Patent ID: 8912725

Claim:
A photoswitch, comprising a DC power supply, comprising a positive electrode and a negative electrode; a luminance controlling circuit, in electrical connection with said DC power supply; a lightening apparatus, controlled by said luminance controlling circuit; wherein said luminance controlling circuit comprises a relay (RL 1 ), comprising a current input end, a current output end and a contact; a trigger circuit module, comprising a current output end, a NPN triode (Q 1 ), a NPN triode (Q 2 ), and a PNP triode (Q 3 ), adapted for switching on or switching off said relay (RL 1 ); a delay discharge circuit module, comprising a positive electrode and a negative electrode, adapted for supplying power for said trigger circuit module and activating said trigger circuit module; a photosensitive element ( 1 ), in series connection with said delay discharge circuit module; and an adjusting circuit module, comprising a resistor (R 4 ), a resistor (R 5 ) and a resistor (R 7 ), adapted for setting a value of luminance for turning on or off a light; said contact of said relay (RL 1 ), in series connection with said lightening apparatus, is adapted for switching on or switching off said lightening apparatus; said current output end of said trigger circuit module is in connection with said relay (RL 1 ); a collector and a base of said triode (Q 1 ) are in connection with said positive electrode and said negative electrode of said delay discharge circuit module respectively, and the collector of said triode (Q 1 ) is further in connection with said positive electrode of said DC power supply, and a emitter of said triode (Q 1 ) is in connection with said negative electrode of said DC power supply through a resistor (R 3 ), and the emitter of said triode (Q 1 ) is further in connection with the emitter of said triode (Q 2 ); a base of said triode (Q 2 ) is in connection with a current output end of a resistor (R 4 ), and said resistor (R 4 ) and a resistor (R 5 ) are in series connection with each other and arranged between said positive electrode and said negative electrode of said DC power supply, and a collector of said triode (Q 2 ) is in connection with said positive electrode of said DC power supply through a series resistor (R 6 ); a base of said triode (Q 3 ) is in connection with a collector of said triode (Q 2 ), and an emitter of said triode (Q 3 ) is in connection with said positive electrode of said DC power supply, and a collector of said triode (Q 3 ) is in connection with said current input end of said relay (RL 1 ); a current output end of said delay discharge circuit module is in connection with said trigger circuit module; one end of said resistor (R 7 ) is in connection with a current output end of said resistor (R 4 ) and the other end is in connection with said current input end of said relay (RL 1 ); a current value of a subcircuit with said resistor (R 7 ) and said relay (RL 1 ) is smaller than a pull-in current value or a release current value of said relay (RL 1 ).