Power-generating device, charging method and clocking device

• US 6,154,422 A
• Filed: 02/09/1998
• Issued: 11/28/2000
• Est. Priority Date: 02/07/1997
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Fujisawa, Teruhiko, Shinkawa, Osamu, Uetake, Akihito
• Primary Examiner(s): MISKA, VIT W
• Application Number:
  US09/020,702
• Time in Patent Office: 1,023 Days
• Field of Search: 368/64, 368/66, 368/203-205, 323/222, 323/282, 323/281, 323/288, 363/83, 363/89, 363/127, 320/166, 320/167, 320/101, 320/102
• US Class Current: 368/204
• CPC Class Codes: G04C 10/00 Arrangements of electric power supplies in time pieces circuits G04G19/00; mounting, assembling of components of electromechanical watches G04C3/008, of electronic watches G04G17/00
• CPC Class Codes: H02M 3/1552 Boost converters exploiting the leakage inductance of a transformer or of an alternator as boost inductor
• CPC Class Codes: H02M 7/217 using semiconductor devices only

Abstract

A power-generating device can include a dynamo for converting kinetic energy into electrical energy, a switch capable of short-circuiting output terminals of the dynamo, a controller capable of controlling the switch, a rectifier for rectifying an output of the dynamo, and a charging portion capable of storing the output of the dynamo. The controller can perform chopper control for cyclically turning on and off the switch in accordance with a PWM signal. Where an electromotive voltage of the dynamo is lower than a charged voltage, a boosted voltage can be produced by chopper amplification. If the electromotive voltage is low, it can be charged in the charging portion if the boosted voltage is increased to a sufficient level prior to charging.

Claims

1. A power-generating device comprising:

a power generator including a dynamo coil, said dynamo coil having at least two output terminals, said power generator generating an output induced in said dynamo coil, said output having a voltage;

a switch constructed to short-circuit said at least two output terminals of said dynamo coil;

a controller constructed to control said switch;

a rectifier constructed to rectify said output of said power generator to produce a rectified output;

a charging portion constructed to accumulate said rectified output; and

said controller having a chopper control function constructed to cyclically turn said switch on and off such that said output voltage may be selectively chopper-amplified.

2. The power-generating device according to claim 1, wherein said controller includes a polarity determiner constructed to determine the polarity of said output of said power generator.

3. The power-generating device according to claim 1, wherein said switch is constructed to permit current to flow in only one direction.

4. The power-generating device according to claim 1, wherein said rectifier is constructed to perform full-wave rectification by a combination of rectifier diodes and rectifier switches connected upstream and downstream of said at least two output terminals of said power generator, one of said two output terminals having a lower potential than the other;

and wherein said controller has a polarity determiner constructed to determine the polarity of said power generator voltage, and to permit said rectifier coupled to the lower potential of said output terminals to serve as said switch.

5. The power-generating device according to claim 1, wherein said rectifier includes a rectifier diode and a bypass switch constructed to bypass said rectifier diode.

6. A charging method for accumulating electric power generated by a power generator, the electric power being accumulated by a charging portion, said method comprising chopper-amplifying the output of the power generator where a power generator voltage is less than a voltage of said charging portion.

7. The charging method according to claim 6, wherein said chopper-amplification is produced by cyclically turning on and off a switch capable of short-circuiting output terminals of the power generator.

8. The charging method according to claim 7, wherein, in said chopper amplifying step, said switch is operated by using at least a portion of an oscillation signal of a clocking portion, wherein said clocking portion operates by electric power supplied by at least said charging portion.

9. A power-generating device comprising:

a power generator including a dynamo coil, said dynamo coil having at least two output terminals, said power generator generating an output induced in said dynamo coil, said output having a voltage;

a switch coupled to said power generator for short-circuiting said at least two output terminals of said dynamo coil;

a rectifier coupled to said power generator for rectifying the output of said power generator;

a charging portion coupled to said rectifier for accumulating an output from the rectifier; and

,

a controller coupled to said switch and performing a chopper control function for cyclically activating and deactivating said switch such that said output voltage may be selectively chopper-amplified.

10. The power-generating device according to claim 9, wherein said controller includes a polarity determiner coupled to said power generator for determining the polarity of said output of said power generator.

11. The power-generating device according to claim 9, wherein said switch is constructed to permit current flow in only one direction.

12. The power-generating device according to claim 9, wherein said rectifier is a full wave rectifier comprising a first and a second rectifier diode, each coupled to the high potential side of said at least two output terminals of said power generator, and a first and a second rectifier switch, each coupled to the lower potential side of said at least two output terminals of said power generator, and wherein said controller comprises a polarity determiner for determining the polarity of said power generator voltage and causing one of said first and second rectifier switches to function as said switch.

13. The power-generating device according to claim 9, wherein said rectifier includes a rectifier diode and a bypass switch for bypassing said rectifier diode.

14. A clocking device, comprising:

a power-generating device including;

a power generator including a dynamo coil, said dynamo coil having at least two output terminals, said power generator generating an output induced in said dynamo coil, said output having a voltage;

a switch coupled to said power generator for short-circuiting said at least two output terminals of said dynamo coil;

a rectifier coupled to said power generator for rectifying the output of said power generator;

a charging portion coupled to said rectifier for accumulating an output from the rectifier;

a controller coupled to said switch and performing a chopper control function for cyclically activating and deactivating said switch such that said output voltage may be selectively chopper-amplified; and

a clocking portion constructed to operate by electric power supplied from said charging portion.

