagnetic field whose energy intensity is modulated by the output of the signalling circuit. In addition, an energy storage circuit is coupled to the antenna for storing a substantial portion of the energy stored in the magnetic field produced by the antenna when the magnetic field collapses between cycles of the current signal. Also, an energy recycling circuit is coupled to the storage circuit and the antenna for recovering the energy stored in the storage circuit for use in the next electromagnetic field cycle.

Abstract: A ductile brazing material containing gold, nickel, vanadium and, optionally chromium or molybdenum is disclosed for directly bonding ceramic to ceramic or ceramic to metal over an optimum temperature range.

Abstract: An improved motion picture coding scheme is described which provides the benefits of both sub-band coding and motion compensation thereby providing greater degrees of compression than would be obtained using either of these techniques separately. The system generates high and low frequency frames from each pair of frames in the original motion picture. The high frequency represents the difference between the first and second frames of the motion picture. The pixels of the low frequency frame are either the average of two corresponding pixels, one from each of the original frames, or a value derived from a single pixel in the first frame. In the later case, the derived value is chosen to minimize artifacts that could hamper further compression of the low-frequency frame based on sub-band coding.

Abstract: A three-terminal serial-communication peripheral device for low-cost applications is described. The peripheral device comprises a first terminal for receiving a modulated power signal including a source of power and a clocking signal, a second terminal for receiving a reference potential such as a ground reference, and a third terminal for communicating data to and from the peripheral device. The peripheral device further comprises a digital subsystem which exchanges data with an application system. The exchanged data may be stored and retrieved by the digital subsystem, as when the subsystem is a memory unit, or the data may be in the form of measurement data which the peripheral device is supplying to the application system, the measured data being supplied by a sensor of the subsystem. With its three terminals, the peripheral device can communicate data to and from the application system.

Abstract: The coated substrate product finds particular application in eyeglass and sunglass lenses, architectural glass, analytical instrument windows, automotive windshields and laser bar code scanners for use in retail stores and supermarkets. The product has greatly improved wear resistance for severe abrasive environments and comprises a substantially optically transparent substrate, a chemicaly vapor deposited first interlayer bonded to the substrate and a chemically vapor deposited outer layer of substantially optically transparent diamond-like carbon bonded to the interlayer and away from the substrate.

Abstract: A system and a process is disclosed for purifying water with a domestic water holding tank and ozone-air mixture from an ozone generator. A mixer injector connected to a pump which provides the means for entraining the ozone-air stream gas into the water stream is positioned both vertically within the tank and laterally to assure the most efficient purification of the holding tank water.

Abstract: A novel gamma retinoic acid receptor is disclosed. The novel receptor is encoded for by cDNA carried on plasmid pGEM-hRAR.gamma., which has been deposited with the American Type Culture Collection for patent purposes. Chimeric receptor proteins are also disclosed. The chimera contain at least one functional domain from the new gamma retinoic acid receptor.

Abstract: A contact transducer assembly for an electromagnetically driven hearing device such as a hearing aid or other audio signal reproducing device worn by a user is described. The contact transducer assembly includes a transducer which is attached to a biocompatible support. This assembly is supported on the tympanic membrane of the wearer by surface adhesion, such that it can be readily inserted and removed in a manner similar to that of a conventional contact lens worn on the eye.

Abstract: Apparatus for splicing the leading portion of web material from a fresh supply roll to the trailing portion of web material from an expiring supply roll to a take-up system comprising a pair of guiderollers normally positioned apart from each other, apparatus for gripping the leading portion of the fresh web so that the leading portion can be held in contact with one of the guiderollers, apparatus for pressing the two guiderollers together so that the leading portion of web material from the first supply roll can be joined by an adhesive to the trailing portion of the web material moving from the expiring supply roll, apparatus for cutting the web material moving from the expiring supplying roll moveable between alternate cutting positions downstream from the guiderollers and apparatus mechanically linked to, operative to actuate the respective functions of, the apparatus for gripping the leading portion of the fresh web, apparatus for pressing the guiderollers together and the apparatus for cutting the web m

Abstract: The present invention relates to the protection of a semiconductor active device from thermal breakdown without actually measuring the temperature of the semiconductor active device. Instead, the present invention measures the magnitude of the forward electrical signal generated by the active device and the reflected electrical signal resulting from the interaction of the forward electrical signal and a load. The thermal energy generated by the active device is a function of these electrical signals. The generated thermal energy is transferred out of the active device at a predetermined rate. The temperature of the active device is calculated as a function of the thermal energy generated by the active device and the amount of thermal energy transferred out of the active device. When the calculated temperature is above a predetermined value, the active device is shut off, thereby preventing further generation of thermal energy.

Abstract: A method for generating platinum features on the surface of a substrate is disclosed. The method provides an inexpensive means for constructing small platinum features. The method utilizes a photoresist mask to define the platinum features. The problems associated with residue from the deposition of the photoresist mask are overcome by utilizing an etching step which removes any such residue. The etching step also allows the platinum features to be recessed into the substrate surface.

Abstract: A cellular telephone system is described of the type wherein a plurality of contiguous cells, each having a different assigned set of transmission frequency channels, are arranged with handoff control for maintaining continuous communication with mobile telephones moving from cell to cell. The system allows multiple access by including assigning at least one of the frequencies in the assigned set of transmission frequencies to more than one mobile telephone. Three embodiments of the multiple access systems are disclosed. In one embodiment, a frequency division multiple access is used. In a second embodiment, a time division multiple access is used. In a third embodiment, a code division multiple access is used.

Abstract: A start circuit for starting the generation of pulse width modulated switching pulses is disclosed for use in a DC/DC switching converter power supply. The starting circuit is responsive to the initiation of a DC voltage source and starts the operation of a pulse generator. The starting circuit also includes a relaxation oscillator connected to the DC voltage source for periodically generating a start pulse at a predetermined frequency. Ongoing power is coupled to the pulse generator once the generator begins operation. The relaxation oscillator is selectively disabled when the pulse generator is powered by the ongoing power supplied by the power supply during normal operation. The start circuit further includes a delay function for delaying the disabling of the relaxation oscillator for a preselected period after shutdown of the power supply and includes a rapid start function for reducing the time between restoration of input power and the operation of the start circuit.