Abstract: Individual electrically heated mats, self-regulated by use of an electrical element whose resistance varies proportionately with its temperature, used for covering walking areas to prevent accumulation of snow and ice. Each mat is provided with male and female electrical connections on the ends of short power cords to permit any number of mats to be chained together in electrical parallel and to be used to cover, for example, a flight of stairs by positioning one mat on each stair.

Abstract: An underfloor heating system includes structure defining vertically adjacent upper and lower communicating cavities beneath the floor of a room to be heated. A noncombustible heat source is provided in the lower cavity. Barriers are arranged in both cavities to define communicating compartments therein. The heat source includes an arrangement for directing hot air produced thereby through the compartments in the lower cavity. The cavities communicate such that hot air passes first through the lower cavity compartments, then through the upper cavity compartments, and back to the heat source.

Abstract: A floor heating panel made of wood, a heating element on the top of the wood, a covering layer placed over the heating element to cover the entire top surface of the wood, and a cushioning layer beneath the wood. The wood has on its bottom surface a row of slits to allow the wood to resiliently flex to a limited extent. The floor heating panel has two connectors that are slidably along one dimension of the heating panel between inner and outer stop elements.

Abstract: A frost control system for a freezer door which has a header disposed along the top of a doorway for supporting a downwardly depending curtain configured for movement between a closed, extended position and an open, retracted position. Heating elements are secured to the header to inhibit frost formation on the header. In an alternate embodiment, a heat lamp is disposed on the "warm" side of the curtain proximate the doorway for directing radiant heat at the curtain to thereby inhibit the formation of frost thereon.

Abstract: Self-supporting raised floor plates of flat construction, with an outside wrapper consisting of a flat metal shell which is open at the top for a mineral, age-hardenable filler material, for instance anhydrite, are known. However, with such raised floor plates of flat construction, the embedding of an electric heating line in the layer of mineral material so that the heating line is found without interference in the statically neutral zone of the raised floor plate is problematic. The invention overcomes this problem in that the heating line is fastened to holders arranged over the bottom of the shell. These holders are fastened by clamping by means of a plug-like member in selected anchoring openings in the bottom of the shell. The heating line is clipped or respectively snapped into slots in the head segments of the holders.

Abstract: An electrical de-icer device comprises a grid-like mat with a pattern of vertical perforations extending therethrough, and including a horizontal pathway of hollow metal tubing in which an electrical heating element is located. The mat also includes metal heat conducting members (14) in contact with the metal tubing so that heat from the wiring can be conducted uniformly throughout the mat.

Abstract: An indirect heating apparatus placement under floor or wall surfaces in which the heat is generated in one direction into the room to be heated and includes simplified insulation elements having clamping type connections which are removably attached to the heating coils, and can be adapted for unlimited varieties of room shapes and sizes. The heating coil is surrounded by high insulating material except for the surface facing the room to be heated. Consequently, indirect radiant heat can be projected in essentially one direction.

Abstract: For reducing the energy required for lighting and heating in a room (2) of a building (1), windows (4) and opaque wall parts (3) of the outside wall are designed so that their heat transfer numbers (k.sub.F and k.sub.W, respectively) are smaller than 1 W/m.sup.2 K. Electric lighting fixtures (7) and heaters (8) which have at least approximately equal power ratings are used for lighting and heating.

Abstract: A method of curing green concrete using electric heating elements that are pulsed on and off by a programmable controller that controls a power source wired to an electric power main. A temperature probe may be used to inform the programmable computer of the concrete's temperature.

Abstract: A self-regulating heat producing strip is disposed along each wall of a room. The strip includes at least one pair of spaced apart electrical conductors extending longitudinally along the base of at least one wall and spaced therefrom. Self-limiting conductive material is in physical contact with and forms a heat generating zone between the conductors. An electrically insulated jacket longitudinally covers the conductors and the self-limiting conductive material. Connectors are provided for connecting the conductors to a power source to generate heat in the heat generating zone between the conductors.

