Abstract: A thermal insulation liner is provided for a chromatograph oven. The liner is moulded as a single bucket-shaped component 1 from ceramic fibers, typically alumino-silicate, bound together with an inorganic binder. The heat capacity and thermal conductivity of this material are both very low. The inner layer of the oven can be rapidly cooled for fast throughput of analyses and there is low risk of hand burns when changing chromatograph columns. The inner surface is mouled as a smooth shape, assisting the flow of circulated air and thereby reducing hot spots. Thermal insulation for the injector and detector of the chromatograph are also mouled in together with entry holes and mounting points 3,4, 5,6 to enable an inexpensive, easily assembled oven and chromatograph to be produced.

Abstract: The invention relates to a masonry fireplace, particularly a baking oven, comprising: a furnace (4) in which the fuel is burnt and the bottom of which is formed by a baking grate (5), the furnace (4) being provided with an oven door (1) positioned in the front wall of the oven; an ash chest (7) positioned below the furnace (4) and provided with an ash door (2); a secondary fire chamber (10) positioned above the furnace (4) and into which a throat (9) leads from the back portion of the furnace (4); and substantially vertical cheek flues (15) extending downwards from the secondary fire chamber (10) on both sides of the oven door (1).

Abstract: An oven cavity housing for a microwave heating device, an electric toaster and the like consists of component plates which are joined together by tubular pieces provided on one of the plates to be joined together and inserted through holes in the other. These pieces have closed top ends, which are crushed so that no openings are left after the plates are joined and pieces of wire or the like will not pass through them to allow microwave energy to leak out.

Abstract: A cooking and baking device to be built in comprising an oven and a cooktop, the oven comprising: a frame, a cabinet-shaped oven unit connected with the frame and provided with a hinged door and an oven control-member connected with the frame and carrying at least one oven actuating member partly protruding from a control-panel connected with the frame, and the cooktop comprising a cooktop unit adapted to be built in a horizontal plane and cooktop control-members connected with cooktop actuating members partly protruding from the control-panel. The cooktop control-members are functionally and permanently connected with the cooktop unit and the cooktop comprises an actuating unit releasably connected with the frame, in which at least the cooktop actuating members are arranged. Preferably at least the visible part of the control-panel is a releasable front panel with recesses for the actuating members.

Abstract: A gas-fired combination steam and dry oven has an oven cavity that is heated by heat exchange from one or more fire tubes and a boiler that is located outside the oven cavity and is heated by heat exchange from one or more other fire tubes. Both the oven and boiler fire tube heat exchangers employ natural draft gas burners. The combination oven can be operated as a forced-air convection oven, a forced-flow convection oven circulating superheated steam, or a steamer circulating saturated steam. Sensors in the oven supply information to a microprocessor that controls the gas burners to maintain an oven temperature within 5.degree. F. or less. Sensors of the level of water in the boiler assure that the water level stays within predetermined limits. Tray stops keep foods and the trays containing them away from the walls of the oven to permit free circulation of air, saturated steam, or superheated steam.

Abstract: A gas-fired convection oven comprises a cooking cavity having a centrifugal fan mounted on a rear wall thereof. A vertical shroud mounted adjacent to the fan forms a narrow heat exchanging chamber within the cavity. A heat exchanger comprising a generally U-shaped hollow tube extends within the heat exchanging chamber and is provided with outwardly directed jets on the leg portions thereof. A power jet burner surrounded by a secondary air passageway conduit communicate with an inlet into the heat exchanger. Means for baffling secondary air at the inlet to the heat exchanger provides for generally balanced flow of combustion products within both legs of the heat exchanger facilitating energy efficiency in the heating of the cooking cavity.

Abstract: A joint construction for metal sheets is made by joining first and second metal sheets with the aid of a plastic working deformation. The first metal sheet is provided with first cut-up pieces to have openings therein. A portion of one end edge of the second metal sheet partly superposed on the first metal sheet is held between the openings and the first cut-up pieces and in this state it is pressed with the cut-up pieces so that the portion is pressed into the openings. The portion of the second metal sheet pressed into the openings is locked by the peripheral walls of the openings and by the cut-up piece pressing against the portion.

