Abstract: An improved contact toaster for heating sandwich buns and other food items features a housing containing a toasting chamber with an inlet and an outlet. The toasting chamber contains a pair of conveyor belts with a heated platen positioned between them. Each conveyor belt features a platen-facing portion so that two pathways are defined. Each conveyor belt also features a heat-distributing surface. Two auxiliary heaters are positioned so that one of each heats one of each of the platen-facing portions of the conveyor belts. One of each of a pair of tensioners engages one of each of the platen-facing portions of the conveyor belts so that each pathway tapers inward to a minimum thickness and then expands outward again. As a result, food items moving through the pathways via the conveyor belts are toasted on both surfaces and also absorb heat from both the platen and the conveyor belt surfaces in a sponge-like manner as they are compressed and released.

Abstract: Disclosed are devices and processes for producing baked thin-walled shaped articles from baking or pouring mixtures which expand during the baking process. The bottom half (18) of a baking mold (16) for producing thin-walled shaped articles is accommodated in the bottom tongs section (13) of a pair of baking tongs (7) and the top half (17) of the baking mold is accommodated in the top tongs section (15) of the tongs (7). The mold halves (17, 18) and tongs sections (13, 15) are provided with stop surfaces (68c, 64d) and sealing surfaces (17a, 18a, 21a, 22a) and are in mutual contact when the baking mold (16) is closed. At least one clamp device (30, 31) is provided to press the mold halves (17, 18, 21, 22) of the closed baking mold (16) together; said clamp device forces at least the two mold halves (17, 18) of the closed baking mold (16) together with a predetermined clamping force during clamping and eliminates at least the play between them.

Abstract: A microprocessor controlled grill apparatus for simultaneous two-sided cooking of food items. The grill apparatus includes a stationary lower cooking platen, and an upper cooking platen which is raised and lowered by a unique linear actuator. This actuator provides for two distinct types and phases of movement. The upper platen is lowered from its uppermost, angled open position first by an arcing movement which rotates the rear edge of the upper platen about a slide or thrust bearing and arcs the front edge of the upper platen downward until the upper platen is substantially parallel to but raised, or floating, above the lower platen and uncooked food. Next, the linear actuator lowers the upper platen toward the food, while keeping the upper platen horizontal and parallel to the lower platen.

Abstract: A cooking grill having upper and lower cooking plates supported between first and second supports is disclosed. The upper and lower cooking plates are each hingedly connected to the supports at a rear hinge axis. The upper cooking plate may be manually tipped to a raised position. The lower cooking plate is automatically tipped downwardly to a food ejection position by means of an actuator. An ejector is provided for positively ejecting the cooked food at the end of the cooking cycle, onto a support or receiving tray, from which cooked food may be removed by hand.

Abstract: A portable electrically powered broiler including a base element connected to a source of power, and a lid element having a heating source which electrically communicates with the base element when the lid element is in position upon the base element. The base element includes selectively removable grill and pan members. In an alternate embodiment, the lid element is at least partially formed from electrically resistive tempered glass to form the heating source.

Abstract: A top side cooker includes a cooking head that is counterbalanced by a pair of gas cylinders. A lift arm couples the gas cylinders to the cooking head. A compression spring is fitted on the rod of each gas cylinder to provide a positive force at the end of the rod travel for precluding the heavy cooking head from crashing into the grill surface.

Abstract: A clamshell or two-sided cooking system utilizes an upper platen and a lower platen. The periphery of the upper platen is marked on the lower platen by a laser-etched marking. The laser-etched marking provides a wear resistent marking which withstands the scraping and scrubbing operations associated with using and cleaning the clam cooking system. The laser-etched markings are preferably comprised of a plurality of slanted lines disposed 1/16 of a inch apart.

Abstract: An apparatus for cooking or heating a material has a base formed from a thermally conductive material. The base has a floor and a wall which define a receptacle adapted to receive the material to be heated. The cooling apparatus further includes a lid, also formed of a thermally conductive material. A heat source is provided in thermal connection with the wall. A second heat source may also be provided in thermal connection with the lid. The lid is provided with a vent to permit fluids generated during use of the apparatus to escape.

