Abstract: Disclosed is an improved electric heater assembly suitable for heating molten metal, the electric heater assembly having a sleeve comprised of a closed end suitable for immersing in the molten metal. The sleeve is fabricated from a composite material comprised of titanium alloy and having an outside surface to be exposed to the molten metal coated with a refractory resistant to attack by the molten metal; and an electric heater located in the sleeve in heat transfer relationship therewith.

Abstract: The present invention relates to an electric immersion heater utilized in heating liquids contained in a cylindrical container, such as a boiler. The immersion heater is affixed to the side of the container with the heater elements extending through the side of the container through an access hole. The heater elements are contoured so as to allow more than one heater to be installed at a given level through the side of the container.

Abstract: Electrical resistance heating elements, hot water heaters containing such elements, and methods of preparing such elements are provided. The electrical resistance heating elements of this invention can be disposed through a wall of a tank for heating fluid, such as water. They include a skeletal support frame having a first supporting surface thereon. They also include a resistance wire wound onto the first supporting surface and preferably connected to at least a pair of terminal end portions. The support frame and resistance wire are then hermetically encapsulated and electrically insulated within a thermally-conductive polymeric coating. The skeletal support frame of this invention improves injection molding operations for encapsulating the resistance wire, and can include heat transfer fins for improving thermal conductivity.

Abstract: In a heater unit comprising a case 10 which accommodates therewithin an electrical heating element 11 and a temperature sensor 12 for detecting the temperature of the case 10 heated by the electrical heating element 11 to stop the power supply to the electrical heating element 11 when the temperature reaches a predetermined value, there is provided a heat conductive path 20 made of a material having a higher heat conductivity than that of the material making up the case 10 and extending from a region corresponding to the space in which the electrical heating element 11 or heater is placed to a region corresponding to the space in which the temperature sensor 12 or temperature detecting and power supply control member is placed. Thus, the heater unit for an aquarium fish tank is prevented from being extraordinarily heated when the tank has been destroyed.

Abstract: An apparatus for heating water is provided having a water receptacle including a bottom wall and side walls for containing a volume of water therein to be heated. The bottom wall of the receptacle has an exterior surface and an interior surface proximate the volume of water to be heated. The water is heated by a heater contained within the water receptacle and secured to the interior surface of the bottom wall of the receptacle by a securement pin which extends through the bottom wall and is threadably engaged with the heater. The heater is elevated from the interior surface of the water receptacle by a collar of high insulation material which is received within a peripheral groove portion of the heater such that the tightening of the securement pin compresses the rubber collar to create a seal between the heater and the bottom wall of the water receptacle.

Abstract: An extended life electrical heating element for a water heater includes a coiled heating resistance wire having a uniform power output per coil turn. Where the heating resistance wire passes through the sheath at critical areas, e.g. return bends, the number of coil turns per unit length of element is reduced to reduce thermal power output per unit length of the element. The number of coil turns per unit length of element in bend areas may be reduced by simply stretching the coiled heating wire to attain the desired length of resistance wire per unit length of the element. Resistance wires of differing heat output per unit length may be combined with different degrees of stretching to achieve the desired element temperatures. The reduced power at the bend portions reduces element temperature to reduce hard water scaling and significantly extend the life of the element.

Abstract: Polymeric heating elements and water heaters containing these elements are provided by this invention which utilize polymeric materials in contact with electric resistance heating materials and in contact with fluid to be heated. These polymeric materials also provide a substantially self-supporting structure for the resistance heating material. The heating elements include an electrically conductive resistance material capable of heating fluid when energized. The winding is insulated and protected by a polymer layer integrally disposed over the resistance material. The elements are lightweight, inexpensive to produce and use, and minimize galvanic corrosion and lime depositing without sacrificing heating capacity.

Abstract: A tubular high efficiency, non-contaminating fluid heater includes an elongate tubular member having a coil-like configuration and a sidewall which defines an elongate tubular chamber formed from an inert material through which fluid is adapted to flow. The tubular member includes an inlet and an outlet and a plurality of elongate electrical resistance heaters sheathed with the same inert material are disposed in said tubular chamber for heating the fluid as it flows through the tubular chamber.

Abstract: An infrared electric liquid heater includes an elongated emitter unit contained within an outer containment tube to define an annular volume through which the to-be-heated water flows. The emitter unit includes a tubular silica-composition envelope that comes into direct contact with the water to be heated. A tungsten filament is contained within the envelope and is supported along the longitudinal axis by spaced-apart filament supports. The envelope is fabricated from a silica composition discovered to provide unique structural properties; the envelope drawn from a melt (by volume) of 99.88% to 99.94% pure silica (SiO.sub.2), 0.04% to 0.08% crystalline sodium borax (Na.sub.2 B.sub.4 O.sub.7.10H.sub.2), and 0.2% to 0.04% hydroxide of potassium (KOH). This composition has demonstrated a structural strength that allows for a high efficiency in-line, instant-on heater using only a single silica wall separating the electrically energized filament from the liquid being heated.

