Abstract: Glow plug with a glow tube into which an inner pole projects and which is connected via heating and control spirals to the glow tube, the control spirals being located with respect to the heating spirals such that they are uniformly heated over a major portion of their length by the heat from the heating spirals.

Abstract: Glow plug with a glow tube into which an inner pole projects and which is connected via heating and control spirals to the glow tube, the control spirals being located with respect to the heating spirals such that they are uniformly heated over a major portion of their length by the heat from the heating spirals.

Abstract: A metallic access test extension system architecture for a digital transmission system is provided. The digital transmission system includes a local end and a plurality of remote ends, each of said plurality of remote ends including a digital communication path and a metallic test pair connection. The local end includes a corresponding digital communication path and corresponding metallic pair connection. The architecture includes a remote unit coupled to each metallic test pair and digital communication path at each of said plurality of remote ends. The remote unit includes a metallic access test extension module. The architecture further includes a central office unit at the local end of the digital communication path, the local end unit including a metallic test extension module and a switch system, responsive to a control signal, for selectively connecting the digital communication paths and metallic test pairs at the local and to the metallic test extension module in the local end unit.

Abstract: The present invention is directed to delta modulation in which the modulation level is optimized to improve overall system performance. A delta modulator in accordance with the invention includes a step size controller having a overload detector, a step size generator and a modulation level regulator. The overload detector monitors the output serial bit stream and produces a signal indicative of whether overload conditions are present. The step size generator produces steps of varying sizes in response to an input signal. The modulation level regulator monitors the signal output from the overload detector and outputs a modulated signal when the overload detector output has reached at least a certain threshold level. The modulation level regulator output is received at the step size generator input.

Abstract: A glow plug having an interior pole and a glow tube with a tip portion, a heating element located in the tip portion, and a regulating element, formed of an electrically conductive material having positive temperature-resistance coefficients, arranged in the glow tube. The interior pole of the glow plug is serially connected with the regulating element, the regulating element is serially connected to the heating element, and the heating element is serially connected with the glow tube tip in a construction for minimizing heat transfer between the regulating element and the interior pole.

Abstract: A gas concentration and/or bulk flow rate sensor suitable for measuring the oxygen concentration and the bulk flow rate of gas delivered to a patient for medical purposes. Two piezoelectric transducers mounted on a printed circuit board are interconnected by an elongated coiled tube. The gas is flowed around one of the transducers, through the tube and around the other transducer. Periodically, one of the transducers is energized with a single short duration pulse to transmit a sonic wave through the gas to the other transducer. The travel time for the sonic wave is measured. The two transducers are alternately used as transmitters and receivers so that the wave travel time is measured both with and against the gas flow direction. A thermistor is located in the center of the coiled tube for measuring the temperature of the gas. From the measured times, the measured temperature and stored formulas, a microprocessor calculates the oxygen concentration and/or the bulk flow rate for the gas.

Abstract: A sheathed-element glow plug has a front resistance heating filament connected in series with a rear resistance regulating filament having a higher positive temperature coefficient (PTC) than the front filament. The rear filament is made of cobalt/iron alloy consisting of 44-80% by weight cobalt, 20-35% by weight iron, up to 1% miscellaneous components and nickel, if present, in an amount of 0 to less than 15% by weight. The alloy has a resistance ratio (20.degree.-1000.degree. C.) which is no more than approximately 7.5 in the range from about 100.degree. C. to between about 400.degree. C. to about 600.degree. C., and which ratio rises sharply to values from 7.5 to greater thin 12 in the range from 400.degree. C. to 600.degree. C. to about 900.degree. C.

Abstract: A glow plug for an air compressing internal combustion engine of the type having a tube which is closed at one end and connected to a plug housing on an opposite end with a wire filemant-like resistance element disposed in an insulating material within the tube and formed two series-connected resistance filaments, of which the rear resistance filament, serves as a regulating filament, having a higher positive temperature resistance coefficient than the front resistance filament, which serves as a heating filament, is improved so as to enable the heating up time to be reduced without adversely impacting upon the effective life of the glow plug. In accordance with various embodiments, this result is achieved through the use of, for example, special alloys for the material of the regulating filament which have a resitance at 1000.degree. C. that is greater than their resistance at 20.degree. C. by a resistance ratio over about 7.5:1, and preferably greater than 12:1, and in particular, about 14:1.

Abstract: A self-regulating electric glow plug for an air-compressing internal combustion engine includes an elongated tube having a first end arranged within a plug housing and a second closed end defining a tubular component adapted to extend into a combustion chamber of the engine to produce heat when heated to a glowing condition. A coiled electric resistance heating element is disposed entirely within the tubular component and is embedded in a mass of thermally conductive electrical filling the tube. The resistance element includes two oppositely wound resistance wire coils connected in an end-to-end serially connected array with the first coil being located closest to the glow plug housing and the second coil being located closest to the closed tube end. The first coil has a higher positive temperature coefficient of resistance than the second coil.

Abstract: A glow plug for internal combustion engines, the plug including a plug barrel, an electric heater for igniting the fuel, and a device for the metered injection of liquid fuel into the glow plug. The plug includes a centrally positioned heating pin in a pasageway through which the metered fuel passes, the heating pin including a thickened portion to define a valve. A chamber is provided in the glow plug barrel and is heated by the electric heater for evaporating the injected liquid fuel. The barrel includes a tube around the heating pin tip to provide a mixing chamber that contains concentrically arranged bores that extend into the mixing chamber and are connected to an air supply line in the vicinity of the opposite end of the plug barrel to permit air and evaporated fuel to mix to give improved combustion.

Abstract: The invention concerns a floppy disc drive unit in which all the movements are made automatically with the aid of two motors. Using a positioning motor positioning a magnetic head on various tracks of the floppy disc, the floppy disc is automatically drawn into the floppy disc drive unit and ejected therefrom. With the aid of a driving motor provided to drive the floppy disc, the floppy disc is clamped and unclamped and felt pressure pads are lowered and raised automatically.

Abstract: The invention relates to an arrangement for automatically loading a floppy disc into a floppy disc drive unit, using a positioning motor that locates a magnetic head on various tracks on the floppy disc. After the floppy disc has been partly inserted in the floppy disc drive unit, the floppy disc is grasped by a gripping element disposed on a slide. The positioning motor moves the slide at the same time as the magnetic head so that the floppy disc is drawn into the floppy disc drive unit. Then the slide is locked. To eject the floppy disc, the lock is released and, guided by the positioning motor, the slide, together with the floppy disc, is partially ejected from the floppy disc drive unit.

Abstract: An arrangement for processing and modifying copy material for remote-controlled typewriters, in which a box-shaped frame holds the electronic circuit boards. The frame is provided with guides into which the circuit boards are inserted in a manner whereby the guides are open on both sides and to the rear. When inserted into the guides the circuit boards are located one above the other. The rear wall of the frame is rotatable upwards and has a window spanning substantially all of the circuit boards. A blower is connected externally to the window on the rear wall, and another window is provided in the region of the corner of the frame lying diagonally opposite the window on the rear wall. Both windows are of substantially the same height.