Abstract: A direct probing temperature regulation and overheat protection system for immersion heater includes a bimetal device adapted to receive thermal energy that is stored in the probe type temperature sensor. The bimetal device opens an electrical contact when the temperature of the bimetal device is reached. The displacement of the bimetal device that drives the electrical contact is a function temperature of the bimetal device that is a function of the resultant heat energy stored in the probe type temperature sensor. The probe type temperature sensor is immersed vertically in the operation liquid that gains heat from the heating element of the immersion heater. In the normal operating condition the displacement of the bimetal device is a function of heat gain from the operation liquid heat loss to surrounding and heat gain from the heating element. In the boil dry operating condition, the displacement of the bimetal device is mainly a function of heat gain from the heating elements that increase rapidly.

Abstract: An improved aquarium heater and particularly an aquarium heater that has a protective device adjacent to an electric heating coil to cut off the electric circuit when the heater is overloaded to prevent the heating coil from continuously heating to avoid risks and hazards includes a glass tube housed a circuit board in an upper section thereof, a heating coil located below the circuit board connecting to the circuit board, a control plug sealed the top opening of the glass tube, and a protective device bridging the heating coil and the circuit board. The protective device cuts off circuit operation when total circuit is overloaded and overheated to ensure safely use of the heater.

Abstract: A pressureless electric water heater for domestic use having a cylindrical double-walled tank for holding a quantity of a heat transfer liquid such as water. Cold water enters a copper coil immersed in the heat transfer liquid. The heat transfer liquid is heated by an electric heating element that extends down a double-walled top. The inner walls and the outer walls of the tank and the upper and lower walls of the top may be spaced apart using any convenient spacing distance, in order to accommodate an amount of thermal insulation, such as fiberglass, foam, cellulose or cardboard, preferably includes open air spaces between the linings of insulation or between a lining of insulation and a wall or surface.

Abstract: A control system for a hot water heater includes a reservoir for containing hot water, a cold water feed for the reservoir, a hot water exit for the reservoir and means for supplying energy to heat water in the reservoir. A temperature monitoring probe associated with the reservoir monitors the temperature of the reservoir. The frequency of removal of water from the reservoir is monitored. There are means for relating the temperature and frequency of water removal to control the operation of the energy means for supplying heat to the reservoir. The frequency of water usage is signaled by monitoring the water temperature in the reservoir, the water flow from the reservoir, or the pressure of water in the reservoir. Based upon the frequency determination, the setpoint of the heating system can be adjusted so that stacking is avoided.

Abstract: A pressureless electric water heater for domestic use having a cylindrical double-walled tank for holding a quantity of a heat transfer liquid such as water. Cold water enters a copper coil immersed in the heat transfer liquid. The heat transfer liquid is heated by an electric heating element that extends down a double-walled top. The inner walls and the outer walls of the tank and the upper and lower walls of the top may be spaced apart using any convenient spacing distance, in order to accommodate an amount of thermal insulation, such as fiberglass, foam, cellulose or cardboard, preferably includes open air spaces between the linings of insulation or between a lining of insulation and a wall or surface.

Abstract: An integrated heater and controller assembly for monitoring and controlling the heating of a process in a reservoir is disclosed. The assembly includes a heater, a coupling adapter, a control unit, and a temperature sensor. The heater attaches to the reservoir and has a heating element extending into the process. The coupling adapter includes a first tubular portion and a second tubular portion. The first tubular portion attaches to the heater. The second tubular portion attaches to the control unit. The first tubular portion is rotatably attached to the second tubular portion. Wires from the control unit communicate through a pathway in the first and second tubular portions and connect to the heater. The control unit has control circuitry to control the power supplied through the wires to the heater. The heater may also have a thermowell that extends into the process.

Abstract: A thermostatic heater device for liquids, in particular for the water of aquariums, comprising within a tubular casing: a rigid support (2) constructed of electrically insulating, heat-conducting material, at least one layer of electrically insulating, heat-resistant flexible film (14) wound about said tubular support, at least one resistive element (16) arranged on a dielectric film wrapped about said first flexible film, a layer of a second electrically insulating, heat-resistant flexible film (14) wound about said dielectric film already wrapped about said layer of first flexible film, means (22) for connecting said resistive element to the electrical supply, and hydraulic sealing means (4, 6) between said tubular support (2) and said casing (8).