Abstract: A cooking grill having upper and lower cooking plates supported between first and second supports is disclosed. The upper and lower cooking plates are each hingedly connected to the supports at a rear hinge axis. The upper cooking plate may be manually tipped to a raised position. The lower cooking plate is automatically tipped downwardly to a food ejection position by means of an actuator. An ejector is provided for positively ejecting the cooked food at the end of the cooking cycle, onto a support or receiving tray, from which cooked food may be removed by hand.

Abstract: A grain cake baking machine having an upper mold, a ring mold and a lower mold, with the upper and lower molds sliding in the ring mold and defining a mold cavity, a first drive for moving the lower mold relative to the ring mold between a vent position and an intermediate baking position, and an unload position extending to the upper end of the ring mold for discharging the cake, a second drive for moving the upper mold relative to the ring mold between a load position out of the ring mold for loading grain and unloading a cake, and a baking position within the ring mold, a third drive for loading a charge of grain into the ring mold when the upper and lower molds are in the load positions, with the first drive moving the lower mold to the load position for venting the mold cavity, and heaters for the upper and lower molds.

Abstract: A clamshell griddle is designed so that the rising, lowering and rotating motions of the platen and the setting of distance between the griddle and the platen main body can be effected automatically and in one stroke by the operation of a single motor, thereby resulting in simple structure and low price.

Abstract: Apparatus and method for forming a strand of dough from a relatively short dough body. The apparatus comprises two pressure members, respectively provided with facing first and second dough contact surfaces. The apparatus further comprises means for keeping the two dough contact surfaces spaced from each other in order to define a transforming space for the dough body between them. Furthermore, the apparatus has means for reciprocating both dough contact surfaces in relation to each other and in relation to a constant relative position of both dough contact surfaces, in a direction essentially parallel to both dough contact surfaces. In the method, the piece of dough is placed between the two contact surfaces and the contact surfaces are reciprocated in relation to each other.

Abstract: For making a cooked waffle from batter, a waffle maker comprises a pair of opposing heater grids configured to be closed together when batter is placed therebetween for cooking, and a controllable power supply with an output coupled to the grids for supplying power thereto to heat the grids. The power supply has a cooking mode wherein a high level output is supplied to the grids during a cooking cycle and a standby mode wherein a lower level output is supplied to the grids upon completion of the cooking cycle for preventing overheating of the grids. The temperature of the grids is controlled to provide optimum cooking and to prevent overheated grids between cooking cycles.

Abstract: A muffin tray made from modified crystalline polyethylene terephthalate has a plurality of baking wells with heat-transfer inhibiting bottoms, and protruding circumferential ridges to accommodate differential thermal expansion while limiting related distortion. The muffin tray is used in a baking process having a baking step using a spiral oven with a water bath therein. Hot air is directed into close surface contact with the water pool and then into cross-flow relationship with the muffin trays to effect baking of muffin batter.

Abstract: Apparatus for cooking a food product, for example a hamburger, comprises a mould assembly for cooking the hamburger. The mould assembly is formed from first and second moulds (3,3') formed on upper and lower bodies (1,2). Each mould is formed with a pair of radially opposed arcuate side wall portions (5,6). The side wall portions (5, 6) on respective moulds (3,3') are so located and dimensioned that when they are brought together they define a substantially continuous side wall. When the moulds are moved apart spaces between the side wall portions allow the hamburger to be easily removed.

Abstract: A device for preparing puffed food products from cereals such as rice wherein the cereal is subjected to pressure and heat, the device comprising a mold having a cavity defined by a wall thereabouts, an interior surface extending about the cavity, a piston moveable into and out of the cavity, there being provided a recess formed in the interior surface of the cavity wall with an insert being located within the recess. The insert permits greater tolerances in the manufacture of the device and also acts as a thermal insulator to minimize thermal changes.

Abstract: Cooking apparatus having an upper cooking platen mounted on a support arm for swinging movement between a lower cook position and a raised position. The upper platen is mounted on the support arm for limited floating movement and upper platen adjusting mechanism is provided which engages the lower platen at a plurality of spaced points and which is adjusted by a single manually operated control. Upper platen lift assist mechanism has pressurized gas cylinders arranged so that the gas cylinders do not exert substantial upward or downward force on the upper platen arm when the upper platen is in a cook position, and assist raising the upper platen when the platen support arm is lifted out of the cook position.

