Self-cleaning oven with temperature limiting protection system for bake and clean

Claim 2

In an oven comprising an oven liner and an access door forming an oven cooking cavity, heating means for cooking food placed within the cavity as well as for pyrolytically removing food soil from the inner wall surfaces of the oven cavity, said heating means including a heating element and electrical power supply circuitry settable for energizing said heating element at high voltage when said circuitry is set for a BAKE mode of operation and for energizing said heating element at low voltage when said circuitry is set for a CLEAN mode of operation, oven thermostat means including oven temperature responsive switch means in said circuitry in power supply relationship with said heating means for controlling said heating element below first and second predetermined temperature limits, an oven cabinet surrounding the oven liner, and insulation between said oven liner and said oven cabinet, the invention comprising overtemperature protective means for selectively protecting against temperatures in said oven cavity above either of said first and second predetermined temperature limits, said protective means including an enclosure housing a thermostatic oven temperature limiter switch in heat transfer relation with said enclosure and a supplemental heater in heat transfer relation with said limiter switch, said supplemental heater connected in shunt with said heating element to provide more heat to said limiter switch during a BAKE mode of operation when said heating element is energized at high voltage than during a CLEAN mode of operation when said heating element is energized at low voltage, said enclosure mounted in heat transfer relation with said oven cabinet to sense indirectly temperature changes within said oven cavity, and said limiter switch in said circuitry in power supply relationship with said oven temperature responsive switch means thereby to interrupt power supply to said heating element during a BAKE mode of operation when oven temperature exceeds said first predetermined temperature limit and to interrupt power supply to said heating element during a CLEAN mode of operation when oven temperature exceeds said second predetermined temperature limit.

Claim 3

In an oven comprising an oven liner and an access door forming an oven cooking cavity, heating means for cooking food placed within the cavity as well as for pyrolytically removing food soil from the inner wall surfaces of the oven cavity, said heating means including a bake heating element and electrical power supply circuitry settable for energizing said heating element at high voltage when said circuitry is set for a BAKE mode of operation and for energizing said heating element at lower voltage when said circuitry is set for a CLEAN mode of operation, oven thermostat means including oven temperature responsive switch means in said circuitry in power supply relationship with said heating means for controlling said heating element below first and second predetermined temperature limits, an inner oven cabinet surrounding the oven liner, and insulation between said oven liner and said inner oven cabinet, the invention comprising over-temperature protective means for selectively protecting against temperatures in said oven cavity above either of said first and second predetermined temperature limits, said protective means including an enclosure housing a thermostatic oven temperature limiter switch in heat transfer relation with said enclosure and a supplemental heater in heat transfer relation with said limiter switch, said supplemental heater connected in shunt with said bake heating element to provide more heat to said limiter switch during a BAKE mode of operation when said bake heating element is energized at high voltage than during a CLEAN mode of operation when said bake heating element is energized at low voltage, Said enclosure mounted in heat transfer relation with said inner oven cabinet to sense indirectly temperature changes within said oven cavity, and said limiter switch has a wide differential and is movable from closed position to open position in said circuitry while in power supply relationship with said oven temperature responsive switch means thereby to interrupt power supply to said bake heating element when said limiter switch moves to said open position during a BAKE mode of operation as oven temperature exceeds said first predetermined temperature limit and to interrupt power supply to said baking heating element when said limiter switch moves to said open position during a CLEAN mode of operation as oven temperature exceeds said second predetermined temperature limit.