Abstract: The invention relates to a device for controlling the power consumption of one or more electric resistance heating element in a vessel containing a heatable liquid, at least one inlet for receiving a liquid having a first temperature, at least one outlet for removing liquid having a second higher temperature, and at least one thermostat for directing power to at least one heating element. The device has a detector for detecting one or more predetermined conditions in the vessel relating to the amount of liquid having the second higher temperature remaining in the vessel, and for generating an initiating signal corresponding to the predetermined condition. A controller is responsive to the initiating signal, and is configured for outputting a corresponding switching signal. A power modulator is responsive to the switching signal, and is configured for modulating power to at least one heating element.

Abstract: A control system for a hot water heater includes a reservoir for containing hot water, a cold water feed for the reservoir, a hot water exit for the reservoir and means for supplying energy to heat water in the reservoir. A temperature monitoring probe associated with the reservoir monitors the temperature of the reservoir. The frequency of removal of water from the reservoir is monitored. There are means for relating the temperature and frequency of water removal to control the operation of the energy means for supplying heat to the reservoir. The frequency of water usage is signaled by monitoring the water temperature in the reservoir, the water flow from the reservoir, or the pressure of water in the reservoir. Based upon the frequency determination, the setpoint of the heating system can be adjusted so that stacking is avoided.

Abstract: A control system for bathers includes an electronic controller which controls operation of an electric heater assembly connected in a water flow path for heating water. The heater assembly includes a heater housing and electric heater element. A solid state water temperature sensor apparatus provides electrical temperature signals to the controller indicative of water temperature at separated first and second locations on or within the heater housing. The presence of water in the heater housing is detected electronically, by turning on the heater, and monitoring the temperature sensors for unusual temperature rises or other faults for a period of time thereafter. A solid state water presence sensor apparatus can also be used to determine the presence of water within the heater housing, providing electrical water presence signals to the controller indicative of the presence or absence of a body of water within the heater housing.

Abstract: A water heater having a water tank and multiple electric resistance heating elements extending into the water tank for heating water in the tank. The water heater includes a proportional band temperature controller for conducting electric power to the electric resistance heating elements in bursts. Each burst of electric power is followed by a period during which the temperature controller does not conduct power to the electric resistance heating element. In one embodiment, each burst of electrical power lasts for about 95% or less of a cycle comprised of one burst of electric power followed by the period during which the temperature controller does not conduct electric power. Further, activation of the heating elements by the controller is carried out in a sequential or other timed or controlled fashion to permit uniform heating of the water in the tank.

Abstract: A domestic water heater 10 includes a water meter 14 to count the units of water used each day and has a timer 17 to time the heating cycle each day. A programmable means 18 stores the water usage and heating data for a sixty day period and using statistical techniques determines the time period required for heating the water in the tank 10. The means 18 also stores power load curve data from the power generator and matches the required heating time to an appropriate portion of a low in the power load curve. The tanks may be placed in any one of 9 groups and a tank in each group will by virtue of the program in means 18 center the mid point of the calculated heating period on the same time during the off peak period. Tanks fitted with such controllers can be allocated into one of two or more categories to enable a power utility to reallocate the water heater power load into low cost periods of the power load curve.

Abstract: A fluid heater has a fluid pipe through which a fluid flows. A radiant heating element is enclosed in a quartz mantle. The fluid pipe is concentrically arranged about the quartz mantle. A first temperature sensor is positioned at a section of the outer circumference of the fluid pipe opposite the heating element.

Abstract: A heater, humidifier or fan has a control circuit including a microcontroller having an algorithm for controlling power to the appliance. The power to the appliance is varied in accordance with a target temperature/humidity signal and an actual temperature/humidity signal. Preferably, a sensor electrically connected to a clock oscillator input of the microcontroller is used to vary the clock oscillator frequency in response to changes in ambient temperature/humidity. The frequency of the clock oscillator varies in response to changes in temperature/humidity and the microcontroller in response to the frequency of the clock oscillator variably controls the power to the appliance.

