JPS62228703A - Spool valve driving device - Google Patents

Abstract

PURPOSE:To eliminate an output of an excessive motor speed command after recovery of a power supply, by providing the first circuit for detecting a power supply condition, the second circuit for making an output signal to smoothly track a position command signal, and a signal switching device. CONSTITUTION:A driving power supply condition detecting circuit 50 consisting of elements 51, 52, 54, 55, 56 and 57, a control power suply 53, a position command signal tracking circuit 60 consisting of elements 61-64 and a signal switching device 70 are provided. By these, when the motor driving power supply is lost, a motor shaft is fixed and the present value is memorized and also, an excessive motor speed command may not be output after recovery of the power supply even if the position command signal from a host controller is changed while the power supply is being lost, so that the output can track smoothly the position command signal from the host controller.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a spool valve drive device that positions a spool valve using an electric motor such as a pulse motor, and particularly relates to a spool valve drive device that positions a spool valve using an electric motor such as a pulse motor. and N? 1N
Concerning smooth behavior during recovery.

[Conventional technology]

FIG. 3 is a diagram showing the configuration of a conventional example. In Fig. 3, 1 is a position controller, 2 is a servo amplifier, 3 is a servo motor, 4 is a position detector, 5 is a ball screw, 6 is a spool,
7 is a sleeve, 8 is a power supply detector, 9 is a brake, 10 is a brake Ii source, 11 is a buffer amplifier, 12.22 is a comparator, 13.23 is a regulator, 24 is a power control circuit, 2
5 is a speed detection circuit, and 30 is a position detection circuit.

In FIG. 3, position control i11. Essentially 122.23°25, the detector 8 functions regardless of the state of the motor drive power source.

A position command signal Rf from the host controller shown at the left end in the figure is input to the comparator 12 via the buffer 7 amplifier 11 as a command signal er. The current position of the spool 6 is detected by the detector 4, and the detection signal becomes a two-phase pulse signal (FPA, FRB) to the position detection circuit 30 (element 1
4 to 20), and here the position feedback signal e
f and is output to the comparator 12.

The deviation (er-ef) obtained by the comparator 12 is
3 and output as a motor speed command ert+r, which is input to the comparator 22. The two-phase pulse signal (F
PA, FRB) are also input to a speed detection circuit 25, where a motor speed signal em is obtained. This speed signal em
is input to the comparator 22. Therefore, the comparator 22 obtains the deviation (emr-em) from the speed command emr. The regulator 23 calculates a current command ir from the deviation (emr-em) and outputs it to the power control 11 circuit 24.

The motor 3 is driven by the drive 1! supplied from the power control circuit 24! speed controlled by the source. A ball screw 5 connected to the motor shaft drives the spool 6 by converting the rotation of the motor 3 into linear motion.

Live or loss of three-phase power supply is detected by detector 8;
PPA-'1' when live, PPA-'O when lost.
' is output. When PPA='1', the relay 21 in the position controller 1 operates and turns on the contact Xa.Therefore, the brake 9 is energized by the power supply 10, releasing the brake.Also, when PPA='O' , position controller 1
Since the relay 21 returns to its original state and turns off the contact Xa, the brake is applied.

Next, the operation of the position detection circuit 30 will be explained. Discrimination circuit 14
discriminates the phase of two-phase pulse signals (FPA, FRB),
Generate up/down pulses (tJP, DN). Therefore, the up/down counter 15 operates. The value Of of this counter 15 is set by an OR gate 180M extension circuit 19 and an AND gate 2 in order to match the settling timing of the counter value during up-counting or down-counting.
After timing control with 0, register 1
6. AND gate 20 is motor drive 11J
It operates on the condition that the I source is live (PpA-1'). The value Df- of register 16 is D/Δ converter 1
7 into an analog value and supplied to the comparator 12 as a position feedback signal ef.

Motor driven! When the source is lost (PPA-'O'), the output of the AND gate 20 becomes LD-'0',
The output Qf' of the register 16 is held, and
The motor shaft is fixed by the brake 9. 'R? l! After recovery, PPA becomes '1' again, so register 16
The output Qf- follows the counter value Df, the brake 9 is also released, and the motor is in a controlled state.

(Problem to be Solved by the Invention) In the conventional motor drive device described above, when the motor drive power is lost, the motor shaft is fixed and the current value is held, but during this time the position command signal from the host controller is If it has changed, the deviation between the command value and the feedback signal becomes large when 'R[v1 old], so there is a problem that an excessive motor speed command is output and the spool fluctuates excessively.

Therefore, the present invention not only fixes the motor shaft and memorizes the current value when the motor drive power is lost, but also allows the position command signal from the upper controller/roller to change during the power loss. It is an object of the present invention to provide a spool valve driving device that can smoothly track a position command signal from a host controller without outputting an excessive motor speed command after power is restored.

