Abstract: An apparatus for use in thermally testing electrical components, especially microelectronic components, such as dual in-line integrated circuit packages is disclosed. The apparatus is for use in testing the electrical performance of components when subjected to elevated temperature. Heat is applied through resistive heating elements disposed adjacent the electrical components which are mounted in electrical connectors, such as DIP sockets. Separate test and heater printed circuit boards attachable to conventional edge connectors can be employed. Insulation completely surrounds the sockets and the electrical components. Heating elements having a ferromagnetic-nonferromagnetic layer construction and exhibiting constant temperature regulation at a characteristic Curie point can be employed.

Abstract: Operating temperature of a liquid crystal cell is controlled by passing heated air on its surface, the heater for the air being operated according to the average temperature of the cell measured by a sensor. Fine control is effected by means of resistive heaters affixed on the exterior surface and by electrodes provided at strategic locations inside to pass current through a conductive layer.

Abstract: A circuit package, or other device, (10) is mounted on a printed circuit board, or other substrate, (14) with an electrically conductive sinuous resistor wire structure 30 therebetween to define a space filled with adhesive. When the adhesive is set the package is held in place. When removal is desired, current is passed through the sinuous wire structure to soften the adhesive to permit removal of the package without damage to the package or the board.

Abstract: An aircraft battery assembly to provide a preheated battery to facilitate aircraft operation in cold temperature. The battery assembly includes a battery housed in a battery box and having a heating jacket wrapped around it. The heating jacket is elongate and rectangular with a width less than the height of the battery and a length sufficient to wrap around the battery with vertical edges that approach one another near a quarter of the battery. The edges have grommets with eyelets. The grommets of the respective edges are laced together to secure the jacket around the battery. The jacket is comprised of inner and outer insulative layers with a heating element sandwiched between them. The jacket is very thin so as to able to readily turn the corners on the battery. The heating element is operated responsive to a thermostat sensing temperature.

Abstract: A charge-coupled device package comprises a substrate of dielectric material and a charge-coupled device die mounted on one main face of the substrate. The substrate is placed in heat exchange relationship with a cold sink, such as a bath of LN.sub.2. A temperature sensor senses the temperature at a location on the main face that is in close proximity ot the die. A film resistor is adhered to the opposite main face of the substrate and receives a current that depends upon the temperature sensed by the sensor.

Abstract: A novel test die for emulating the thermal characteristics of functional product dies includes a plurality of concentric emulator ring configurations fabricated about the die center, each having a plurality of heating resistors approximately forming a rectangle, a plurality of sense diodes located in proximity to the heating resistors and a plurality of hot spot resistors located in proximity to both the heating resistors and the sense diodes. Metallic interconnections are formed on the die which selectively provide each of the heating resistors and hot spot resistors with excitation signals and present signals from the sense diodes indicative of the voltage thereacross.

Abstract: A heater control circuit for the integral heater of a liquid crystal display comprising solid state switches that simultaneously connect and disconnect the high side and low side of the heater from power and ground, respectively, in response to display temperature. A blend resistor is connected between the heater and ground to bleed off accumulated charge that would erroneously drive one of the solid state switches into conduction.

Abstract: A dynamoelectric machine with an axially symmetric rotor and shaft allows the rotor to be reoriented end-for-end within the machine. The machine includes an etched foil heating assembly, an indexable power conduit assembly, and a compartmentalized accessories conduit assembly selectively connected to the frame in a pre-determined manner. Bearing support assemblies for the rotor shaft incorporate adjustment blocks to permit ready alignment of mechanical and magnetic centers.

Abstract: A moisture sensing detector of snow, sleet, ice and rain. The detector includes a sensing probe and coacting control circuitry for receiving the moisture signal from the probe and actuating associated equipment such as, for example, a railroad switch heater. The probe includes sturdy substantially elongated electrically charged aluminum electrodes spaced apart a very small distance (1/8" gap for example) by fiberglass strip insulation. Any moisture (even a drop of water) bridging the small gap completes a circuit between the electrodes which triggers the control circuit into actuating the railroad track switch heater or any like equipment. The electrodes are substantially elongated to provide a large sensing area. A heating unit is secured to one electrode to heat the entire length of the probe thereby melting any ice, sleet and snow (since they do not conduct an electrical current) thus permitting the probe to detect resultant moisture.

