Abstract: Electrical distribution apparatus, such as a pad-mounted electrical distribution transformer, including an electrically grounded tank, an electrical element in the tank, and a draw-out surge arrester assembly which extends into the tank. The draw-out surge arrester assembly includes a housing, and a draw-out device removably disposed in the housing. The draw-out device includes a fuse connected in series with the surge arrester, between the electrical element and grounded tank, with the fuse being sized to isolate the surge arrester from the electrical element, should the surge arrester fail to recover properly from a voltage surge.

Abstract: A high-voltage system surge eliminator for the protection of electric transmission and distribution stations against line and switching transients, atmospheric discharges and other adverse effects including such as those caused by lightning. The eliminator is suitable for the protection of substations and of individual equipment units, selectively, and is applicable to both direct current and alternating current single and multi-phase systems, selectively. Two basic and typical eliminator varieties are shown and described.

Abstract: A process instrument enclosed in a hermetically sealed housing for indicating and controlling a measured variable, such as the level in a tank. The instrument includes magnetically operated electrical switches actuable between open and closed positions in response to the measured variable. The electrical switches used are capable of switching current levels on the order of 10 Amps.

Abstract: An electrically insulating substrate has an array of holes formed in it for accepting electrically conducting support pins, each pin having a light-emitting element mounted on the upper pin end. Each upper pin end is surrounded by an insulating ring and a conducting ring, the light emitting element being connected electrically between the conducting pin and the conducting ring. Electrical connections are made via a printed wiring pattern on each surface of the substrate. Optical collimating elements are formed in a wafer having openings that surround each of the conducting rings with a small clearance, the wafer engaging and being insulated from the substrate with the printed wiring.

Abstract: A protector module (30) for protecting the conductors of a telephone loop cludes a pair of protector assemblies (40-40') which are supported within a common housing (32). A gas tube voltage protection subassembly (42) of each protector assembly is connected electrically to a grounding subassembly (44) for causing current associated with excessive voltage surges to be conducted to ground. A first electrode includes a portion which extends through annular dielectric and metallic members and an opening of an open-ended metallic container (93) to engage a shunting element (62) of a current protection subassembly (41). The superimposed annular members are held in engagement with the first electrode at a substantially constant pressure by axial forces applied by turned-in portions (109--109) of a side wall of the metallic container. The shunting element is supported at one end of the line pin in an initial position by a fusible material.

Abstract: A power semiconductor column has power semiconductor elements arranged in alternation with thermally and electrically conductive evaporation blocks. Each evaporation block is connected in a separate heat-dissipating fluid circuit. Each fluid circuit has a heat exchanger connected to the corresponding evaporation block by way of a pair of flexible, electrically insulating fluid connections. Heat-carrying dielectric fluid circulates within each circuit between the evaporation block and the heat exchanger, cooling of the semiconductor elements being effected by evaporation of the fluid in the evaporation block and condensation of the fluid in the heat exchanger.

Abstract: A light responsive control and overload protection circuit for low voltage illumination systems includes means responsive to ambient light for providing an enabling output. Control means respond to the enabling output for switching heating current on when enabled. Heat-producing means is provided. The heating current passes through the heat-producing means whenever the control means is enabled. Heat-responsive circuit breaker means are in circuit between a low voltage power source and the load. The heat-producing means is thermally coupled to the heat-responsive circuit breaker means to transfer heat thereto and effect and maintain an opening thereof whenever sufficient ambient light is present. Heat-responsive means respond to heat from the heat-producing means to prevent the overheating thereof during overloads and load circuit short circuiting.

Abstract: A solid state semiconductor pressure sensor is described in which the pressure sensor element is protected from the ambient whose pressure is being measured by a combination of a pressure transfer medium and a thin covering membrane. A method is described for applying the thin covering membrane so as to substantially avoid entrapment of air or formation of voids in the pressure transfer medium which would degrade the performance of the sensor. The pressure transfer medium is a gel-like material such as a silicone rubber. The membrane is chosen to be substantially impermeable to the ambients being measured and sufficiently flexible to avoid attenuation of the input pressure signal. The membrane is cast in place by applying a thin liquid coating or a heat deformable film over the pressure transfer medium and then converting it into a thin solid membrane stuck to the pressure transfer medium and the pressure sensor body.

Abstract: A low voltage buried wire isolator for interrupting the metallic path between the common grounding system in a structure and the positive grounding system of the telephone or television cable grounding systems. The isolator comprises a housing having an electrically conductive clamping assembly clamped to the metal ground sheath of the service cable. A high voltage protector such as a gas tube is electrically connected, at one of its ends, to the clamping assembly and is designed to normally prevent the flow of electrical current therethrough which is below a predetermined value. A metal fitting is connected to the other end of the high voltage protector and is operatively electrically connected to at least a pair of signal circuit protectors also mounted within the housing. If a power crossover should occur, the high voltage protector prevents the metal ground sheath from overheating since it is electrically insulated from the cable protective apparatus.

Abstract: An integrated circuit package in which semiconductor elements mounted on an insulating substrate, ends of lead pieces introduced from the outside and wires that electrically connect them, are accommodated in a cell that is air-tightly defined by the substrate, a cap and a sealing glass. The lead pieces are composed of an alloy having a coefficient of thermal expansion nearly equal to, or smaller than, the coefficient of thermal expansion of the substrate. The alloy is an iron alloy which contains nickel and cobalt, and having a martensite transformation temperture of lower than -55.degree. C.

