Abstract: A Joule effect electric furnace for goldsmith, dental and the like melting processes comprises a graphite crucible which constitutes by itself an electric resistance element suitable for the Joule effect heating and is connected to an electric power supply.

Abstract: A self-regulating electric heater particularly useful for heating compressor lubricant and the like is disclosed in which a cylindrical body of electrically insulative ceramic is formed with an axially extending generally parallelepiped shaped slot in communication with an end of the body. A positive temperature coefficient of resistivity (PTC) resistor, configured slightly smaller and complementary with the slot, is disposed therein. Axially extending grooves are formed in two opposed parallel walls of the body which, with two other cooperating walls, define the slot. The grooves are located on opposite sides of an axial plane perpendicular to the opposed walls. A platform is formed in each groove to serve as a stop surface to limit the insertion of spring biased terminals which are inserted in the grooves to provide electrical connection with the PTC resistor.

Abstract: A heater is disclosed having a PTC thermistor heating element rigidly wedged in an intermediate space of the member to be heated by use of at least one wedge-shaped member. The wedge-shaped member has a surface which is at least the size of the heating elment so an optimum heat transmission is guaranteed.

Abstract: The invention relates to heating elements comprising conductive polymers which are capable of undergoing a change in dimension. The heating elements comprise a laminar member composed of a conductive polymer and two laminar electrodes connected directly or indirectly to opposite faces of the laminar member, and there are apertures, for example slits, passing through the thickness of the element so that at least one planar dimension of the element can be changed by changing the shape of the apertures. The apertures through the element facilitate its dimensional change. Preferably the laminar member exhibits PTC characteristics. The heating elements are particularly useful in the form of articles in which the element is attached to a heat-responsive sheet, for example a heat-recoverable polymeric film.

Abstract: A fuel burning apparatus which receives liquid fuel and converts it into a fine fume which is then mixed with air and conveyed to a burner where the mixture of the fuel and air is burned. The fuel is supplied from a supply tank and dripped onto a heating element having a spiral path formed around its outside. The drop of fuel are collected by means of a funnel placed near the end of the heating element to catch the drops and direct it onto the spiral path. As the drops of fuel proceed along the spiral path around the heating element, the fuel is converted into fine fumes. The heating elements are positioned in a mixing chamber which includes an air inlet to permit air under low pressure to pass into the mixing chamber and mix with the fumes of the fuel. The mixture then passes out of the mixing chamber into a storage chamber which provides the supply of fuel and air to a burner.

Abstract: A fuel oil supply system for providing fuel oil to a heater in a building includes a storage tank, a gravity feed supply line running from the fuel oil tank to the building, a fuel oil heater in the building receiving the fuel oil from the supply line, and a canister filter connected in the supply line. A means for heating the canister filter includes a heater enclosure defining a filter cavity which is sized to receive the canister filter. The heater enclosure includes a substantial cylindrical lower portion and a substantial cylindrical cap portion which interfit to enclose the filter. The cap portion defines openings for passage of the supply line therethrough and the lower portion and the cap portion are joined by set screws. An electrical heater in the filter cavity comprising a light bulb positioned below the bottom of the filter provides a source of heat to the canister filter. Power is supplied to the light bulb by a power cord including a thermostat.

Abstract: An electric heating element of the type having a metal tubular sheath, a resistance conductor within the sheath, a terminal pin connected to an end of the resistance conductor and having an outer end projecting outwardly of the open end of the sheath, electric-insulating, heat-conducting material holding the resistance conductor and terminal pin spaced from the inner surface of the sheath; the improvement comprising a spade-type terminal on the outer end of the terminal pin, the spade-type terminal being formed as an integral part of the terminal pin by a coining die operation.

Abstract: An electric radial blade type heating element is provided for industrial furnaces or other heated devices in which the electrical conductors are relatively thin flat strips or blades, rectangular in cross section and free floating relative to the insulating support structure of the element. The conductors are arrayed in a radially diverging relationship to maximize the exposure of the radiating surfaces which minimizes the pocketing of released heat and overheating of the elements. Means are provided to pass a fluid over the conductors when the element is mounted within a radiant tube to reduce oxidation of the element and the interior surface of the radiant tube. The heating element support structure is not dependent on the conductors for strength or rigidity, thereby rendering the element equally suitable for vertical as well as horizontal installation. The element may be used to directly heat a furnace, or may be mounted in a radiant tube to heat the radiant tube.

