IMAGE FORMING APPARATUS

• US 20120025630A1
• Filed: 07/25/2011
• Published: 02/02/2012
• Est. Priority Date: 07/28/2010
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Tec Corporation (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Tec Corporation (Toshiba Corporation)
• Inventors: TSUDA, Kenichi
• Granted Patent: US 8,901,780 B2
• Time in Patent Office: Days
• US Class Current: 307/125
• CPC Class Codes: G03G 15/5004 Power supply control, e.g. power-saving mode, automatic power turn-off
• CPC Class Codes: G03G 15/80 Details relating to power supplies, circuits boards, electrical connections
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H02J 9/005 using a power saving mode for copiers G03G15/5004
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y04S 20/20 End-user application control systems

Abstract

There is provided an image forming apparatus including: a load device which performs a copy function, a scan function, a print function and the like; and a power saving mode such as a standby mode and a sleep mode. When the image forming apparatus is in the power saving mode, electric charge charged in an electric storage device such as an electrolytic capacitor which is a low voltage power source is used to execute the power saving mode. When an electric potential of the electric storage device is lower than a predetermined threshold, the electric storage device is charged by a commercial power source.

Claims

1. An image forming apparatus which converts an AC voltage from a commercial power source into a DC voltage through a rectifying circuit and an electric storage device and supplies the DC voltage to a load through a transformer,

wherein a relay is installed between the commercial power source and the rectifying circuit;

the electric storage device is capable of charging and discharging, and an electric storage device residual potential monitoring circuit is connected to an output terminal of the electric storage device;

the load comprises a load device, a power saving mode control section, and a power saving mode shift detecting section which detects that the load shifts to a power saving mode and outputs a power saving mode shift signal; and

if the power saving mode shift signal is input to the electric storage device residual potential monitoring circuit, a relay opening and closing signal for instructing opening and closing of the relay is output from the electric storage device residual potential monitoring circuit, the relay is opened to cut off the supply of the commercial power source, and electric charge charged in the electric storage device is supplied to the power saving mode control section.

2. The apparatus according to claim 1,

wherein the electric storage device is an electrolytic capacitor.

3. The apparatus according to claim 2,

wherein the electrolytic capacitor is an aluminum electrolytic capacitor.

4. The apparatus according to claim 1,

wherein the electric storage device is an electric double layer capacitor.

5. The apparatus according to claim 2,

wherein a threshold is set to the electric storage device residual potential monitoring circuit;

a residual potential of the electric storage device is compared with the threshold; and

if the residual potential of the electric storage device is lower than the threshold, the relay opening and closing signal is output and the relay is closed to charge the electric storage device by the commercial power source,

wherein the residual potential of the electric storage device is equal to or higher than the threshold, the relay opening and closing signal is output and the relay is opened to supply the electric charge charged in the electric storage device to the power saving mode control section.

6. The apparatus according to claim 2,

wherein the electric storage device residual potential monitoring circuit outputs the relay opening and closing signal to repeat charging and discharging of the electric storage device.

7. The apparatus according to claim 4,

wherein a threshold is set to the electric storage device residual potential monitoring circuit;

a residual potential of the electric storage device is compared with the threshold; and

if the residual potential of the electric storage device is lower than the threshold, the relay opening and closing signal is output and the relay is closed to charge the electric storage device by the commercial power source,

wherein the residual potential of the electric storage device is equal to or higher than the threshold, the relay opening and closing signal is output and the relay is opened to supply the electric charge charged in the electric storage device to the power saving mode control section.

18. The apparatus according to claim 1,

wherein the electric storage device residual potential monitoring circuit outputs the relay opening and closing signal to repeat charging and discharging of the electric storage device.

19. The apparatus according to claim 18,

wherein the repetition of the charging and discharging of the electric storage device is continued while the power saving mode shift signal is being input to the electric storage device residual potential monitoring circuit.

