JPH1032989A - Drive device for vibration actuator - Google Patents

Abstract

(57) [Summary] [Object] To provide a driving device for a vibration actuator capable of obtaining a sufficient vibration force while being driven by a battery even if it is small and has a very small diameter. In a portable device that drives a vibration actuator by driving a battery, a booster circuit that converts a voltage of a built-in battery into a high voltage, a rectifier circuit that rectifies the high voltage and charges a charging capacitor. The vibration actuator 10 includes a power supply circuit 5 for supplying the electric charge charged in the charging capacitor 4 to the vibration actuator 10, and a switch unit for alternately performing a charging operation on the charging capacitor 4 and a power supply operation on the vibration actuator 10. DC voltage which is applied intermittently for a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving device for a vibration actuator in a portable electronic device having a vibration actuator such as a small vibration motor driven by a battery, a speaker-type vibration device, a plunger-type vibration device and the like.

[0002]

2. Description of the Related Art Conventionally, in a small pager (pager), a cellular phone, or the like, a vibrating device such as a pager or the like is used as a calling notification means during a meeting or in a hospital or the like where an alarm sound is transmitted. Some have built-in. If the mode is switched to the vibration mode in advance, the vibrator is driven instead of outputting an alarm sound when a call is received, and the call can be detected by the vibration. Generally, a small motor is used for such a vibrator, and an eccentric weight or the like is attached to a rotating shaft of the motor, and the motor is rotated by a battery to generate vibration.

As such a motor, a small vibration motor capable of rotating at a low voltage has been conventionally developed. Generally, a pager battery is an AA type or AAA type dry battery or a rechargeable battery, and the voltage is as high as at most. 1.2V ~ 1.5
About V. As a result, the motor is hardly started, and sometimes does not rotate even when the power is turned on.

For this purpose, a method of using a high-voltage power supply only at the time of starting so as to easily start rotation even at a low voltage as a motor and driving the motor with a low-voltage power supply after starting has been considered. When the battery voltage drops due to consumption, there is a problem that it is difficult to drive the rotation and a sufficient vibration force cannot be obtained. In particular, the recent trend is that ultra-small ultra-small diameter vibration motors have been required, and as the size has been reduced, the inertia of eccentric weights etc. has become smaller and easier to start. However, there is a problem that a large vibration force cannot be obtained.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and to provide a driving apparatus for a vibration actuator which can obtain a sufficient vibration force while being driven by a battery even if it is small in size and extremely small in diameter.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. In a portable device for driving a vibration actuator by driving a battery, the voltage of a built-in battery 1 is converted to a high voltage. A booster circuit 2; a rectifier circuit 3 for rectifying the high voltage to charge the charging capacitor 4; a power supply circuit 5 for feeding the electric charge charged in the charging capacitor 4 to the vibration actuator 10; Charging operation and vibration actuator
A switch unit for alternately performing a power supply operation to the power supply 10 is provided, and a boosted DC voltage is applied to the vibration actuator 10 intermittently for a short time.

[0007]

According to the vibration actuator driving device of the first aspect, the battery 1 as the original power supply has a low voltage, but is boosted to a high voltage by the boosting circuit 2 and charged in the charging capacitor 4. Therefore, by supplying power from the charging capacitor 4 to the vibration actuator 10 in a pulsed manner only for a short time, a small-sized vibration motor can be driven at the same high rotation as the high-voltage drive even with a low-voltage battery driven and a small power. Therefore, a large vibration force can be obtained. In addition, since the small vibration motor can be driven intermittently for pulse driving, vibration in various modes can be generated by changing the pulse interval, and the vibration can be easily detected.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a driving apparatus for a vibration actuator according to the present invention.

FIG. 1 is a block diagram showing an embodiment of a driving apparatus for a vibration actuator according to the present invention, FIG. 2 is a circuit diagram showing an embodiment of a driving apparatus for a vibration actuator according to the present invention, and FIG. 3 is a circuit shown in FIG. FIG. 4 is a waveform chart showing a control signal waveform and a terminal voltage of a vibration actuator in FIG.

In FIG. 1, a battery 1 built in a pager supplies power to a booster circuit 2 whose operation is controlled by a control signal A. The booster circuit 2 has a function of converting a voltage of 1.5 V of the battery 1 to a high voltage of 3 to 9 V, which is twice to six times.
The high voltage output of the booster circuit 2 is connected to one electrode of a charging capacitor 4 via a rectifier circuit 3 and to a power supply circuit 5. The operation of the power supply circuit 5 is controlled by the control signal B.

The two control signals A and B are supplied from a control signal generation circuit, and operate the booster circuit 2 and the power supply circuit 5 alternately and exclusively. In such a configuration, when the booster circuit 2 operates by the control signal A, a high voltage is generated at the output of the booster circuit 2, and the high-voltage charge is charged in the charging capacitor 4 via the rectifier circuit 3. Even if the booster circuit 2 stops operating due to the control signal A, the charge of the charging capacitor 4 does not flow back to the booster circuit 2 due to the operation of the rectifier circuit 3, so that the charging capacitor 4 remains biased at a high voltage. It is a state of.

