Remaining-amount-of-battery detecting device

• US 6,232,747 B1
• Filed: 07/13/2000
• Issued: 05/15/2001
• Est. Priority Date: 12/11/1989
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Saeki, Takayuki, Takimoto, Hiroyuki, Tobe, Kazumitsu, Harigaya, Isao, Takahashi, Koji
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US09/615,207
• Time in Patent Office: 306 Days
• Field of Search: 320/124, 320/125, 320/132, 320/139, 320/149, 320/160, 320/161, 320/162, 320/164, 324/426, 324/427
• US Class Current: 324/427
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/374 with means for correcting the measurement for temperature or ageing
• CPC Class Codes: G01R 31/386 using test-loads

Abstract

A remaining-amount-of-battery detecting device according to the present invention detects the remaining amount of battery power. The device is arranged to measure the open-circuit voltage of a battery and detect the remaining amount of battery power on the basis of the measured open-circuit voltage of the battery, so that it is possible to accurately detect the remaining amount of battery power.

Claims

1. A device for detecting a state of charge of a battery, comprising:

(A) measuring means for measuring an output of a battery connected to a load which has a varying resistance value before and after change of the resistance value of the load; and

(B) detecting means for performing a predetermined computation on the basis of a measuring result of the load before and after the change of the resistance value to detect the state of charge of the battery on the basis of the computation result.

2. A device according to claim 1, wherein said detecting means computes an open circuit voltage of the battery on the basis of the measuring result of the measuring means, and detects the state of charge of the battery by using a memory which memorized a relation between the open-circuit voltage of the battery and the state of charge of the battery.

3. A device according to claim 1, wherein the state of charge of the battery is supplied to a display portion which displays a remaining service time of the battery.

4. A device according to claim 1, wherein the resistance value of the load varies in accordance with operation condition of the load.

5. A device according to claim 4, wherein the operation condition includes at least a recording mode.

6. A device according to claim 1, wherein the load is composed of a video camera.

7. A device for detecting a state of charge of a battery, comprising:

(A) measuring means for measuring an output of the battery connected to a load which shows a varying resistance value; and

(B) detecting means for determining a kind of the battery and detecting the state of charge of the battery on the basis of a measuring result of the measuring means.

8. A device according to claim 7, wherein said detecting means computes an open-circuit voltage of the battery on the basis of the measuring result of the measuring means, and detects the state of charge of the battery by using a memory which memorized a relation between the open-circuit voltage of the battery and the state of charge of the battery.

9. A device according to claim 7, wherein the state of charge of the battery is supplied to a display portion which displays a remaining service time of the battery.

10. A device according to claim 7, wherein the resistance value of the load varies in accordance with operation condition of the load.

11. A device according to claim 10, wherein the operation condition includes at least a recording mode.

12. A device according to claim 7, wherein the load is composed of a video camera.

13. A method of detecting a state of charge of a battery, comprising:

(A) measuring an output of a battery connected to a load which has a varying resistance value before and after change of the resistance value of the load; and

(B) performing a predetermined computation on the basis of a measuring result of the load before and after the change of resistance value to detect the state of charge of the battery on the basis of the computation result.

14. A method according to claim 13, wherein the state of charge of the battery is detected by using a memory which memorized a relation between an open-circuit voltage of the battery and the state of charge of the battery, and the open-circuit voltage of the battery is computed on the basis of the measuring result of the measuring means.

15. A method according to claim 13, wherein the state of charge of the battery is supplied to a display portion which displays a remaining service time of the battery.

16. A method according to claim 13, wherein the resistance value of the load varies in accordance with operation condition of the load.

17. A method according to claim 16, wherein the operation condition includes at least a recording mode.

18. A method according to claim 13, wherein the load is composed of a video camera.

19. A method of detecting a state of charge of a battery, comprising:

(A) measuring an output of the battery connected to a load which shows a varying resistance value; and

(B) determining a kind of the battery and detecting the state of charge of the battery on the basis of a measuring result of the measuring means.

20. A method according to claim 19, wherein the stale of charge of the battery is detected by using a memory which memorized a relation between an open-circuit voltage of the battery and the state of charge of the battery, and the open-circuit voltage of the battery is computed on the basis of the measuring result of the measuring means.

21. A method according to claim 19, wherein the state of charge of the battery is supplied to a display portion which displays a remaining service time of the battery.

22. A method according to claim 19, wherein the resistance value of the load varies in accordance with operation condition of the load.

23. A method according to claim 22, wherein the operation condition includes at least a recording mode.

24. A method according to claim 19, wherein the load is composed of a video camera.

25. A device for detecting a state of charge of a battery, comprising:

(A) measuring means for measuring a first output of the battery when a load connected to the battery is in a first operation condition and a second output of the battery when the load connected to the battery is in a second operation, condition, the load has a varying resistance value;

(B) detecting means for performing predetermined computation on the basis of both the first output of the battery and the second output of the battery to detect the state of charge of the battery.

26. A device according to claim 25, wherein said detecting means computes an open-circuit voltage of the battery on the basis of both the first output and the second output, and detects the state of charge of the battery by using a memory which memorized a relation between the open circuit voltage of the battery and the state of charge of the battery.

27. A device according to claim 25, wherein the state of charge of the battery is supplied to a display portion which displays a remaining service time of the battery.

28. A device according to claim 25, wherein one of the first operation condition and the second operation condition is a recording mode.

29. A device according to claim 25, wherein the load is composed of a video camera.

30. A method of detecting a state of charge of a battery, comprising:

(A) measuring a first output of the battery when a load connected to the battery is in a first operation condition and a second output of the battery when the load connected to the battery is in a second operation condition, the load has a varying resistance value; and

(B) performing predetermined computation on the basis of both the first output of the battery and the second output of the battery to detect the state of charge of the battery.

31. A method according to claim 30, wherein the state of charge of the battery is detected by using a memory which memorized a relation between an open-circuit voltage of the battery and the state of charge of the battery, and the open-circuit voltage of the battery is computed on the basis of both the first output and second output.

32. A method according to claim 30, wherein the state of charge of the battery is supplied to a display portion which displays a remaining service time of the battery.

33. A method according to claim 30, wherein one of the first operation condition and the second operation condition is a recording mode.

34. A method according to claim 30, wherein the load is composed of a video camera.