Abstract: A water heater heating element including a base member adapted to extend through and sealingly engage a wall of a water heater tank, the base member having a recess; a thermistor positioned in the recess; members connected to the thermistor and extending outwardly of the base member to transmit temperature information; a sheathing sealed to and extending outwardly from the base member; a heating coil positioned within the sheathing; cold pins connected to opposed ends of the heating coil and to the base member, the cold pins being sufficiently long that heat generated by the heating coil is not detected by the thermistor; and members connected to the cold pins and extending outwardly of the base member to transmit power to the heating coil.

Abstract: A method and an apparatus for detecting the crack of a heater of an acid and rinse bath, acid and rinse bath is filled with acid solution, a heater is used to heat the acid solution. A heater is constituted of a hollow quartz tube with one closed end and one open end, the closed end is submerged into acid solution, part of the quartz tube is exposure in the air. The heated filament is inserted into the open end of the heater through the closed end of the heater, moisture detecting device is attached on the inner side wall of the quartz tube, use chemicals that will change color by absorbing moisture, or use electronic component to detect the humidity, monitoring the variation of moisture in the quartz tube to acknowledge is there any crack of the quartz tube, and replace the defect quartz tube before too late.

Abstract: A water heater includes: a reservoir having a feed pipe protruding inwardly into the reservoir for directing cold water into the reservoir; a main heater having a main thermostat sensor juxtapositionally secured in an immersion pipe section of the feed pipe inserted in the reservoir and a main electric heater electrically connected with the main thermostat sensor through a controller connected to a power source, whereby upon sensing of a preset high temperature by the main thermostat sensor, the main electric heater will be actuated to heat the water fed into the reservoir to the preset high temperature; and at least an auxiliary heater having an auxiliary thermostat sensor mounted in an outer pipe section of the feed pipe outside the reservoir and an auxiliary electric heater electrically connected with the auxiliary thermostat sensor, whereby upon sensing of a preset low temperature by the auxiliary sensor outside the reservoir, the auxiliary electric heater will also be actuated to heat the water in the re

Abstract: A screwplug type water heater (10) has a heating element (12) immersible in a water heater tank (T) to heat water (L). Electrical terminals (28) on the outer end of the heater connect the heating element into a heater circuit (H) for a control unit (14). The control unit also includes a sensing circuit (S) for the unit to be responsive to water temperature inputs to turn-on the heater to heat water to a desired temperature and maintain it there. A thermistor (16) provides a temperature input to the control circuit. The thermistor is encapsulated in a bracket (32) mounted in, or integrally formed with, the screwplug to sense water temperature. Terminals (36) on the outer end of the heater allow the thermistor to be connected into the control circuit.

Abstract: An electronic heater structure includes a tube body, a heating wire disposed on the bottom of the interior of the tube body and a temperature controlling circuit. The temperature controlling circuit employs a thermosensitive resistor for detecting the temperature and controlling the activation time of the heating wire. The temperature controlling circuit employs a relay for controlling whether the heating wire is powered on or off. An upper cap of the tube body is integrally formed with a projecting chamber for placing a thermosensitive resistor therein. The relay and the thermosensitive resistor are isolated from each other by a circuit board. The tube body is vacuumized to remove the thermoconductive medium therein. Except for the heating wire, the temperature controlling circuit itself will not generate high heat and emit electro-magnetic interference and the detection portion with the thermosensitive resistor can extend into the water to accurately detect the water temperature.

Abstract: A heating assembly for imparting energy to a liquid which is enclosed in a vessel, is described and which includes a base plate borne by the vessel and having a first portion which has a given first mass, and a second portion which is made integral with the first portion and which has a given second mass; a heating element borne by the second portion of the base plate and disposed in heat emitting relation relative to the liquid in the vessel; and a temperature sensor mounted in heat sensing relation relative to the second portion of the base plate.

Abstract: An electric power distribution system that utilises radio signals from the power distributor to an appliance such as a water heater 1, to inform via a receiver 12, a micro processor 10 of the energy priority rating of the power distributor. The water heater has an array of temperature sensors 5 that determines the average temperature of the tank and enables the microprocessor 10 to generate an energy needs rating for the water heater. The microprocessor is programmed with a decision algorithm that uses the needs and priority ratings to either switch the appliance on or off.