20. The apparatus according to claim 1,

wherein if the power saving mode shift signal is not input to the electric storage device residual potential monitoring circuit, the relay is closed by the relay opening and closing signal.

8. An image forming apparatus which converts an AC voltage from a commercial power source into a DC voltage through a rectifying circuit and an electric storage device and supplies the DC voltage to a load through a transformer,

wherein a relay is installed between the commercial power source and the rectifying circuit;

the electric storage device is capable of charging and discharging, and an electric storage device residual potential monitoring circuit is connected to an output terminal of the electric storage device;

the load comprises a load device, a power saving mode control section, and a power saving mode shift detecting section which detects that the load shifts to a power saving mode and outputs a power saving mode shift signal;

the power saving mode control section comprises a standby mode control section and a sleep mode control section; and

if the power saving mode shift signal is input to the electric storage device residual potential monitoring circuit, a relay opening and closing signal for instructing opening and closing of the relay is output from the electric storage device residual potential monitoring circuit, the relay is opened to cut off the supply of the commercial power source, and electric charge charged in the electric storage device is supplied to the power saving mode control section.

9. The apparatus according to claim 8,

wherein a threshold is set to the electric storage device residual potential monitoring circuit;

a residual potential of the electric storage device is compared with the threshold; and

if the residual potential of the electric storage device is lower than the threshold, the relay opening and closing signal is output and the relay is closed to charge the electric storage device by the commercial power source,

wherein the residual potential of the electric storage device is equal to or higher than the threshold, the relay opening and closing signal is output and the relay is opened to supply the electric charge charged in the electric storage device to the power saving mode control section.

10. The apparatus according to claim 8,

wherein the electric storage device residual potential monitoring circuit outputs the relay opening and closing signal to repeat charging and discharging of the electric storage device.

11. The apparatus according to claim 10,

wherein the repetition of the charging and discharging of the electric storage device is continued while the power saving mode shift signal is being input to the electric storage device residual potential monitoring circuit.

12. The apparatus according to claim 8,

wherein if the power saving mode shift signal is not input to the electric storage device residual potential monitoring circuit, the relay is closed by the relay opening and closing signal.

13. An image forming apparatus which converts an AC voltage from a commercial power source into a DC voltage through a rectifying circuit and an electric storage device and supplies the DC voltage to a load through a transformer,

wherein a relay is installed between the commercial power source and the rectifying circuit;

the electric storage device is capable of charging and discharging, and an electric storage device residual potential monitoring circuit is connected to an output terminal of the electric storage device;

the load comprises a load device, a power saving mode control section, and a power saving mode shift detecting section which detects that the load shifts to a power saving mode and outputs a power saving mode shift signal; and

if the power saving mode shift signal is input to the electric storage device residual potential monitoring circuit, a relay opening and closing signal for instructing opening and closing of the relay is output from the electric storage device residual potential monitoring circuit, the relay is opened to cut off the supply of the commercial power source, and electric charge charged in the electric storage device is supplied to the power saving mode control section,

wherein a threshold is set to the electric storage device residual potential monitoring circuit;

a residual potential of the electric storage device is compared with the threshold; and

if the residual potential of the electric storage device is lower than the threshold, the relay opening and closing signal is output and the relay is closed to charge the electric storage device by the commercial power source.

14. The apparatus according to claim 13,

wherein if the residual potential of the electric storage device is equal to or higher than the threshold, the relay opening and closing signal is output and the relay is opened to supply the electric charge charged in the electric storage device to the power saving mode control section.

15. The apparatus according to claim 13,

wherein the electric storage device residual potential monitoring circuit outputs the relay opening and closing signal to repeat charging and discharging of the electric storage device.

16. The apparatus according to claim 15,

wherein the repetition of the charging and discharging of the electric storage device is continued while the power saving mode shift signal is being input to the electric storage device residual potential monitoring circuit.

17. The apparatus according to claim 13,

wherein the power saving mode control section comprises a standby mode control section and a sleep mode control section.