Electrical circuit system including voltage detector to selectively halt operation of an electrical circuit

• US 5,659,206 A
• Filed: 12/09/1994
• Issued: 08/19/1997
• Est. Priority Date: 12/13/1993
• Status: Expired due to Fees

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Taguchi, Fumiya, Sato, Kouji
• Primary Examiner(s): Shoop, Jr., William M.
• Assistant Examiner(s): LOCKETT, KIMBERLY R
• Application Number:
  US08/354,869
• Time in Patent Office: 984 Days
• Field of Search: 307/11, 307/12, 307/24, 307/32, 307/34, 307/31, 307/39, 307/86, 307/64, 307/66
• US Class Current: 307/11
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: H02J 9/061 for DC powered loads
• 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

An electrical circuit has a power source line from a battery. The power source line is divided into a primary side and a secondary side by a device, such as, for example, a diode. A high current load circuit is connected to the primary side and a lower current device, such as, for example, a display-related circuit and a capacitor are connected to the secondary side. The display-related circuit continues to receive adequate power when the battery voltage drops due to operation of the high current load circuit. In addition, a voltage detector is connected to the secondary side, where the voltage fluctuates less than on the primary side. The voltage detector controls operation of the high current load circuit. As a result, the high current load circuit can be efficiently driven.

Claims

1. An electrical circuit comprising:

a D.C. power source;

a power source line connected to said D.C. power source;

means for dividing said power source line into a primary side and a secondary side so that current may flow freely from said primary side to said secondary side but not from said secondary side to said primary side;

a high current load circuit connected to said primary side;

a secondary circuit connected to said secondary side, said secondary circuit drawing less current than said high current load circuit, said secondary circuit including electrical charge storage means; and

means for halting operation of said high current load circuit when a voltage across said secondary circuit decreases to a first value.

2. The electrical circuit of claim 1, wherein said electrical charge storage means provides current to said secondary circuit when the voltage across said secondary circuit decreases.

3. The electrical circuit of claim 2, further comprising means for starting operation of said high current load circuit when the voltage across said secondary circuit increases above a second value which is larger than or equal to said first value.

4. The electrical circuit of claim 1, further comprising means for starting operation of said high current load circuit when the voltage across said secondary circuit increases above a second value which is larger than or equal to said first value.

5. An electrical circuit comprising:

a battery;

a power source line connected to said battery;

a primary circuit that requires a first amount of current to operate, said primary circuit connected to said battery via said power source line;

a secondary circuit that is connected to said battery via said power source line, said secondary circuit requiring less current to operate than said primary circuit and including an electrical charge storage device;

a power source line dividing device that divides said power source line between said primary circuit and said secondary circuit so that current may flow freely through said power source line from said battery to said secondary circuit but not from said secondary circuit to said primary circuit;

a voltage detector that detects the voltage of the power source line at a side of said power source line dividing device containing said secondary circuit; and

a controller connected to said voltage detector, said controller halting operation of said primary circuit when the detected voltage decreases to a first value.

6. The electrical circuit of claim 5, wherein said electrical charge storage device comprises a capacitor.

7. The electrical circuit of claim 5, wherein said electrical charge storage device provides current to said secondary circuit when said voltage in said power source line decreases.

8. The electrical circuit of claim 5, wherein said controller starts operation of said high current load circuit when said detected voltage increases above a second value which is larger than or equal to said first value.

9. The electrical circuit of claim 5, wherein said primary circuit includes at least a magnet driving circuit.

10. The electrical circuit of claim 5, where said primary circuit includes at least a motor driving circuit.

11. The electrical circuit of claim 5, wherein said primary circuit includes at least a camera strobe charging circuit.

12. The electrical circuit of claim 5, wherein said power source line dividing device includes a diode.

13. The electrical circuit of claim 5, wherein said secondary circuit includes at least an LED driving circuit.

14. The electrical circuit of claim 5, wherein said secondary circuit includes at least a memory integrated circuit.

15. The electrical circuit of claim 5, wherein said secondary circuit includes at least a microcomputer.

16. The electrical circuit of claim 5, wherein said secondary circuit includes at least a display circuit.

17. A method of driving an electrical circuit including a D.C. power source, a power source line connected to said D.C. power source, a dividing device that divides said power source line into a primary side and a secondary side so that current may flow freely from said primary side to said secondary side but not from said secondary side to said primary side, a high current load circuit connected to said primary side, and a secondary circuit connected to said secondary side, said secondary circuit including an electrical charge device, comprising the following steps:

(a) detecting a voltage across said secondary circuit; and

(b) halting operation of said high current load circuit when the detected voltage decreases to a first value.

18. The method of claim 17, further comprising the step of providing current to said secondary circuit from an electrical charge storage device in said secondary circuit when the voltage across said secondary circuit decreases.

19. The method of claim 17, further comprising the step of starting operation of said high current load circuit when the voltage across said secondary circuit increases above a second value which is larger than or equal to said first value.

20. The method of claim 18, further comprising the step of starting operation of said high current load circuit when the voltage across said secondary circuit increases above a second value which is larger than or equal to said first value.