Abstract: An electric radiant heating system for heating building interior living and working space. The system comprises an electric resistance heating cable embedded in a cementitious thermal mass for transferring thermal energy to the thermal mass when an electric current is applied to the cable. The system utilizes a wall-mountable line voltage thermostat control to detect the temperature of the surrounding air, compare it to a selectable reference temperature, and perform a number of functions automatically depending on the results of the temperature comparison. High limit sensors, composed of bimetal strips, detect the temperature of the electric heating cable, sending a signal to the control means to interrupt power to the electric heating system when the electric resistance heating cable reaches a predetermined temperature. Cable-retaining hardware secures the electric resistance heating cable at regularly spaced intervals to the subfloor.

Abstract: A frost resistant, horizontal folding door for a freezer room has heater assemblies in the header, jambs and for simultaneously heating the door curtain and the floor of the doorway. The heater assembly in the header can be a mat of open mesh fiber glass having a serpentine array of an electric resistance heating wire bonded to it. The heater assembly in the jamb can be a formable electrical resistance heater within the structure of the jamb. The heater assembly, for the door curtain and the floor of the doorway can be an electrical radiant heater disposed on the header and directed at the curtain and the floor.

Abstract: A compound covering element for wall, ceiling or floor linings includes a ceramic tile provided with an electrically conductive coating on its back side which is heatable to thereby heat the tile. An electrically conductive coating on the visible side of the ceramic tile dissipates static electricity.

Abstract: An electrical space heating element having a ceramic body which is provided on the side facing away from the space to be heated with an electrically resistive coating. The space heating element provides a high thermal yield while consuming little electrical power and may be used as an element of design for the periphery of a room. The space heating element may be installed in such a way so that no channels are formed which might force air currents to circulate in the room to be heated. The electrically resistive coating is a layer of a carrier impregnated with nonmetallic particles which have a large specific area, are electrically conductive, and do not substantially vary the electrical conductivity at higher temperatures. The carrier in which the nonmetallic particles are embedded has no greater than poor electrical conductivity. The electrically resistive coating is applied in such a way that it has uniform electrical and thermal conductivity.

Abstract: The invention is a window for transmitting infrared radiation for use with infrared systems, such as an infrared laser. In detail, the window comprises a polycrystalline silicon substrate doped with between 1.times.10.sup.14 and 1.times.10.sup.16 atoms per cubic centimeter of an n-type impurity. The impurities can be selected from the group consisting of Phosphorus, Arsenic, Antimony, Bismouth and Lithium. To reduce reflection, both sides of the sheet are coated with an antireflection coating. Sheet resistances of less than 25 ohms per square are obtainable while simultaneously providing excellent transmission in the infrared at both room and elevated temperatures. The internal heating produced by coupling the window to a source of electrical power can be used for deicing.

Abstract: A closed type heating apparatus including a base plate to be placed on a floor or a bed, a space defining member having supports in the form of a pillar; a straight wall or a curved wall and an upper plate having a number of openings formed therein; and a heat conducting top plate placed on the upper plate. By combining different kinds of supports, there is formed a desired air passage within a closed space formed by the base plate and the upper plate. A heater unit including a ceramic heater and a blower is arranged in the air passage to generate a heated air stream such that the heating apparatus produces a desired temperature distribution.

Abstract: A thermal walkway brick has a heating element embedded therein and electrically connected at each end to couplers mounted to opposite sides of the brick. One of the couplers is a female element that defines a channel and the other coupler is a male element having a tongue. The female element is constructed and oriented to receive the tongue of the male element of a brick of the same construction with the bricks arranged in side-by-side spaced relationship. A set of bricks is laid together to form a thermal walkway with the heating elements of adjacent bricks electrically coupled in series circuit by the couplers. The spaces between adjacent bricks are filled with mortar to complete the walkway and encapsulate the couplers. The bricks are heated by the heating elements upon application of voltage to prevent a buildup or to melt ice and snow on the walkway.

