Patent ID: 6509658
Filing Date: 2003-01-21
Classification: H02M,H03K

Abstract:
A device for the automatic shut-off of equipment's stand-by power including a first and second fine for a commercial alternating current;a first relay for switching contacts of the first line; a second relay for switching contacts of the second line; and a power switching controller for detecting whether a light is present and for sequentially switching the contact states of the first relay and second relay depending on the result of the light detection to thereby allow or cut off the commercial alternating current through the first and second lines, which comprises: a sensor section for detecting whether the light is present and for generating and outputting a detection signal when the light is present; a first relay driver for being activated in the case of no reception of the detection signal to switch the contact states of the first relay so that the commercial alternating current is not output through the first line; a delay section for generating and outputting driving pulses after a delay of predetermined time following the activation of the first relay driver, and a second relay driver for being activated upon the reception of driving pulses to switch the contact states of the second relay so that the commercial alternating current is not output through the second line.