Abstract: An immersion heater has a support plate on which there is provided an electrical heating element in the form of a printed circuit conductive track. The element is provided with a portion which allows it to be clamped in direct relation to a control unit in order to provide direct electrical, thermal, and mechanical connection to that unit. This allows the control unit to operate in the same manner as a control unit connected to a conventional immersion heater. A water heating vessel using the immersion heater mounted to a control unit through an aperture in the base of the vessel is also described.

Abstract: A water heating appliance for use in a hottub or spa with said appliance consisting of an especially designed float-body with a safety shield which protrudes from the bottom of the body and also acts as a heating chamber, with an especially designed float as differs from the float-body that activates and deactivates an on/off switch but is not a part of said switch which allows the flow of electricity to a preset temperature shut-off switch that lets electricity flow to a heating element where it is changed into heat and heats the water in the heating chamber until the temperature sensor of the shut-off switch senses a preset temperature and stops the flow of electricity by opening a circuit in said switch keeping the water from getting too hot and avoids scalding of the user of the hottub or spa.

Abstract: An underwater heater for warming water in an aquarium comprises a thermal sensor for sensing temperature of a main heater body and a control unit for controlling operation of the main heater body via reception of a detect signal output from the thermal sensor. In addition to a switch device for opening and closing a power-supply circuit for supplying power to the main heater body, the control unit further comprises a drive circuit, an abnormality-detection circuit, and a memory circuit. Whenever the abnormality-detection circuit detects that the thermal sensor has detected an abnormal temperature, the drive circuit activates the switch device to open itself to cause power supply to the main heater body to be shut off and to simultaneously cause the memory circuit to store the abnormality-detected condition therein.

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: 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: A temperature control heater with sink type glass tube liquid crystal (LCD) display, especially relates to a temperature control heater having a structure for display the temperature precisely, the mainly structure thereof is comprised of a single opening tube, and a liquid crystal (LCD) display temperature control circuit board and a heating coil set is arranged with said tube, finally a plug and a cover are used to tightly seal the tube.

Abstract: A jet bath designed to use minimum water, to use a formed in place low cost waterfall type water inlet, to have pulsating and massaging air-water jets appropriately located in the tub, to allow user adjustment of water temperature, to prevent heating the water above 122 degrees Fahrenheit and prevent tripping of a manually resettable high temperature limit switch with initial filling of the tub with overheated water.

Abstract: An immersion heater has a support plate on which there is provided an electrical heating element in the form of a printed circuit conductive track. The element is provided with a portion which allows it to be clamped in direct relation to a control unit in order to provide direct electrical, thermal, and mechanical connection to that unit. This allows the control unit to operate in the same manner as a control unit connected to a conventional immersion heater. A water heating vessel using the immersion heater mounted to a control unit through an aperture in the base of the vessel is also disclosed.

Abstract: A device for heating the water in an aquarium comprises a casing, and housed in the casing, at least one heater element, a thermostat, an electrical circuit by way of which the heater element and thermostat are wired in series to an external power supply, and a control facility for regulating the heater element, which is connected to the thermostat and can be activated from externally of the device; the operation of the heater element is indicated by a lamp. The casing affords at least one internal cavity consisting in a tubular glass wall around which the heater element is wrapped, and having open ends so that the water can pass through.

Abstract: A continuous boiling water unit is disclosed and comprises a water heating tank (1) containing an electric heating element (2) near the bottom of the tank (1) and a level control tank (3) mounted alongside the heating tank (1). An interconnecting steam communication port (21) is located between the level control tank (3) and the heating tank (1), together with a draw-off connection (23) and a flow connection (10). There further comprises an electronic temperature sensor in the form of a thermister (50) operable to sense the temperature of water in the heating tank (1), and upon sensing boiling of the water in the heating tank (1), operable to cause cut-off of the supply to the heating element (2).

Abstract: A secondary air supplying apparatus for an internal combustion engine and a gas heating apparatus are provided to enable high-performance exhaust gas purification in a catalytic apparatus of the internal combustion engine, in particular, even at a low-temperature starting time. A secondary air supplying apparatus supplies secondary air to the catalytic apparatus through a secondary air introducing path for communicating the intake side of the internal combustion engine with an exhaust manifold. In the apparatus, a gas heating apparatus having an exothermic body is provided for the secondary air introducing path.