Abstract: A garage door opener heater for use on garage doors to heat the drive track of the opener during cold weather to prevent binding and restricted movement of the track when the lubricates within the track solidify at cold temperatures.

Abstract: A multiple-function electric dryer includes a casing having a nozzle extending outwardly through opening formed in the front and bottom walls thereof and arranged for upward and downward angular movement about a horizontal axis within the confines of the nozzle opening, with the nozzle being in communication with a horizontal-pipe portion of a hot air supplier within the casing. The horizontal-pipe portion has an electric heating coil therein and is provided with an air fan on an air inlet hood communicating with a casing air inlet. A retractable horizontal grating mounted for vertical movement below the bottom wall provides for laying thereon of clothing or towels to be dried by air discharged from the nozzle when downwardly positioned. The grating has a central recess portion to accomodate downward angular movement of the nozzle and is adjustably positionable by a pair of vertical rods extending into the casing.

Abstract: Webs for reducing bending in board-shaped construction elements when in use have their main direction of load perpendicular to the board plane. The devices have a sandwich of at least one first material layer, one second material layer, and one third material layer. The third material layer lies between the other two material layers and has a substantially higher coefficient of heat expansion than the other two material layers, so as to set up contracting biasing forces in the third material layer. The third material is made of a sheet metal strip. The two other materials are made of thermosetting plastic, which sets at a temperature considerably above the working temperature of the construction element.

Abstract: A collapsible sauna box is disclosed, which comprises a collapsible box body consisting of front and rear wall members, inwardly foldable left and right side wall members and a ceiling member provided at one end and heaters pivoted for angle adjustment to brackets capable of being mounted inside the collapsible box body at corners thereof. The side wall members, ceiling member and heaters are completely confined between the front and rear wall members overlapped over each other when the collapsible box body is in a collapsed state. In its collapsed state, the collapsible sauna box can be conveniently carried and stored. The heaters are not obstructive in the sauna box in use and can irradiate the user with far-infrared rays in a face-to-face relation to each other on the opposite sides of the user.

Abstract: The roof de-icing panel comprises a relatively thin metal sheet having a plurality of spaced, substantially parallel channels formed in the bottom planar surface in which electrical heating cables are disposed. The de-icing panel has an integral gutter guard portion which overlies a gutter secured to the drip edge portion of the roof. The channels form juxtaposed raised portions extending above the top planar surface of the sheet to form dams or barriers to the upward flow of water along the top planar surface.

Abstract: A wall, floor or ceiling heater comprises a plurality of self regulating, preferably PTC conductive polymer, heater elements each of which is connected to two or more connection elements. The elements are held by a support. In a preferred embodiment the heater elements are positioned parallel to each other, and perpendicular to the connection elements. The support is preferably made from a rigid material which is hinged to allow the heater to be folded or rolled for easy transport.

Abstract: A device and method for covering pilings of piers and the like includes a plastic cover or sheet which is wrapped around the piling for protecting the piling against rot, weather and wear. The plastic sheet ends overlap as they wrap around the pile. The ends are sealed and secured by a heatable strip extending between the overlapped ends of the sheet and which forms a fused plastic seam between the overlapped ends as the sheet is held tightly about the pile. A strap and a bar which presses over the heatable strip is provided for temporarily cinching the plastic sheet tightly about the pile and holding it while the heat fusing occurs.

Abstract: An electric heating element includes a core of electrically conductive material connected to a source of alternating current and has a shell of impermeable concrete. The core is moulded from a mixture of graphite powder, silicate of potassium, cement and water.

Abstract: A road heating installation which is supplied by heat stored in the ground and which includes heat pipes placed heat-conductingly with the road surface, is provided with sensors for detecting the climate factors relevant for the road condition and is equipped with a control apparatus that controls the heating installation as a function of the climate. In order to remove the heat energy stored in the ground only in case of need and to avoid the unnecessary exhaustion thereof, the invention provides that the heat transfer capacity of the heat pipe is controllable by a reversible blocking of the condensation zones of the heat pipes and the blocking is brought about in case of a dry-cold by the supply of an inert gas into the condensation zones of the heat pipes which is quantity-regulatable directly from the outside.