Abstract: A double contact grill for cooking foods, the grill comprising: top and bottom cooking plates having heating elements; a pivotal connection between the bottom cooking plate and the top cooking plate wherein the top cooking plate is moveable between a lower position adjacent to the bottom cooking plate and a raised position; and a counterbalance disposed on an opposite side of the pivotal connection from the side of the pivotal connection on which the top plate is disposed, wherein the counterbalance is of a weight and a position to provide a seating force causing the top cooking plate to seat against the bottom cooking plate when the top cooking plate is in the lowered position and wherein when the top cooking plate is in the raised position the counterbalance provides a resisting force to maintain the top cooking plate in the upright position.

Abstract: In a hinge for pivotally connecting the tongs of a pair of baking tongs, the hinge pin is rotatably mounted by means of at least one sliding surface bearing, which comprises sliding surfaces, which are in sliding contact with each other and are respectively provided on the hinge pin and on one of two members which are pivotally connected. One of said sliding surfaces comprises a sliding surface segment and is formed with openings adjoining said sliding surface segment on opposite sides thereof and with scraping edges, which are in sliding contact with the other of said sliding surfaces and define said openings and said sliding surface segment on opposite sides thereof.

Abstract: An apparatus and method for cooking a tortilla for use, e.g. as a taco shell, produces an edible wrapper, preferably having a narrow partially cooked flexible strip across the central diameter and a fully cooked firm and crispy texture adjacent the flexible area, that can be folded into the typical taco shell U-shape. Preferably, the tortilla is cooked in a microwave oven using two perforated rigid and reusable microwave energy transparent frame members between which a flat fresh uncooked tortilla is positioned. Selective microwave attenuation by a conductive screen strip means, and controlled expansion and distortion of the tortilla by the frame members provide the double textured food end product with desirable surface bubbling, blistering and delamination.

Abstract: Cooking machine and method include a mould with first and second similarly shaped end walls and a generally surrounding, continuous side wall, the three walls together defining an internal moulding volume, with the three walls being reciprocally movable relative to one another. Heating elements are provided in at least one wall or in thermal contact therewith, and a control mechanism controls at least relative movement of the walls so that at the end of a predetermined cooking cycle the end walls and the sidewall are relatively separated to retract both end walls from the moulding volume simultaneously.

Abstract: A cooking device including a upper unit having an upper grilling plate hingeably attached to a lower unit having a lower grill plate. The upper unit movable relative to the lower unit from an open position to a closed position to form an enclosed cooking chamber to cook foodstuffs. The lower grill plate includes a well to contain liquid and a heating unit for heating the well to vaporize the liquid during cooking and supply vapor to the cooking chamber.

Abstract: A cookie maker includes a housing having a lid and a base, a heat conducting element supported within the lid of the housing, a cookie pan disposed within the base of the housing, and a heating element supported within the housing and operative to heat the cookie pan. The cookie pan and the heat conducting element cooperate to define a baking cavity having a height in the range of 0.5 inches to 2 inches.

Abstract: A pizza base unit of crust has a plurality of waffle-type depressions in its upper surface that receive pizza toppings and serve to anchor such toppings on the upper surface of the pizza. In the method of forming the pizza, raw pizza dough is formed into a pizza size portion and is subjected to a first cooking step to form a crust while simultaneously providing a plurality of the waffle-like depressions in its upper surface. Pizza toppings are then placed on the upper surface of the cooked crust and in the depressions and this assembly is then subjected to a second heating step to complete the pizza for consumption. Apparatus for carrying out the method includes a hot plate with cooking areas arranged to receive raw pizza dough for cooking into a pizza crust.

Abstract: A pizza crust cooking utensil for use with a pizza crust batter to partially precook a pizza crust. The use of the utensil provides a more uniformly producible, less porous and more stable pizza crust which has better handling characteristics for home or commercial cooking, especially for cooking in a conveyor-type toaster or oven. The utensil includes two cooking plates which align to form a hollow cooking chamber in which the crust is formed as the batter is cooked. The invention is adaptable for use in a cooking appliance or a variety of ovens and has a transition region from the crust center to the rim to assure a well-defined rim and to stiffen the crust toward the rim for better handling. Channels extending between the center region to the rim area of the utensil enhance batter flow. Preferably, the generally planar center of the lower cooking plate is thicker to assure more complete, uniform and thorough cooking of the top surface of the crust.