Abstract: An electronic thermal printer has a thermal printhead to which is applied a train of pulses which is pulse width modulated. A power switch connects and disconnects the printhead from a DC power source. The pulse train is integrated, scaled and applied as an input to a comparator circuit. The thermal printhead has a temperature sensing diode whose output is applied, as a reference voltage, to the other input of the comparator. During a print cycle, the output of the temperature sensing diode is cut off and the reference voltage is capacitively stored and held as the reference voltage. The output of the comparator circuit clears a latch circuit whose input is provided by a system clock and whose output is connected to control the power switch. The comparator provides an output when the integrated voltage reaches the reference voltage, clearing the latch. Since the latch is supplied with signals from the system clock, a constant frequency is maintained.

Abstract: A battery warmer includes a positive temperature coefficient (PTC) element of a size to maintain the contents of a battery to which it is attached in the range of 45.degree. to .phi..degree. F. in ambient temperatures of -30.degree. to 75.degree. F., and a housing for the PTC element, preferably of foamed plastic. The housing is mounted to a flat side of the battery, either adhesively or mechanically. A method of making the warmer includes securing paper to two broad, parallel surfaces of the housing to provide one surface that will take adhesive and another to bear printed instructions, and which together inhibit warping of the housing during its manufacture.

Abstract: A planar heater for a liquid crystal element includes a thin metal plate having a relatively high specific resistance such as stainless, nichrome, nickel-chrome iron alloy, etc. The thin metal plate is subjected to etching-working to form a mesh-like heat generating body, opposite ends of which are provided with terminal portions for connection into an electrical circuit.

Abstract: Disclosed is a method for removing a hybrid or integrated circuit chip soldered to a support structure. An electrical energy source is applied to the hybrid circuit chip for raising the temperature of the circuit chip sufficiently so as to melt the solderable material which interconnects the chip to the support structure. When the solderable material is melted, the circuit chip may then be removed from the support structure.

Abstract: An improved apparatus and method are disclosed for heating objects, such as electronic chips being bonded to substrates, in which a copper heat exchanger element (12) comprises a circuitous interior passage (26) through which gases pass from a source (30) to be heated by a heater (74) to a desired temperature and to be cleansed of unwanted oxygen by catalytic reaction, prior to entering a furnace chamber (22) heated from below by the heat exchanger element (12) and from above by a further heater (72) and copper plate (60), whereby essentially uniform gas temperature, acceptably low oxygen concentration and fast cycling times are provided in the furnace chamber (22). See FIG. 1.

Abstract: A hermetically sealed encapsulation package for electronic components and integrated or hybrid electronic circuits has a base on which the component or circuit is mounted in the conventional manner and a cover. In one embodiment, the base includes a layer of a material which is able to retain any water molecules which might remain within the package after sealing or which may result from in-leakage from the surrounding atmosphere.

Abstract: A portable thermally insulated case has an outer shell formed of a bottom wall and upwardly extending side walls integral with each other with integral rigid polyurethane foam adhering to the inner surface of each of the walls. A cover, which has rigid polyurethane foam on its inner surface, is hinged to the rear upwardly extending wall to close an access opening at the top of the outer shell. Each of the bottom and upwardly extending walls of the outer shell has a separate container in contact with the inner surface of the polyurethane foam and defining a recess therebetween. The cover has a container supported within the rigid polyurethane foam and substantially closing an access opening at the upper ends of the separate containers adjacent the upwardly extending walls so that the containers substantially surround any object within the recess. Each of the containers has a phase change material therein to supply heat to any object within the recess.

Abstract: A temperature control apparatus detects an actual temperature of an object (e.g., sensor) to be controlled, and compares the actual temperature with a preset target temperature to obtain a difference therebetween, thereby keeping a heater temperature constant. The temperature control apparatus has a temperature rise rate limiter for controlling a temperature rise rate of the object to be controlled so as not to exceed a predetermined temperature rise rate. The object may thus not be damaged by thermal strain which results from a high temperature rise rate.