Abstract: A self-regulating heat producing strip is disposed along each wall of a room. The strip includes at least one pair of spaced apart electrical conductors extending longitudinally along the base of at least one wall and spaced therefrom. Self-limiting conductive material is in physical contact with and forms a heat generating zone between the conductors. An electrically insulated jacket longitudinally covers the conductors and the self-limiting conductive material. Connectors are provided for connecting the conductors to a power source to generate heat in the heat generating zone between the conductors.

Abstract: A control switch system for a railway switch heater with an environment probe near the switch and controlling switching on and off of the switch heater in a predetermined mode.

Abstract: In order for a wall, ceiling and/or floor formation comprising a substratum which may or must be plastered and a surface layer and further a flat resistance heating element arranged between the surface layer and the substratum and composed of a polyester cover layer, a conductive intermediate layer provided with lead-ins and lead-outs, e.g.

Abstract: Method and apparatus for preventing mud slides comprising determining an area of soil to which to apply heat to evaporate water accumulation therein; determining, as a function of water drainage and water accumulation, a desired rate of water evaporation to maintain rigidity of the soil; and applying the determined amount of heat to the soil thereby to prevent mud slides. A series of electrical heating units are deployed strategically in the soil, and are energized by controlled amounts of energy in accordance with the level of a feedback signal from respective sensors located in the respective heating units. Mud slides may be prevented by determining a specific pattern in the area subjected to mud slides in which to deploy a series of heating units so as to form a rigid barrier which holds in place compliant soil in proximity to the rigid barrier.

Abstract: A laminated electrical heating foil element includes electrical resistance strips embedded between two sheets of insulation material to make the laminated heating element with its power supply terminal. The heating element is in particular adapted for horizontal floor mounting between adjacent floor joists, and each element may either be wider than the specified joist distance by approximately 2h, where "h" is the specified minimum distance to be left free above an installed element, or each element may be provided with fastening devices which may cooperate with complementary catching devices on the joists. Different fastening devices between joist and heating element, as well as easy-to-fold zones running along both side edges of the heating element, are included.

Abstract: An electrical heating system for buildings is described in which the output voltage to a resistance heater is varied in accordance with outside temperature. The disclosure includes system means for compensating for solar radiation and wind effects. Also, night setback and morning start up are provided. The heat present on the interior of the building is provided in accordance with the building characteristics and without regard to interior temperatures.

Abstract: An electrical heating system for use in heating surfaces. A heating element is constructed of mesh screen comprised of small gauge wires which are spaced in a close mesh arrangement such that the total surface area of the wires is substantially equal to or greater than the adjacent area of the surface to be heated. The longitudinal wires are electrically conductive and are preferably made of a nonferrous metal and the transverse wires are coated with an insulating material. The heating element is positioned substantially parallel to and adjacent the surface to be heated. The heating system includes electronic circuitry which essentially eliminates transmission of power surges, voltage spikes and chatter when the heating system is connected to an alternating current power source. The heating system also includes protective circuits and devices for preventing injury or damage due to transformer overheating, or due to under-current or over-current conditions.

Abstract: A compact instantaneous-type electric water heater for household and commercial use provides hot water at a rate of at least five gallons per minute and includes a plurality of individual heating chambers connected in series flow relationship between a cold water inlet and a hot water outlet. A metallic mixing coil is disposed in series between each adjacent pair of chambers to promote even heating. The chambers are provided with electric heating elements having a combined wattage of at least thirty-thousand (30,000) watts. The heating elements are energized by a flow switch only at the time hot water is demanded and are controlled by an adjustable thermostat which sets the outlet water temperature and by a high temperature safety switch limiting outlet water temperature should the thermostat fail.