Abstract: An electric appliance for cooking and especially toasting food products such as ham-and-cheese sandwiches has two cooking plates (1, 2) which are hinged together. Each cooking plate is formed of die-stamped sheet metal and attached to a sheet-metal support plate (15, 16) forming a reflector, an electric heating resistor (13) being placed between the support plate and the cooking plate. The support plates (15, 16) are provided on one side with elements (3, 4) for joining them together in hinged relation and on the opposite side with elements for attaching handles.

Abstract: Baking tongs for producing edible wafers from wafer dough in a wafer baking oven or an automatic wafer baking machine consist of a wafer baking mold comprising baking mold parts in respective tong parts which are moved toward each other and away from each other in order to open and close the wafer baking mold. For a rigid interlocking of the two tong parts when the wafer baking mold is closed, the tong parts are provided with cooperating closure sections. The closure section of one tong part is provided with a rigid locking pin, which protrudes from the inside surface of that closure section. The closure section of the other tong part is formed with a through opening, which constitutes a passage for the locking pin, and is provided with a hook which is engageable with the locking pin. The hook is pivoted on the outside of the closure section and has an engaging surface for engaging an engaging surface of the locking pin. The hook is provided with an actuating element for pivotally moving the hook.

Abstract: Apparatus and method for producing shaped products from granular materials, in particular food products from cereals such as rice, corn, wheat or the like, which are pressure-baked and afterwards expanded in a heatable mold defined in a fixed upper mold and a movable lower mold (punch). Preferably the mold comprises a peripheral mold element which is individually movable. Driving means are provided for actuating the movable punch which are in the form of two aligned, separately controlled hydraulic cylinders of which one cylinder defines a precise expansion and the other cylinder controls the compression in combination with separate end switch means.

Abstract: An improved removable cooking surface assembly for the upper movable heated platen of a two-sided cooking device includes a cooking surface device having a planar rigid heat-conducting metal platen with threaded studs bonded to its upper surface, the studs being aligned with bores in an upper movable heat platen, the heat-conducting plate being coated on its lower surface with a layer of non-stick synthetic coating. The coated platen is removably connected with a heated platen and extends in contiguous relation across the lower surface of the heated platen for uniform heat transfer from the heated platen to the coated platen and the food product being cooked. Following cooking of the food product, the upper platen is raised, and the food product remains on the lower grill surface because the coating of the upper surface prevents the product from sticking to the non-stick coating over the heated platen.

Abstract: The present invention provides a package suitable for microwave cooking and browning of food items, comprising a microwave susceptive mold containing at least one cavity for containing food items, and a microwave susceptive cover extending over and closing the cavities.

Abstract: A cooking apparatus has two plates which apply heat and pressure to cook an initial food material, wherein one plate is movable toward the other plate manually to close a cooking space, then is moved by a drive to apply a pressure to the food material, and is urged to an open position by a spring.

Abstract: A baker for food items such as ice cream cones or the like. The baker includes a mold and a core positioned on a stationary frame. The mold and core closely approximate the shape of the food item and include heating elements to cook batter poured into the mold cavity to form the food item.

Abstract: An omelet pan consisting of a pan having a handle, a spatula for the pan, the spatula normally resting in the pan and having a handle, the handle of the spatula being rotatably affixed to the handle of the pan so the spatula can be rotated with respect to the pan.

Abstract: An apparatus for effecting two-sided cooking of food products, such as frozen hamburger patties, is disclosed which has been configured for highly desirable efficiency, versatility, and consistency in food product preparation. The apparatus includes a housing upon which is mounted a substantially horizontal lower platen assembly, with the apparatus further including one or more upper platen assemblies each mounted on a respective pivotal support arm for movement between a lowered inactive position and a raised active position with respect to the lower platen assembly. The apparatus includes a mounting arrangement for permitting limited relative movement of each upper platen assembly with respect to its support arm, and further includes mechanisms for maintaining a predetermined minimum spacing between the upper and lower platens for avoiding undue compaction of the food products. Automatic controls effect upward movement of the upper platen for precise cooking control.

Abstract: A heated platen with a downwardly-facing surface is provided with an upwardly-accessible handle, and with coordinately height-adjustable legs, the feet of which are adapted to stand on a grill as a food product such as a hamburger patty is simultaneously cooked from below by the grill and from above by the heated platen. By preference, the downwardly-facing heated surface is covered by a replaceable non-stick surface layer in the form of polytetrafluoroethylene-impregnated glass fiber cloth. The platen preferably is heated by on-board electrical resistance heating units, controlled from an off-board control panel to which it is connected by leads from an on-board temperature sensor, and an electrical power cable.