Abstract: An electronic immersion heater includes a tube closed at one end that contains in succession from its bottom to its open end: a heating element, an electronic circuit board with the corresponding support and with a temperature sensor, and a hermetic plug. The electronic heater is characterized in that the sensor is pushed into direct or indirect contact with the tube by means of a single helical spring, which furthermore simultaneously acts as a spacer and as an electrical contact, without conventional rheophores, between the temperature sensor and the electronic circuit board.

Abstract: An immersion heater includes a heating element having a return portion around which is wrapped a thermally conductive link. The link extends through a plastic head and seal member, by which the element is mounted in an opening in a wall of a heating chamber, and has a first portion bent down to cooperate with a bimetallic actuator of a thermally responsive control, which operates in the event that the element overheats. A second portion of the link is bent upwardly, its upper end cooperating with a thermally deformable member of the control which, in the event that the actuator fails to operate, will deform so as to disconnect the power supply to the element.

Abstract: An electric heating assembly for use with an electric kettle or similar liquid heating apparatus has a resistance heating wire disposed within a metal sheath and connected to pins which project from respective ends of the sheath. A temperature sensitive cut-out device is connected in thermal transfer relationship to a sleeve or liner of thermally conductive material which is fitted into the element sheath at one end thereof in thermal transfer relationship with the inner surface of the sheath. The sleeve or liner extends into the sheath a sufficient distance to surround a heated portion of the resistance heating wire adjacent its connection to the inner end of the respective pin.

Abstract: A combined heating element and thermostat for use in a water heater. An electrical heating element includes a U-shaped rod having first and second legs, the first leg being longer than the second. A plug fits in a sidewall of the heater. The rod is installed in the plug. The outer end of the legs are inserted in the plug. A thermostat is also mounted in the plug. An electrical terminal is attached to the plug and includes a first terminal contacting the outer end of the first leg of the rod. A second terminal contacts the other leg of the rod. A switch connects and disconnects the second terminal with the second leg of the rod. The switch is movable by the thermostat and includes a bumper element. The thermostat moves the bumper to disconnect the rod leg from the terminal when the water is heated to a desired temperature.

Abstract: An aquarium safety heater includes an adjusting screw rotatably held in a packing plug which is sealably secured in an upper portion of glass tube. A heating coil, a thermostat, a bimetal circuit breaker, and an electric controller are mounted within the glass tube. The adjusting screw is adjustable from the exterior of the glass tube for adjusting the electric contact pressure of the bimetal for ensuring reliable operation of the circuit breaker and the electric controller for safely switching off the power supply to the heating coil once the thermostat is out of order, thereby preventing the killing of fish raised in the aquarium.

Abstract: An electric immersion water heater comprises a vessel with a heating element having cold tail ends extending individually through a side wall of the vessel. Temperature sensing elements sense temperature levels of an outer wall of the heating element outwardly of the vessel and are arranged to disconnect power to the element upon either a boil condition within the vessel occurring or upon sensing an elevated temperature indicative of dry or partially dry operation within the vessel. The heating element further including a jacket defining a space around the outer wall of a core part of the heating element within the vessel adjacent the vessel wall and arranged to fill with steam upon a boil condition occurring in the vessel during normal operation.

Abstract: A control system for a beverage brewing apparatus which includes a programmable control module and a separate input device. The control system is used with a beverage brewing apparatus of the type having an infusion assembly for retaining and filtering a brewing substance, a heated water source and a water distribution system for transporting water from the heated water source to the infusion assembly. The programmable control module controls numerous adjustable functions associated with the brewer and stores at least one function limit for each of the functions which it controls. The separate input device is selectively attachable to the control module for manipulating the function limits of the programmable function retained and controlled by the control module. Function controls are associated with the input device for selecting a function to manipulate and for incrementing and decrementing the limit or limits of the selected function.

Abstract: A beverage brewing apparatus which includes a heated water reservoir, a heating element retained in the reservoir, and a thermostatic and a low water sensor configuration positioned in a heat exchange relationship with the heated water reservoir. The thermostatic and low water sensing configurations position the temperature sensors outside of the water reservoir to prevent the heated accumulation of mineral and other deposits thereon. A niche is formed in the wall of the heated water reservoir for receiving the thermostatic sensor configuration. A retaining cover is positioned over the niche to enclose the thermostatic sensor configuration in the niche. A portion of the niche against which the sensors are positioned is thinned in order to more accurately read the corresponding temperatures.

