JPH0336976A - Finite rotation motor - Google Patents

Abstract

PURPOSE:To control a minute angle at high speed and with a high accuracy by detecting a direct-acting operation through a position sensor after converting a motor rotation angle into the direct-acting operation through pinion and rack, by obtaining a deviation between a temperature-compensated sensor signal and position command signal and a speed command signal deviation, and by feedback-controlling these deviations so that they are reduced to zero. CONSTITUTION:In a moving coil type motor 1 using a high flux density magnet, the rotation angle of the motor is converted into DC voltage by a DC tachometer generator 3 and into the direct-acting operation of a magnetic plate 7 via pinion and rack 4, 5 and further converted into a signal by a non-contact sensor 8. Then, a position sensor signal Vpf passed through a temperature compensator 10 and a position command signal Vpo from a commander part 9 are compared by a first comparator 11 so that a position deviation signal Vp is outputted and inputted to PID controller to output a speed command signal Vs. In a second comparator 13, the speed command signal Vs and a feedback signal Vsf from the tachometer generator are compared with each other and a speed deviation signal Vs is outputted and inputted to a power amplifier 14 to output a motor control signal Vout.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a finite co-rotating motor used as a drive source for a scanning drive device in a laser processing machine such as a laser trimmer or a laser marker, or in OA equipment.

[Conventional technology]

The conventional limited rotation electric motor mentioned above is Patent No. 116433.
0 and Utility Model Application Publication No. 50-76315 are known.

Among the above conventional systems, the former has a capacitance type rotation angle sensor with low inertia and high resolution attached to the rotation axis of the rotor, and this rotation angle sensor detects the rotation angle of the rotor. is detected, and the rotation angle of the rotor is controlled based on this detected value.

In the latter case, the rotor rotation angle is detected by a potentiometer.

[Problem to be solved by the invention]

Among the above conventional technologies, the former uses a rotation angle sensor with low inertia and high resolution, so it is capable of high-speed response, but due to temperature drift of the rotation angle sensor, the response is only possible for a short period of time. There is a problem that accuracy cannot be maintained.

In addition, the latter type has a low inertia due to its structure.
, and since a potentiometer is used to detect the angle,
The problem is that high accuracy cannot be expected.

The present invention has been made in consideration of the above, and aims to provide a finite rotating electric motor that can control minute angles at high speed and with high precision, and that can develop high precision position repeatability over a long period of time. be.

[Means to solve the problem]

In order to achieve the above object, the finite rotation electric motor according to the present invention has a pinion gear fixed to the rotating shaft of a moving coil type motor using a high magnetic flux density magnet, and a magnetic plate fixed to one end of a rack gear that meshes with the pinion gear. A non-contact type position sensor is installed at a position facing this magnetic plate, a temperature compensation circuit is interposed in the output circuit of this position sensor, and the output circuit of this position sensor and the command part of the first comparator are connected. PI is connected to the input terminal, and the PI is connected to the output side of this first comparator.
D control section is inserted, and the output circuit of the first comparator and the output circuit of the tacho generator attached to the rotating shaft of the motor are connected to the input terminal of the second comparator, and the second comparator is connected to the input terminal of the second comparator. The configuration is connected to a power amplifier for the motor.

[For production]

The rotation angle of the motor is converted into direct motion by a pinion gear and a rack gear, and the movement of this is detected by a position sensor. The detected value of this position sensor is electrically compensated for its temperature drift in a temperature compensation circuit, and then compared with a command signal from a command section in a first comparator. The deviation output from the first comparator is subjected to PID processing in the PID control section and output as a speed command, and this speed/command and the feedback signal from the tachogenerator are compared in the second comparator to calculate the speed deviation. Output to power amplifier.

〔Example〕

Embodiments of the present invention will be described based on the drawings.

Figure Φ1 is a moving coil type motor using a high magnetic flux density magnet, which is supported by a housing 2 and is configured to reciprocate and rotate over a predetermined finite rotation angle, for example, 10 degrees, using a direct current. There is. 3 is a p attached to one end of the rotating shaft of this moving coil type motor 1.
The rotation angle of the moving coil motor 1 is detected by applying a DC voltage. In addition, the moving coil type motor 1
A pinion gear 4 is fixed to the other end of the rotating shaft.