Abstract: A device for preparing such food items as omelets, fried eggs, and other foods cooked in a fry pan, skillet, or the like, includes means for horizontally reciprocating the cooking vessel while applying heat thereto. A generally conventional fry pan is quickly, separably attachable to reciprocating means, and during the reciprocal action imparted to the fry pan, heat is applied above and below the same to complete the cooking process during the continuous application of a gentle, back and forth movement to the vessel.

Abstract: A synchronized press and method for forming bakery products. A press plate presses a portion of bakery product ingredients against a rotatable disc in a continuous motion. A conveyor belt deposits portions of the bakery product ingredients on the disc at timed intervals. A gearing mechanism synchronizes the movement of the press plate and disc so that the horizontal speed of the press plate is substantially equivalent to the angular speed of the disc. The gearing mechanism also synchronizes the deposit of bakery product ingredients on the disc.

Abstract: A compact two-sided cooking device is disclosed for use with an existing grill to permit two-sided cooking of food products, such as hamburger patties, on a relatively limited basis. The device includes a cooking assembly having an electrically-powered cooking platen which can be selectively positioned on food products on the grill for effecting accelerated two-sided cooking thereof. The present cooking device has been particularly configured for use in conjunction with, and for rocking movement on, a commercially-sized restaurant grill, and provides greatly reduced cooking times so that a customer's order can be freshly and efficiently prepared even during relatively slow business hours.

Abstract: A method of producing a cracker from a raw material such as grain such as unhulled rice, or artificial rice, composite raw material formed in a chip-shape, or the like is disclosed. It comprises steps of compressing and heating for a predetermined time the raw material already processed to some extent to advance and contained within a hermetically closed chamber defined in upper and lower baking molds heated, moving instantaneously the upper mold finely up and down to spread the raw material on a bottom surface of the lower baking mold, and in the foregoing state, compressing and heating the raw material again, and expanding instantaneously the compressed and heated raw material at a time when the upper baking mold starts moving upwardly to remove the compression, thereby shaping the material in a cracker of a desired form in a self-sustaining structure. An apparatus for carrying out the method is also disclosed.

Abstract: An easily cleaned and serviced belgian style waffle iron has a cast aluminum base provided with a hollow interior opening downwardly between support legs of the base, an electrical power source component including a housing which is removably secured within the base cavity and includes a pair of electrical conduit plug receiving receptacles, a power line for connection to a source of electrical power, electrical conduit means for electrically connecting the receptacles to the power line and fasteners for holding the housing in the base cavity, a pair of waffle grid providing members are pivotally mounted on the base by a support shaft extending between spaced journal blocks which in turn are removably mounted to the waffle iron base in such a manner to allow easy removal of the blocks, shaft and grid providing members for cleaning or servicing thereof and a pair of detachable thermostat-electrical conduit members are provided to supply electrical power from the electrical power source component to heating ele

Abstract: A precooked, frozen waffle heating apparatus including first and second metallic castings or molds having opposed confronting faces conforming to the reciprocal of a waffle pattern and contained within upper and lower portions of a housing defining a hollow chamber surrounding the upper portion of the molds. A timer is disposed externally of the housing but affixed thereto for indicating the residence time of a waffle within the molds.

Abstract: An apparatus for cooking or otherwise heating food held in a container which includes upper and lower housing portions. Heating elements are located in the respective housing portions, and the opposed inner walls of the housing portions are adapted to be moved into contact with the food container. The heating elements are positioned immediately adjacent these walls, and these elements are substantially insulated from other portions of the housing. The intimate contact between the inner walls and the associated heating elements causes the food to act as a heat sink whereby the food is rapidly heated in a highly effective manner. The apparatus is particularly useful for the cooking of frozen food located in an appropriate container. Means are provided for retaining the upper housing in spaced apart relationship with the lower housing to permit baking and similar heating.