Abstract: This invention is directed to a method of and apparatus or device for flame switching in order to associate a flame and the energy of the flame with different and distinct energy using systems. The flame switchable gas burning device, when adapted to be mounted or attached within the oven cavity of a gas stove, provides an improved gas stove which can, within the one oven cavity, operate in the broil, bake and self-clean mode without the need for multiple burners or multiple oven cavities and without the need for manually operated baffles or dampers.

Abstract: A pyrolytic self-clean gas wall oven having a bake and broil burner wherein a baffle separates the secondary air supply for the bake burner from the broil burner primary combustion air flow path so that, when the broil burner is off, combustion products from the bake burner are prevented from recirculating back to the bake burner via the broil burner and its primary combustion air supply path. Further, the oven has fans for moving cooling air around the outside to limit the external surface temperatures. The cooling air and the combustion air have independent flow paths so that the flame characteristics are not affected. The oven may have two oven compartments each with its own bake and broil burners.

Abstract: An oven especially--but not exclusively--for baking French bread has a single loading opening which is closed by a principal door having a fill opening therein which, in turn, is closed by a series of small longitudinal, superimposed folding doors. One edge of each folding door covers the adjacent edge of the folding door immediately next to it. The small doors either pivot over an arc 180.degree. or slide laterally. The back of the oven may be equipped with a set of doors, such as the small doors. A gap separates the front edge of plates for supporting the bread and the plane of the interior side of the small doors. The plates are relatively thin, movable perforated sheets. The ends of a latch or hook-up bar may slide into supports on the stiles of the loading opening or be held in struts provided on each side of the small doors.

Abstract: A pyrolytic self-clean gas double wall oven having over and under ovens, and an exhaust manifold on top which receives combustion products from both ovens and vents them through a single front port. The flue pipe from the bottom oven runs up along the back of the upper oven and enters the manifold above the flue pipe for the upper oven. The entrance of the upper oven to the manifold is larger than the lower oven entrance and larger than the flue pipe exit from the upper oven so as to avoid putting a back pressure on the upper oven. Both ovens are encased by an air chamber through which air is forced to cool the outside surfaces of the double wall oven.

Abstract: A country cooker system including a combination brazier, barbecue, grilling and smoking arrangement comprising a cylindrical hollow body defining a cylindrical chamber stably supported by a set of four detachable legs having upper ends thereof interfitting engaging with let insert members, the cylindrical chamber defining a smoke or cooking chamber in which horizontally disposed about a lower portion therein is a grill or cooking support surface, means providing access to the chamber through a hingedly disposed smoke chamber door supported by a set of hinges along an upper element of the door, a short pipe-shaped smoke stack supportably disposed to and communicating directly with the chamber at its lower end by a circular insert member to the cylindrical chamber, a member connecting an adjustable exhaust and flue cover supportably disposed and connected at an upper end of the stack, a detachable hollow fire box mounted about the other end of the chamber and communicating directly therewith along a lower and m

Abstract: A plurality of ceramic oven tiles (36) are supported on a metal frame (10) and the frame is supported in an oven on an oven rack (38) the frame (10) has an angle construction on all four sides. The two sides and the rear comprise upstanding walls (14, 16, 18) and inwardly extending walls (22, 24, 26) on which the tiles (36) are supported. The front has a vertically depending front wall (20) and an inwardly directed wall (28) on which front portions of the tiles (36) are supported. The front wall (20) functions to stiffen the front of the frame (10), and contributes to the overall stiffness of the frame (10). It rests against the front edge (40) of the oven rack (38), and in this manner positively positions the frame (10) on the oven rack (38). Wall (20) also functions as a handle for the frame (10). The frame (10) is constructed from sections of angle metal and metal strips, secured together by spot welding or rivets, or is a one-piece casting.

