초록 ▼

A power control switching arrangement for controlling energization of a load in response to an external controller, in which a first semiconductor switch is connected in parallel with the series combination of a first normally open thermally actuated switch and a second normally closed thermally act

A power control switching arrangement for controlling energization of a load in response to an external controller, in which a first semiconductor switch is connected in parallel with the series combination of a first normally open thermally actuated switch and a second normally closed thermally actuated switch, to couple the power signal to the load. A first heater for the first thermal switch is connected in parallel with the load. A second heater for the second thermal switch is connected in series with a second semiconductor switch, across the power supply. The second semiconductor switch, when switched into conduction by the controller, enables energization of the second heater. To energize the load, the controller switches the first semiconductor switch into conduction enabling energization of the load and the first heater. Energization of the first heater closes the first thermally actuated switch, thereby shunting the first semiconductor switch. To de-energize the load, the controller switches the second semiconductor switch into conduction, enabling energization of the second heater. This opens the second thermally actuated switch de-energizing the load and the first heater. De-energization of the first heater enables the first thermally actuated switch to return to its normally open state.

대표청구항 ▼

A power control switching arrangement for selectively coupling a power signal from an external power supply to an electrical load in response to trigger signals from an external controller, said arrangement comprising: a first semiconductor switch means for coupling the power signal from the externa

A power control switching arrangement for selectively coupling a power signal from an external power supply to an electrical load in response to trigger signals from an external controller, said arrangement comprising: a first semiconductor switch means for coupling the power signal from the external power supply to the load, having a gate terminal, and being switched into conduction by a trigger signal at its gate terminal from the external controller; a first thermally actuated switch means operative to switch when heated from a normally open state to a closed state; a second thermally actuated switch means operative to switch when heated from a normally closed state to an open state; said first and second thermally actuated switch means being electrically connected in parallel circuit with said first semiconductor switch means to shunt said first semiconductor switch member when both therally actuated switch means are in said closed states; first heater means arranged for electrical connection in parallel circuit with the load operative when energized to heat said first thermally actuated switch means; second heater means electrically connected in series circuit with a second semiconductor switch means, arranged for electrical connection across the power supply, operative when energized to heat said second thermally actuated switch means, said second semiconductor switch means having a gate terminal and being switched into conduction by a trigger signal from the controller applied to its gate terminal; whereby a trigger signal at the gate of said first semiconductor switch means enables energization of the load and said first heater means, causing said first thermally actuated switch means to switch to its closed state thereby shunting said first semiconductor switch means, and a trigger signal applied to the gate terminal of said second semiconductor switch means enables energization of said second heater means causing said second thermally actuated switch means to switch to its open state thereby de-energizing the load, and de-energizing said first heater means to enable said first thermally actuated switch means to return to its normally open state.