JPS6082084A - Controller for plural dc motors - Google Patents

Abstract

PURPOSE:To enable to control a fast responsiveness stably with less variation in the rotating speed by selecting the frequency of an encoder to substantially constant for the preset rotating speed, thereby maintaining the control times of motors constant. CONSTITUTION:A signal of frequency corresponding to the rotating speed is outputted from encoders EA, EB, EC upon rotating of a motor. A data selector DS selects one of signals from the encoders EA, EB, EC by a signal from a controller CTRL, and outputs an interrupt signal INTO to the controller CTRL. The entire controller MPU compares the preset values of the rotating speeds of motors with the actual rotating speed measured from an encoder signal, and outputs data of duty for energizing motors to drivers DRIVEA-C of motors EA, EB, EC.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a rotation speed control device for a plurality of DC mode machines, and particularly to a control device for a plurality of DC mode machines suitable for use in a copying machine or the like.

[Background of the invention]

Conventionally, the number of generated pulses was the same even when multiple encoders were attached to the mode.
For example, if the set rotational speed is twice that of the other, the output encoder frequency will also be doubled. Since the rotation speed of multiple modes is detected by switching one counter, the rotation speed detection time of a mode with a low frequency is
The frequency is doubled for a mode with a high frequency, and the time required to move on to detecting other modes is correspondingly delayed. When controlling multiple models, the control time for multiple models is different, and The control is not the same, and there is a drawback that the control device has poor follow-up performance such as a decrease in the rotation speed due to large rotation speed fluctuations, a delay in response to load fluctuations, etc.

[Purpose of the invention]

This invention makes the control time of multiple moders approximately the same by making the output frequencies of the encoders approximately the same.
To provide a control device for a plurality of DC moders that has good followability and can provide almost the same performance for a plurality of modes.

[Summary of the invention]

In the present invention, encoders are selected and used so that the output frequencies of the encoders are approximately the same even at the preset rotational speed of several rM models.

[Embodiments of the invention]

The operation of the control device of the present invention will be explained with reference to FIG. In this example, there are three models M A 1M! l 1Me
This is for the case where the rotation speed is controlled at the same time. Eight encoders r EB Hhc are respectively attached to the moders MA, Ml, and Me. As the model rotates, the encoder outputs a signal with a frequency proportional to the number of rotations, as shown in an example in FIG. 2EA. Ds is a data selector and overall control & KM
The encoder Eh is activated by a signal from the control unit CTR,L in the PU.

Select No. 46 of 1') from the signals in E++ and EcoO,
As shown in the interrupt signal INT in FIG. 2, a pulse signal synchronized with the rising edge of the encoder signal is output to the control unit CTRL as the interrupt signal INT.

The overall control device αMPU compares the value of the rotation speed of each mode set in advance with the actual rotation speed determined through the DS (7) and the incoming encoder signal, and Rotate motors EA and EB so that their rotation speeds are exactly the same as the preset rotation speed.

EC's)"/'iver device MDRIVA, J) RIVB
.

i) Duty booter output through which goes to R, IVCK motor. DI-IIVA-DRIVC is the whole t
Transistor QA according to data from lilJ controller MPU.

Turn on Q, , Qc for a certain period of time.

In this way, the modal M~Me is QA-Qc's "On 1".
The rotation speed is controlled by 1I71J based on the time, that is, the duty value. For example, if the rotation speed of the moder EA is lower than the preset rotation speed, the MPU will
1 shift of data that keeps QA "on" for a longer time is output to increase the rotation speed of moder EA.

Here, V is the electrolytic corrosion for driving the model.

Here, the encoder frequency combinations of the present invention will be explained in detail. First, with reference to FIG. 2, a method for detecting the moder rotational speed will be explained. It is now assumed that the data selector DS selects the encoder frequency number. The data selector DS outputs a pass signal INT synchronized with the rising edge of the Em signal as an interrupt signal to the control unit CTRL in the MPU. The CTR, L section measures the time from the first I NT signal to the second INT signal by using a counter CNTR to measure the number of pulses from the oscillator CK (for example, composed of a crystal oscillator X, etc.). . Although this time is inversely proportional to the number of rotations of the moder, the number of rotations of the modele can be determined by measuring the time.