Abstract: The invention relates to heating elements comprising conductive polymers which are capable of undergoing a change in dimension. The heating elements comprise a laminar member composed of a conductive polymer and two laminar electrodes connected directly or indirectly to opposite faces of the laminar member, and there are apertures, for example slits, passing through the thickness of the element so that at least one planar dimension of the element can be changed by changing the shape of the apertures. The apertures through the element facilitate its dimensional change. Preferably the laminar member exhibits PTC characteristics. The heating elements are particularly useful in the form of articles in which the element is attached to a heat-responsive sheet, for example a heat-recoverable polymeric film.

Abstract: Improved welds for thermoplastic foam insulation spirally deposited about a structure are obtained employing a thin, resistance heated welding blade which beneficially is positioned by means of a four-bar linkage connecting the blade to the blade support.

Abstract: A heating element comprises a resistance heating wire formed with closely adjacent zigzag loops and wound helically on an insulating plate or a pair of such plates mounted crosswise and possibly narrowing conically towards one end. Opposite loops engage the respective edges of such insulating plate, possibly in notches in those edges, and may be pressed on to those edges. The plate may have holes near its edges, the engaging loops being formed with kinks which clip into the holes. Spring clips may be provided for electrical connections to such loops at the edge of such plate and may also be formed with kinks which clip into the said kinks of the loops. The electrical connection to such spring clip may be a cable rivetted, eyeletted or soldered to a cross-piece interconnecting the legs of the clip or may comprise an angled tongue formed at the end of one of the legs to receive a flat plug-in connector.

Abstract: In a ceramic heating element comprising a ceramic substrate having on a surface thereof a resistor pattern of an electrically conductive material and a ceramic electrically insulating layer disposed on the surface of the ceramic substrate with the resistor pattern thereon, the improvement wherein the ceramic electrically insulating layer includes an opening, the resistor pattern exposed by the opening in the ceramic electrically insulating layer being electrically shorted and/or an electrical short-circuiting path previously provided in the resistor pattern being cut whereby the resistivity of the resistor pattern is adjusted to within a particular range, and a heat resistant electrically insulating coating filling the opening in the ceramic electrically insulating layer.

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: An electric heating element for electric resistance furnace comprises a plurality of heater frames which consist of conductive strip material having a sectional shape selected from leg angle-section, channel-section, lip-section, T-section, U-section, V-section, I-section, H-section, Z-section, and W-section and having electric resistance. The heater frames have a configuration coinciding with a sectional shape of an inner wall of a heating chamber of the furnace, and are made and arranged to have an opening portion. Conductive connecting rods are adapted to connect both ends of each of said heater frames to alternatively adjacent ends of adjacent heater frames so as to constitute a single wire resistance body of said heater frames, and a conductive rod connected with one end of said wire resistance body is arranged to pass through said opening portion of said heater frames and facing a power source terminal together with the other end of said wire resistance body.

Abstract: An open coil electric heater wherein the resistance conductor is supported on a frame. The resistance conductor in this instance, instead of being in the form of a single coiled wire, is composed of a plurality of strands of wire so as to reduce the cost of the resistance conductor while providing adequate surface area. The strands of fine wire or flat ribbon wire are braided into a rope which is formed into a series of reaches in customary manner. At least one of the strands is of a material which will provide strength to the wires that primarily generate the heat and thereby prevent sagging of such wires between wire supports. In a preferred form, the wires are loosely braided to form wide open spaces and insulated support members are projected through certain of the open spaces to support the strands in predetermined position.

Abstract: A material heating furnace with a heating element formed of corrugated metal strips which are spaced at one of the ends thereof by a jumper strip which is welded or otherwise fastened to the metal strips. Also, terminals are provided which are slotted so as to alleviate stresses due to bending.

Abstract: A heating element consisting of a metal pipe, an electric resistance conductor inserted into the metal pipe and a heat resistant insulating material filled between said metal pipe and said electric resistance conductor, characterized in that said heat resistant insulating material is one obtained by coating a first insulating material such as particulate fused magnesia with a second insulating material having a lower melting temperature than that of the first insulating material such as a silicone resin, which has been molten, can maintain an insulation resistance of at least 10.sup.3 M.OMEGA. in an atmosphere at 40.degree. C and a relative humidity of 90%.

