| 摘要 |
A temperature cutout for an electrical heater of the cartridge type having a resistance element wound on an insulating core disposed within a metal sheath and surrounded by insulating material, a first conductor in electrical contact with said resistance element and a second conductor freely disposed within said core, having one end portion normally in electrical contact with said first conductor, said second conductor having a relatively lower coefficient of expansion than said sheath and being sized electrically for self-heating and axial extension and retraction responsive to the current flow, whereby upon attaining a preselected first temperature during heating, contact between said conductors will be broken and said second conductor will cool and contract for rapidly separating said conductors; and upon reaching a relatively lower second temperature during cooling, contact between conductors will be reestablished and said second conductor will heat and extend for rapidly engaging said conductor so that cycling is reduced and arcing is substantially eliminated.
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