JP4375689B2 - Charger for small devices such as watches - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
This invention relates to a small device having a power generation function, such as a watch that rectifies AC electromotive force generated by a generator by a rectification unit, stores the rectified power in a power supply unit, and uses it as a power source for a clock unit. The present invention relates to a charging device for equipment.
[0002]
[Prior art]
In this type of charging device, in order to boost and store the generated electromotive force, it is disclosed in, for example, Japanese Patent Publication No. 61-15385 and Japanese Patent Laid-Open No. 10-282264, which performs boosting by chopper control. There is.
[0003]
In the former case, the voltage at the output terminal of the step motor coil is boosted by chopper control.
[0004]
In the latter case, the switch unit that short-circuits the output terminal of the power generation unit is chopper-controlled to boost the voltage, and the boosted power is charged. Further, the chopper operation is controlled by detecting the electromotive voltage using a comparator, that is, the chopper control is performed when the electromotive voltage is below a certain level, and the chopper control is not performed when the electromotive voltage is above a certain level.
[0005]
[Problems to be solved by the invention]
However, conventionally, since both ends of the coil are short-circuited and chopper-controlled, half-wave rectification is generally used for input to the charging circuit. In the case of full-wave rectification, the latter Japanese Patent Laid-Open No. 10-282264 is used. A complicated chopper control having an output synchronization circuit as disclosed in Japanese Patent Publication No. H11-228 was necessary. Also in the case of half-wave rectification, it is necessary to take reverse current prevention means such as a chopper control transistor or FET, which is a constraint condition of the chopper control unit.
[0006]
In addition, the method of detecting the generated voltage in JP-A-10-282264 and controlling the chopper operation is based on a comparator, and for a power generation system for a watch that has a power generation amount of several μA, It was difficult to use.
[0007]
A first object of the present invention is to provide a charging device for a small device such as a timepiece capable of improving charging efficiency and performing highly efficient charging.
[0008]
A second object is to provide a charging device for a small device such as a watch that can perform optimal charging with respect to fluctuations in the power generation state of the generator.
[0009]
The third object is to provide a charging device for small equipment such as a watch that can always perform optimum charging.
[0010]
[Means for Solving the Problems]
In order to achieve the above first and second objects, the present invention rectifies the AC electromotive force generated by the generator by the rectification unit, stores the rectified power in the power source unit, and uses it as a power source for the clock unit. In charging devices for small devices such as watches,
Chopper control means for chopper-controlling the voltage after rectification by periodically turning on and off the output terminal of the rectification unit at the switch unit is provided at the subsequent stage of the rectification unit, and the power boosted by the chopper control is supplied to the power supply unit While storing electricity ,
Power generation frequency detection means for detecting the power generation frequency from the on / off time of the inverter that is turned on / off by one voltage of the switch unit,
The chopper control means controls the on / off cycle of the switch unit according to the power generation frequency .
[0011]
To achieve the second object, Ru includes a power generation detecting means for detecting the presence or absence of power generation by the inverter to turn on and off by the voltage of one of the switch unit.
[0012]
In order to achieve the third object, rectification switching means for switching the rectification unit between half-wave rectification and full-wave rectification according to the level of the power generation frequency is provided.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings.
[0014]
FIG. 1 is a block diagram showing the configuration of a timepiece charging apparatus according to the present invention. The timepiece charging apparatus includes a generator 1, a rectifying unit 2 that rectifies an AC electromotive force generated by the generator 1, a switch unit 3 that periodically turns on and off the output terminal of the rectifying unit 2, and a charging unit. A power supply unit 5 including a capacitor or a secondary battery 4, a clock unit 7 including a clock circuit 6, an inverter 8 that is turned on / off by one voltage of the switch unit 3, and a reference signal generation that generates a reference signal A circuit 9, a first waveform synthesis circuit 10 which is a power generation presence / absence detection means for detecting the presence / absence of power generation of the generator 1 by the inverter 8, and a power generation frequency detection means for detecting the power generation frequency from the on / off time of the inverter 8. A second waveform synthesis circuit 11, a third waveform synthesis circuit 12 that is a chopper control means for performing chopper control from the power generation frequency and the reference signal, and the level of the power generation frequency It is composed of a rectifier switching section 13 for switching the rectifier 2 to the half-wave rectification and full-wave rectification.
[0015]
Next, the operation will be described.
The AC electromotive force generated by the generator 1 is half-wave rectified or full-wave rectified by the rectifier 2. The voltage after the rectification is periodically turned on / off by the switch unit 3 and chopper-controlled, whereby the voltage is boosted as shown in FIG. 2, and the boosted voltage is stored in the power source unit 5, and the clock unit 7 Used as a power source. FIG. 2 shows voltage waveforms at points (1) and (3) in FIG.
[0016]
On the other hand, the inverter 8 determines whether or not the generator 1 generates power, and inputs the determination signal to the first waveform synthesis circuit 10. The first waveform synthesis circuit 10 outputs a power generation state signal and a non-power generation state signal to the second waveform synthesis circuit 11 based on the reference signal from the reference signal generation circuit 9 and the determination signal. FIG. 3 shows waveforms at points (4) and (6) in FIG. 1 when the measurement range is 5 msec.