Abstract: A domestic cooking appliance vent system including a first vertical vent conduit communicating with the oven, extending through a support plate, and a second vertical conduit that is located above the first conduit but horizontally offset therefrom. A horizontal adapter duct positioned in a locating area on the support plate joins the first vent conduit with the second vent conduit. The adapter duct includes a continuous side wall, a top wall forming an open bottom positioned over the first vertical duct and a top vent opening in one end of the top wall communicating with the second vertical conduit. The support area and adapter duct is dimensioned so that its position in the locating area insures that the top vent opening in the adapter duct is axially aligned with the second vertical conduit.

Abstract: An electric double oven having two self-cleaning cavities, one cavity also having microwave capability wherein forced air from a blower repels hot self-clean air from entering the waveguide. A circuit is provided for limiting the temperature of either cavity to approximately 505.degree. F. when the other cavity is above a temperature associated with self-cleaning. The circuit also limits the common microwave cavity to approximately 505.degree. F. when the blower is not functioning so that oven cavity air entering the waveguide will not present a hazard.

Abstract: A cavity and cabinet construction for a microwave oven is provided which utilizes two U-shaped members which are nested together to form the cooking cavity and the cabinet. One member forms the front, bottom and rear panels of the cooking cavity and the cabinet and the other member forms the top panel and side panels of the cavity. The second member is laterally smaller than the first member to provide a chamber within the cabinet for housing the electrical components. The two members are secured together around the front panel by a metal crimping technique which prevents distortion and marking of the front face of the front panel and are joined along a bottom and rear edge by a metal stitching technique to secure the two members together in a radiation leak-proof manner. A U-shaped channel hinge bracket is utilized to provide support for a hinged door, the door having a hinge plate which sandwiches the flange of the front panel between the hinge plate and the hinge bracket.

Abstract: Apparatus in the form of at least one cooking chamber, e.g. a cooker or an oven for building into a kitchen unit, with the cooking chamber being delimited by a generally rectangular muffle (20) having an open front face. Heater elements (41) are disposed inside the muffle and/or outside the muffle in a contiguous chamber, and a thermally insulating material (50) is moulded over the side walls of the muffle together with the contiguous chamber if present. The thermally insulating material constitutes the core of a frame for the apparatus and forms part of a structure which provides at least a portion of the outside walls of the apparatus. Moulding the insulating material directly over the cooking chamber facilitates manufacture and reduces heat losses through heat-conducting bridges.

Abstract: A control panel is provided for a household appliance which includes a clock-timer lens which is effectively sealed to the rear of the control panel assembly. The integral clock-timer lens and control panel combine to prevent the infiltration of soil into the face of the clock-timer. The assembly is simple to clean without soil particles dropping into the face of the clock-timer.

Abstract: An improved oven seal arrangement is provided comprising an elongated flexible seal having retainer and seal portions. A channel or gap is formed in one of the oven front or oven door for receiving the retainer portion and the seal portion is captured between the oven door and the oven front.

Abstract: A muffle oven for the heating of foodstuffs has a closed housing with a treatment chamber separated by a perforated partition from an air-circulating compartment which forms rear and lateral air spaces surrounding that chamber on three sides. A radial blower, driven by an external motor located at an intermediate level in the rear air space, is bracketed by an upper and a lower baffle each having two aerodynamic deflecting surfaces converging at a flow-dividing edge which cause the air discharged by the blower to spread symmetrically into the lateral air spaces after passing two sets of heating elements. The flow-dividing edges of the two baffles are relatively offset and lie on opposite sides of a vertical axial plane of the rotor so as to point toward the rotor at locations where the flow of the discharged air is essentially vertical. The heated air, after entering the treatment chamber from the sides, is returned to an axial intake of the blower.

