| 摘要 |
<p>889,449. Control of heating resistors. GENERAL ELECTRIC CO. July 10, 1958 [July 12, 1957], No. 22167/58. Class 38 (4). [Also in Group XXXVII] In a control circuit for an electric blanket, a heater wire 7 is separated from a control wire 8 by a thermo-sensitive layer 9. Operation of a start-push 10 closes contacts 11 to energize an operating-coil 4 of a relay 2 and simultaneously open contacts 12 to isolate the heater wire from contacts 14 of the relay 2. Closing of the contacts 14 energizes a holding-coil 3, lights an indicating neon lamp 15, and on release of the start-push feeds the heater wire through an ambient temperature-responsive device 17. Over-heating of the thermo-sensitive layer causes the relay 2 to be released due to the operating-coil acting as a number of shorted turns or setting up a flux opposing that due to the holding-coil. A stop-push 18 short-circuits the operating coil. In another embodiment, Fig. 2 (not shown), only one end of the control wire is connected to the operating-coil, the startpush being replaced by a push manually closing the relay 2, and the stop-push is connected to short - circuit the holding - coil. Specification 696,369 is referred to.</p> |