Abstract: A device is provided for the temperature measurement and thermal protection of an object and more particularly of an electronic "solid state" circuit, using an analog network representative of a thermal model of the circuit to be protected. It comprises, on the one hand, an initialization device for, at the time of switching on, positioning the state of the thermal model at an operating point representative of the real temperature of the object to be protected and, on the other hand, elements isolating the analog network thus allowing it to be representative of the real thermal state of the circuit to be protected, whatever the state of the circuits internal to said device. The device is appropriate for thermal protection of an electronic power controller.

Abstract: A semiconductor power module includes a metallized ceramic carrier plate having an opening formed therein, a semiconductor power component with a base area of a given size adjacent the ceramic plate at the opening, a heat pipe integrated in the semiconductor power module having a vapor space, a condensation zone and a heating zone for distributing heat removed from the semiconductor power component at the heating zone over an area of the condensation zone being larger than the given area, a highly heat-conducting ceramic base plate having two metallized sides, and a frame vacuum-tightly interconnecting the carrier plate and the base plate forming the vapor space of the heat pipe therebetween.

Abstract: A control circuit for shutting down a constant-current supply suitable for a double-end feeding power supply system for a long-haul wire telecommunication system. The shutdown control circuit includes a voltage detecting circuit, a current detecting circuit and an AND gate. The voltage and current detecting circuits provide detection signals when the constant-current supply provides an output voltage greater than a predetermined voltage value and the current at the output terminal is less than a predetermined current value. The predetermined voltage and current values are determined to correspond to a load circuit input resistance at which the supply of a current by the constant-current supply is to be shut down.

Abstract: A voltage regulator includes an output power element and protection circuit connected to a control terminal of the power element in such a way as to cause the element to conduct in a direction opposite to that of normal operation, when the transient overvoltages of polarity opposite to that of the generator reach a predetermined value. The energy associated with the transient is thus discharged via the output power device and it is not therefore necessary to use additional power components to carry out this function, leading to reductions in size and production costs.

Abstract: A load-dependent current limiter for the power supply of a multi-module electronic system has a programming resistor in each module connected between the power supply voltage and a reference bus. The current through each programming resistor is proportional to the current requirements of the module. The voltage of the reference bus, which is proportional to the total current through all the programming resistors, is compared to the voltage developed across a sensing resistor by the total power supply current. When the sense voltage exceeds the reference voltage, indicative of tapping excess power, a signal is sent from the comparator to shutdown the power supply.

Abstract: The invention concerns a primary switched-mode power supply device with several electrically isolated secondary circuits, the output voltage of the secondary circuit being connected to an actual-value sensor with a regulator connected to the sensor output, with the output voltage being protected by a fuse connected in series with the filter capacitor. In accordance with the invention, the junction point of the filter capacitor and the fuse is connectable by an electrically controlled switch to the output terminal of the actual-value sensor as soon as the switch is turned on after the fuse has been tripped. Thus, a simple embodiment of an over-voltage protection is obtained for a primary switched-mode power supply unit with several electrically isolated secondary circuits, without additional monitoring of an in-phase output voltages A.sub.2 and A.sub.3 and a controlled secondary circuit being controlled in case of a fault to an output voltage that is lower than the normal operating controlled output voltage A.

Abstract: A cover for a semiconductor package includes a composite layer on its upper most surface containing a passive circuit. The passive circuit may include a number of passive components to fulfill various functions such as capacitive coupling and decoupling, resistive pull-up and pull-down, et al. Appropriate terminal points of the passive circuit terminate in contacts which are disposed on the top surface of the composite layer. Terminals are attached to the contacts for interconnecting the passive circuit with terminal leads of the semiconductor package or other circuit components.

Abstract: A two-terminal A.C. device is described which can be series connected with a lighting fixture to prevent overheating of the fixture in an overload condition, namely, when a lighting element exceeding the power rating of the fixture is installed. In broad terms, the device includes a bidirectional, self-extinguishing switch which can be triggered to conduct current between the two terminals of the device, and control circuitry operable from the voltage difference and current between the two terminals occurring in use to regulate the triggering of the switch. The control circuitry includes triggering circuitry which generates triggering signals from the voltage difference across the terminals of the device and normally applies the triggering signals to the control terminal to permit a predetermined measure of conduction.

Abstract: A motor protector having a thermostat metal element thermally coupled to an electrical motor in a refrigerator compressor motor system has a heater responsive to motor current thermally coupled to the thermostat metal element and has an improved component arrangement to provide locked rotor and ultimate trip protection for the motor without requiring calibration of the operating temperature for the protector after assembly or after incorporation in the motor system.

Abstract: In a radiant heating unit, an insulating support for carrying a radiant heating resistor is molded or pressed using a granulation of expanded clay materials, particularly expanded mica or vermiculite. The granulation is compressed and bound in a blank by a mineral binder, particularly water glass, and the heating resistor is positively secured in the moulded granulation by embedding parts of the resistance wire forming the resistor, in such a way that the resistor is in part free of the insulating support on the front. The heating resistor can be embedded during production of the insulating support or can subsequently be pressed into the support. The insulating support of the heating unit is low in weight and easy to manufacture, has optimum electrical and thermal insulating properties and has very good strength, whereby the heating unit has a long service life.