Abstract: A personal branch exchange telephone system including improved interface circuitry to couple the system to outside telephone lines as well as to individual telephone sets on extension lines in the PBX system. The PBX system is connected to the telephone lines only through electromagnetic coupling and circuitry is provided to detect both ringing signals and loop current carried by the telephone lines.

Abstract: A short arc type lamp having a concave reflecting wall including a convex space formed behind the concave wall such that the reflecting wall is relatively thin near the focal point of the lamp and relatively thicker radially outward. A copper sleeve member is attached to the reflecting wall within the convex space to conduct heat from the reflecting wall to the exterior wall of the lamp.

Abstract: The present invention includes an apparatus and a method for connecting at least a pair of stages in DC series between a pair of power-supply potentials so as to provide economical utilization of the power supply. The stages are connected so as to maintain their AC independence.

Abstract: A lubrication system for internal-combustion engines having a mechanical-type oil pump and turbocharger. The system includes an auxiliary electrically operated oil pump, a first time-delay relay connected to the ignition system to energize the electrically operated oil pump for a first time period after the ignition is turned on to prelubricate the engine, and a second time-delay relay to energize the electrically operated pump for a second period after the ignition is turned off to lubricate the turbocharger.

Abstract: A self-calibrating temperature sensing probe having a temperature sensor positioned adjacent to a vial of a predetermined substance in an isothermal environment created by a housing and insulation. A heating element is positioned about the vial to effect vial heating. The substance is preselected for its melting point temperature, which is in excess of the ambient temperature of the environment surrounding the housing. During recalibration the substance is heated above its melting point and allowed to cool. During cooling the temperature of the substance is recorded and the liquid-to-solid phase change determined. Recalibration is affected using the phase change temperature of the substance as a calibration point.

Abstract: A device for use with executive and secretarial telephone units associated in a work group, having a programmable microprocessor which selectively controls the connection of incoming telephone lines to the secretarial telephone units and monitors the status of the telephone lines and provides such information to the secretarial telephone units.

Abstract: A high-speed feedback circuit for use with, particularly, a buck or buck derived regulator (power processor). The circuit employs a voltage developed by the regulator after the switch and before the filter. From this voltage, a current is developed which is combined with (subtracted from) a reference current. The combined current is integrated in a capacitor to develop a voltage used to drive the switch. The load is not referenced to ground.

Abstract: A bottle closure device having a stem member with an enlarged top portion, a collar resiliently biased away from the top portion, a retainer member on the end of the stem, and an O-ring between the retainer member and the collar. When the end of the stem is placed within the mouth of a bottle, the biasing means acts to cause the retainer member to press the O-ring radially outward against the collar to form a fluid-tight seal with the mouth of the bottle.

Abstract: A method for producing highly detailed and multi-relief nameplates. A master image is produced by photoetching with a photopolymer. A negative production tool is formed from this master image, and comprises a plurality of individual nameplates formed in a sheet. The sheet is plated with a thin layer of nickel, and backfilled with a mixture of nylon and an epoxy resin, which is then cured to produce a solid mass. The obverses of the nameplates are chrome-plated and may be painted as desired. The reverse of the sheet is subjected to a cutting step using a fly cutting mill which separates the sheet by horizontally cutting raised edges between adjoining nameplates to produce a plurality of individual nameplates.

Abstract: A switch having gold-plated contacts on which is formed a gold-mercury amalgam, at least the contacts being immersed in a totally fluorinated hydrocarbon fluid.

Abstract: An optical positional sensing apparatus for providing precise position and approach angle of a mobile assembly with respect to a fixed assembly. The apparatus includes a light source and optics to produce a rotating horizontal beam. Optics and a transducer are included which can detect the light beam when reflected back on itself. A corner reflector is affixed to a piece of equipment to which the mobile assembly will travel. The beam is rotated by means of a drive motor. Light hitting the corner reflector is reflected directly back under three circumstances, i.e. when the beam strikes either corner or when the beam is perpendicular to the reflector. A rotary encoder is coupled to the drive mechanism and supplies continuous angular positional data to a microprocessor. The transducer is also coupled to the microprocessor which generates data sets of angular location for each transducer signal. Simple trigonometric calculations provide the desired position and approach angle data.

