| 摘要 |
<p>A control circuit for a microwave oven is disclosed which functions to automatically control the running time of the microwave generator to enable it to run continuously, during its cooking cycle, or intermittently, during its defrosting cycle. The control circuit includes a timer control switch operatively coupled to a timer motor. The timer control switch functions to control the current flow from the source of electrical power to the microwave generator. The circuit also includes a defrost control switch which functions to cyclically open and close a series current path to the microwave generator. A bypass circuit is also provided across the defrost control switch to short-circuit the defrost switch and provide a bypass current path to the microwave generator. A "cook-defrost" switch is provided to connect the circuit to the bypass circuit for the cooking mode, or to disconnect the bypass circuit to enable the current path to be governed by the defrost control switch for the defrosting mode. In one embodiment, the defrost control switch is coupled to a second timer motor which, in turn, is adapted to be cut into and out of the circuit by the "cook-defrost" switch. In a second embodiment, the defrost control switch is coupled to the first timer motor and is continuously operated thereby.</p> |
