Circuit arrangement for accelerated continuous cleaning of self cleaning oven coatings

Claim 2

A continuously cleaning oven comprising an outer oven housing enclosing walls defining a bake and broil compartment, said compartment having a bottom wall, opposite side walls, a door for closing said compartment, a rear wall and a top wall, a thermal cleaning coating on the exposed surface of at least said bottom wall, and having the characteristic of oxidizing oven food soils thereon in the oven temperature range of between 400* and 600* F., a baking element supported adjacent the bottom wall and a broiling element supported adjacent the top wall of the compartment, control means for said bake and broil elements settable in a ''''cook'''' position to control said elements to effect a cooking operation including a bake operation and a broil operation and user settable in a ''''clean'''' position to control said elements to effect an accelerated thermal cleaning operation, said control means including a circuit connecting said bake and broil heating elements to a source of electrical power, an oven temperature thermostat connected in said circuit and presettable throughout an oven temperature range in said ''''cook'''' position for controlling the energization of said bake and broil elements in a cycling mode during said bake operation, and presettable in a fixed ''''broil'''' setting in said ''''cook'''' position for controlling the energization of said broil element for normally continuous operation during said broil operation but adapted to cycle said broil element at an oven temperature in excess of substantially 600* F., said thermostat including a sensor supported adjacent said top wall for sensing oven temperature thereat, said circuit including a double pole-double throw transfer switch interconnected in series electrical circuit between said thermostat and said elements for connecting said elements in said ''''cook'''' position for said cooking operation, and said transfer switch operative for connecting said elements in said ''''clean'''' position such that when said thermostat is set in said ''''broil'''' setting said circuit provides full wattage to said bake element and no wattage to said broil element whereby said bottom wall is heated to an accelerated cleaning temperature by said bake element while said thermostat functions to cycle said bake element to prevent the oven temperature at said sensor from exceeding substantially 600* F. during the accelerated thermal cleaning operation.

Claim 3

A continuously-cleaning oven as recited in claim 1 wherein the thermostat sensor is in the form of an hydraulic diaphragm bulb.

Claim 4

A continuously cleaning oven comprising an outer oven housing enclosing walls defining a bake and broil compartment, said compartment having a bottom wall, opposite side walls, a door for closing said compartment, a rear wall and a top wall, a thermal cleaning coating having the characteristic of oxidizing oven food soils thereon in the oven temperature range of between 400* and 600* F. on the exposed surface of at least said bottom wall, a baking element supported adjacent the bottom wall and a broiling element supported adjacent the top wall of the compartment, control means for said baking and broiling elements settable in a ''''cook'''' position to control said elements to effect a cooking operation including a bake operation and a broil operation and user settable in a ''''clean'''' position to control said elements to effect an accelerated thermal cleaning operation, said control means including a circuit connecting said bake and broil heating elements to a source of electrical power, an oven temperature thermostat having first and second cycling contacts connected in said circuit and presettable throughout an oven temperature range in said ''''cook'''' position for controlling the energization of said bake and broil elements in a cycling mode during said bake operation and presettable in a fixed ''''broil'''' setting in said ''''cook'''' position for controlling the energization of said broil element for normally continuous operation during said broil operation but adapted to cycle said broil element at an oven temperature in excess of substantially 600* F., said thermostat including an hydraulic sensing bulb supported adjacent said top wall for sensing oven temperature thereat, said control circuit including first and second line conductors and a neutral conductor connected to said source of power; said oven temperature thermostat having first and second cycling switches controlled by said bulb and operative with said cycling contacts so as to be responsive to temperatures in said oven compartment; said control means including a pair of interconnected transfer switches in the form of a double pole-double throw switch, first circuit means connecting said first line conductor and said first thermostat cycling contact to a junction of said broil heating element and said bake heating element, said broil heating element having its other side connected to one switch of said pair of interconnected transfer switches, said bake heating element having its other side connected to the other switch of said pair of interconnected transfer switches, second circuit means connecting said second line conductor and said second thermostat cycling switch to a junction of a first fixed thermostat bake contact and a fixed broil contact, said first fixed bake contact connected via a first movable bake contact to one ''''cook'''' contact of said transfer switch, said fixed broil contact connected via a double throw movable contact to the other ''''cook'''' contact of said transfer switch, third circuit means connecting said neutral conductor to a second fixed bake contact; said second bake contact connected via said double throw movable contact to said other ''''cook'''' contact of said transfer switch, said one ''''cook'''' contact electrically connected to an opposite ''''clean'''' contact of said transfer switch; said other ''''cook'''' contact electrically connected to an opposite ''''clean'''' contact of said transfer switch thereby connecting said heating elements in a ''''cook'''' circuit to provide alternatively full cycling power to said broil element or cycling power to said bake element and said broil element, said interconnected transfer switches operative for connecting said elements in a ''''clean'''' circuit such that when said thermostat is set in said ''''broil'''' setting said circuit provides full wattage to said bake element and no wattage to said broil element whereby said oven bottom wall is heated to an accelerated cleaning temperature while said thermostat functions to cycle said bake element to prevent the oven temperature at said sensor from exceeding substantially 600* F. during the accelerated thermal cleaning operation.