After measuring the rotation speed of modele MA, CTRL then outputs a signal to DS to select encoder EB,
The rotation speed of the moder MB is measured in the same manner as described above, and then the rotation speed of the moder Me is determined 6111 in the same manner. The measured rotation speed and the preset rotation speed are compared by the calculation unit ALU, and each motor is turned on.
Output time data values.

In this way, the number of rotations is measured by changing the nuclear number encoder EA ``'' E c signal, so EA + E
If the frequencies of the n+Ec signals are different, the interval t of the INT signal will be different, so the rotational speed f of each moder: the time at which it starts to rise will be different.

Further, as shown in FIG. 3, the interrupt signal INT is EA.

L and EA are generated by the rising edges of Ee and Ec.

Since Es, Ec and other signals are not synchronized, for example, L B
Even if EB or other signals are selected with the J selection signal, INT is activated by EB.
As shown in the figure, in the worst case, the signal will be delayed by the time between INT and INT. In other words, twice the time t between INT and INT is required.

For example, if the encoder frequency becomes 172,
The time required to measure the rotational speed also doubles, and a delay of %1fflJ# occurs from this time e.

According to the present invention, the frequencies of the encoders EA, En, and Ec are selected to be almost the same with respect to the preset rotation speed, so the time t between INT and INT is
is almost constant, and the control time of each mode is constant, so t is stable, has little variation in rotation speed, and has quick response.
ljlJ control becomes possible.

Also, since the input signal INT signal to CTRL is an interrupt signal, the MPU inputs the first INT signal and the second I
Since the rotation speed is measured by comparing the CNTR value when the NT signal is input, another control can be performed when the INT signal is not input.

Furthermore, if the preset rotation speed is doubled, for example, the IN'l' signal will arrive in 1/2 the time compared to before, but in this case, the INT
By counting the signals, the number of rotations can be detected from the first to the third INT time (after roasting, the number of rotations can be detected at approximately the same time).

〔Effect of the invention〕

According to the present invention, since the control time can be made almost equal, it is possible to provide a control device with good followability and less rotational fluctuation in controlling a plurality of models.

[Brief explanation of drawings]

The drawings show the structure of an embodiment of the present invention; FIG. 1 is a block diagram, FIG. 2 is a diagram of the principle of rotational speed measurement of the present invention, and FIG. 3 is a detailed diagram. MA, MB, Mc...Modle, I! IA,
h a I Ec...Encoder, Q^, Qs, Q
c...Transistor, DaIvA, DRIvB, D
RIVC...Drive device, DS...Data selector, MPU...Overall control device, CTR, L...City 1j
1 Wholesale section, CNTII... Counter, ALU 1st port 2nd figure 3rd figure

Claims (1)

[Claims] 1. At least two or more DC modes having encoders attached to the mode mode shafts, and the +MIa mode mode motor;
a data selector that selects the encoder signal in the middle;
In a multiple mode control device, which has multiple drive devices, one control device, and one counter for detecting the number of rotations of the modele based on an encoder signal, a plurality of preset DC modes can be used. 1. A DC mode multi-nucleus control device characterized in that encoders are combined so that the outputs i#ea of encoder signals are approximately the same at rotational speeds that are not necessarily the same. 2. In the device described in claim 1, the output of the data selector for selecting the encoder signal is % ml.
A DC mode control device, characterized in that it is configured to serve as an interrupt signal to a JpJ device. 3. In the device described in claim 2, the interrupt signal from the data selector is counted according to the set rotation speed, and the rotation speed count time is set even when the set rotation speed changes. A control device for multiple DC moders, characterized by switching the number of rotations so as to approximate the count time before changing the set rotation speed.