Abstract: A valve is provided having a circuit that includes an electrical conductor with a temperature-dependent electrical resistance. The electrical conductor is connected in series to an electrical series resistor, which includes a parallel circuit of a non-reactive wire and an NTC resistor. The electrical conductor includes a coil wire wound into a magnetic coil that is operable to move an armature to open or close the valve. The effect of the operation of the valve itself on the magnetic force of the coil is minimized by arranging the NTC resistor to be thermally coupled with the coil wire.

Abstract: An overcurrent protective wire wound resistor has a core, a second contact cap and a resistance wire. A first contact cap and a resistor connection seat are respectively mounted on two ends of a rod of the core. A low melting-point conductive layer is mounted around the rod and connected with the first contact cap and the resistor connection seat. A high-temperature contractive insulation layer is mounted around the low melting-point conductive layer and the first contact cap. The second contact cap is mounted around the contractive insulation layer. The resistance wire is connected to the resistor connection seat and the second contact cap. When current through the resistance wire abnormally increases, high temperature of the resistance wire melts the low melting point conductive layer to shrink the contractive insulation layer and open the low melting-point conductive layer and the resistor, thereby protecting the circuit connected to the resistor.

Abstract: A heating element has a flat, flexible strip of electrically insulating material around which is wound a conductor wire. A layer of fixing varnish covers the turns of the conductor wire and the flat strip. Two clips attached to the ends of the strip provide electrical contact with the conductor wire and serve to attach two electricity connection cables. The heating element can be bent without this affecting its ohm value since the fixing varnish prevents the turns of the conductor wire from moving when the strip is being bent.

Abstract: The present invention relates to an inorganically insulated heater having a long life for use in air flow sensors, cathode ray tube cathode heaters etc., wherein the distribution of inorganic insulating particles of the whole insulating layer is made uniform and thereby the development of cracks and the like in the insulating layer is reduced and breaking of wire and dielectric breakdown occur with difficulty even at high temperatures and under strong vibrations.

Abstract: A winding of noise suppressing high tension resistive electrical wire is disclosed which comprises a reinforcing fiber cord bound by immersion in a low-viscosity liquid resin binder, an elastomeric coating layer formed on a surface of the fiber cord by application of a liquid rubber paint, a metallic resistive wire wound around the coating layer, and an insulating protective layer. The outer diameter of the winding may be less than about 7 mm.

Abstract: An improved electric resistance heater assembly for soldering tools, glue guns, hair dryers, heat pencils, paint removers, etc., includes, as the core of the assembly, an open-ended tube of a ceramic material having good electrical insulation properties with good thermal conductivity, low heat capacity and a high softening temperature. A conduit extends lengthwise through the wall of the tube from end to end thereof and first and second spring-tempered split metallic compression bands of smaller diameter than the tube are placed at each end of the tube and retained thereon by compressive stress. A plurality of turns of resistance wire are wound about the outer periphery of the tube between the bands with each end of the wire welded to a respective one of the bands. An first electric lead is welded to the first band. A second electric lead is welded to the second band and extends lengthwise through the conduit and exits the conduit near the first band.

Abstract: An electric heater assembly for tools having a removable heated tip includes a tubular metal base having an open end adapted to removably receive and hold the end of the tool tip. A coating of ceramic electrical insulation material is provided on a portion of the exterior of the base and a length of Nickel-Iron alloy resistance wire is wound on the ceramic coated portion. Electrical lead wires are connected in lapped relationship to the respective ends of the resistance wire. Each lead wire includes a first portion lying between several turns of resistance wire and the ceramic coating on the base and a second portion bent back and overlaying the several turns of resistance wire. The second portion is wrapped with at least one additional turn of the resistance wire. A coating of ceramic electrical insulation material is provided over the resistance wire and the terminals to seal the same from the deliterious effects of the atmosphere.

Abstract: A heating element is comprised of [A] a shaped, electrically insulating substrate, said substrate including a reinforced polyimide composite, [B] a continuous, electric resistor element in entwining relationship with, and at least partially inlain within said composite [A], said electric resistor element being coated with a thermostable electrically insulating coating, and [C] means for coupling said electric resistor element [B] with an electric power source. Techniques for the fabrication of such heating elements are also disclosed.

Abstract: A wire wound resistor is vertically disposed in a vessel. The resistor has a former of between 20 mm and 45 mm diameter and resistance wire of a resistance of between 1 and 4 ohms per turn connected in the circuit of an A.C. bridge circuit. Impedance change is indicated on a display unit calibrated to indicate the change in level of liquid e.g. milk in the vessel. The resistance wire is laid on the former by applying ultrasonic sound energy to soften the former which is of polysulfone or polycarbonate and the wire embedded in the softened former material. The vessel is shaped at the lower end to assist in giving linear readings when the level of liquid is low.

Abstract: An oil heater for heating lubricating oils having infrared energy absorbtion peaks within infrared wavelengths ranging from 2.5 to at least 15 microns comprises an electrical infrared heating element coupled to an oil cock and adapted to contact the oil within an oil reservoir containing the oil to be heated when the oil cock is seated in an opening in the reservoir. The infrared heating element has an infrared imission spectrum at 400.degree.C ranging from 2.5 to at least 15 microns to match the infrared absorption spectrum of the oil contained in the reservoir and the relative strength of the radiation emitted between the wavelengths of 5-15 microns average at least 50% of the relative strength of the radiation emitted between the wavelength 2.5 to 4 microns.

Abstract: A resistance thermometer sensor is provided by forming a path of electrically conducting material secured on an insulating base. The path is shaped as a loop having two side-by-side portions. A shorting bar connecting across these portions to short circuit part of the loop is adjusted along their length to trim the ice point resistance of the sensor as required. When suitably adjusted, the shorting bar is fastened in position, for example by welding. In one example, the sensor comprises a bifilar helix of resistance wire wound and secured on a cylindrical former.

Abstract: A wire wound resistor is vertically disposed in a vessel. The resistor has a former of between 20 mm and 45 mm diameter and resistance wire of a resistance of between 1 and 4 ohms per turn connected in the circuit of an A.C. bridge-circuit. Impedance change is indicated on a display unit calibrated to indicate the change in level of liquid e.g. milk in the vessel. The resistance wire is laid on the former by applying ultrasonic sound energy to soften the former which is of polysulfone or polycarbonate and the wire embedded in the softened former material. The vessel is shaped at the lower end to assist in giving linear readings when the level of liquid is low.