JPS6212399A - Operating method of stepping motor - Google Patents

Abstract

PURPOSE:To control a device to be controlled as prescribed in a wide frequency range by accurately calculating a resonance range in response to the operating state except the range, i.e., temperature and load. CONSTITUTION:A driving voltage, a temperature and a load are detected and input to a controller. The controller calculates a resonance range from the pieces of information and stored data, and so controls as to apply a step voltage so as to operate in a frequency range to avoid the resonance range. When the driving voltage is constant and at least one of the temperature and the load is varied or the driving voltage is altered, the resonance range is calculated at every time to alter the frequency range which cannot be used.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of operating a step motor, and more particularly, to a method of operating a step motor used as an actuator for controlling the operation of target equipment while avoiding a resonance region. be.

As is well known, a step motor is a device that rotates a rotor containing a permanent magnet or a magnetic material forward and backward in steps by converting an input pulse into a step waveform and applying it to the windings of a stator. It is widely used as an actuator to control the operation of various types.

In such step motors, there is a resonance region, that is, a frequency range in which the rotor operates unreliably due to inertia, etc., so countermeasures such as installing a damper to absorb the resonance or operating the motor to avoid the resonance region are taken. However, among these methods, the method of operation that avoids the resonance region is the simplest. However, the resonance region differs depending on the drive voltage of the step motor, the usage environment, etc., and the conventional method of centrally setting the resonance region by assuming all conditions in advance results in a significantly wide (unusable) region. The frequency range that can be used becomes extremely narrow, resulting in problems such as inconvenience in controlling the target equipment or the inability to perform the required control.

The present invention enables operation in a wide frequency range by detecting the operating state of the step motor and calculating the resonance region each time, and detects the drive voltage or drive xi, temperature, and load of the step motor. The above-mentioned problem is solved by configuring the system so that the information is input to an electronic control device, the resonance area is calculated based on this information, and operation is performed in a frequency range other than the calculated resonance area. It was used as a means to

Example An embodiment of the present invention will be described based on the drawings.

The drive voltage emitted from the power supply 12 through the power supply line 18 is controlled by the control signal voltage emitted from the output end of the electronic control unit (electronic control unit) 11 through the control line 17 to the step motor 1.
3 is applied as a step voltage to a predetermined winding. For example, in the case of a step motor with a bifilar winding 4-phase structure, the on/off operation of the power transistor to which the drive voltage and control signal voltage are applied causes one of the four phases in total of two pairs of two-phase windings to be activated. A step voltage is applied, and when operated by the two-phase excitation method, either two
The applied phase is the same as a conventional step motor.

A temperature sensor 14 is installed near or (and) inside the step motor 13, and a load sensor 15 for the step motor 13 is installed.
The electric signal continuously emitted by 5 is sent to the % converter 16 through signal lines 19 and 20, and the driving voltage is sent to the % converter 16 through a signal line 21 branched from the power line 18.

Here, each piece of information converted into a digital signal is input to the control device 11.

The internal memory of the control device 11 stores information such as the resonance region at the drive voltage, the temperature at that drive voltage, and changes in the resonance region due to load fluctuations (this is stored for each drive voltage value). The resonance region is set in advance through experiments.

While the step motor 13 is in operation, its driving voltage, temperature, and load are almost continuously input to the control device 11, and a resonance area is calculated from this information and stored data. The control signal voltage for applying the step voltage is controlled so that the operation is performed in a frequency range that avoids this. When the drive voltage is constant and the temperature and load are small (when one of them fluctuates, or when the drive voltage fluctuates, the resonance region at that time is calculated and the unusable frequency range is changed each time.

Note that the same effect can be achieved even if the above calculation is performed using the drive current instead of the drive voltage.

According to the present invention, the resonance region that can be determined by the drive voltage or drive current can be calculated more accurately according to other operating conditions, that is, temperature and load, and for this purpose, fine-grained data can be stored in the control device. By doing so, it becomes possible to avoid only the resonance region corresponding to the operating state at that time and operate in a wide frequency range, and when used as an actuator, it is possible to control the target equipment as specified.

[Brief explanation of drawings]

The drawing is a block diagram of an embodiment of the invention. 11...Control device, 12...Power supply, 1
3...Step motor, 14...Temperature sensor, 15...Load sensor.

Claims (1)

[Claims] The drive voltage or drive current, temperature, and load of the step motor are detected and input to the electronic control device, and based on this information, the resonance area is calculated and the operation is performed in a frequency range outside the calculated resonance area. A method of operating a step motor, characterized by causing the step motor to perform the following steps.