Self-cleaning oven overheat safety control

Claim 2

A cooking oven of the pyrolytic self-cleaning type for carrying out both cooking operations and cleaning operations, including: an oven cavity; heating means for said oven cavity; a door for said cavity; latching and locking means for said door for effecting locking of said door during oven operations at temperatures exceeding the cooking temperature range; a circuit for controlling said heating in both a cooking operation and in a cleaning operation; thermostatically controlled switch means in said circuit responsive to oven temperatures for normally controlling said heating means in both said cooking and cleaning operations; safety switch means in said circuit having a first normal position permitting heating in said oven, and a second position interrupting heating in said oven, said safety switch means being separate from, and operable independently of, said thermostatically controlled switch means; means for operating said safety switch means from said first to said second position in response to oven temperatures exceeding normal oven cooking temperature by a predetermined degree, when said latching means is in an unlatched condition; and means For recalibrating said safety switch means, by operation of said latching means to a latched condition, to remain in said first position with oven temperatures in a heat cleaning range.

Claim 3

An oven according to claim 1 wherein: said heating means for said cavity comprises electrical heating elements; said safety switch means is series connected to said heating means; said first normal position is a closed condition of said safety switch means, and said second position is an open condition of said safety switch means.

Claim 4

An oven according to claim 1 wherein: said means for recalibrating said safety switch means comprises means for physically displacing said safety switch means in accordance with operation of said latch means to a latched condition.

Claim 5

An oven according to claim 1 wherein: said latching means includes a draw bar movable in accordance with operation of said latching means; said locking means including first differentially expansible material means movable in response to changes in oven temperature, said locking means being moved to a position obstructing movement of said draw bar in response to oven temperature exceeding normal cooking temperature by a predetermined degree; and independent differentially expansible material means for effecting the operation of said safety switch means.

Claim 6

An oven according to claim 1 wherein: said first and said independent differentially expansible material means comprise bimetallic means.

Claim 7

An oven according to claim 1 wherein: said means for recalibrating said safety switch means through operation of said latched means to a latch condition recalibrates said safety switch means to remain in said first position with oven temperatures in a heat-cleaning range and to be operated to a second position in response to oven temperatures exceeding the upper limit of the heat-cleaning temperatures by a predetermined degree.

Claim 8

A cooking oven of the pyrolytic self-cleaning type for carrying out both cooking operations and cleaning operations, including: an oven cavity; heating means for said oven cavity; a door for said cavity; latching means for latching said door; locking means for locking said door during oven operations at temperatures exceeding the cooking temperature range; a circuit for controlling said heating means in both a cooking operation and a cleaning operation; thermostatically controlled switch means in said circuit responsive to oven temperatures for normally controlling said heating means in both said cooking and cleaning operations; normally closed safety switch means in said circuit, said safety switch means being separate from, and operable independently of, said thermostatically controlled switch means; switch-operating means responsive to oven temperatures for opening said safety switch means, said safety switch means and said switch-operating means having a first condition, corresponding to said latching means being in an unlatched condition, in which said safety switch means is opened in response to an oven temperature approximating that oven temperature at which a door-locked condition is required; and means for changing the condition of said safety switch means relative to said switch-operating means, in accordance with operation of said latching means to a latched position, to maintain said safety switch means in a closed position with oven cavity temperatures exceeding those oven temperatures at which a door-locked condition is required.

Claim 9

A cooking oven of the pyrolytic self-cleaning type for carrying out both cooking operations and cleaning operations, including: an oven cavity; heating means for said oven cavity; a door for said cavity; latching means for latching said door; locking means for locking said door during oven operations at temperatures exceeding the cooking temperature range; a circuit for controlling said heating means in both a cooking operation and a cleaning operation; thermostatically controlled switch means in said circuit responsive to oven temperatures for normally controlling said heating means in both said cooking and cleaning operations; normally closed safety switch means in said circuit, said safety switch means being separate from, and operable independently of, said thermostatically controlled switch means; switch-operating means responsive to oven temperatures for opening said safety switch means, said safety switch means and said switch-operating means having a first condition, corresponding to said latching means being in an unlatched condition, in which said safety switch means is opened in response to an oven temperature approximating that oven temperature at which a door-locked condition is required; and means for changing the condition of said safety switch means relative to said switch-operating means, in accordance with operation of said latching means to a latched position, to maintain said safety switch means in a closed position with oven cavity temperatures exceeding those oven temperatures at which a door-locked condition is required.

Claim 10

An oven according to claim 7 wherein: said means for changing the condition of said safety switch means relative to said switch-operating means, in accordance with operation of said latching means to a latched condition, is effective to condition said safety switch means and said switch-operating means for operation of said safety switch means to an open position with oven cavity temperatures exceeding a predetermined established upper liMit of the heat-cleaning temperature range.