Abstract: A broiler for cooking food products has an upper heating unit located in a spaced relationship from the food and a lower heating unit in a close heat transfer relationship with the food. The upper unit is preferably a U-shaped radiant fire tube with a gas-fired power burner mounted at one end as a heat source. Hot flue products exiting the radiant tube are directed to the lower heating unit which is preferably a heat pipe assembly with evaporator and condenser zones for a working fluid. In one form the condenser zone includes a generally flat wall portion with a cooking surface defining a set of upwardly facing grooves. In another form the condenser zone is a series of generally parallel pipes that extend under the food in a horizontal, mutually spaced relationship. A movable rack supports the food and moves it into and out of a cooking relationship with the condenser zone of the heat pipe assembly.

Abstract: A countertop oven particularly well suited for preparing convenience foods, such as frozen dinners and hot sandwiches is provided. The oven includes at least one heating and serving tray with heat resistant handles, the tray sliding into slots in the oven side-walls with the handles on the outside so that the heating and serving tray may be removed from the oven and placed directly on a table for serving. In a preferred embodiment of the invention, the oven includes two pairs of slots for receiving two heating and serving trays and includes three heating elements. This heating configuration permits cooking on the two trays in about sixty percent of the time compared to conventional countertop ovens.

Abstract: An improved cooking oven having two flat surfaces covered by an enclosure. One of the flat surfaces serves as a base on which the enclosure rests and on which both fuel to be burned and food to be cooked are placed. The second of the flat surfaces, which is substantially parallel to and positioned above the flat surface that acts as the base, serves as a baffle to control the flow of combustion products from the burning fuel through the enclosure and as an additional cooking surface. Three openings in the wall of the enclosure are provided; two of which are used for passage of food and fuel therethrough. The third opening serves as a flue and provides a path through which combustion products from the burning fuel escape from the oven.

Abstract: A secondary oven heated by restricted heat transfer from a primary oven through a common pan-roof tempered by convention flow of ambient outside air adjustably mixed with primary oven vent air controlled by a damper diverting a portion of primary oven vent air through the secondary oven with the balance thereof discharged externally.

Abstract: A gas cooking range includes a number of energy-efficient features. The range includes an oven section in which combustion air is preheated by heated discharge gases. Panels are spaced from the walls of the oven and circulation fans are included to provide exceedingly effective airflow within the oven. A gas shutoff valve automatically controls the discharge of heated gases from the oven so that heated gases are discharged only when combustion is occurring. The range also includes a compact, rotatable oven/broiler burner unit, a smoke-free drip pan, an efficient piloted ignition, flame-containing rangetop burner rings atop which pots and pans can be supported, and a small, portable oven which can be supported atop the burner rings.

Abstract: A convection oven in which vapor is circulated through the oven by a pair of counter rotating blowers positioned in the rear of the oven which draw vapor from the oven along with combustion products from a multi-section ribbon burner which has a secondary air passage between the sections and which is positioned below the oven rear wall vapor outlet region and blow the combined vapor and combustion products into the oven adjacent the top surface. The blowers generate slight negative pressure in the combustion plenum by blowing a small portion of the output of the blowers out an output vent to control the amounts of primary and secondary air supplied to the burner system.

Abstract: An oven includes an oven structure having an oven interior, an oven door for closing the oven interior, the oven door having a transparent or translucent front plate for allowing viewing of the oven interior through the oven door, and visible adjustment and display elements for setting and displaying parameters relating to the operation of the oven. The adjustment and display elements are visual elements mounted to be covered by the front plate when the oven door is closed. The front plate has light absorbing coloration or a reflective, translucent coating to allow only the visual elements and the oven interior when illuminated to be viewed therethrough.

Abstract: This invention relates to a self-cleaning plate of a metallic porous body having a three dimensional network structure and a specific surface area of at least 2,000 m.sup.2 /m.sup.3 or more, characterized by having oxidation catalyst particles uniformly distributed throughout the binder with which the framework of said porous body is coated and with which the porosities are filled, said binder being preferably any one of an alkali metal silicate, a colloidal silica, a colloidal alumina, a monobasic metal phosphate, and a silicone resin, said oxidation catalyst being preferably at least one selected from the group of metals Pt and Pd or the metal oxides of Mn, Cr, Ni, Co, Cu, and Fe.