5 is a rack gear that meshes with this pinion gear 4;
This rack gear 5 is slidably supported by the nozzle housing 2 via a guide bearing 6, and a magnetic plate 7 is attached to one end of this rack gear 5. Reference numeral 8 denotes a non-contact type position sensor that is provided facing away from the magnetic plate 7 in the moving direction.By detecting the position of the magnetic plate 7 with this position sensor 8, the rotation angle of the moving coil type motor 1 can be determined. It is designed to be detected. The rack gear 5 is urged in a direction away from the position sensor 8 by a spring 5a.

9 is a command unit that outputs a position command Vpo for the rotation angle of the moving coil motor 1; 10 is a sensor temperature compensation circuit interposed in the output circuit of the position sensor 8;
The sensor output signal vpr is outputted by electrically compensating for the temperature drift of the output signal. 11 is a first comparison field that compares the position command Vpo and the sensor output signal Vpr; 12 is a PID that performs a PID calculation on the deviation signal ΔVp from the first comparator 11;
The ID control section 13 is a second comparator that compares the speed command Vs from the PID control section 12 and the feedback signal Vsr from the tacho generator 3, and the second comparator 14 receives the speed deviation ΔVs from the second comparator 13. This is a motor power amplifier that outputs a control signal Vout to the moving coil motor 1.

The operation of controlling the rotation angle of the moving coil motor 1 by the control circuit will be explained based on the flowchart shown in FIG.

Step 1 A command signal Vpo for the position (rotation angle) of the moving coil motor 1 is output from the command unit 9.

Step 2 The command signal Vpo from the command unit 9 and the detection signal Vp(' detected by the position sensor 8 and compensated by the sensor temperature compensation circuit 10 are compared in the first comparator 11, and the If the difference is zero, the command value and the actual value are the same, so positioning is completed.If the comparison value is not zero, the process goes to step 3.

Step 3 The first comparator 11 outputs the deviation ΔVp.

Step 4: The PID control unit 12 performs PID calculation processing on the deviation signal ΔVp, and outputs the result as a speed command Vs.
At this time, Vs-K is 1Δvp, and K is PID
It is a gain.

Step 5 The speed command Vs from the PID control unit 12 and the feedback signal Vsr from the tacho generator 3 are compared (Vs-Vsr) by the second comparator 13 to determine the speed, and if the difference is zero. The commanded speed is completed. Then, if the difference is not zero in the speed determination described above, the process goes to step 6.

Step 6 The second comparator 13 outputs the speed deviation ΔVs, which is ΔVsmKI Vp-Vsl'.

Step 7 Based on the speed 7 and the deviation ΔVs from the second comparator 13, the output Vout is output from the power amplifier 14. At this time, vout- is 2ΔVs, and K2 is the motor speed gain.

Step 8 The rotation of the moving coil motor 1 is converted into direct operation by the position sensor 8 based on the relationship between the pinion gear 4 and the rack gear 5. At this time, Rθ-X is the radius of the pinion gear 4,
X is the moving distance of the rack gear 5.

Step 9 Position signal ■p corresponding to the above Rθ−X from the position sensor 8
When r is output to the first comparator 11 and the process goes to step 2, Vp "-K 3 RN', K3 is the correction gain (':z).

Furthermore, in step 5, the output signal V in step 7 is
The rotation result of the moving coil motor 1 driven by OUT is manually inputted as the output Vsr from the tacho generator 3.

〔Effect of the invention〕

According to the present invention, minute angles can be controlled at high speed and with high precision;
Also, it can demonstrate high precision position repeatability over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a flow chart. 1 is a moving coil type motor, 3 is a tacho generator, 4 is a pinion gear, 5 is a rack gear, 7 is a magnetic plate, 8 is a position sensor, 9 is a command unit, 10 is a sensor temperature compensation circuit, 11.13 is a comparator, 12 is the PID control unit, 1
4 is a power amplifier for the motor.

Claims (1)

[Claims] A pinion gear is fixed to the rotating shaft of a moving coil type motor that uses high magnetic flux density magnets, a magnetic plate is fixed to one end of a rack gear that meshes with the pinion gear, and a non-contact position sensor is installed at a position opposite to this magnetic plate. A temperature compensation circuit is interposed in the output circuit of this position sensor, the output circuit of this position sensor and the command section are connected to the input side of the first comparator, and a PID control circuit is connected to the output side of the first comparator. A second comparator is inserted between the output circuit of the first comparator and the output circuit of the tachogenerator attached to the rotating shaft of the motor.
A finite rotation electric motor, characterized in that the second comparator is connected to the input side of a comparator, and the second comparator is connected to a power amplifier for the motor.