Heater control device and image forming apparatus

• US 9,471,014 B2
• Filed: 09/18/2015
• Issued: 10/18/2016
• Est. Priority Date: 01/23/2015
• Status: Active Grant

• Current Assignee: Oki Data Corporation (OKI Electric Industry Company Limited)
• Original Assignee: Oki Data Corporation (OKI Electric Industry Company Limited)
• Inventors: Suzuki, Shuichi
• Primary Examiner(s): Chen, Sophia S
• Application Number:
  US14/858,482
• Publication Number:
  US 20160216663A1
• Time in Patent Office: 396 Days
• Field of Search: 399/88, 399/37, 399/69, 219/216
• US Class Current: 1/1
• CPC Class Codes: G03G 15/2039 with means for controlling the fixing temperature
• CPC Class Codes: G03G 15/80 Details relating to power supplies, circuits boards, electrical connections
• CPC Class Codes: G03G 2215/00666 Heating or drying device

Abstract

A heater control device includes a first voltage conversion part that generates a first voltage based on an external input voltage, a second voltage conversion part that generates a second voltage for supplying power to heater(s) based on the first voltage, a third voltage conversion part that generates a third voltage used at least in driving the heater(s) based on the first voltage, a capacitative element electrically connected to a path that connects the first voltage conversion part to the second voltage conversion part and connects the first voltage conversion part to the third voltage conversion part. The capacitative element is located in a section of the path used for connecting both to the second and to third voltage conversion part, and a control part that performs an operation stop control to stop the operation of at least one heater(s) if the external input voltage has dropped below a first threshold voltage.

Claims

1. A heater control device, comprising:

a first voltage conversion part that generates a first voltage based on an external input voltage that is input from an outside,

a second voltage conversion part that generates a second voltage for supplying power to one or multiple heaters, which are provided inside the device, based on the first voltage,

a third voltage conversion part that generates a third voltage used at least in driving the one or multiple heaters based on the first voltage,

a capacitative element that is electrically connected to a path that

connects the first voltage conversion part to the second voltage conversion part and

connects the first voltage conversion part to the third voltage conversion part,

further the capacitative element being located in a section of the path that is used for connecting both to the second and to third voltage conversion part, and

a control part that performs an operation stop control to stop the operation of at least one of the one or multiple heaters if the external input voltage has dropped below a first threshold voltage.

2. The heater control device according to claim 1, wherein

at least a first switch is provided on a path that connects the second voltage conversion part and one of the heaters,

a second switch is provided on an output path of the third voltage from which the third voltage conversion part outputs, and

the control part performs the operation stop control by setting at least one of the first and second switches to an OFF state.

3. The heater control device according to claim 2, wherein

if both the first and second switches are in an ON state, the control part performs the operation stop control by setting the first and second switches to the OFF state in a specified order.

4. The heater control device according to claim 3, wherein

the specified order means that the control part sets the first switch to the OFF state earlier than the second switch.

5. The heater control device according to claim 2, wherein

the control part sets at least one of the first and second switches to the OFF state after a first period passed since the external input voltage became below the first threshold voltage.

6. The heater control device according to claim 2, wherein

if the external input voltage has recovered to become higher than the first threshold voltage, the control part releases the operation stop control by setting the first and second switches to an ON state.

7. The heater control device according to claim 6, wherein

if both the first and second switches are in the OFF state, the control part releases the operation stop control by setting the first switch to the ON state earlier than the second switch.

8. The heater control device according to claim 6, wherein

the control part sets the first and second switches to the ON state after a second period passed since the external input voltage has recovered to become larger than the first threshold voltage.

9. The heater control device according to claim 1, wherein

the heaters are grouped by multiple types of heaters each of the types having different consumed power from one another, and

the control part stops one type of the heaters as the operation stop control.

10. The heater control device according to claim 9, wherein

the control part preferentially stops the operation of one type of the heaters having larger consumed power compared with the other type of the heaters.

11. The heater control device according to claim 9, wherein

if the external input voltage has recovered to become larger than the first threshold voltage, the control part restores the operation of at least one type of the heaters by releasing the operation stop control.

12. The heater control device according to claim 11, wherein

the control part preferentially restores the operation of the heaters having larger consumed power compared with the other type of the heaters.

13. The heater control device according to claim 1, wherein

if the external input voltage has dropped below a second threshold voltage that is lower than the first threshold voltage, the control part stops the operation of the second voltage conversion part.

14. The heater control device according to claim 13, wherein

a third switch is provided on the path between the first voltage conversion part and the second voltage conversion part, and

the control part stops the operation of the second voltage conversion part by setting the third switch to an OFF state.

15. The heater control device according to claim 14, wherein

immediately after the external input voltage has become below the second threshold voltage, the control part sets the third switch to the OFF state.

16. The heater control device according to claim 14, wherein

if the external input voltage has recovered to become larger than the second threshold voltage,

the control part restores the operation of the second voltage conversion part by setting the third switch to an ON state.

17. The heater control device according to claim 16, wherein

immediately after the external input voltage has recovered to become larger than the second threshold voltage, the control part restores the operation of the second voltage conversion part by setting the third switch to the ON state.

18. The heater control device according to claim 1, wherein

the one or multiple heaters is a fuser heater or a dew condensation prevention heater.

19. The heater control device according to claim 1, wherein

the external input voltage and the second voltage are alternate current voltages, and

the first and third voltages are direct current voltages.

20. An image forming apparatus, comprising:

one or multiple image forming parts,

a first voltage conversion part that generates a first voltage based on an external input voltage that is input from an outside,

a second voltage conversion part that generates a second voltage for supplying power to one or multiple heaters, which are provided inside the apparatus, based on the first voltage,

a third voltage conversion part that generates a third voltage used at least in driving the one or multiple heaters based on the first voltage,

a capacitative element that is electrically connected to a path that

connects the first voltage conversion part to the second voltage conversion part and

connects the first voltage conversion part to the third voltage conversion part,

further the capacitative element being located in a section of the path that is used for connecting both to the second and to third voltage conversion part, and

a control part that performs an operation stop control to stop the operation of at least one of the one or multiple heaters if the external input voltage has dropped below a first threshold voltage.