Power supply apparatus and image forming apparatus

1. A power supply apparatus comprising:

a rectifying and smoothing unit configured to rectify and smooth an AC voltage of an AC power supply;

a transformer having a primary winding, a first secondary winding and a second secondary winding connected to the first secondary winding through a signal line, the transformer configured to convert a voltage output from the rectifying and smoothing unit to output a first voltage to be supplied to a load;

a detecting unit connected to the signal line between the first secondary winding and the second secondary winding, the detecting unit configured to detect a second voltage according to a voltage output from the rectifying and smoothing unit; and

a first control unit configured to control a state of the load based on a result detected by the detecting unit.

2. The power supply apparatus according to claim 1 , comprising a memory unit configured to store information in which the AC voltage or a voltage output from the rectifying and smoothing unit and a state of the load are associated with the AC voltage or the voltage,

wherein the first control unit controls a state of the load based on the result detected by the detecting unit and the information stored in the memory unit.

3. The power supply apparatus according to claim 1 , comprising:

a switching element connected to the primary winding;

a second control unit configured to control a switching operation of the switching element; and

a feedback unit configured to feed back a voltage according to the first voltage to the second control unit.

4. The power supply apparatus according to claim 3 , wherein based on the result detected by the detecting unit, the first control unit performs control to shift a state of the load to any one state among a first state in which the power supply apparatus is stopped, a second state in which the power supply apparatus is operating and the load is stopped, a third state in which power consumed by the load is greater than power in the second state, and a fourth state in which power consumed by the load is greater than power in the third state.

5. The power supply apparatus according to claim 4 , wherein the first control unit:

performs control to shift a state of the load to the first state in a case where a voltage detected by the detecting unit is less than a first threshold voltage;

performs control to shift a state of the load to the second state in a case where a voltage detected by the detecting unit is greater than the first threshold voltage and less than a second threshold voltage;

performs control to shift a state of the load to the third state in a case where a voltage detected by the detecting unit is greater than the second threshold voltage and less than a third threshold voltage; and

performs control to shift a state of the load to the fourth state in a case where a voltage detected by the detecting unit is greater than the third threshold voltage.

6. An image forming apparatus configured to form an image on a recording medium, the image forming apparatus having a power supply apparatus configured to supply power to the image forming apparatus,

wherein the power supply apparatus comprises:

a rectifying and smoothing unit configured to rectify and smooth an AC voltage of an AC power supply;

a transformer having a primary winding, a first secondary winding and a second secondary winding connected to the first secondary winding through a signal line, the transformer configured to convert a voltage output from the rectifying and smoothing unit to output a first voltage to be supplied to a load;

a detecting unit connected to the signal line between the first secondary winding and the second secondary winding, the detecting unit configured to detect a second voltage according to a voltage output from the rectifying and smoothing unit; and

a first control unit configured to control a state of the load based on a result detected by the detecting unit.

7. The image forming apparatus according to claim 6 , comprising a memory unit configured to store information in which the AC voltage or a voltage output from the rectifying and smoothing unit and a state of the load are associated with the AC voltage or the voltage,

wherein the first control unit controls a state of the load based on the result detected by the detecting unit and the information stored in the memory unit.

8. The image forming apparatus according to claim 6 , comprising:

a switching element connected to the primary winding;

a second control unit configured to control a switching operation of the switching element; and

a feedback unit configured to feed back a voltage according to the first voltage to the second control unit.

9. The image forming apparatus according to claim 8 , wherein based on the result detected by the detecting unit, the first control unit performs control to shift a state of the load to any one state among a first state in which the power supply apparatus is stopped, a second state in which the power supply apparatus is operating and the load is stopped, a third state in which power consumed by the load is greater than power in the second state, and a fourth state in which power consumed by the load is greater than power in the third state.

10. The image forming apparatus according to claim 9 , wherein the first control unit:

performs control to shift a state of the load to the first state in a case where a voltage detected by the detecting unit is less than a first threshold voltage;

performs control to shift a state of the load to the second state in a case where a voltage detected by the detecting unit is greater than the first threshold voltage and less than a second threshold voltage;

performs control to shift a state of the load to the third state in a case where a voltage detected by the detecting unit is greater than the second threshold voltage and less than a third threshold voltage; and

performs control to shift a state of the load to the fourth state in a case where a voltage detected by the detecting unit is greater than the third threshold voltage.

11. The image forming apparatus according to claim 10 ,

wherein the third state is a state in which the image forming apparatus stands by for input of print data, and

wherein the fourth state is a state in which it is possible to perform image forming operations.

12. The image forming apparatus according to claim 9 ,

wherein the third state is a state in which the image forming apparatus stands by for input of print data, and

wherein the fourth state is a state in which image forming operations are enabled.

13. A power supply apparatus comprising:

a rectifying and smoothing unit configured to rectify and smooth an AC voltage of an AC power supply;

a transformer having a primary winding, a first secondary winding and a second secondary winding, the first secondary winding configured to convert a voltage output from the rectifying and smoothing unit to output a first voltage to be supplied to a load and the second secondary winding configured to convert the output from the rectifying and smoothing unit to output a second voltage;

a detecting unit connected to the second secondary winding, the detecting unit configured to detect the second voltage; and

a first control unit configured to control a state of the load based on a result detected by the detecting unit.

14. An image forming apparatus configured to form an image on a recording medium, the image forming apparatus having a power supply apparatus configured to supply power to the image forming apparatus,

wherein the power supply apparatus comprises:

a rectifying and smoothing unit configured to rectify and smooth an AC voltage of an AC power supply;

a transformer having a primary winding, a first secondary winding and a second secondary winding, the first secondary winding configured to convert a voltage output from the rectifying and smoothing unit to output a first voltage to be supplied to a load and the second secondary winding configured to convert the output from the rectifying and smoothing unit to output a second voltage;

a detecting unit connected to the second secondary winding, the detecting unit configured to detect the second voltage; and

a first control unit configured to control a state of the load based on a result detected by the detecting unit.