Abstract: There is described a device for preparing food products from cereals which have been pressure-cooked and thereafter expanded, which comprises a mould comprised of a hollow heated die to which the cereals are fed, a punch cooperating with said mould to close and open the cavity thereof by sliding, at least one jack so connected to the punch as to drive same alternately in and out of the mould cavity, said jack enabling to exert through the punch a pressure on the mould while cooking the cereals, stop means for stopping temporarily the alternating movement of the punch or of a driving member therefor in a position where said punch does not exert a pressure any more on the mould and where the mould cavity is not yet open, a device for feeding cereals to be cooked and a device for discharging the product from expanded cereals thus obtained.

Abstract: An apparatus for cooking or otherwise heating food held in a container which includes upper and lower housing portions. Heating elements are located in the respective housing portions, and the opposed inner walls of the housing portions are adapted to be moved into contact with the food container. The heating elements are positioned immediately adjacent these walls, and these elements are substantially insulated from other portions of the housing. The intimate contact between the inner walls and the associated heating elements causes the food to act as a heat sink whereby the food is rapidly heated in a highly effective manner. The apparatus is particularly useful for the cooking of frozen food located in an appropriate container. Means are provided for retaining the upper housing in spaced apart relationship with the lower housing to permit baking and similar heating.

Abstract: A portable grill device of the type including a first bowl and a second bowl hingedly connected together. The bowls are movable between a closure position where the bowls overlie one another, a generally right angular use position where the second bowl is disposed substantially normal to the first bowl, and a generally horizontal use position where the first bowl and second bowl are fully opened. Novel leg bail structure is provided that offers three-legged support to both bowls when the bowls are in the horizontal use position, and that offers a support base substantially wider than the width of the first bowl when the second bowl is in the generally right angular use position relative to the first bowl. Further, the portable grill device includes novel latch structure which retains the two bowls in the generally right angular position, that latch structure cooperating with spit holder arms for restraining those spit holder arms in an elevated position over the first bowl.

Abstract: A small cooking apparatus intended for domestic use in the grilling of steaks, hamburgers and other foodstuffs consisting of a base and a cover which are hingedly connected there being mounted in each an electric heating element embedded in a block of metal such as aluminium adapted to constitute a heat sink. Associated with which is a removable cooking plate of light washable construction which is maintained in intimate contact with the heat sink so as to ensure maximum transfer of heat. The light construction of the cooking plate and the fact that they do not incorporate heating elements facilitates washing of the plates. The plates are preferably provided with insulated handles and the cover is preferably mounted so as to be capable of tilting about its mid line to accommodate foodstuffs of different thickness.

Abstract: A cooking apparatus for cooking food held in a container which includes upper and lower housing portions. Heating elements are located in the respective housing portions, and the opposed inner walls of the housing portions are adapted to be moved into contact with the food container. The heating elements are positioned immediately adjacent these walls, and these elements are substantially insulated from other portions of the housing. The intimate contact between the inner walls and the associated heating elements causes the food to act as a heat sink whereby the food is rapidly heated in a highly effective manner. The apparatus is particularly useful for the cooking of frozen food located in an appropriate container.

Abstract: Device for grilling and broiling food comprising an electrically heated lower plate member adjacent to one end of which is provided an upstanding turret element on which an upper plate member, also electrically heated, is pivotally and adjustably supported so as to perform the cooking operation without, as a consequence exerting any pressure on the food product. Further modified embodiments disclosed herein reveal various concepts for supporting the upper plate member in an adjustable manner.

Abstract: Cup-shaped shells suitable for use as hors d'oeuvres, snacks, and the like are made from leavened dough. The shells are cut from a crust of leavened dough and then shaped by dies and heated to form a concave configuration.

Abstract: The present invention provides a bag thawer 10 for thawing at least one bag of frozen liquid. Generally, the frozen bags of liquid are I.V. bags 42 containing medical solutions. The bag thawer 10 provides an upper contact plate 12 sized to contain a first quantity of heat at room temperature and a lower contact plate 14 sized to contain a second quantity of heat at room temperature. The total heat contained in the upper and lower contact plates 12, 14 is sufficient to thaw the frozen I.V. bags 42 without applying additional heat to I.V. bag 42 or rewarming contact plates 12, 14. The upper and lower contact plates 12, 14 are hinged together by a hinge 16. The upper contact plate 12 is biased by spring 36 towards the lower contact plate 14. In one alternative embodiment, a pair of heaters 116, 118 are placed in contact with the contact plates 112, 114 to maintain the contact plates 112, 114 at approximately room temperature.