Abstract: A heating panel includes a fiber-reinforced mortar prepared from a mixture of a cementing material, a finely divided mineral aggregate and water and incorporating a fibrous reinforcement material homogeneously dispersed therein, and a flexible electric heating element embedded in the fiber-reinforced mortar. The heating panel of the invention can be made relatively thin while still exhibiting good flexural, compressive and tensile strength properties, thus being relatively light in weight for ease of handling and low cost transportation.

Abstract: A reservoir type electric water heating tank for containment within a void defined between the upper and lower plates, pair of spaced vertical studs and the opposing surface elements of a structural wall includes a relatively thin tank structure peripherally thermally insulated with thin rigid insulation and having a rectilinear configuration. The tank has two spaced opposed sides of substantial areal extent with vertical flutes therein to provide rigidity joined to a pair of elongate rectilinear vertical ends and horizontal top and bottom elements to define a chamber for containment of water to be heated. Structural brackets extend laterally from the upper and lower portions of the vertical ends of the tank to the peripheral surface of the thermal tank insulation and are secured by lateral extensions thereof to vertical post-like studs having laterally extending fastening brackets adapted to be secured to the plates of the structural wall.

Abstract: An electrical heating panel assembly includes a thin planar panel with a length of electrical resistance wire embedded therewithin and a pair of cold leads projecting from an edge surface. An insulated multiple conductor power line extends along the panel edge surface and has a portion of its outer insulation removed. The cold leads are connected respectively with power line conductors at the insulation free portion of the power line. A U-shaped closure member may be hinged or fixed and has thin flat leg portions which embrace the panel side surfaces adjacent the edge surface. A body portion of the closure member is spaced from the edge surface of the panel to define an open end tubular enclosure for the insulation free power line portion, the cold leads, and the connection therebetween.

Abstract: A heating cord comprises bendable electric heating wire and nonconductive fiber. A net type heater is formed from the heating cords. Common power source terminals comprising a plurality of bendable conductors are fixed at both sides of the net type heater and are connected to the electric heating wire thereof.

Abstract: A plastic sewer vent line extending through the roof of a building is provided with a defroster for preventing blockage of the vent line by freezing and the consequent back-up sewage gas into the building. The defroster is located above the roof and includes a metal pipe, e.g., of copper, having its bottom end coupled to the plastic sewer vent line and provided with an electric heating coil in contact with a portion of the exterior thereof. An outer shell is spaced outwardly from and surrounds the exterior of the pipe and has a top sealed to the pipe top and a bottom sealed to the roof to provide an annular providing an insulating effect and enhancing the effectiveness of the heating element. A heat limiting switch is provided to prevent overheating.

Abstract: An electrical heating system for use in heating surfaces. A heating element is constructed of mesh screen comprised of nonferrous, small gauge metal wires which are spaced in a cloth mesh arrangement such that the total surface area of the wires is substantially equal to or greater than the adjacent area of the surface to be heated. The heating element is positioned substantially parallel to and adjacent the surface to be heated. The heating system includes electronic circuitry which essentially eliminates transmission of power surges, voltage spikes and chatter when the heating system is connected to an alternating current power source. The heating system also includes protective circuits and devices for preventing injury or damage due to transformer overheating, or due to under-current or over-current conditions. An optional electronic circuit permits use of the device for preventing formation of ice on surfaces in an efficient and economical manner.

Abstract: Rail track heaters, comprising metal sheathed electric heaters, adapted to be positioned for heating a third rail or a switch rail. Our invention includes a simple stamping to provide a bracket for holding a cover containing the heater and surrounding insulation in position on the rail, and the same type of bracket made to be used to hold the terminal assembly of the heater in position on the rail. Each of the brackets is firmly held to the rail by a bolt extending transversely of and underneath the rail, the bolt having a hook at one end to hook over an adjoining part of the rail flange at one side of the rail, and having its other end adapted to engage a bracket part at an adjoining portion of the rail flange at the opposite side of the rail.

Abstract: A gypsum wallboard with electrical heating wire disposed in grooves arranged to minimize tendencies for the board to crack when lifted by the two opposite board ends.