Abstract: A bilateral heater unit including an elongated sheath in the form of two substantially parallel adjacent leg portions interconnected by a return bend portion formed of the elongated sheath bent back upon itself and integral with the adjacent parallel extending leg portions. Each of the leg portions is provided with a terminal portion extending outwardly from the end of the leg portion and spaced from the sheath. A resistor assembly is secured between the terminal of each of the leg portions and extends along the sheath between the terminals, the sheath between the terminals being filled with compacted powder insulation spacing the resistor assembly from the sheath. The parallel extending leg portions have opposing inner surfaces thereof spaced from one another and the resistor assembly may include at least one electrically conductive member extending within the sheath along the portion thereof for producing a non-heat generating zone thereat.

Abstract: An electrically conductive paper comprising glass fibers is made by dispersing electrically conductive materials i.e. electrically conductive fibers or particles, with the glass fibers of a paper-making slurry. Paper having an electrically conductive layer and a nonconducting layer can be made. Heating panels are made by adhering the electrically conductive paper to a wall in much the same manner as is wallpaper. A positive electrical terminal is applied to one end of the paper and a ground terminal is applied to the other end of the paper. A flow of electricity through the paper causes the paper to heat and to in turn supply heat to the room which the wall faces.

Abstract: A high temperature furnace particularly adapted for fusing crystalline silica includes a housing defining a heating chamber that receives electrically conductive elements with insulators positioned therebetween to establish an electrical flow path for heating the chamber. Resilient gas cylinders located externally of the housing bias graphite connecting rods that extend into the heating chamber to compress and position the conductive elements and the insulators therebetween while allowing expansion thereof during heating of the chamber. Graphite wall panels preferably define the housing heating chamber and have interlocking edges that position the panels relative to each other. Cooperable pairs of resilient gas cylinders at longitudinal ends of the furnace housing compress the wall panels to maintain the edges thereof in their interlocking relationship while permitting expansion during heating of the chamber.

Abstract: A cartridge heater with improved thermocouple comprising a tubular metal sheath with a front end having a central opening therein, a metal plug engaged in and closing said opening, a filler of dielectric material in the sheath rearward of the plug, a resistance wire within and extending longitudinally of the sheath and supported by said filler, said plug having a pair of circumferentially spaced axially extending and radially outwardly opening grooves, a pair of elongate thermocouple wires supported by the filler within the sheath and having front end portions tightly engaged in and between in said opening and grooves, and an annular weld about the foremost line of contact between said sheath and plug and across the forward ends of said grooves.

Abstract: A heating device for installation on the roof of a structure to permit water to flow off the structure from behind a blockage of ice. An elongate, hollow tubular member defines a chamber in which is situated a point heat source. A jacket of insulative material surrounds the tubular member to retard heat loss. One side of the jacket faces the roof and has a channel open to the tubular member such that heat transfer from the tubular member occurs primarily through the channel. When the device is installed on a roof, heat radiated through the channel forms heated passageways through the ice blockage for escape of water.

Abstract: Self-regulating heating element comprising one or more PTC resistors enveloped by a synthetic-material/filler mixture which has a good heat conductivity such as an MgO-SiO.sub.2 -silicon rubber mixture.

Abstract: A high temperature electrical resistance heater for use within a high temperature furnace. The heater is composed of an elongated tubular element having first and second tubular sections contiguous with one another, the first section being of a high resistivity silicon carbide and disposable within a furnace chamber, the second section being of a low resistivity silicon carbide and disposable external to the furnace chamber. An elongated rod of silicon carbide of low resistivity is disposed coaxially within the tubular element and in electrical connection with an end of the first tubular section. The coaxial ends of the second tubular section and of the rod include contact areas for electrical connection to an external power source. The high resistivity tubular section provides efficient heating, while the low resistivity tubular section and coaxial rod provide a conductive electrical path to the heating section while minimizing the heating thereof.

Abstract: Heating for a vibratory spiral conveyor used to react powdery and gaseous substances is accomplished by an expanded metal resistance heater element positioned between adjacent turns of the conveyor.