Abstract: An electric steam iron includes a plastic housing shell forming a hollow handle structure and a soleplate with steam generating means and ports for distribution of steam. A pump actuated by a handle button delivers water from a tank within the housing shell to the steam generating means. The iron is controlled by a low DC voltage electronic control including a printed circuit board disposed in the housing shell away from the soleplate and having means including a power resistor for reducing high AC line voltage to low DC supply to the circuit. The shell and hollow handle structure are open to the soleplate and the printed circuit board is directly exposed to heat from the power resistor.

Abstract: The several clock lines on a burn-in board are monitored by diode ANDing the clock lines to one or two monitor lines, the ANDing circuitry being mounted on the burn-in board and each monitor line being connected through the burn-in chamber back wall to a detection circuit for detecting presence, level, and/or other quality of the signal on the monitor line and giving an indication and sounding an alarm when the desired monitor signal quality is absent.

Abstract: A hybrid or integrated circuit chip is provided with a heating means integral therewith. The heating means is made accessible for application of an external electrical energy source so as to permit removal of the circuit chip after previously being soldered to a support structure or permit soldering of a circuit chip to the support structure.

Abstract: A combined on-board electric network generator and heater for vehicles, having mounted in its housing an armature which supports at least one alternating current coil and, more particularly, three-phase current coils. The combined generator-heater has a drum-shaped rotor, driven by the engine of the vehicle. The housing of this unit is closed and encloses the rotor as well as the armature and is formed with fluid ducts. Within the housing, a cooling-air circulation is maintained which streams over the coils and rotors and cools them, transferring heat to heat exchange elements which form part of the housing. A cooling fluid circulates in the ducts in a loop through input and output ports. The loop closes upon itself outside of the housing. The cooling fluid circulation recovers heat losses in the generator and makes the heat available for heating the passenger compartment of a vehicle.

Abstract: A closed loop integrated circuit temperature stabilizer 10 has an on-chip temperature sensor 12 for supplying a voltage indication of temperature to an op amp 22 which maintains chip temperature equilibrium by controlling a load transistor 30 which draws current through on-chip heating means 16.

Abstract: Controlled heater apparatus for selectively heating a solid state circuit chip and the substrate upon which it is mounted by a solder bump so as to cause substantially equal expansion and contraction in the chip and substrate to relieve stress on the connecting solder bump.

Abstract: An air data sensor device, such as a pitot, total air temperature sensor, etc., includes an elongated probe having a sensor therein for sensing air flow parameters and a strut for positioning the probe in a desired position on an air vehicle. To avoid ice build-up on the device causing erroneous sensing of air flow parameters a substantially constant wattage electric resistive heater is provided in the probe for deicing. A PTC (positive temperature coefficient) resistive heater is disposed in the support at a location thermally isolated from the probe heater but in thermally conductive relationship to the external surface of the support. The PTC heater is connected in series with the probe heater and continuously varies heater power in response to the rate of heat dissipation at the external surface of the sensor device thereby preventing burn-out of the probe heater and erosion of the probe.

Abstract: A ceramic substrate includes a multiplicity of alternately screened and fired conductor and dielectric levels, with interconnections between levels through small via holes in the dielectric layers or alternately by means of crossovers. Thick film resistors are incorporated throughout the ceramic substrate, wherever needed, and the thick film resistors are printed and trimmed through windows which extend through any upper layers. In addition, resistors may be printed directly on top of the dielectric layers where necessary. Selective area hermetic sealing is utilized only for those chips and wire bonds which require environmental protection by placement of a ring frame seal encircling the selected area and over insulation on substrate conductors which are routed directly beneath the sealing area. A lid is directly soldered to the frame and, before final sealing, a proper environment is created within a sealed area.

