JPH03247130A - Method for driving motor - Google Patents

Abstract

PURPOSE:To minimize weight and to make the motor compact in size by providing a voltage control circuit varying a voltage applied to the motor at a certain period and assisting the change in the speed of revolution of the motor to amplify the vibration caused by the rotation of the weight placed eccentrically. CONSTITUTION:The resistance of a resistor in a voltage control circuit 1 is varied periodically by using an external signal through a control terminal 1A to vary a voltage applied to the motor 4 as shown in waveform diagram in the Figure 3(a) with respect to time, thereby varying the speed of revolution and the angle of rotation of the motor. A voltage change in the motor for a period longer than that of a rotating angle 360 deg. (one period) is applied to the motor to allow the vibration caused by the drive of the weight placed eccentrically to be amplified.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for driving a motor used in an individual selective call receiver, and in particular, a method for supplying power to the motor based on a call signal, and a method for driving a motor attached to the motor shaft. The present invention relates to a method for driving a motor for generating vibrations using weights.

[Conventional technology]

Conventionally, the method for driving this type of motor is as shown in the block diagram of FIG. Rotate. Further, an eccentric weight is attached to the rotating shaft of the motor 4, and even if the motor rotates at a constant rotation speed, vibrations are generated due to the eccentric force of the weight.

[Problem to be solved by the invention]

In the conventional motor driving method described above, since the rotational speed of the motor is constant, obtaining the necessary vibration requires a large weight, which is a major obstacle to miniaturizing devices such as individual selective call receivers. There is a drawback. Furthermore, in order to make weights smaller, a substance with a higher specific gravity is used, which makes the weights more expensive. There is also the disadvantage that attaching a heavy weight increases the load on the motor body and shortens the life of the motor.

[Means to solve the problem]

The motor driving method of the present invention is a motor driving method in which an eccentric weight is attached to the rotating shaft of the motor to generate vibration, and a voltage that changes at an arbitrary period longer than the rotation period of the motor is applied to the motor. Alternatively, a voltage is applied to the motor such that the rotation speed of the motor changes in synchronization with the rotation angle of the motor.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of a first embodiment of the present invention.

The embodiment shown in FIG. 1 is the same as the conventional example, including a motor 4 with a weight attached eccentrically to the rotating shaft, a switch 2 that is turned on and off by a call signal 10, a power supply 3 for driving the motor 4, and a motor 4 connected to the motor 4. Voltage control circuit 1 that controls voltage
, is composed of.

Now, in this embodiment, if the resistance of the voltage control circuit 1 is changed periodically from the outside via the control terminal IA, and the voltage applied to the motor 4 is changed over time as shown in the waveform diagram of FIG. 3(a), The rotation speed and rotation angle of the motor are shown in Figure 3 (
b), the waveform changes as shown in the waveform diagram of FIG. 3(c). That is, by applying to the motor a voltage change with a cycle longer than the rotation angle of 360° (one cycle) of the motor, vibrations due to eccentricity of the weight increase. In this case, it is not preferable to change the voltage to the motor too quickly because excessive eccentric force will be applied.

Next, a second embodiment of the present invention will be described with reference to the configuration diagram of FIG. The difference from the first embodiment is that the voltage control circuit 1
The signal for the resistance change is obtained not from the outside but from the rotation angle signal 5 of the motor 4.

As a result, voltage control is performed almost in synchronization with changes in rotation angle due to eccentricity of the motor 4, so vibrations due to eccentricity of the weight increase within its own loop.

〔Effect of the invention〕

As explained above, by providing a voltage control circuit that changes the voltage applied to the motor in a certain period, the present invention has the effect of promoting changes in the rotational speed of the motor and amplifying vibrations caused by the rotation of the eccentric weight. . Therefore, in order to obtain the same vibration, the weight can be made smaller, so the motor can also be made smaller, which is effective in reducing the size and cost of the equipment used.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention, FIG. 2 is a block diagram of a second embodiment of the present invention, and FIG. 3(a). (b) and (c) are waveform diagrams of temporal changes in voltage, rotation speed, and rotation angle of the motor according to this embodiment, and FIG. 4 is a configuration diagram according to a conventional motor driving method. 1... Voltage control circuit, IA... Control terminal, 2... Switch, 3... Power supply, 4
...Motor, 5...Rotation angle signal, 1
0...Call signal.

Claims (1)

[Claims] In a motor driving method that generates vibration by attaching an eccentric weight to the rotating shaft of the motor, a voltage that changes at an arbitrary period longer than the rotation period of the motor is applied to the motor, or A method for driving a motor, characterized in that a voltage is applied to the motor so that the rotation speed of the motor changes in synchronization with the rotation angle.