(Means for Solving the Problems) In order to solve the above problems and achieve the object, the present invention takes the following measures.

■ The first circuit for MVi status detection, which has the function of detecting whether the motor drive power supply is live, lost, or restored, holds the position feedback signal when the motor drive power is lost, and makes it follow the position feedback signal when the motor drive power is live. will be established.

■ When the motor drive power supply is live or lost, the output signal follows the position feedback signal, and when the power is restored, the output signal smoothly tracks the position command signal from the upper controller 1-roller. 2 circuits are provided.

■ When the motor drive power supply is live, the position command signal from the host controller is selected, and during loss of the motor drive power supply and after the power is restored, the position feedback signal is selected until the position feedback signal catches up with the position command signal from the host controller. A signal switch is provided for switching signals so as to select the output signal of the second circuit as the position command signal.

[Effect]

By taking such measures, even if the electricity Even if the position command signal from the host controller changes during the power loss, an excessive motor speed command will not be output after the power is restored, and the problem described in (e) above can be solved.

〔Example〕

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention. Note that the same parts as in FIG. 3 are denoted by the same reference numerals, and detailed explanations will be omitted.

The difference between FIG. 1 and FIG. 3 is the contents of the position controller 1. That is, in FIG. 1, elements 51, 52,
Drive 1fm state detection circuit 50 consisting of 54, 55, 56, 57, control power source 53, elements 61, 60, 63, 6
The position command signal tracking circuit 60 consisting of 4, the signal switch 70 and the gate 80 are the characteristic elements of this embodiment. The circuit 50 and gate 80 correspond to the first circuit of the present invention, and the circuit 60 corresponds to the second circuit.

FIG. 2 is a timing waveform diagram showing the operation of this embodiment.

The operation of this embodiment will be explained below. The circuit 50 detects the state of the motor drive power source and outputs the gate 8 in the position detection circuit 30.
A signal G that controls the hold or tracking of 0, a signal TRK that controls the operating state of the tracking circuit 60,
Furthermore, it has a function of outputting a signal PCF to control the signal switching device 70. On the other hand, the tracking circuit 60
When the li source is live or during a power loss (TRK-'O'), the output signal erb is made to follow the position feedback signal ef, and after WIm is recovered, the position [11 order e
It has a II function to track the output signal erb toward era until the deviation between ra and position feedback signal ef becomes small (TRK-'1').

When l Δe l -1era-ef I becomes smaller than a predetermined value and erb sufficiently catches up with era, it is determined that tracking is complete! 62 outputs the completion pulse 〒RKE to the OR gate 55 to reset the flip 70 knob 52, and further outputs the TR
K-'1°→'0', and the circuit 60 is returned to its normal operating state.

The signal switch 70 receives the control signal PC from the circuit 50.
By F, when PCF-'0', er-era, PCF
When = '-1', the position command signal is switched so that it becomes er-erb. PCF-'1' indicates drive power loss and recovery, PCF-'O' indicates live line status.

It should be noted that the present invention is not limited to the embodiments described above, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

〔Effect of the invention〕

According to the present invention, the first aspect described above. Since it has a second circuit and a signal switch, it is possible to fix the motor shaft and store the current value even when the motor drive power is lost, and even when the power is lost, the position from the host controller can be changed. Even if the command signal changes, the host controller I/I can smoothly operate without outputting an excessive motor speed command after the power is restored.
A spool valve driving device that can track a position command signal from a roller can be provided.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of a spool valve driving device according to an embodiment of the present invention, and FIG. 2 is a timing waveform diagram showing the operation of the same embodiment. FIG. 3 is a diagram showing the configuration of a conventional spool valve driving device. 1...Position controller, 2...Servo amplifier, 3...
Servo motor, 4...Position detector, 5...Ball screw, 6...Spool, 7...Sleeve, 8...N
Source detector, 9... Brake, 30... Position detection circuit, 50... Drive am source state detection circuit, 60... Position command signal tracking circuit, 70... Signal switch, 80...・It is a gate.

Claims (1)

[Claims] In a spool valve drive device that uses an electric motor such as a pulse motor to position the spool valve, it detects whether the motor drive power is live, lost, or restored, and when the motor drive power is lost, it holds the position feedback signal and when the motor drive power is live. A first circuit for detecting the power state that has a function of following the position feedback signal, and a circuit that causes the output signal to follow the position feedback signal when the motor driving power is live or lost, and is connected to the upper controller after the power is restored. a second circuit that smoothly tracks the output signal toward the position command signal;
When the motor drive power source is live, the position command signal from the host controller is selected, and during loss of the motor drive power supply and after the power is restored, the second circuit outputs the position command signal until the position feedback signal catches up with the position command signal from the host controller. A spool valve driving device comprising: a signal switcher that switches signals so as to select a signal as a position command signal.