Abstract: An electronic package is mounted by its leads in an inner hermetically sealed package in an atmosphere of dry nitrogen gas at about 50 torr gas pressure. Leads extend through hermetically sealed electric feedthroughs into an outer enclosure which is maintained at a vacuum of at least 1.times.10.sup.-4 torr. Electrical leads which extend substantially the entire length of the interior space of the outer enclosure pass out of the outer enclosure at first ends of the leads through hermetically sealed electrical feed-throughs and at second ends electrically communicate with and structurally support the leads from the inner enclosure so that the inner enclosure is disposed between the first and second ends. The surfaces of the inner enclosure and the interior surface of the outer enclosure are electropolished.The electronic package consists of a central core sandwiched between beryllium oxide heat spreaders on which are mounted heaters in the form of power transistors.

Abstract: An evaporated thin-film platinum resistance thermometer interleaved with a nichrome heating element on a sapphire substrate so as to calibrate infrared detectors and allow accurate control of the output signals of such detectors.

Abstract: A semiconductor integrated circuit supporter on which a heating element is dielectrically provided, said supporter comprising a package, printed circuit board, mother board, etc. for supporting a semiconductor integrated circuit which includes devices such as transistors.The heating element provided on said semiconductor integrated circuit supporter is capable of heating the whole or a required part only thereof so that the semiconductor integrated circuit is preheated to a temperature required for its normal operation with precision and stability thereby improving the accuracy and reliability of various devices of which a semiconductor integrated circuit is composed as well as the control by said devices.

Abstract: Apparatus for compensating thermal drift of temperature sensitive circuitry in an integrated circuit by heating the temperature sensitive circuitry by applying power to a heating element in the integrated circuit, testing the temperature sensitive circuitry, and trimming a thin film resistor in accordance with the testing results. The heating element is an integrated resistor adjacent to or surrounding the temperature sensitive circuitry. The integrated circuit further includes a thin film compensating resistor which affects or determines the degree of temperature sensitivity of the temperature sensitive circuitry. As the temperature of the temperature sensitive circuitry is increased, testing apparatus is utilized to measure a temperature sensitive parameter of the temperature sensitive circuitry.

Abstract: An electric heating device for heating the interior of a cabinet containing electrical apparatus, such as a switch or distribution apparatus, to prevent sweating or condensation therein, includes at least one PTC electrical resistance heating and temperature self-regulating heating element situated in the interior of an elongated body made of thermally conductive material that is thermally connected to a radiator. The radiator is formed by a pair of flat base plates extending laterally from opposite sides of the body and radiator fins extending only from the base plates and only from one flat side thereof. The body is a massive hollow element having a wall thickness greater than that of the base plates and fins and a height greater than the thickness of the base plates. The body, base plates and fins are formed as a one piece extrusion. A permanent magnet may be used to secure the body to the interior surface of a steel cabinet.

Abstract: A strictly capacitive sensor for an electrical hygrometer comprises an electrode in the form of a slice of doped silicon supporting a dielectric layer of hygroscopic material which in turn supports a further and permeable electrode, while the surface of the silicon which supports the dielectric layer is oxidized to provide an impermeable barrier layer which prevents the sensor acting resistively.

Abstract: A method of starting the engine of a vehicle, such as an automobile, over a wide range of ambient temperatures, such as in cold temperatures below 32.degree. F. and warm temperatures above 32.degree. F. The method includes the steps of energizing the starter motor of the vehicle from the vehicle battery only and starting the vehicle at warm temperatures, and providing an auxiliary battery connected in combination with the vehicle battery for starting the vehicle at cold temperatures. The invention comprehends maintaining the auxiliary battery warm separate from the vehicle during low ambient temperature conditions when the vehicle is not in use. Alternatively, the invention comprehends utilizing a small, low capacity battery which may be incapable of starting the vehicle when the battery is at the cold temperature, but which may itself start the vehicle when the battery is at warm temperatures.

Abstract: In a lead screw drive, such as that used in a lightweight lathe or milling machine for driving the workpiece relative to the cutting tool, the core of a drive nut is made of a material having a relatively low melting temperature, such as babbitt metal or a relatively rigid thermoplastic material. The low melting point material is contained within a nut housing as of steel. The openings in the nut housing for passage of the lead screw are scaled in a fluid type relation by means of elastic sealing members as of silicone rubber having a melting point above that of the relatively low melting point core portion of the nut. An electrical heating cartridge element is contained within the nut housing in good thermally conductive relation with the low melting point core material.