Claim 5

A continuously cleaning oven comprising an outer oven housing enclosing walls defining a bake and broil compartment, said compartment having a bottom wall, opposite side walls, a door for closing said compartment, a rear wall and a top wall, a thermal cleaning coating having the characteristic of oxidizing oven food soils thereon in the oven temperature range of between 400* and 600* F. on the exposed surface of at least said bottom wall, a baking element supported adjacent the bottom wall and a broiling element supported adjacent the top wall of the compartment, control means for said baking and broiling elements settable in a ''''cook'''' position to control said elements to effect a cooking operation including a bake operation and a broil operation and user settable in a ''''clean'''' position to control said elements to effect an accelerated thermal cleaning operation, said control means including a circuit connecting said bake and broil heating elements to a source of electrical power, an oven temperature thermostat having first and second cycling contacts connected in said circuit and presettable throughout an oven temperature range in said ''''cook'''' position for controlling the energization of said bake and broil elements in a cycling mode during said bake operation and presettable in a fixed ''''broil'''' setting in said ''''cook'''' position for controlling the energization of said broil element for normally continuous operation during said broil operation but adapted to cycle said broil element at an oven temperature in excess of substantially 600* F., said thermostat including an hydraulic sensing bulb supported adjacent said top wall for sensing oven temperature thereat, said control circuit including first and second line conductors and a neutral conductor connected to said source of power; said oven temperature thermostat having first and second cycling switches controlled by said bulb and operative with said cycling contacts so as to be responsive to temperatures in said oven compartment; said control means including a pair of interconnected transfer switches in the form of a double pole-double throw switch, first circuit means connecting said first line conductor and said first thermostat cycling contact to a junction of said broil heating element and said bake heating element, said broil heating element having its other side connected to one switch of said pair of interconnected transfer switches, said bake heating element having its other side connected to the other switch of said pair of interconnected transfer switches, second circuit means connecting said second line conductor and said second thermostat cycling switch to a junction of a first fixed thermostat bake contact and a fixed broil contact, said first fixed bake contact connected via a first movable bake contact to one ''''cook'''' contact of said transfer switch, said fixed broil contact connected via a double throw movable contact to the other ''''cook'''' contact of said transfer switch, third circuit means connecting said neutral conductor to a second fixed bake contact; said second bake contact connected via said double throw movable contact to said other ''''cook'''' contact of said transfer switch, said one ''''cook'''' contact electrically connected to an opposite ''''clean'''' contact of said transfer switch; said other ''''cook'''' contact electrically connected to an opposite ''''clean'''' contact of said transfer switch thereby connecting said heating elements in a ''''cook'''' circuit to provide alternatively full cycling power to said broil element or cycling power to said bake element and said broil element, said interconnected transfer switches operative for connecting said elements in a ''''clean'''' circuit such that when said thermostat is set in said ''''broil'''' setting said circuit provides full wattage to said bake element and no wattage to said broil element whereby said oven bottom wall is heated to an accelerated cleaning temperature while said thermostat functions to cycle said bake element to prevent the oven temperature at said sensor from exceeding substantially 600* F. during the accelerated thermal cleaning operation.