Method for judging discharge state of ink jet recording head, and ink jet recording apparatus utilizing the same

• US 6,305,776 B1
• Filed: 04/30/1993
• Issued: 10/23/2001
• Est. Priority Date: 05/08/1992
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ohshima, Noriyoshi, Takahashi, Seiji, Shimamura, Yoshiyuki
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): SHAH, MANISH S
• Application Number:
  US08/054,193
• Time in Patent Office: 3,098 Days
• Field of Search: 346/104.R, 346/1.1, 347/14, 347/17, 347/23
• US Class Current: 347/17
• CPC Class Codes: B41J 2/0451 for detecting failure, e.g. clogging, malfunctioning actuator
• CPC Class Codes: B41J 2/04563 detecting head temperature; Ink temperature
• CPC Class Codes: B41J 2/0458 controlling heads based on heating elements forming bubbles
• CPC Class Codes: B41J 2/04596 Non-ejecting pulses
• CPC Class Codes: B41J 2/16579 Detection means therefor, e.g. for nozzle clogging
• CPC Class Codes: B41J 2/17553 Outer structure

Abstract

The temperature characteristics of an ink jet recording head are detected, and the result of detection is utilized for detecting the ink discharge state. Also a statistical processing on the temperature characteristics detected on plural recording heads enables exact detection of the ink discharge state, not effected by the individual difference of the recording heads. Also there is detected the abnormality in ink discharge, that may occur prior to the exhaustion of ink in the ink tank.

Claims

1. An ink jet recording apparatus for recording on a recording medium using a recording head mounted thereto for discharging an ink from a plurality of discharge openings onto the recording medium, comprising:

an electrothermal converter provided on said recording head;

temperature detection means, thermally coupled to said recording head, for detecting a temperature of said recording head; and

temperature characteristic detection means for applying a predetermined amount of energy to said electrothermal converter, and detecting a temperature change of said recording head resulting from an application of the predetermined energy, thereby determining a temperature characteristic of said recording head mounted to the apparatus, based on a result of such detecting, said temperature characteristic being a specific characteristic of said recording head.

2. An ink jet recording apparatus according to claim 1, further comprising:

judgment means for judging an ink discharge state of said recording head, based on the result of such detecting of the temperature characteristic of the recording head by said temperature characteristic detection means, and providing a judgment result.

3. An ink jet recording apparatus according to claim 2, further comprising:

informing means for providing information, based on the judgment result of the ink discharge state by said judgment means.

4. An ink jet recording apparatus according to claim 2, wherein the temperature detection means for said recording head is provided in a plurality of units, and determining of the temperature characteristic of the recording head and judgment of the ink discharge state are conducted according to a result of temperature detection in a predetermined number of the temperature detection means among said plural units.

5. An ink jet recording apparatus according to claim 2, further comprising:

input means which enables a user to enter an instruction for execution of detection of said ink discharge state, wherein said judgment means judges the ink discharge state in response to the instruction entered by the user through said input means.

6. An ink jet recording apparatus according to claim 1, wherein said electrothermal converter is a heater.

7. An ink jet recording apparatus according to claim 6, wherein the predetermined amount of energy applied to said electrothermal converter is sufficient to induce ink discharge.

8. An ink jet recording apparatus according to claim 6, wherein the predetermined amount of energy applied to said electrothermal converter is insufficient to induce ink discharge.

9. An ink jet recording apparatus according to claim 6, wherein the predetermined amount of energy applied to said electrothermal converter includes an amount inducing ink discharge and another amount not inducing ink discharge.

10. An ink jet recording apparatus according to claim 1, wherein said electrothermal converter is a heater having a purpose other than for ink discharge.

11. An ink jet recording apparatus according to claim 1, wherein said temperature characteristic detection means detects the temperature characteristic of said recording head based on a temperature increase of said recording head detected by said temperature detection means, when said predetermined energy is applied to said electrothermal converter.

