Oven temperature limiter

Claim 2

An oven having an oven temperature control assembly comprising: a circuit extending between electrical input terminals to oven-heating elements for energizing the same; means in said energizing circuit for sensing oven temperature to selectively energize said oven-heating elements for maintaining a preselected temperature within the oven; said sensing means including a curved Bourdon tube having a pressurized interior filled with a thermally expansive material to cause straightening of the tube with increasing oven temperatures; a contact pair operably controlled by movement of said Bourdon tube to cause said contacts to close only when said thermally expansive material leaks from said Bourdon tube, thus permitting it to assume a fully relaxed operative position which is more curved than the position assumed at room temperature and pressure; circuit breaking means in said energizing circuit adapted to terminate the energization of said heating elements when the circuit breaker is opened; the terminals of said contact pair being connected respectively to one input terminal of said energization circuit and to one side of said circuit breaking means to produce a shortcircuit extending through said contact pair and said circuit breaking means when said contact pair is closed, whereby an excessive current opens said circuit breaking means to terminate oven energization.

Claim 3

An oven having an oven temperature control assembly comprising: a circuit extending between electrical input terminals to oven-heating elements for energizing the same; means in said energization circuit sensing oven temperature to selectively energize said oven-heating elements for maintaining a preselected temperature within the oven; said sensing means including a curved Bourdon tube having a pressurized interior filled with a thermally expansive material to cause straightening of the tube with increasing oven temperatures; a switch arm having a contact operably controlled by said Bourdon tube and normally maintained a spaced distance from an associated contact under all operaTive conditions by the pressurized material within the interior of said Bourdon tube; said contact arm being moved into engagement with said associated contact when the tube interior is depressurized caused by discharge of material from said Bourdon tube interior, thus permitting the tube to assume a fully relaxed operative position which is more curved than the position assumed at room temperatures and pressures; a fuse in said energizing circuit adapted to terminate the energization of said heating elements when the fuse is opened; said contacts being connected respectively to one input terminal of said energization circuit and to one side of said fuse to produce a short-circuit extending through said contacts and said fuse when said contacts are engaged whereby an excessive current flows through said fuse to open it and terminate oven energization.

Claim 4

An oven having an oven temperature control assembly comprising: a circuit extending between electrical input terminals to oven-heating elements for energizing the same; means in said energization circuit sensing oven temperature to selectively energize said oven-heating elements for maintaining a preselected temperature within the oven; said sensing means including a curved Bourdon tube having a pressurized interior filled with a thermally expansive material to cause straightening of the tube with increasing oven temperatures; a switch arm having a contact operably controlled by said Bourdon tube and normally maintained a spaced distance from an associated contact under all operaTive conditions by the pressurized material within the interior of said Bourdon tube; said contact arm being moved into engagement with said associated contact when the tube interior is depressurized caused by discharge of material from said Bourdon tube interior, thus permitting the tube to assume a fully relaxed operative position which is more curved than the position assumed at room temperatures and pressures; a fuse in said energizing circuit adapted to terminate the energization of said heating elements when the fuse is opened; said contacts being connected respectively to one input terminal of said energization circuit and to one side of said fuse to produce a short-circuit extending through said contacts and said fuse when said contacts are engaged whereby an excessive current flows through said fuse to open it and terminate oven energization.