Abstract: An accessory included in a manufacture of a kitchen gas stove for locking shut the gas burners and also the stove doors, the accessory including a hand controlled knob at a back of the stove, the knob turning a valve along a gas incoming pipe, and also turning levers connected to hooks that hook to inner sides of the oven doors and storage drawer therebelow.

Abstract: A convection flow broiler of open front configuration having an elevator-drawer carrying a food supporting and contacting griddle controllably dipped from horizontal for continuous drainage of greases therefrom, and having fixedly positioned radiant top heat to which the griddle is adjustably positioned, and held supported by weight compensator means applying substantially uniform lift regardless of elevation.

Abstract: A composite structure for a microwave oven housing having a main frame defined by top, rear and bottom surfaces and being open along the front thereof is disclosed. A partition wall is disposed in the main frame intermediate the side edges thereof for providing and separating a cooking chamber and a control compartment. A rectangular door frame is connected to front edge portions of the top and bottom surfaces of the main frame in front of the chamber for connecting an oven door thereto, the door frame defining an opening for access to the chamber. An additional feature includes a mode stirrer housing and a waveguide mounted on the top surface of the main frame above the chamber and compartment with the top surface defining openings which communicate between the compartment and waveguide and between the mode stirrer housing and chamber for transmitting a microwave signal generated in the compartment through the waveguide to the housing, and from the housing into the chamber.

Abstract: A cooking device with a microwave heater and a gas heater as well as a cooling fan for the microwave heater. A first circuit operates the microwave heater and is connected to a source of electric power through a first switching circuit. A second circuit operates the gas heater and is connected to the electric source of power through a second switching circuit, as well as a switch arranged to be operated with a gas cock. A driving circuit for the cooling fan is connected to that switch so as to be parallel with a circuit connecting in series the second circuit and the second switching circuit. The switch, furthermore, has a first contact connected to the electric source of power through the first switching circuit and has a second contact connected to the source of power without passing through the first switching circuit, while being arranged to be connected to the first contact when the gas cock is closed and to the second contact when the gas cock is opened.

Abstract: A cooking range has a pair of side panels as its main structural members. A range top, back panel, bottom member and oven frame are all secured to the side panels and a heat insulated oven shell having an open front is supported at its forward end by the oven frame and by spaced brackets engaging the back panel. Heat conductive contact between the oven shell and oven frame, between the oven frame and side panels and between inner and outer walls of the side panels is minimized by forming upstanding pads on one of each of the pairs of members and through which suitable fastening means extend. The pads are of small area and are the only portions of the members that are in direct contact.

Abstract: The specification discloses an oven with an outer oven body and an inner oven liner disposed within the body in a spaced apart relationship to provide a space between the body and the liner. Both the body and the liner include open ends facing in the same direction. A removable panel is attached to cover the space between the liner and body. A flexible gasket is clamped between the liner open end and the panel for providing support for the liner and for engaging the oven door to form a seal between the door and the liner.

Abstract: A combination microwave and gas oven, in which an object to be heated is heat-treated by microwave energy and air heated by a gas burner inside a combustion chamber and forced to be circulated by a fan. A microwave introducing port to the heating cavity is covered with a heat insulating member provided with a film which can reflect the radiant energy transferred to the direction of the microwave introducing port. To prevent the leakage of microwave from the heating cavity especially related to a shaft of the fan which is connected to a driving motor located outside the heating cavity, a choke cavity for terminating leaked microwave from said cavity is provided.

Abstract: An oven roof or wall is formed from modular panels, each of which comprises an inner fabric and an outer fabric. Each such fabric is formed with an angle iron framework and somewhat resilient tie-bars or welded at their ends to flanges of the angle irons to maintain the inner and outer frameworks in spaced disposition while minimizing heat transfer by conduction and permitting some degree of relative movement on expansion and contraction of the module components. Suitable thermal insulation is provided within the module. Panels or skins are secured to the fabric frameworks and each such skin is secured to a framework and projects laterally so as slidingly to overlie the adjacent frame member of an adjacent panel in turn to permit relative movement during expansion and contraction.