15. The clocking device according to claim 14, wherein said clocking portion includes an oscillation signal, and wherein said controller performs said chopper function by using at least a portion of said oscillation signal of said clocking portion.

16. A clocking device, comprising:

a power-generating device including;

a power generator including a dynamo coil, said dynamo coil having at least two output terminals, said power generator generating an output induced in said dynamo coil, said output having a voltage;

a switch constructed to short-circuit said at least two output terminals of said dynamo coil;

a controller constructed to control said switch;

a rectifier constructed to rectify said output of said power generator to produce a rectified output;

a charging portion constructed to accumulate said rectified output;

said controller having a chopper control function constructed to cyclically turn said switch on and off such that said output voltage may be selectively chopper-amplified; and

,

a clocking portion constructed to operate by electric power supplied from said charging portion.

17. The clocking device according to claim 16, wherein said clocking portion includes an oscillation signal, and wherein said controller is constructed to perform said chopper control by using at least a portion of said oscillation signal of said clocking portion.

18. A power generating device comprising:

a power generator including a dynamo coil, said dynamo coil having at least two output terminals, said power generator generating an output induced in said dynamo coil, said output having a voltage;

a switch constructed to short-circuit said at least two output terminals of said dynamo coil;

a controller constructed to control said switch;

a rectifier constructed to rectify said output of said power generator to produce a rectified output;

a charging portion constructed to accumulate said rectified output; and

said controller having a chopper control function constructed to cyclically turn said switch on and off, wherein said controller includes a determiner constructed to determine the voltage of said power generator output, and to stop said chopper control function when said charging portion can be charged with said output of said power generator.

19. The power-generating device according to claim 18, wherein said determiner is constructed to compare said output voltage of said power generator with a voltage of said charging portion.

20. The power-generating device according to claim 18, wherein said determiner is constructed to compare said power generator output voltage with a first reference voltage, at which said power generator output voltage is deemed capable of charging said charging portion.

21. The power-generating device according to claim 18, wherein said determiner is constructed to determine said power generator output voltage by detecting a voltage drop in a power supply circuit with respect to said charging portion.

22. A power generating device comprising:

a power generator including a dynamo coil, said dynamo coil having at least two output terminals, said power generator generating an output induced in said dynamo coil, said output having a voltage;

a switch constructed to short-circuit said at least two output terminals of said dynamo coil;

a controller constructed to control said switch;

a rectifier constructed to rectify said output of said power generator to produce a rectified output;

a charging portion constructed to accumulate said rectified output; and

said controller having a chopper control function constructed to cyclically turn said switch on and off, wherein said controller includes a determiner constructed to determine a voltage of said charging portion and to activate said switch when said charging portion voltage exceeds a second setting voltage, beyond which said charging portion voltage is judged to be excessive.

23. A charging method for accumulating electric power by a charging portion, said electric power generated by a power generator, said method comprising chopper-amplifying the output of the power generator where a power generator voltage is less than a voltage of said charging portion, with said chopper-amplification being produced by cyclically turning on and off a switch capable of short-circuiting output terminals of the power generator, and turning on said switch when said voltage of said charging portion is deemed excessive.

24. A power-generating device comprising:

a power generator including a dynamo coil, said dynamo coil having at least two output terminals, said power generator generating an output induced in said dynamo coil, said output having a voltage;

a switch coupled to said power generator for short-circuiting said at least two output terminals of said dynamo coil;

a rectifier coupled to said power generator for rectifying the output of said power generator;

a charging portion coupled to said rectifier for accumulating an output from the rectifier; and

,

a controller coupled to said switch and performing a chopper control function for cyclically activating and deactivating said switch, wherein said charging portion includes a capacitor and said controller includes a determiner coupled to said power generator for determining the level of voltage of said power generator output and for ceasing said chopper control function when said voltage from said power generator is sufficient to charge said capacitor.

25. The power-generating device according to claim 24, wherein said determiner compares said output voltage of said power generator with a capacitor charged voltage accumulated by said capacitor, and cease said chopper control function when the value of said charged voltage is less than the output voltage of said power generator.

26. The power-generating device according to claim 24, wherein said determiner compares said power generator output voltage with a first reference voltage, and ceases said chopper control function when said power generator output voltage is greater than said first reference voltage.

27. The power-generating device according to claim 24, further comprising a power supply circuit wherein said determiner determines said power generator output voltage by detecting a voltage drop in the power supply circuit.

28. A power-generating device comprising:

a power generator including a dynamo coil, said dynamo coil having at least two output terminals, said power generator generating an output induced in said dynamo coil, said output having a voltage;

a switch coupled to said power generator for short-circuiting said at least two output terminals of said dynamo coil;

a rectifier coupled to said power generator for rectifying the output of said power generator;

a charging portion coupled to said rectifier for accumulating an output from the rectifier; and

,

a controller coupled to said switch and performing a chopper control function for cyclically activating and deactivating said switch, wherein said charging portion includes a capacitor and said controller includes a determiner, coupled to said capacitor and said switch, for determining a voltage of said capacitor and for activating said switch when said capacitor voltage exceeds a second reference voltage to protect said capacitor from an overvoltage.