Abstract: The boiling water washing machine provides a safety control device for a heater. The safety control device comprises a metal bracket sealingly mounted on a tub. On the top of the bracket the heater is contactedly mounted. On the inner of the bracket the thermistor is installed for initially detecting the temperature of the heater, and the thermostat is installed for controlling the heater when the thermistor cannot operate properly. At the brim of the metal bracket a fuse assembly is mounted. The fuse cuts off the electrical supply when excessive heat is transmitted through the metal bracket.

Abstract: To provide a balanced supply of distilled water and undistilled hot water for a household, a condenser coil communicates at one end with a steam generator located above a hot water heater and at its other end well the holding tank of a distilled water system, with a condenser entering the hot water heater near the bottom. The steam generator power input matches the power needed to meet the recovery rate to satisfy undistilled hot water demand under normal conditions. The condenser includes a plurality of loops grouped together so a line drawn from top to bottom through them is no longer than 5 inches. The length of the loops is at least 6 inches and the tubes have inside diameters between 1/4 inch and 5 inches and a total area of at least 25 square inches. Near the outlet of the condenser, the tube bends upwardly by approximately a diameter to create a water holding portion in the lower most loop of the condenser to restrain condensate and maximize heat transfer.

Abstract: An electric immersion heater (10) is provided for heating fluids, such as water in a livestock watering tank. The electric heater includes a heater subassembly (26), a protective cover (39), and a power cord (21) having a power plug (24). The heater subassembly (26) includes a heating element (14) having first and second ends (16A and 16B) and a molded metallic case (12 or 12A) enclosing the heating element (14). The protective cover (39) encloses and hermetically seals the operative connection of a thermostatic switch (18), the first and second ends (16A and 16B) of the heating element (14), and first, second, and third conductors (22A-22C) of the power cord (21). The thermostatic switch (18) is bonded in heat-receiving proximity to the molded case (12 or 12A). Potting compound (38) disposed intermediate of the thermostatic switch (18) and the fluid to be heated is provided as a thermal barrier for restricting the heat flow from the fluid to the thermostatic switch (18).

Abstract: A water heater having a non-metallic tank and a surface mounted thermostat is provided with a thermostat mounting which reliably sensing water temperature. The thermostat mounting includes a large area plate in contact with the tank over a large area and fixed to the tank reinforcing fiberglass rovings.

Abstract: A fluid heater and storage device for a bidet includes an electric heater (3) positioned inside a housing (1) in a lower portion thereof. The housing (1) has a connection side with an inlet opening (6) and an outlet opening (7) for the fluid to enter and exit the housing located in an upper portion of the connection side. An insert (10) is positioned in the upper portion the housing (1) adjacent to the inlet opening (6). The insert (10) receives input fluid from the inlet opening (6) and guides the fluid along the connection side towards the lower portion of the housing (1). The input fluid then flows across the bottom of the housing and is heated by the heater (3) as it flows the recross.

Abstract: An advance warning control system for controlling the liquid level in a heating tank including an electrical immersion heater to provide a source of radiant energy, a control means operably associated with the immersion heater and the control means including a first normally open bi-metallic switch and a second normally closed bi-metallic switch which together operate to provide an advance warning upon energization of the first switch to give a predetermined time interval before energization of the second switch.

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: An aquarium heater includes a heating coil and a thermostat formed in a glass tube, a thermo-sensitive resistor distantly connected to the thermostat for ensuring a reliable sensing of water temperature in the aquarium without being thermally influenced by the heating coil, and a thermal type circuit breaker provided in a circuit of the thermostat and the heating coil for safely switching off a power supply to the heating coil once the thermostat is out of order to prevent killing of fishes raised in the aquarium.

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: An elongate hollow tubular assembly mounts a temperature sensing element in a reservoir to determine the temperature of a liquid in the reservoir. The tubular assembly includes an inner tubular member constructed of a thin, light-weight, electrically insulating and thermally conducting material, an intermediate tubular member constructed of a thin, heat-sealable, dielectric material, having an end thereof which extends into the reservoir heat-sealed; and an outer tubular member constructed of a moldable, water-impervious, heat-resistant and durable material. A sealing arrangement is provided for sealing an end of the outer tubular member which extends into the reservoir.