Abstract: The specification discloses an oven liner suspension assembly for rigidly suspending an oven liner, while allowing for expansion and contraction of the oven liner undergoing heating and cooling during cooking and self-cleaning operations. A pair of elongated anchor legs is secured to the rear portion of the oven liner, and each anchor leg extends a predetermined distance beyond the bottom wall of the oven liner. An L-shaped base member of each anchor leg is rigidly secured to a main base plate of the frame assembly for the oven, thereby allowing for lengthwise expansion and contraction of the oven liner. A center flange extending from the front of the oven liner is rigidly secured to a flange extending upwardly from the main base plate assembly such that the front of the oven liner is rigidly suspended above the main base plate the same predetermined distance the rear portion of the bottom wall of the oven liner is suspended above the main base plate.

Abstract: A low temperature gas-fired or electrically heated oven and warming unit for domestic purposes having a chamber enclosed by walls and a door at the front. The chamber is variable in volume, for example by being vertically extensible by having overlapping, relatively movable wall portions at the side and back and a door which automatically adjusts to the volume of the chamber for example by being of the tambour or roller shutter type. The unit can be fixed by the top section under a kitchen wall unit and extended downwards for use. Removable, lazy-tongs linkages at the sides of the unit control the extension of the chamber and are jointly operated by a single adjustment control. Shelf supports on the linkages move to alter the spacing of the shelves as the chamber volume is varied.

Abstract: An improved air circulation system for a microwave oven having an improved air inlet for delivering ambient air to the microwave energy generating device. The air inlet is defined in part by a formed portion of the cabinet providing an air channel to the front and rear of the oven for subsequent flow to the generating device. A first portion of the delivered air is conducted to the oven space while a second portion of the air is heated by heat transfer association with the magnetron structure of the generating device. The heated air is subsequently divided into two paths. In one path, the heated air is directed through a suitable outlet to exteriorly of the cabinet. In the other path, the heated air is directed through an upper cavity portion of the heating space to a rear portion of the lower oven cavity. The heated air, together with the air delivered substantially directly from the generator space to the lower cavity, is discharged through a front, upper opening of the cabinet.

Abstract: Bread oven for individual or home use. A fume vent is arranged in the roof of the oven at the opposite end from the source of heat so that the hot gases contact the roof to heat it. A by-pass passage is provided, which can be unblocked by one position of the ash pan to produce a counter-draft and thus slow down the rate of heat production. The ash pan can also be positioned so that the by-pass passage vents fumes from cinders or embers in it.

Abstract: A hot blast type oven comprising an outer casing defining a heating chamber adapted to receive foodstuff to be cooked and having a front door for opening and closing the heating chamber. A main burner serves for producing hot gases sent to the heating chamber by a blower. A gas control section including an operation handle controls the supply of gas to the main burner and to a pilot burner adjacent thereto. An electrical control section serves for controlling the main blower and an ignition device for the pilot burner. The gas control section and the electrical control section are constituted as respective units coupled together and detachably mounted for mutual operation. The control sections are operated in accordance with movement of the door such that the operation handle is locked when the door is closed and lighting of the pilot burner can be achieved only by opening the door and displacing the operation handle.

Abstract: An oven fueling system providing a chamber for food products exposed to at least one assembly of ribbon burners for heating the chamber atmosphere. An air heater is provided for transmitting pre-heated air through a conduit to a mixer aspirator leading to the header of the assembly. An oil line connects with the conduit upstream of the aspirator mixer for supplying oil to be injected into the preheated air passing through and a gas line communicates with the conduit for supplying gas to the conduit selectively with the oil line supply. Valves thus isolate both the oil line and the gas line selectively. Additionally a sensor is provided for sensing the temperature of the assembly and a control is provided for preventing the valve at the gas line from opening until a predetermined burner assembly temperature is reached. The valve for the oil line is prevented from being opened until the temperature of the chamber is such that the oil will vaporize satisfactorily.