Abstract: An electric resistor assembly for use in motor starters or other electric apparatus characterized by an elongated mounting strap having terminals at both ends respectively for panel mounting, a plurality of insulating refractory bodies on the strap in end-to-end abutment, one end wall of each body having a bulged portion protruding from the end wall, the other end wall having a cavity corresponding to and receptive of the bulged portion of an adjacent body, and a helical resistance conductor mounted on and surrounding the bodies.

Abstract: A high-temperature parallel-resistance pipe heater is described which is capable of being maintained at a high temperature level of approximately 600.degree. F on a sustained basis and is capable of withstanding temporary occasional heating up to 1,000.degree. F. A twisted pair of flexible electrical conductors with micaceous and fiberglass braid insulation layers have short segments stripped bare on alternate conductors at uniformly spaced intervals along their length, the conductors each including multiple fine nickel-clad copper strands, and a nickel-alloy resistance wire is helically wound around the twisted pair with two bights of the resistance wire engaging many of the strands in each bared segment for establishing numerous points of high unit area pressure contact at the junction between conductor and resistance wire. An anti-fraying agent on the fiberglass braid prevents the fibers from interfering with these points of contact.

Abstract: A thermal display comprising an array of semiconductor heater mesas having a larger cross-sectional area at the display surface than at the support surface. The preferred structure is in the shape of a truncated, inverted pyramid. The novel method includes forming the inverted heater elements by etching trenches in one surface of the semiconductor substrate and forming the heater mesas at the opposite surface, with the trenches defining the individual mesas.

Abstract: The disclosure relates to a ceramic heating device in the form of a cylindrical shape comprising a burnt cylindrical support core of heat-resistant ceramics, a ceramic element disposed around said support core, said element comprising (i) a burnt sheet of heat-resistant ceramics; (ii) a heat-generating resistor pattern, said pattern being hermetically sealed between said sheet; and (iii) a pair of exposed terminals provided onto said sheet and said core, said terminal being connected to said pattern and adapted to be coupled to power leads such that electric power is then applied to said pattern.

Abstract: An improved electrical heating element for a high-temperature furnace including a support structure and an electrical-heating assembly. The support structure includes a plurality of thin, flat, non-conductive plates each having a plurality of spaced apertures therethrough and a plurality of non-conductive spacers smaller than the plates with one spacer interposed between each pair of adjacent plates. The electrical-heating assembly includes a plurality of elongated electrical conductors, preferably U-shaped, each leg extending through one aperture in each plate radially outwardly of the spacers. The conductors are supported by and extend between the plates and the ends of the conductors are interconnected so that the conductors as interconnected define a single tortuous electrical path radially outwardly of the spacers. The interconnection between the conductors maintain the support structure in assembly.

Abstract: An electric heating element of the metal sheathed type, particularly a range surface unit comprising a spiralled metal tube having one closed end and containing compacted refractory insulation material and a helical coil of resistor alloy insulated from the tube and connected at one end to a center return conductor and having both electrical terminations extending from the other end of the tube, the construction being such that in the event of failure of the heating element, the failure will be in a passive manner.

Abstract: A cartridge heater with improved thermocouple comprising a tubular metal sheath with a front end, a metal plug closing the front end, a filler of dielectric material in the sheath rearward of the plug and an elongate resistance wire supported by the filler, said plug having a pair of spaced axially extending through holes, elongate insulating tubes with front and rear ends and engaged in said holes with their front ends spaced predetermined limited distances from the open front ends of the holes, a pair of elongate thermocouple wires with front end portions engaged through the sleeves and projecting forwardly therefrom and rear portions supported in said filler and projecting rearwardly through and from the sheath and metal deposits in the forward position of the holes in the plug in sealing engagement therewith and in heat conducting contact with the thermocouple wires.

Abstract: An electrical igniting unit for cigar lighters, engine ignitor plugs, and the like comprising a wound spiral of resistance ribbon which is carried in a shallow metal cup to span the mouth thereof. The inner end of the ribbon is secured to a metal stud as by crimping and/or welding it in a slotted head thereof. The outer coil convolution is secured to the rim of the cup by forming inward the rim edge into a tight curl which is laid over on the end portion of the coil convolution. A relatively large area of the coil end is thus tightly and securely pinched under continual pressure, to establish a low-resistance effective mechanical and electrical connection between the cup and the coil.