Abstract: A method and an apparatus for texture generation for a digital image generator of an aircraft flight simulator is disclosed in which (a selected two of the three) coordinates of each pixel of an image are inverse transformed to earth coordinates (112-124, in FIG. 11) from which addresses are developed (126, 128 and 130) for accessing a texture table (132 and 134) to retrieve elements from which an appropriate pixel intensity is developed (140). The table stores near (132) and far (134) texture, the far texture elements being interpolated to avoid a checkerboard effect, stores a limited number of texture types, the elements of selected texture types being combined (132 and 134) to develop additional texture types, and stores levels of detail (degrees of filtering) the appropriate levels being accessed (126) to avoid aliasing (scintillation of a scene), adjacent levels being mixed (136 and 138) to provide smooth detail level transition.

Abstract: A system for dispensing liquid chemicals, such as photoresist, from containers which includes a valve to govern the flow from the containers, a reservoir to intermediately hold the chemicals prior to pumping, and a level detector to monitor the liquid in the reservoir and to control the valve, and an aspirator to remove air from the reservoir. The aspirator is activated in response to signals from the level detector indicating that the reservoir level is low. The increased suction causes liquid to be drawn from the container into the reservoir. If after a period of time the level detector indicates the reservoir level is still low, the valve will cause liquid to be drawn from a different container. The aspirator is deactivated a period of time after the level detector indicates that the reservoir level is normal.

Abstract: A system and method for controlling the operation of a dc stepping motor utilized for positioning a read/write head on a magnetic data storage disk operates to selectively establish different magnetic field strengths on the core members of the stepping motor, thereby minimizing the time period required to stop the motor at precise, preselected positions.

Abstract: A non-linear network is disclosed for use in a power processor (converter) for limiting transformer primary winding current during (switching) transitions of a transformer driving potential, the network employing a resistor for coupling a suitably limited current from the potential to the winding and a saturable reactor connected in parallel with the resistor, the reactor for bypassing the resistor except during (and until a suitable period after) transitions of the potential level.

Abstract: An electronic proximity identification and recognition system. The identification and recognition sections are physically separate from one another, but inductively coupled to one another by two-way coupling. The identification section and recognition section each have a sending and a receiving antenna. The antennas in each section are structured to have virtually zero mutual inductance.

Abstract: An improved short-arc gas discharge lamp having a solid ceramic body with an integral reflector surface. The lamp includes a sapphire window, fitted to one end of the ceramic body, and a thermally and electrically conductive base fitted to the opposite end of the ceramic cylinder to form a sealed pressure chamber. The window is secured to a unitary U-shaped flange for improved strength and leak resistance. A pair of annular back-up rings secure the window flange to the ceramic body so as to relieve stress on the window flange. The reflective surface is formed by pressing the ceramic body, when hot, with an unpolished mandrel, for greater accuracy in surface configuration. A smooth, highly reflective surface is obtained by subsequent surface treatment.

Abstract: A process for assuring that the individual computational elements of a fault-tolerant computer system have the same view of the external world when applied in applications where input data representations of the same quantity may have slight variations without being incorrect. The process transmits data between each of the computational elements through circuitry utilizing transmitters and receivers, and provides a check as to the accuracy of each such transmission, resulting in each computational element either having the same plurality of data as each other computational element, or a representation that a transmission was faulty.

Abstract: An improved rectifying network employing a semiconductor diode, a saturable reactor connected in series with the diode between a pair of terminals, and means for biasing the saturable reactor to saturate the saturable reactor core for forward diode current flow.