Power supply control for an image forming apparatus

摘要

A power supply control circuit includes: a power supply unit that outputs the DC voltage for the load operation; a first switch of which opening/closing is controlled by applying the DC voltage from the power supply unit; a second switch which is manually operated to switch over the power supply; and a control unit. The second switch achieves a first state when not manually operated, and achieves a second state when manually operated. The control unit closes the first switch, if the second switch is changed to the second state and thereafter changed to the first state, when the second switch is in the first state and the DC voltage output from the power supply unit is not less than a predetermined value.

主权项

1. An image forming apparatus, comprising:
an image forming unit configured to form an image on a recording medium; a power supply unit to which AC power is input and which outputs a DC voltage for operating the image forming unit; a relay switch of which opening/closing is controlled by the DC voltage output from the power supply unit being applied to a coil of the relay switch; a power switch which is manually operated to switch ON/OFF of the power supply for the image forming apparatus, and achieves a first state when not manually operated and achieves a second state when manually operated, the power switch being connected to the relay switch in series, and the relay switch being put into an open state when the power switch is in the second state and the relay switch being put into a closed state when the power switch is in the first state; a voltage suppressing unit configured to reduce the DC voltage to less than a predetermined value when the relay switch is in a closed state and the power switch is in the first state; and a control unit configured to close the relay switch so as to reduce the DC voltage to less than the predetermined value in order to put the image forming apparatus into a power-off state, if the power switch is changed to the second state and thereafter is changed to the first state, when the power switch is in the first state and the DC voltage is not reduced to less than the predetermined value.