Next, the power supply circuit 5 is operated by the control signal B to supply the electric charge charged in the charging capacitor 4 to the vibration actuator 10, and the charging capacitor 4 is charged.
Terminal voltage drops. Even if the power supply circuit 5 stops operating due to the control signal B, the terminal voltage of the charging capacitor 4 does not increase until the booster circuit 2 operates again. When the booster circuit 2 and the power supply circuit 5 operate alternately, the terminal voltage of the vibration actuator 10 becomes a DC rectangular wave.

FIG. 2 is a circuit diagram showing a specific embodiment of a vibration actuator driving device according to the present invention. In this circuit, the booster circuit 2 is composed of a blocking oscillator including a transformer having two windings 11 and 12, a capacitor 13, a transistor 14 and a resistor 15, and the battery 1 is used as a power source of the blocking oscillator. It is connected.
The control signal A is provided as the base bias voltage of the transistor 14, and when the control signal A is at a voltage level of approximately 1 volt or more, the blocking oscillator starts transmitting,
A pulse voltage of a voltage is generated at the collector of the transistor 14. When the control signal A falls below a voltage level of about 0.4 volts, the blocking oscillator stops emitting and the pulse voltage is not generated. At this time, the power consumption of the booster circuit 2 for the battery 1 is substantially zero.

A high-voltage pulse voltage generated at the collector of the transistor 14 of the booster circuit 2 is applied to the charging capacitor 4 via the rectifier circuit 8, and charges the charging capacitor 4 with electric charge. That is, the transistor 14 switched by the control signal A constitutes a switch for causing the charging capacitor 4 to perform a charging operation. The rectifier circuit 3 is a diode, and prevents the charge charged in the charging capacitor 4 from flowing back to the booster circuit 2. Therefore, the charging capacitor 4
Is supplied to the vibration actuator 10 only by the power supply circuit 5. This power supply circuit 5 has a resistor 16
18 and a transistor 17. Control signal B is provided as the base input of transistor 17, and when control signal B is at a voltage level of approximately
17 conducts and supplies the electric charge charged in the charging capacitor 4 to the vibration actuator 10 via the resistor 16. That is, the transistor 17 which is switched by the control signal B constitutes a switch means for performing a power supply operation to the vibration actuator 10. When control signal B is at a voltage level of about 0.4 V or less, transistor 17 is off. When the transistor 17 conducts, the resistor 16
It is used to control the current flowing from the battery 1 via the winding 11 of the booster circuit 2 and the rectifier circuit 3.

In such a circuit, control signals A and B
Is a pulse train voltage as shown in FIGS. 3A and 3B, respectively, the charging capacitor 4 is charged when the control signal A is 1.5V and discharged when the control signal B is 1.5V. Repeat the charge / discharge cycle, and
Is the DC pulse train voltage shown in FIG. By changing the frequency of this pulse train voltage,
Since the vibration actuator 10 can be driven intermittently, various modes of vibration can be generated, and the vibration can be easily sensed.

Further, since the two control signals A and B are configured to be active only when the vibration actuator is driven at the time of calling the pager, the control signals A and B are normally set to zero volts. Level, minimizing battery power consumption. Further, in the present invention, an example in which a transformer and a capacitor are used as the boosting circuit has been described, but a D / A converter or the like may be used. Further, in the present invention, as a vibration actuator, in addition to a small vibration motor, an actuator that requires switching, such as a speaker-type vibration device and a plunger-type vibration device, can be driven, so that it can be applied to a wide range of portable devices.

[0017]

According to the present invention, as described in detail in the embodiment, although the battery 1, which is the original power supply, has a low voltage, the battery 1 is boosted to a high voltage by the booster circuit 2 and charged into the charging capacitor. Since the charging capacitor supplies power to the coil of the small motor 4 by pulse driving only for a short time, the small vibration motor is driven at the same high rotation as the high voltage driving even with low voltage battery driving and small power. Large vibration force can be obtained. Further, since the small vibration motor can be driven intermittently for pulse driving, it is possible to generate vibrations in various modes by changing the pulse interval, and it is possible to provide a vibration actuator driving device which can easily detect the vibration.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a driving device for a vibration actuator according to the present invention.

FIG. 2 is a circuit diagram showing one embodiment of a vibration actuator driving device according to the present invention.

FIG. 3 is a waveform diagram showing a waveform of a control signal and a terminal voltage of a vibration actuator in the circuit of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery 2 Booster circuit 3 Rectifier circuit 4 Charging capacitor 5 Power supply circuit 10 Vibration actuator

Claims (1)

[Claims] 1. A portable device for driving a vibration actuator by driving a battery, comprising: a boosting circuit for converting a voltage of a built-in battery into a high voltage; a rectifying circuit for rectifying the high voltage to charge a charging capacitor; A power supply circuit for supplying the electric charge charged to the vibration capacitor to the vibration actuator; and a switch means for alternately performing a charging operation for the charging capacitor and a power supply operation for the vibration actuator. A driving device for a vibration actuator, wherein a DC voltage is applied intermittently for a short time.