Abstract: A small heater wire winding for a fast warm up indirectly heated cathode includes a spacer wire wound over the heater wire. The main winding and spacer wire are coated with insulation to insure spacing between closely wound turns.

Abstract: A simple, relatively electrically safe self-cleaning food supporting grill construction comprising a serpentine steel tubing for supporting food over a cooking fire and through which an electrical current from a conventional household electrical supply is passed to burn food residues from the tubing, and in which the grill is used in cooking units that render the grill easily accessible to being touched or handled by a person, such as in a barbeque cooking unit.

Abstract: A high temperature unitary electrical resistance heater which is mechanically supported throughout its active length but spaced from a refractory base with the heating element being substantially free of the supporting structure to provide an efficient heater having relatively low thermal inertia while being rigidly supported for high temperature operation. A flat continuous electrical resistor ribbon is folded in a multiple loop helix-like configuration formed of a plurality of straight segments and a repetitive array of folded, overlapped corner portions. A strut is interposed within each folded corner and welded therein, outwardly extending end portions of each strut being rigidly secured in a refractory base structure with the resistor ribbon being spaced along its active length from the base structure.

Abstract: A high temperature unitary electrical resistance heater which is mechanically supported throughout its active length but spaced from a refractory base with the heating element being substantially free of the supporting structure to provide an efficient heater having relatively low thermal inertia while being rigidly supported for high temperature operation. A flat continuous electrical resistor ribbon is disposed in a multiple loop configuration having a plurality of spaced heater segments with flat confronting surfaces and a plurality of legs outwardly extending from an edge of the ribbon and secured within a refractory base to support the ribbon in spaced relation to the refractory base.

Abstract: A heater unit of bilateral construction is formed by forming a resistor assembly of a resistor helix extending between cylindrical terminals and overlapping the same, inserting the assembly in a sheath tube, filling the tube with MgO powder, placing laminated mica end plugs over the terminals and extending into the ends of the tube, bending the tube into a U-shape, pressing the legs of the U together and feeding the pressed unit through swaging dies to deform the tube over the entire length thereof to provide a heater unit of substantially circular cross section and having two legs of substantially semicircular cross section. The resistor helix in the area of the leg portions has a cross-sectional shape corresponding to the cross-sectional shape of the sheath and the terminals and mica plugs within the sheath are flattened to provide a similar cross-sectional shape thereby locking the terminals within the sheath.

Abstract: An electric igniter assembly including a casing in which the major length of the igniter element is enclosed so that only a small portion is disposed in proximity to a gas burner; the electrical connectors for the igniter element and the electrodes that are attached to power leads are disposed remote from the flame issuing from the gas burner as well as being fixedly supported in the casing which includes shock absorbent material to reduce possibilities of breakage of the igniter element. A shield mounted upon the casing surrounds the igniter element so as to readily enable direct ignition of the gas burner and thereafter protect the igniter from direct burner flame impingement.

Abstract: An electrical igniting element for use with ignitor devices such as are commonly utilized in electrical cigar lighters, engine ignitor plugs, and the like comprises a heating element, such as a wound spiral of resistance ribbon, carried on an annular metal holder or cup and spanning the mouth or opening thereof. The inner end of the spiral ribbon is secured to a central metal stud as by crimping and/or welding it in a slotted head thereof. The invention provides improved means for securing the outer coil convolution to the rim of the holder or cup by curling inward the rim edge into a tight curl which is laid over on the end portions of the coil convolution whereby a relatively large area of the coil end is tightly and securely pinched under continual pressure, thereby establishing a low-resistance effective mechanical and electrical connection between the cup and the coil throughout the useful life of the latter.

Abstract: A heater unit of bilateral construction is formed by forming a resistor assembly of a resistor helix extending between cylindrical terminals and overlapping the same, inserting the assembly in a sheath tube, filling the tube with MgO powder, placing laminated mica end plugs over the terminals and extending into the ends of the tube, bending the tube into a U-shape, pressing the legs of the U together and feeding the pressed unit through swaging dies to deform the tube over the entire length thereof to provide a heater unit of substantially circular cross section and having two legs of substantially semicircular cross section. The resistor helix in the area of the leg portions has a cross-sectional shape corresponding to the cross-sectional shape of the sheath and the terminals and mica plugs within the sheath are flattened to provide a similar cross-sectional shape thereby locking the terminals within the sheath.