Base containing an electric heater element and an automatic temperature control for supporting glass or ceramic cookware

Claim 2

A cooking appliance for supporting and automatically controlling the temperature of a glass or ceramic cooking dish comprising: a base including a reflective surface and means for supporting said dish above said reflective surface; heater means disposed within said base and spaced below said supporting means to provide a space between said heater and the underside of said dish; means for automatically controlling the heater means in response to the temperature of said dish; said control means including a manually adjustable temperatureresponsive switch means for controlling the energization of said heater means and a housing for shielding said switch means from said heater means; said housing comprising at least a first part and a second part geNerally in non-conductive heat relationship to each other; said first part including at least a top wall having an outer surface highly absorptive to radiant thermal energy in the cooking temperature range and conductive means for transmitting the thermal energy absorbed by said outer surface to said temperature responsive switch means; and said second part including means cooperating with said first part to enclose said temperature responsive switch means within said housing.

Claim 3

An appliance according to claim 1 wherein said housing is fabricated of a generally heat conductive metal and said outer surface of said top wall is treated so as to have an emissivity factor of at least 0.95 for thermal radiation in the cooking temperature range.

Claim 4

An appliance according to claim 2 wherein said conductive means is fabricated of a heat conductive metal and wherein its surface is generally reflective so that the heat therein is not radiated therefrom, thereby maintaining a minimum heat loss in transmitting the thermal energy to said temperature responsive switch means.

Claim 5

An appliance according to claim 3 wherein said second part of said housing has inner surfaces and outer surfaces with all said surfaces treated similar to said top surface of said first part.

Claim 6

An appliance according to claim 4 wherein said treated surfaces are covered by an emissivity coating.

Claim 7

An appliance according to claim 5 wherein said emissivity coating comprises Sicon Black. outer

Claim 8

An appliance according to claim 6 wherein said housing is generally disposed within said base with said outer surface of said top wall generally adjacent the bottom surface of said cooking dish supported thereon.

Claim 9

A cooking appliance for supporting and automatically controlling the temperature of a glass or ceramic cooking dish comprising: a base including a bottom portion and means for supporting said dish above said bottom portion; heater means disposed within said base and spaced below said supporting means to provide a space between said heater and the underside of said dish; means for automatically controlling the heater means in response to the temperature of said dish; said control means including a manually adjustable temperature-responsive switch including a bi-metal arm for controlling the energization of said heater means and a housing for shielding said switch means from said heater means; said housing comprising at least a first part and a second part generally in non-conductive heat relationship to each other; said first part comprising a generally planar horizontal top wall and a generally vertical depending wall in conductive heat relationship; said second part comprising an opposing bottom wall generally adjacent the bottom of the pan and substantially vertical wall means which cooperates with the respective walls of said first part to enclose said switch; said bimetal arm of said switch being mounted on said vertical wall of said first part interiorly of said housing and in intimate conductive heat transfer relationship thereto; and said top wall having an outer surface treated to be generally highly absorptive to radiant thermal energy in the cooking temperature range; said treated surface of said housing disposed within said base to be generally adjacent the bottom surface of said dish; whereby radiant heat energy generated by said dish and incident upon said top wall is absorbed by said wall and transferred to said bi-metal to control said switch.

Claim 10

A cooking appliance for supporting and automatically controlling the temperature of a glass or ceramic cooking dish comprising: a base including a bottom portion and means for supporting said dish above said bottom portion; heater means disposed within said base and spaced below said supporting means to provide a space between said heater and the underside of said dish; means for automatically controlling the heater means in response to the temperature of said dish; said control means including a manually adjustable temperature-responsive switch including a bi-metal arm for controlling the energization of said heater means and a housing for shielding said switch means from said heater means; said housing comprising at least a first part and a second part generally in non-conductive heat relationship to each other; said first part comprising a generally planar horizontal top wall and a generally vertical depending wall in conductive heat relationship; said second part comprising an opposing bottom wall generally adjacent the bottom of the pan and substantially vertical wall means which cooperates with the respective walls of said first part to enclose said switch; said bimetal arm of said switch being mounted on said vertical wall of said first part interiorly of said housing and in intimate conductive heat transfer relationship thereto; and said top wall having an outer surface treated to be generally highly absorptive to radiant thermal energy in the cooking temperature range; said treated surface of said housing disposed within said base to be generally adjacent the bottom surface of said dish; whereby radiant heat energy generated by said dish and incident upon said top wall is absorbed by said wall and transferred to said bi-metal to control said switch.

Claim 11

A cooking appliance according to claim 8 wherein said first and second parts of said housing are fabricated from heat conductive metal and the inner surfaces of said top wall and both inner and outer surfaces of said depending wall of said first part are generally reflective to thermal radiation.

Claim 12

A cooking appliance according to claim 9 wherein the inner and outer surfaces of said walls of said second part are treated similar to said top surface of saiD first part.

Claim 13

An appliance according to claim 10 wherein said treated walls comprise an emissivity coating thereon to provide an emissivity factor of at least 0.95.