Abstract: A radiant heater for heating the surrounding environment or for transferring heat therein to a remote location. In one embodiment the radiant heater comprises a plate provided with a series of interconnecting grooves in the surface thereof. Disposed in the grooves is either a wire for producing heat when an electric current is passed therethrough or a tube for conducting a fluid, the temperature of which may be greater than, equal to, or less than the temperature of the region surrounding the tube. The wire or tube may be confined within the grooves by a filter material occupying substantially the portion of the grooves not occupied by the wire or tube. In another embodiment, the radiant heater comprises a flat container for such wire or for conducting a fluid, which container is sandwiched between two plates. Several radiant heaters may be functionally interconnected.

Abstract: A device to melt ice and snow on a roof structure to provide channels for the drainage of water, the device being an elongated, rigid structure having a hinged end portion to extend over a gutter, having means in connection with the other end portion thereof to removably support the same, the device being formed of a highly conductive material having heating cables in contact with the outer structure thereof for heat transference and having a plurality of apertures in the upper surface thereof, the device being particularly designed to be installed either upon a dry roof or upon a snow or ice covered roof.

Abstract: A radiant panel type heating apparatus includes a heating element comprising a sheet of electrically conductive paper which generates heat as a result of resistance to current flow therethrough. The heating element includes spaced apart primary conductor elements comprising thin copper strips which are sewn to the conductive paper to provide uniform distribution of current flow through the paper from one conductor element to the other. The heating element is sandwiched between a main insulative panel member on one side and a heat conductive panel member one the other side to form a heat radiating surface. The heating element is secured in assembly with the panel members by strips of non-conductive and heat resistant double sided adhesive tape. The panel type heating apparatus may be provided in various geometric shapes and includes a thermal switch and fuse assembly to limit the maximum surface temperature of the heating element.

Abstract: Electrical resistance strip heating element, the insulated side areas of which are mechanically reinforced in order to render the strip less sensitive to tearing. The reinforcement may be of a slightly stretchable open mask type textile web.

Abstract: A warming room whose flexible, electric blanket-like wall or walls, floor and ceiling generate surface heat to provide uniform warmth in the area which they enclose. Portions of the warming room comprise one or more warming walls or barriers to increase the temperature of an indoor area and enhance the comfort of its occupants. Using the invention, people lower thermostat settings in portions of rooms, offices or other buildings which are not occupied while they occupy the warmer area within the warming room or adjacent to a warming barrier or enclosure made of warming barriers.

Abstract: A thermostatic control for electric cables used on overhanging eaves of pitched roofs in northern climates, and in rain gutters and downspouts, comprises a high temperature-limit switch and a low temperature-limit switch connected in series circuit for controlling energization to a narrow temperature range extending from the freezing temperature of water to several degrees colder. Above-freezing temperatures will melt ice and snow without supplemental heating, and sufficiently colder temperatures will not be raised sufficiently by heat loss through a building roof to thaw ice and snow accumulation on the roof and provide run-off water to the unheated eave, rain gutter and downspout where freezing can occur and result in the formation of an ice dam which will block drainage of further run-off water and which may grow in size to cause water to back-up and seep under roofing shingles to leak through the roof.

Abstract: A temperature control system and method for controlling the bus bar temperature of an automated guideway transit system in relation to the ambient dew point temperature. A resistance temperature device detects the temperature of the bus bars, and a dew point cell detects the dew point temperature of the ambient atmosphere. A first transmitter converts the detected bus bar temperature to a first electrical signal, and then amplifies and transmits the first electrical signal. A second transmitter converts the detected dew point temperature to a second electrical signal, and then amplifies and transmits the second electrical signal. A first electronic comparator receives the transmitted signals and detects the magnitude of the difference between the two signals. When the magnitude of the difference between the two signals reaches a set level, an output signal is triggered.

Abstract: A compound covering element for wall, ceiling or floor linings includes a ceramic tile provided with an electrically conductive coating on its back side which is heatable to thereby heat the tile. An electrically conductive coating on the visible side of the ceramic tile dissipates static electricity.