Abstract: A hot water tank construction, an electrically operated heating element construction therefor and methods of making the same are provided, the electrically operated heating element construction comprising a heating element and an externally threaded fitting for threading into an internally threaded opening in a wall of the tank, the heating element comprising an outer metallic tubular sheath and an inner conductive heater wire insulated from the sheath, the fitting comprising polymeric material, the heating element construction comprising an electrical resistance electrically interconnected to the sheath and being adapted to electrically interconnect the sheath to the wall of the tank, the polymeric material comprising an electrically conductive polymeric material that also comprises the resistance of the heating element construction.

Abstract: A hot water tank construction, an electrically operated heating element construction therefor and methods of making the same are provided, the electrically operated heating element construction comprising a heating element and an externally threaded fitting for threading into an internally threaded opening in a wall of the tank, the heating element comprising an outer metallic tubular sheath and an inner conductive heater wire insulated from the sheath, the fitting comprising polymeric material, the heating element construction comprising an electric resistance electrically interconnected to the sheath and being adapted to electrically interconnect the sheath to the wall of the tank, the polymeric material comprising an electrically conductive polymeric material that also comprises the resistance of the heating element construction.

Abstract: An apparatus and a method of assembling a panel heater for use in a corrosive environment includes a planar heating element, a planar non-conductive carrier for supporting a conductive ground plane thereon, a planar heat sink supporting the heating element, and a fluoropolymer envelope enclosing the heating element, the carrier, the ground plane and the heat sink to protect same from corrosive environments. The heat sink and carrier have a coefficient of expansion which is substantially equal to minimize the effects of unequal expansion and contraction of the heater.

Abstract: A warming bowl for electrically heating lavage and irrigation liquid for use during medical-surgical procedures includes an electric heating device and an automatic thermostatic control to heat and maintain the liquid at a substantially constant temperature. The warming bowl is disposable after use and has an inner and an outer bowl sealed to one another so as to provide an internal sealed region therebetween for holding a battery to power the electric heating device. The inner bowl serves to hold irrigation liquid and supports therein a housing made of low-thermal-conductivity material that houses the electric heating device and the thermostatic control in spaced, substantially thermally isolated relation from one another. A metallic thermal shunt conductor is disposed along and in contact with a portion of the external periphery of the housing and extends over and across the space between the heating device and the thermostatic control.

Abstract: A heater assembly for heating a container of corrosive fluid includes a housing adapted to be located in a container of fluid to be heated, a sealed chamber located in the housing, a heater located in the chamber, an electrically conductive sleeve assembly secured to the housing, and a flexible conduit extending from the sleeve assembly and providing a passageway for conductors providing a source of power to the heater assembly. The flexible conduit includes an electrical conductor connected to ground which is located in the sleeve assembly and the sleeve assembly is swaged to compress the sleeve assembly into the electrical conductor to ground to the electrically conductive housing via the sleeve assembly.

Abstract: A hot water tank construction, an electrically operated heating element construction therefor and methods of making the same are provided, the electrically operated heating element construction comprising a heating element and an externally threaded fitting for threading into an internally threaded opening in a wall of the tank, the heating element comprising an outer metallic tubular sheath and an inner conductive heater wire insulated from the sheath, the fitting comprising polymeric material, the heating element construction comprising an electrical resistance electrically interconnected to the sheath and being adapted to electrically interconnect the sheath to the wall of the tank, the polymeric material comprising an electrically conductive polymeric material that also comprises the resistance of the heating element construction.

Abstract: An improved single heating element for a furnace, and method of designing the circuit is provided.In the method of design and constructing the heating element, the voltage level of the furnace is determined, the operating temperature of the furnace is determined and then the watt level output is selected. A resistance wire is selected and the watt-density of the wire is calculated as if it were to be connected in a single strand in series. If the calculation yields a value greater than the maximum safe watt density, the watt-density is recalculated as if the wire were connected as two wires in parallel, and this calculation is repeated with an additional wire in parallel as many times as necessary to provide a watt-density less than the maximum safe watt density and constructing a furnace heating element with said finally determined number of wires in parallel.

Abstract: A heater for heating dionized water and other liquids which may be very aggressive solvents, the heater constituting one or more heating units having an external cylindrical housing of PTF Teflon or similar material and closed at each end with headers of similar material which contain ports for ingress and egress of the fluid. A concentric inner tubular member of polysilicon surrounds one or more infra red heating elements which, when energized, radiate intense heat into the chamber within the inner tube. This tube acts to confine and reflect the heat back into the chamber thereby heating the liquid to a high temperature very quickly. Relatively little heat passes through the wall of the inner tube to the surrounding chamber. Liquid is directed into the outer chamber, across the length of the inner tube, through a passage at the opposite end and into the inside chamber. The flow across the other surface of the inner tube is warmed somewhat but insufficiently to damage the outer tube.