Battery charger, method of and software program for operating a battery charger, and method of and combination for charging a battery

• US 6,456,035 B1
• Filed: 09/29/2000
• Issued: 09/24/2002
• Est. Priority Date: 08/14/1998
• Status: Expired due to Term

• Current Assignee: Milwaukee Electric Tool Corporation (Techtronic Industries Company Limited)
• Original Assignee: Milwaukee Electric Tool Corporation (Techtronic Industries Company Limited)
• Inventors: Crisp, Robert, Willhide, Joseph, Glasgow, Kevin, Spence, Glen C.
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US09/672,620
• Time in Patent Office: 725 Days
• Field of Search: 320/106, 320/110, 320/128, 320/134, 320/136, 320/150
• US Class Current: 320/106
• CPC Class Codes: H02J 2207/40 adapted for charging from various sources, e.g. AC, DC or multivoltage
• CPC Class Codes: H02J 7/00038 using passive battery identification means, e.g. resistors or capacitors identification by mechanical connections H02J7/0045
• CPC Class Codes: H02J 7/00041 in response to measured battery parameters, e.g. voltage, current or temperature profile
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence

Abstract

A battery charger, a method for charging a battery, and a software program for operating the battery charger. The battery charger is capable of charging different types of batteries and capable of operating on alternate sources of AC power or alternate sources of DC power. Also, the battery charging circuit will not operate if one of the power source, the battery, the power switch means and the control means (including the Microcontroller) malfunctions. In addition, in the battery charging circuit, the battery under charge enables the operation of the battery charging circuit.

Claims

1. A battery charger comprising:

a battery charging circuit connectable to a power source and to a battery and operable to charge the battery; and

a Microcontroller electrically connected to and for operating said circuit, the battery, when connected to said circuit, supplying power to operate said Microcontroller.

2. The charger as set forth in claim 1 wherein the battery is chargeable to a charged state having a charged voltage of at least 5 volts, wherein, when the battery is connected to said circuit and in a depleted state having a voltage of less than 5 volts, said Microcontroller is supplied with the depleted state voltage of less than 5 volts and operates said circuit to charge the battery.

3. The charger as set forth in claim 2 wherein, when the battery is connected to said circuit and in the depleted state having a voltage of less than 3 volts, said Microcontroller is supplied with the depleted state voltage of less than 3 volts and operates said circuit to charge the battery.

4. The charger as set forth in claim 1 wherein said battery charging circuit is electrically connectable to an AC power source to charge the battery.

5. The charger as set forth in claim 1 wherein said battery charging circuit is electrically connectable to a DC power source to charge the battery.

17. The charger as set forth in claim 1 and further comprising a power switch to control a transfer of power from the power source to the battery in response to a control signal generated by said Microcontroller, and wherein the battery, when connected to said circuit, supplies power to power said power switch.

6. A method for operating a battery charger, the battery charger including a battery charging circuit connectable to a power source and to a battery and operable to charge the battery, and a Microcontroller electrically connected to and for operating the circuit, said method comprising the acts of:

providing a battery;

connecting the battery to the circuit; and

supplying power from the battery to the Microcontroller to operate the Microcontroller.

7. The method as set forth in claim 6 and further comprising the act of electrically connecting the circuit to the power source.

8. The method as set forth in claim 7 wherein said electrically connecting act includes electrically connecting the circuit to an AC power source.

9. The method as set forth in claim 7 wherein said electrically connecting act includes electrically connecting the circuit to a DC power source.

10. The method as set forth in claim 6 wherein the battery is chargeable to a charged state having a charged voltage of at least 5 volts, wherein, when the battery is connected to said circuit and in a depleted state having a voltage of less than 5 volts, said supplying act includes supplying the depleted state voltage of less than 5 volts from the battery to the Microcontroller to power the Microcontroller such that the Microcontroller operates the power switch means to charge the battery.

11. The method as set forth in claim 10 wherein, when the battery is connected to said circuit and in the depleted state having a voltage of less than 3 volts, said supplying act includes supplying the depleted state voltage of less than 3 volts from the battery to the Microcontroller to power the Microcontroller such that the Microcontroller operates the power switch means to charge the battery.

12. A combination for charging a battery, said combination comprising:

a battery;

a power source;

a battery charging circuit connectable to the power source and to the battery and operable to charge the battery; and

a Microcontroller electrically connected to and for operating the circuit, the battery, when connected to the circuit, supplying power to operate the Microcontroller.

13. The combination as set forth in claim 12 wherein the battery is chargeable to a charged state having a charged voltage of at least 5 volts, wherein the battery, when connected to the circuit and when in a depleted state having a voltage of less than 5 volts, supplies the depleted state voltage of less than 5 volts to operate the Microcontroller.

14. The combination as set forth in claim 13, wherein the battery, when connected to the circuit and when in a depleted state having a voltage of less than 3 volts, supplies the depleted state voltage of less than 3 volts to operate the Microcontroller.

15. The combination as set forth in claim 12 wherein the power source is an AC power source.

16. The combination as set forth in claim 12 wherein the power source is a DC power source.

18. A method of charging a battery, the method comprising the acts of:

providing a battery charger having a Microcontroller and a terminal;

electrically connecting the battery charger to a power source;

electrically connecting the battery to the terminal of the battery charger;

activating the Microcontroller in response to electrically connecting the battery to the terminal of the battery charger; and

transferring power from the power source to the battery in response to activating the Microcontroller.

19. The method as set forth in claim 18 wherein the act of activating the Microcontroller occurs after the act of electrically connecting the battery charger to the power source.

