Abstract: An electrical protective device is described which has two PTC thermistor components which are in the form of plates and are arranged in a common housing. The housing in each case has an opening on two opposite sides, which opening corresponds to the dimensions of the PTC thermistor components such that the PTC thermistor components can be inserted into the housing through the openings. The two PTC thermistor components are electrically isolated from one another in the housing. The PTC thermistor components each have at least two connecting wires, by means of which the PTC thermistor components are locked to the housing.

Abstract: A method of supporting vertically hanging electrical resistance elements for heating furnaces or ovens in industrial operations. Each resistance element includes current-conducting legs that extend downward and upward a number of times, and the element includes along its length a number of ceramic discs that are provided with through-holes through which respective element legs extend. The upper part of the element merges with terminals that are connected to a source of electric current. The element is supported by at least one of the uppermost ceramic discs, wherein the uppermost ceramic disc supporting the element is placed in the insulation of the furnace roof above the underside of the roof. The legs of the element are short circuited at a location slightly or somewhat beneath the underside of the furnace roof with the aid of short circuiting plates.

Abstract: A method for retaining a terminal of a terminal assembly for a positive temperature coefficient resistor/overload resistor (PCTR/OL) assembly includes providing a body having an inner surface, and disposing at least one retaining member to the inner surface. The retaining member is configured to engage the terminal substantially perpendicular to an axis of symmetry of the terminal.

Abstract: An inexpensive positive temperature coefficient thermistor has metal terminals which have been miniaturized without deteriorating the characteristics or sacrificing the reliability of the device. The metal terminals include supporting members and springs constructed such that a total width of the supporting members is smaller than a total width of the springs. In addition, connecting portions at the upper ends of the metal terminals engage with a case main body or a covering member to be retained at predetermined positions.

Abstract: A positive thermistor element is supported by being clamped by first and second resilient contact members that are opposed to each other so as to be disposed along a diagonal and first and second positioning protrusions that are opposed to each other so as to be disposed along the other diagonal of the positive thermistor element. The first resilient contact member is located toward the periphery of the positive thermistor element from the second positioning protrusion and the second resilient contact member is positioned toward an inner portion of the positive thermistor element from the first positioning protrusion.

Abstract: A resistor 1 is used in high-fidelity amplifiers for audio equipment. The resistor 1 includes a cylindrical resistor body 2, a tubular sheath 3 into which the resistor body 2 is coaxially inserted, and a conductive film portion 31a formed on the inside surface 3a of the sheath 3. The conductive film portion 31a faces to a resistance film 22 covering the surface of the resistor body 2 with an annular space 6. An insulating slit 32 is formed at a central point along the resistor axis 1a, separating the conductive film 31 into left and right parts that are electrically isolated from each other. The sheath covering the resistor body 2 prevents distortion of signals in the resistance film 22 caused by extraneous electrostatic induction charges.

Abstract: An improved IDC trim resistor connector assembly made up of a generally open top cup shape connector with side wall slots and an interior first array of terminal posts arranged for passage therethrough of a first lead wire of sensor circuitry. A first stamped metal IDC terminal is push-on mounted on the terminal posts for IDC cradling and electrically and mechanically receiving and connecting to the first lead wire. A conventional trim resistor substrate is loose mounted but accurately positioned on the connector bottom wall and has an “E” pattern of resistive material adapted for center leg laser trimming to calibrate the associated sensor circuitry. A first IDC terminal spring leg overlap contacts one side leg of the trim resistor E-pattern and thereby spring clamps the resistor substrate. A cover is snap-latch mounted on the connector and has an access opening to enable laser trimming of the trim resistor after cover installation.

Abstract: A PCT thermistor arrangement for use in a circuit for demagnetizing shadowmasks of color picture tubes, has at least two PTC thermistor elements which are designed as switching PTC thermistors, are or can be thermally coupled and are or can be electrically connected in parallel.

Abstract: A positive thermistor device includes a positive thermistor element having a pair of opposed electrodes, each of which receives compressive force elastically applied from a corresponding one of spring contact members to hold the thermistor element at a predefined position in the device. When the thermistor device is destroyed, the element breaks into fragments, some of which remain in contact with the spring contact members. The remaining fragments deviate in position to ensure that they do not conduct electricity, resulting in an open state, wherein any current flow is inhibited through such fragments. More specifically, a positive thermistor disk is held within the device so that it is interposed between conductive spring contact pieces and insulative position-alignment projections, which are cross-diagonally situated with respect to each other.

Abstract: The invention relates to a drive apparatus for a liquid crystal display device. The voltage, to be applied to longitudinally and latitudinally arranged liquid crystal cells of the liquid crystal display device, is altered in polarity from field to field and from frame to frame, whereby the occurrence of flicker is prevented. The field discriminating device counts the numbers of lines in first and second fields by synchronizing a vertical synchronizing signal at a leading point of a field time. Thereafter the difference in the number of lines between the first and second fields is detected, the field times being thereby discriminated. When a video signal is erroneous, the field discriminating device provides a field discriminating signal, the level of which is changed alternately from field time to field time.

Abstract: A nonfocused infrared panel emitter and method of making the same. The panel emitter includes a primary emitter positioned between an insulating layer and a secondary emitter. Preferably, the panel emitter comprises a metal foil primary emitter, woven alumina cloth secondary emitter, and alumina silica board insulating layer bonded together by means of an alumina silica binder. In the method of making the panel emitter, a mesh sheet is preferably positioned adjacent the foil and the sheet is vaporized by heating prior to bonding to create a void adjacent the foil to allow thermal expansion and contraction of the foil.

Abstract: The invention relates to a termination for a tubular electric heater, comprising a two-piece body of ceramic or high-temperature plastic which is quickly and easily assembled with a metal spade terminal. The two pieces of the body have interfitting parts which align the pieces longitudinally. One of the pieces has a cavity with a tapered entrance portion for receiving a complementarily-tapered portion of the spade terminal, the latter having a tubular portion crimped about the end of the resistance wire. The invention is adapted for use with a rectilinear heater tube, which may be of glass, quartz or a metal such as aluminum, and simular terminations close respective opposite ends of the tube. The resistance wire is disposed within the tube and is in the form of a helical coil which is tensioned on assembly to draw each termination in abutting relation with a respective end of the tube.

Abstract: An aquarium heater including an elongated heater element including an insulating member and a wire heater extending from one end of the insulating member to the other end of the insulating member and with an outer sheath of insulating material having open and closed ends for enclosing the heater element at the closed end and having an inner dimension larger than the outer dimension of the heater element and with a pair of spacer members disposed individually at each end of the insulating member of the heater element for spacing the heater element from the inner surface of the outer sheath and with the spacer members including means for retaining the ends of the wire heater in fixed positions at each end of the insulating member and with a resilient sealing element disposed from the open end of the sheath to seal the heater element in the closed end of the sheath and with the sealing element including grooves for passing electrical wires for supplying electrical energy to the wire heater.

Abstract: A portable electric radiant heater comprises an insulative housing having a control area and an open front heating area. A hollow fired clay pipe system is disposed in the heating area in serpentine fashion and arranged to radiate heat through the open front. The clay pipe system comprises a plurality of hollow cylindrical pipe segments having a plurality of hollow protuberances extending therefrom. The pipe segments are interconnected together to form a continuous passage extending the length of the pipe system. An electric resistance heating wire extends centrally through the continuous passage in spaced relation to the surfaces defining the passage. The ends of the wire extend into the control area and are connected to a power supply means therein controlled by a thermostatic control having a sensing element enclosed in a clay cylinder disposed in heating area below the heat radiating pipe system.