12. An ink jet recording apparatus according to claim 1, wherein said temperature characteristic detection means detects the temperature characteristic of said recording head, based on a temperature decrease of said recording head detected by said temperature detection means, after the applying of the predetermined amount of energy to said electrothermal converter.

13. An ink jet recording apparatus according to claim 1, wherein the applying of said predetermined amount of energy to said electrothermal converter is conducted by supplying plural pulses in cycles at a predetermined interval.

14. An ink jet recording apparatus according to claim 13, wherein detecting the temperature change in said recording head by said temperature detection means is conducted in synchronization with the cycles of said pulses.

15. An ink jet recording apparatus according to claim 1, further comprising:

ambient temperature detection means for detecting an ambient temperature of said recording head, wherein said temperature characteristic detection means corrects the result of detection of the temperature change in said recording head, according to the ambient temperature detected by said ambient temperature detection means.

16. An ink jet recording apparatus according to claim 1, further comprising:

ambient temperature detection means for detecting an ambient temperature of said recording head, wherein said temperature characteristic detection means varies the amount of energy applied to said electrothermal converter for the purpose of determining the temperature characteristic of said recording head, based on the ambient temperature detected by said ambient temperature detection means.

17. An ink jet recording apparatus according to claim 1, further comprising:

an ink receiving member for receiving the ink discharged from the discharge opening of said recording head; and

means for controlling the relative position of said recording head and said ink receiving member in such a manner that said recording head opposes said ink receiving member when an energy sufficient to induce ink discharge is applied to said electrothermal converter, to detect the temperature characteristic of said recording head.

18. An ink jet recording apparatus according to claim 1, further comprising:

an ink receiving member for receiving the ink discharged from the discharge opening of said recording head;

means for removing the ink from said ink receiving member; and

means for activating said ink removing means, at the application of energy in an amount sufficient to induce ink discharge to said electrothermal converter to detect the temperature characteristic of said recording head, at least before the energy application.

19. An ink jet recording apparatus according to claim 1, wherein the temperature characteristic of said recording head includes the temperature change therein when energy in an amount insufficient to induce the ink discharge is applied to said electrothermal converter.

20. An ink jet recording apparatus according to claim 1, wherein the temperature characteristic of said recording head includes the temperature change therein when energy in an amount sufficient to induce the ink discharge is applied to said electrothermal converter, in a state in which said recording head is filled with the ink.

21. An ink jet recording apparatus according to claim 1, wherein the temperature characteristic of said recording head includes a temperature change therein when the energy in an amount sufficient to induce ink discharge is applied to said electrothermal converter, in a state in which said recording head is not filled with the ink.

22. An ink jet recording apparatus according to claim 1, wherein said recording head induces a state change including bubble generation in the ink, using thermal energy, and effects ink discharge based on said state change.

23. An ink jet recording apparatus according to claim 1, wherein said temperature characteristic is specified with respect to said recording head.

25. An ink jet recording apparatus according to claim 1, wherein the temperature characteristic of said recording head is a characteristic resulting from a difference between at least one of a heat generation amount and a heat dissipation amount of said recording head and that of at least one other associated recording head.

24. A method of recording upon a recording medium, comprising the steps of:

providing an ink jet recording apparatus for recording on the recording medium using a mounted recording head for discharging ink from a plurality of discharge openings onto the recording medium, the recording apparatus including an electrothermal converter provided on the recording head;

detecting a temperature of the recording head; and

applying a predetermined amount of energy to said electrothermal converter, and detecting a temperature change of said recording head resulting from an application of the predetermined energy, thereby determining a temperature characteristic of said recording head mounted to the apparatus, based on a result of said detecting, the temperature characteristic being a specific characteristic of the recording head.

26. A method according to claim 24, wherein the temperature characteristic of said recording head is a characteristic resulting from a difference between at least one of a heat generation amount and a heat dissipation amount of said recording head and that of at least one other associated recording head.