Abstract: An apparatus and method for measuring and monitoring blood oxygen content and local perfusion factor. A transcutaneous gas measurement probe is heated by application of an electric current to a semi-conductor device housed therein. The heat developed in a semi-conductor device heats the probe to a constant temperature under the control of a temperature monitoring and regulating circuit and the amount of power applied to the semi-conductor device is measured by multiplying the current conducted through the semiconductor device by the voltage across it to provide a measurement of local perfusion factor. An alerting device is provided to signal when blood oxygen content and local perfusion factor are outside a predetermined acceptable range.

Abstract: Apparatus and method for compensating thermal drift of temperature sensitive circuitry in an integrated circuit by heating the temperature sensitive circuitry by applying power to a heating element in the integrated circuit, testing the temperature sensitive circuitry, and trimming a thin film resistor in accordance with the testing results. The heating element is an integrated resistor adjacent to or surrounding the temperature sensitive circuitry. The integrated circuit further includes a thin film compensation resistor which affects or determines the degree of temperature sensitivity of the temperature sensitive circuitry. As the temperature of the temperature sensitive circuitry is increased, testing apparatus is utilized to measure a temperature sensitive parameter of the temperature sensitive circuitry.

Abstract: Disclosed are humidity sensor structures, and fabrication techniques, which result in uniform and reliable humidity sensing, reliable electrical connections in small sensors, and simplified and inexpensive manufacture.

Abstract: An improved oven (10) for maintaining the junctions of a plurality of reference thermocouples at a common and contant temperature. The oven (10) is characterized by a cylindrical body (12) defining a heat sink having an axially extended cylindrical cavity (14), a singularized heating element comprising a unitary cylindrical heating element consisting of a resistence heating coil (20) wound about the surface of a metallic spool (18) having an axial bore (22) defined therein and seated in the cavity, an annular array of radially extended bores (30) defined in the cylindrical body (12) and a plurality of reference thermocouple junctions (32) seated in the bores in uniformly spaced relation with the heating element, and a temperature sensing device (28) seated in the axial bore for detecting temperature changes as they occur in the spool and circuit (46) for applying a voltage across the coil in response to detected drops in temperatures of the spool.

Abstract: Apparatus for protectively housing radiation transmitting or receiving eqment is provided with a window in the form of a spherical segment, which is formed of material transmissive to radiation of the frequencies of the equipment, and which has a seating surface. A mounting for providing forces to support the window and to resist external pressure applied thereto has a bearing surface, and a heated bearing gasket abutts both the bearing and seating surfaces. The gasket is provided for resisting wear between the bearing and seating surfaces, and also for transferring selected amounts of heat to the window. A heat regulator is coupled between the window and the gasket to control the amount of heat transferred to the window by the gasket, and structure is provided for continuously joining the window, the mounting and the gasket.

Abstract: A motor heat control circuit is provided for heating an electrical motor during the time of motor shutdown, with the circuit functioning to interconnect a winding of the motor with a source of alternating current voltage for substantially an entire half-cycle of the alternating current voltage but only at intervals comprising a selected plurality of cycles of the alternating current voltage. In its preferred form, the motor heat control circuit is adapted to be connected in shunt circuit with a main motor contactor normally interconnecting the motor winding with the source of alternating current voltage, and includes a controllable semi-conductor switch controlled by digital counting logic which is responsive to clock pulses developed from the alternating current voltage.

Abstract: A high-voltage network includes at least one overhead power transmission line provided with an insulated conductor,which line connects busbars of transmitting and receiving substations. A source for melting the ice is connected, in the course of ice melting, to at least one disconnected phase of the power transmission line. The insulated conductor is joined during ice melting to at least one disconnected phase of the overhead power transmission line from its opposite ends.