Claim 4

In an oven comprising an oven liner and an access door forming an oven cooking cavity, heating means for cooking food placed within the cavity as well as for pyrolytically removing food soil from the inner wall surfaces of the oven cavity, said heating means including a bake heating element and electrical power supply circuitry settable for energizing said heating element at high voltage when said circuitry is set for a BAKE mode of operation and for energizing said heating element at lower voltage when said circuitry is set for a CLEAN mode of operation, oven thermostat means including oven temperature responsive switch means in said circuitry in power supply relationship with said heating means for controlling said heating element below first and second predetermined temperature limits, an inner oven cabinet surrounding the oven liner, and insulation between said oven liner and said inner oven cabinet, the invention comprising over-temperature protective means for selectively protecting against temperatures in said oven cavity above either of said first and second predetermined temperature limits, said protective means including an enclosure housing a thermostatic oven temperature limiter switch in heat transfer relation with said enclosure and a supplemental heater in heat transfer relation with said limiter switch, said supplemental heater connected in shunt with said bake heating element to provide more heat to said limiter switch during a BAKE mode of operation when said bake heating element is energized at high voltage than during a CLEAN mode of operation when said bake heating element is energized at low voltage, Said enclosure mounted in heat transfer relation with said inner oven cabinet to sense indirectly temperature changes within said oven cavity, and said limiter switch has a wide differential and is movable from closed position to open position in said circuitry while in power supply relationship with said oven temperature responsive switch means thereby to interrupt power supply to said bake heating element when said limiter switch moves to said open position during a BAKE mode of operation as oven temperature exceeds said first predetermined temperature limit and to interrupt power supply to said baking heating element when said limiter switch moves to said open position during a CLEAN mode of operation as oven temperature exceeds said second predetermined temperature limit.

Claim 5

The over-temperature protective means of claim 2 wherein said limiter switch is automatically resettable from its open position to its closed position and the wide differential thereof si substantially 100* F.

Claim 6

The over-temperature protective means of claim 2 wherein the supplemental heater supplies substantially 5.8 watts of heat to said limiter switch when said circuitry is set for a BAKE mode of operation.

Claim 7

An over-temperature protective means for a self-cleaning oven having a heating element and power supply circuitry settable for BAKE and CLEAN for controlling the supply of high and low power respectively to said heating element during BAKE and CLEAN and including oven temperature responsive switch means in control relationship with said heating element for supplying and interrupting power to said heating element below low and high predetermined oven temperature limits respectively when said circuitry is set for BAKE and CLEAN, said over-temperature protective means adapted to selectively protect against temperatures in said oven above said low and high predetermined temperature limits and comprising an automatically resettable thermostatic oven temperature limiter switch having a wide differential of substantially 100* F. and a supplemental heater having a rating of substantially 5.8 watts in heat transfer relation with said limiter switch, said supplemental heater adapted to be connected for operation with said heating element to provide more heat to said limiter switch during BAKE when said heating element is supplied at high power than during CLEAN when said heating element is supplied at low power, said limiter switch adapted for mounting in heat transfer relation with said oven in a manner to sense and respond indirectly to temperature changes within said oven, and said limiter switch adapted for installation in said circuitry in power supply control relationship with said oven temperature responsive switch means thereby to interrupt power supply to said heating element during BAKE when oven temperature exceeds said low predetermined temperature limit and to interrupt power supply to said heating element during CLEAN when oven temperature exceeds said high predetermined temperature limit.

Claim 8

An over-temperature protective means for a self-cleaning oven having a heating element and power supply circuitry settable for BAKE and CLEAN for controlling the supply of high and low power respectively to said heating element during BAKE and CLEAN and including oven temperature responsive switch means in control relationship with said heating element for supplying and interrupting power to said heating element below low and high predetermined oven temperature limits respectively when said circuitry is set for BAKE and CLEAN, said over-temperature protective means adapted to selectively protect against temperatures in said oven above said low and high predetermined temperature limits and comprising an automatically resettable thermostatic oven temperature limiter switch having a wide differential of substantially 100* F. and a supplemental heater having a rating of substantially 5.8 watts in heat transfer relation with said limiter switch, said supplemental heater adapted to be connected for operation with said heating element to provide more heat to said limiter switch during BAKE when said heating element is supplied at high power than during CLEAN when said heating element is supplied at low power, said limiter switch adapted for mounting in heat transfer relation with said oven in a manner to sense and respond indirectly to temperature changes within said oven, and said limiter switch adapted for installation in said circuitry in power supply control relationship with said oven temperature responsive switch means thereby to interrupt power supply to said heating element during BAKE when oven temperature exceeds said low predetermined temperature limit and to interrupt power supply to said heating element during CLEAN when oven temperature exceeds said high predetermined temperature limit.