20. The method as set forth in claim 18 wherein the act of activating the Microcontroller includes the act of powering the Microcontroller with power from the battery.

21. The method as set forth in claim 20 wherein the act of powering the Microcontroller includes the act of powering the Microcontroller with a battery voltage of less than five volts.

22. The method as set forth in claim 21 wherein the act of powering the Microcontroller includes the act of powering the Microcontroller with a battery voltage of less than three volts.

23. The method as set forth in claim 21 wherein the act of transferring power from the power source to the battery charges the battery to a charged voltage of at least five volts.

24. The method as set forth in claim 18 wherein the act of activating the Microcontroller includes the acts of

enabling a switch with power from the battery in response to electrically connecting the battery to the terminal of the battery charger, and

powering the Microcontroller with power from the power source in response to enabling the switch with power from the battery.

25. The method as set forth in claim 24 wherein the act of enabling a switch includes the act of enabling the switch with a battery voltage less than five volts.

26. The method as set forth in claim 25 wherein the act of transferring power from the power source to the battery charges the battery to a charged voltage of at least five volts.

27. The method as set forth in claim 26 wherein the act of enabling a switch includes the act of enabling the switch with a battery voltage less than two volts.

28. The method as set forth in claim 18 wherein the act of electrically connecting the battery charger to a power source includes electrically connecting the battery charger to a direct current power source.

29. The method as set forth in claim 28 wherein the act of electrically connecting the battery charger to a power source includes electrically connecting the battery charger to a vehicle battery.

30. The method as set forth in claim 28 wherein the act of electrically connecting the battery charger to a power source includes electrically connecting the battery charger to a alternating current power source.

31. The method as set forth in claim 18 wherein the charger is operable to charge a first type of battery and a second type of battery, and wherein the method further comprises, prior to the act of transferring power:

identifying the chemistry of the battery; and

providing a signal to the Microcontroller identifying the chemistry of the battery.

32. The method as set forth in claim 18 wherein the battery charger includes a power switch to control the transfer of power from the power source to the battery in response to a control signal, wherein the method further comprises powering the power switch in response to electrically connecting the battery to the terminal of the battery charger, and wherein the act of transferring power includes controlling the power switch with a control signal from the Microcontroller.

33. The method as set forth in claim 32 wherein the act of activating the power switch includes the act of powering the power switch with power from the battery.

34. A battery charger for charging a battery with power from a power source, the battery charger comprising:

an input terminal electrically connectable to the power source;

a power switch electrically connected to the input terminal and operable to controllably transfer power from the power source to the battery in response to receiving a control signal;

an output terminal electrically connected to the power switch and electrically connectable to the battery; and

a controller electrically connected to the power switch and to the output terminal, the controller being powered by the battery and being operable to generate the control signal in response to being powered.

35. The battery charger as set forth in claim 34 wherein the battery charger charges the battery from a depleted state having a depleted-state voltage to a non-depleted state, and wherein the controller is operable to be powered by the battery having the depleted-state voltage.

36. The battery charger as set forth in claim 35 wherein the depleted-state voltage is less than five volts.

37. The battery charger as set forth in claim 35 wherein the depleted-state voltage is less than three volts.

38. The battery charger as set forth in claim 34 and further comprising a switch driver electrically connected to the power switch and the Microcontroller, wherein the control signal generated by the Microcontroller is a first control signal, wherein the power switch receives the first control signal and generates a second control signal in response to the first control signal, and wherein the power switch receives the second control signal and transfers power from the power source to the battery in response to receiving the second control signal.

39. The battery charger as set forth in claim 38 wherein the Microcontroller powers the switch driver.

40. The battery charger as set forth in claim 39 further comprising a voltage tripler electrically connected to the Microcontroller and to the switch driver, wherein the Microcontroller generates a power signal having a first voltage, wherein the voltage tripler receives the power signal from the Microcontroller and increases the power signal to a second voltage, and wherein the power signal having the second voltage powers the switch driver.

41. The battery charger as set forth in claim 34 wherein the power source is an alternating current power source.

42. The battery charger as set forth in claim 34 wherein the power source is a direct current power source.

43. A combination for charging a battery, the combination comprising:

a battery; and

a battery charger including

a power switch electrically connectable to a power source and connected to the battery, the power switch being operable to controllably transfer power from the power source to the battery in response to a control signal, and

a Microcontroller electrically connected to the battery and to the power switch, the Microcontroller being powered by the battery and being operable to generate the control signal when being powered.

44. The combination as set forth in claim 43 wherein the battery charger charges the battery from a depleted state having a depleted-state voltage to a non-depleted state, and wherein the controller is operable to be powered by the battery having a depleted-state voltage.

45. The combination as set forth in claim 44 wherein the depleted-state voltage is less than five volts.

46. The combination as set forth in claim 44 wherein the depleted-state voltage is less than three volts.

47. The combination as set forth in claim 44 wherein the Microcontroller further comprises a switch driver electrically connected to the power switch and to the Microcontroller, wherein the control signal generated by the Microcontroller is a first control signal, wherein the power switch receives the first control signal and generates a second control signal in response to the first control signal, and wherein the power switch receives the second control signal and transfers power from the power source to the battery in response to receiving the second control signal.

48. The combination as set forth in claim 44 wherein the Microcontroller powers the switch driver.

49. The combination as set forth in claim 44 wherein the battery charger further comprises a voltage tripler electrically connected to the Microcontroller and the switch driver, wherein the Microcontroller generates a power signal having a first voltage, wherein the voltage tripler receives the power signal from the Microcontroller and increases the power signal to a second voltage, and wherein the power signal having a second voltage powers the switch driver.