Domestic oven with self-cleaning bottom wall

Claim 1

AN ELECTRIC OVEN COMPRISING AN OVEN BODY HAVING AN INSULATED OVEN LINER AND A FRONT-OPENING ACCESS DOOR THAT FORM AN OVEN COOKING CAVITY, HEATING MEANS FOR SAID CAVITY INCLUDING AN UPPER BROIL ELEMENT AND AN EXTERNAL FILM HEATER ON A BOTTOM WALL OF THE OVEN LINER THAT ARE ADAPTED TO BE CONNECTED TO A SOURCE OF ELECTRICAL ENERGY, SAID FILM HEATER HAVING A PLURALITY OF PARALLEL STRIPS OF CONDUCTIVE FILM EXTENDING FROM SIDE TO SIDE OF THE OVEN CAVITY WITH THE ADJACENT ENDS OF STRIPS BEING JOINED TOGETHER WITH A COMMON TERMINAL MEANS, MOST OF THE STRIPS HAVING END PORTIONS OF REDUCED WIDTHS FOR INCREASED ELECTRICAL RESISTANCE AND HIGHER WATTAGE SO AS TO GENERATE MORE HEAT AT THE SIDE PORTIONS OF THE BOTTOM WALL OF THE OVEN LINER, THE HEATER STRIPS ADJACENT THE CENTER OF THE BOTTOM WALL BEING OF GREATER EFFECTIVE RESISTANCE THAN AT THE FRONT AND BACK OF THE BOTTOM WALL SO AS TO PULL MORE CURRENT THROUGH THE FRONT AND BACK STRIPS AND COMPENSATE FOR HEAT LOSSES AROUND THE FOUR SIDES OF THE OVEN BOTTOM WALL AND OBTAIN GENERALLY UNIFORM TEMPERATURE DISTRIBUTION THROUGHOUT THE BOTTOM WALL.