Abstract: A barbeque oven wherein meat is suspended on a perforated food rack within an enclosed, heat retaining housing, and heat and smoke from a firebox adjacent one end of the housing is directed along the length of the housing within a tempering passageway and then up, around the meat, and along the length of the housing in the opposite direction to an exit flue fixed to the top of the housing adjacent said end of the housing. A baffle divides the housing into upper and lower portions for directing the above-described flow of smoke and heat, and insulation located intermediate the food rack and the opening connecting the firebox and the lower portion of the housing prevents direct radiation from the firebox from striking meat on the food rack. Warming closets with a flue for controlling the temperature within said warming closets are provided adjacent said end of the housing above the firebox.

Abstract: An apparatus and method for holding food and the like at desired temperature and moisture levels for an extended period of time wherein there is provided a relatively still volume of air about the food which is heated by maintaining a regulated, temperature controlled, recirculating flow of heated air in a closed passage with the air heated by a controlled heating element and recirculated by controlled air blowers about said volume of air along at least two pairs of perpendicular axes and about a major portion of the external surface area of the volume of air without a direct contact of heated air flow with the food to provide substantially uniform heating by conduction and convection. A controllable source of moisture in the form of a water pan in open communication with the heated volume of air introduces controlled quantities of moisture into the heated volume of air.

Abstract: Food temperature responsive apparatus for controlling an oven. The apparatus includes a temperature sensing thermistor which may be included in a probe adapted for insertion into food being cooked in an oven. The apparatus includes simplified and effective means, in the form of voltage dividers and comparators, for performing the functions of de-energizing the oven heating means and energizing an audible alarm when interior food temperature reaches a preset temperature, protecting against an open-circuited or a short-circuited condition in a sensing circuit which includes the thermistor, guarding against responding to transient electrical noise, and latching the oven heating means in a de-energized condition once it has been de-energized. Even though the thermistor has a non-linear resistance versus temperature characteristic, the apparatus provides a linear temperature presetting scale and includes a linear temperature presetting potentiometer.

Abstract: A self-cleaning catalytic coating for cooking oven walls comprises a mutually sintered matrix of hard catalyst particles and binder particles.The coating is preferably made by forming large hard catalyst particles, such as compressed pellets, milling them to the required size range, typically averaging above 2 microns, then incorporating them with a binder and applying the mixture to a substrate.

Abstract: A cooking and smoking apparatus for food products comprising two distinct chambers with common outer walls, and interior walls, spaced from the outer walls, containing a plurality of openings. The spaces between the walls form ducts or air passages which allow smoke and heat to rise from a lower combustion chamber and enter an upper cooking chamber through said openings in the interior walls. Adjustable dampers in the ducts control the amount of smoke and heat entering the cooking chamber, while additional dampers control the air entering the combustion chamber and combustion products being vented from the apparatus through a chimney. One or more access doors is provided in each of the combustion and cooking chambers. The cooking chamber is provided with a flush pan or the like at the bottom thereof connected to a drain pipe to permit flushing of the cooking chamber.

Abstract: Food preparation apparatus involves a heat transmitting zone and a heat source located remotely from the transmitting zone. Heat energy is transferred from the heat source to the transmitting zone by a fluid vapor which travels from the heat source to the transmitting zone, condenses upon the transmitting zone and then returns in a liquid state to the heat source.In one described embodiment of this invention, an oven is provided wherein a fluid enclosure within the oven walls confines the vapor which transfers heat energy from a central heat source to heat transmitting surfaces.

Abstract: A combination microwave and gas oven, in which an object to be heated is heat-treated by microwave energy and air heated by a gas burner inside a combustion chamber and forced to be circulated by a fan. A microwave introducing port to the heating cavity is covered with a heat insulating member provided with a film which can reflect the radiant energy transferred to the direction of the microwave introducing port. To prevent the leakage of microwave from the heating cavity especially related to a shaft of the fan which is connected to a driving motor located outside the heating cavity, a choke cavity for terminating leaked microwave from said cavity is provided.