[0017]
The second waveform synthesis circuit 11 determines the power generation frequency based on the on / off time length of the signal from the first waveform synthesis circuit 10, and outputs a signal indicating that the power generation state has a predetermined power generation frequency. To the waveform synthesis circuit 12. FIG. 4 shows waveforms at points (4), (6) and (8) in FIG. 1 when the measurement range is 20 msec.
[0018]
The third waveform synthesis circuit 12 determines the on / off state of the chopper control from the signal from the second waveform synthesis circuit 11 and the reference signal from the reference signal generation circuit 9, and outputs from the reference signal generation circuit 9. The chopper signal is controlled according to the reference signal, and an on / off signal is output to the switch unit 3.
[0019]
At the same time, in synchronization with the chopper control signal, the rectification switching unit 13 is controlled according to the power generation frequency. That is, the rectification unit 2 is half-wave rectified when the power generation frequency is high, and full-wave rectification when the power generation frequency is low. FIG. 5 shows the waveform at point (9) in FIG.
[0020]
When the rectification method is switched according to the power generation frequency, highly efficient charging according to the power generation frequency can be performed. FIG. 6 shows the relationship between the power generation frequency by the rectification method and the charging energy.
[0021]
By the way, in the example mentioned above, the case where the charging device by this invention was applied to the timepiece was demonstrated. However, the present invention can be applied not only to a timepiece but also to other small device charging devices.
[0022]
【The invention's effect】
The effects of the present invention are as follows for each claim.
<Claim 1>
Since chopper control is performed at the subsequent stage of the rectification unit, rectification is possible only by a combination of diodes.
It is not necessary to prevent backflow in the switch section. Therefore, the charging current input to the power supply unit can be directly measured at the terminal of the switch unit, the restriction condition for chopper control is eliminated, and the voltage detection is facilitated.
There are no restrictions on full-wave / half-wave and rectification methods. In particular, full-wave rectification has a simple configuration and can provide a full-wave chopper-controlled charging device that is easy to use.
Since the power generation frequency is detected from the on / off time of the inverter that is turned on / off by one of the voltages of the switch section, optimal charging can be performed with respect to fluctuations in the power generation state of the generator.
Since the ON / OFF cycle of the switch unit is controlled according to the power generation frequency, more efficient charging can be realized.
[0023]
<Claim 2>
Since the presence or absence of power generation is detected by an inverter that is turned on / off by one voltage of the switch section, the power generation state can be detected with a very simple configuration, the overall system configuration is simplified, and a comparator, etc. Since a circuit with large current consumption is not required, the power consumption of the control unit can be reduced.
[0026]
<Claim 3 >
For example, when power is generated using a rotor weight, when the power generation frequency is high, half-wave rectification reduces the power generation load of the rotor weight, which increases the operating speed of the rotor weight and increases the power generation efficiency. Conversely, when the power generation frequency is low, the electromotive force is small and chopper control is required. Furthermore, full-wave rectification is preferable in order to charge a minute current without waste. Therefore, if the rectification unit is switched between half-wave rectification and full-wave rectification according to the level of power generation frequency, optimum charging can always be performed.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a timepiece charging device according to the present invention;
FIG. 2 is a voltage waveform diagram at points (1) and (3) in FIG.
FIG. 3 is a waveform diagram at points (4) and (6) in FIG. 1 when the measurement range is 5 msec.
4 is a waveform diagram at points (4), (6), and (8) in FIG. 1 when the measurement range is 20 msec.
FIG. 5 is a waveform diagram at point {circle around (9)} in FIG. 1;
FIG. 6 is a graph showing the relationship between the power generation frequency by the rectification method and the charging energy.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Generator 2 Rectification part 3 Switch part 4 Capacitor or secondary battery 5 Power supply part 6 Clock circuit 7 Clock part 8 Inverter 9 Reference signal generation circuit 10 1st waveform synthesis circuit 11 2nd waveform synthesis circuit 12 3rd waveform synthesis Circuit 13 Rectification switching part

Claims (3)

In the charging device for small appliances that rectifies the AC electromotive force generated by the generator at the rectifying unit, stores the electric power after the rectification in the power source unit, and uses it as the power source of the clock unit,
Chopper control means for chopper-controlling the voltage after rectification by periodically turning on and off the output terminal of the rectification unit by a switch unit is provided at the subsequent stage of the rectification unit, and the power boosted by the chopper control is supplied to the power source And storing electricity in the
A power generation frequency detecting means for detecting a power generation frequency from an on / off time of an inverter that is turned on / off by one voltage of the switch unit;
The charging device for a small device such as a timepiece, wherein the chopper control means controls an on / off cycle of the switch unit according to a power generation frequency .   The charging device for a small device such as a timepiece according to claim 1, further comprising a power generation presence / absence detecting means for detecting the presence / absence of power generation by an inverter that is turned on / off by one voltage of the switch unit. The charging device for small equipment such as a timepiece according to claim 1 or 2 , further comprising rectification switching means for switching the rectification unit between half-wave rectification and full-wave rectification according to the level of power generation frequency.

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