Abstract: The high-voltage network for areas of increased intensity of icing comprises supply and distribution substations, an overhead transmission line connecting the supply and distribution substations, an additional overhead transmission line leading from the distribution substation, a rectifier for melting the icing with direct current installed at the supply substation, and a switching center positioned at the distribution substation and connecting at least one conductor of the overhead transmission line to a different number of conductors of the additional overhead transmission line when the icing is to be melted on conductors of the additional overhead transmission line by the direct current.

Abstract: A high-voltage electrical network comprises neutral conductors, at least two of them being grounded, and at least two ground circuits, at least one of them being connected to a neutral conductor and functioning as a first operational grounding means which is a part of a circuit for melting the icing by direct current on one of the lines of the high-voltage electrical network. The ice melting circuit is also provided with at least one more series-connected operational grounding means, a heated circuit of a high-voltage electrical network, a device for melting the icing by direct current on one of the lines of the high-voltage electrical network and a ground used as a return conductor.

Abstract: A low inductance, rapid response, heater for silicon photodetector and microcircuit applications is realized by depositing on a substrate surface a heater whose contact terminals and resistance element are configured to eliminate electrical noise due to the induced currents that commonly result from on-off switching action. The heater geometry utilizes a concentric ring configuration and consists of an inner disc-shaped contact terminal, a ring-shaped resistive heater element surrounding the disc-shaped contact terminal and an outer peripheral contact terminal surrounding the heater element. The heater is operated by means of an electrical current flowing in a radial direction through the circuit comprising the outer peripheral contact terminal, the annular resistive heater element and the inner contact terminal.

Abstract: A liquid crystal cell having an internal resistance-type heating means for rapid cell warm-up, and for maintaining the cell at a predetermined temperature while it is operating as a visual display. The heating means comprises electrically symmetrical transparent films of resistance material on facing surfaces of transparent members sandwiching the liquid crystal material. The resistive films are covered with an insulating film, on which is disposed the control electrodes for the electro-optic display of the liquid crystal cell. Heating voltages, higher than those required to operate the visual display, can be safely applied in parallel across the films without interfering with a concurrent visual display.

Abstract: A high-voltage network for areas with high rates of icing includes load current circuits including aerial electric power transmission lines and a transformer for melting of an ice coating, the primary winding of the transformer being connected in series with a load current circuit and the secondary winding of said transformer being connected to conductors of one of the aerial electric power transmission lines.

Abstract: The device for melting the icing by direct current through conductors of an overhead power transmission line comprises a rectifier coupled during the ice melting period by its lead-out wires to the disconnected conductor of the power transmission line, a ground wire, and a current filter set in resonance to the line at the commercial frequency, which is, for example, a capacitor bank connected in series to a reactor, whose lead-out wires are connected in parallel to the direct-current voltage lead-out wires of said rectifier.This device can be used to melt the icing by direct current through conductors and cables of overhead power transmission lines within a voltage range from 110 to 220 kv and more.

Abstract: A plate of magnetic material is provided in close proximity to a flat transformer in a manner to effectively generate heat due to eddy currents induced in the plate by leakage magnetic flux from the flat transformer, whereby a charger, including the transformer and the plate, can charge a battery while also warming the same.

Abstract: In a method for de-icing aircraft surfaces by means of a plurality of electrical resistance heaters which are sequentially supplied with heating current, the delivery of current to each heater being effectuated during a succession of cycles each constituted by a heating period during which heating current is supplied to the heater and a nonheating period during which no current is supplied to the heater, thereby controlling the average current supplied to the heater, the range of ice accumulation rates to which the de-icing process can adjust is enlarged by controlling the duration of the heating periods in dependence on the temperature at the resistance heaters and by controlling the duration of the nonheating periods in dependence on the water content of the atmosphere surrounding the aircraft.

Abstract: Low-level "trickle" electric heater means in diverse forms prevents hygroscopic moisture accumulation adjacent relatively open or exposed ends of refractory-encased conventional electrical heating elements, thereby to prevent excessive leakage current through refractory otherwise potentially conductive with moisture buildup which may present a hazard at such time as the element is initially turned on.