JP2013003053A - Device for correcting encoder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for correcting an encoder capable of improving productivity and suppressing occurrence of human errors during mounting of a motor and deterioration of correction accuracy due to the deterioration of concentricity between encoders.SOLUTION: A device for correcting an encoder corrects an encoder under test 1 which performs position detection for a motor under test 2. The device includes: a reference encoder 4; coupling parts 5 and 7 which are mounted on the reference encoder and by which a motor shaft 6 of the motor under test and the central axis of the reference encoder are coupled with each other; and a support part 3 by which the reference encoder is freely movably supported along a surface perpendicular to the central axis of the reference encoder.

Description

  The present invention relates to an encoder correction apparatus.

  As a method for correcting the encoder under test by driving the motor under test, a reference encoder with higher accuracy than the encoder under test and the motor under test are installed on a horizontal base and connected concentrically via manual coupling. There is a method of providing correction data by simultaneously sampling encoder position data.

  Providing correction data with a high-precision encoder reduces post-detection errors due to irregularities in parts processing accuracy and assembly errors. As the correction method, the A and B phase pulses output from the encoder under test and the reference encoder are converted into position data by separate counters, synchronized using a calculation circuit, and stored in the storage area. Correction information is generated and provided to the encoder under test via an arithmetic circuit.

JP-A-4-194615

  As the accuracy of the encoder advances, the demand for improving the accuracy of the correction device also increases. In the above H / W structure according to the prior art, a manual coupling is used to connect the reference encoder to the motor under test, and since both the encoders of the reference encoder and the encoder under test are mounted horizontally, the motor Human errors are likely to occur during installation, and there was a problem of correction accuracy deterioration due to deterioration of concentricity between both encoders. There is also a problem that productivity is not improved due to manual attachment.

  The present invention has been made in view of the above, and an encoder correction device capable of suppressing human error at the time of motor attachment and deterioration of correction accuracy due to deterioration of concentricity between encoders and improving productivity. The purpose is to obtain.

  In order to solve the above-described problems and achieve the object, the present invention is an encoder correction device that corrects an encoder under test for detecting the position of a motor under test, and is attached to the reference encoder and the reference encoder. A connecting portion that connects the motor shaft of the motor under test and the central axis of the reference encoder, and a support portion that supports the reference encoder so as to be freely movable along a plane perpendicular to the central axis of the reference encoder. Features.

  According to the present invention, since the reference encoder is supported so as to be freely movable along a plane perpendicular to the center axis of the reference encoder, when connecting the motor shaft of the motor under test and the center axis of the reference encoder, Is automatically aligned. As a result, the accuracy of concentricity can be improved by combining the encoder under test and the reference encoder, and human error during motor installation and deterioration of correction accuracy due to deterioration of concentricity between encoders can be suppressed, and productivity can be improved. Can be achieved.

FIG. 1 is a block diagram showing a schematic configuration of an encoder correction apparatus according to Embodiment 1 of the present invention. FIG. 2 is a side view showing a schematic configuration of the encoder correction apparatus according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view taken along the line AA shown in FIG. 2 and is a diagram illustrating a schematic configuration of a chuck portion of the motor shaft. FIG. 4 is a block diagram illustrating a schematic configuration of an encoder correction apparatus according to a modification of the first embodiment. FIG. 5 is a block diagram showing a schematic configuration of the encoder correction apparatus according to the second embodiment of the present invention. FIG. 6 is a side view showing a schematic configuration of the encoder correction apparatus according to the second embodiment of the present invention.

  Hereinafter, an encoder correction apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a schematic configuration of an encoder correction apparatus according to Embodiment 1 of the present invention. The encoder correction apparatus combines the encoder under test 1 and an encoder with higher accuracy than the encoder under test 1 (hereinafter: reference encoder 4), simultaneously samples the position data of both, measures the error of the position data, and corrects the correction value. Create

  As shown in FIG. 1, the motor under test 2 is driven using a driving device 9 in a state where the motor under test 2 and a reference encoder 4 having a signal processing unit built therein are connected. At that time, the signal processing circuit 10 samples the position data (counter value) of the encoder under test 1 having a signal processing unit therein and the position data (counter value) of the reference encoder 4 in synchronization.

  The signal processing circuit 10 has a function of acquiring data by serial communication and buffering it in the SRAM area 10a in the apparatus, and has a function of sending the buffered data to the PC 11 (the sampling interval can be changed). The PC 11 performs arithmetic processing based on the obtained data, and corrects the encoder under test 1 via the signal processing circuit 10.

  FIG. 2 is a side view showing a schematic configuration of the encoder correction apparatus according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view taken along the line AA shown in FIG. 2 and is a diagram illustrating a schematic configuration of a chuck portion of the motor shaft.

  As for the H / W structure, as shown in FIGS. 2 and 3, the motor under test 2 is installed on the aluminum plate 8, the motor under test 2 and the reference encoder 4 are used, and the air cylinder 5 and the three-claw chuck 7 are used. Coupling with. The three-claw chuck 7 surrounds and holds the motor shaft 6 of the motor under test 2 and the central axis of the reference encoder 4 from the periphery. In this way, the air cylinder 5 and the three-claw chuck 7 constitute a connecting portion that connects the motor shaft 6 of the motor under test 2 and the central axis of the reference encoder 4. The connecting portion is attached to the reference encoder 4.

  In this structure, since the position data of the encoder 1 to be tested and the reference encoder 4 are simultaneously sampled by driving the motor 2 to be tested, the reference side motor is not required, and as a result, between the encoder under test 1 and the reference encoder 4 Can be reduced, and mechanical errors due to tilt can be reduced.

  The coupling between the motor under test 2 and the reference encoder 4 is automatically performed by turning on and off the air. The reference encoder 4 is floated without being fixed, and the XY linear guide (support portion) 3 supports the connecting portion such as the three-jaw chuck 7 so that the reference encoder 4 is centered through the connecting portion. It is supported so as to be freely movable along a plane perpendicular to the axis.

  Thus, if the motor shaft 6 of the motor under test 2 and the center axis of the reference encoder 4 are coupled by the three-jaw chuck 7, the reference encoder 4 moves so that the center axis is concentric with the motor shaft 6. The motor shaft 6 and the center axis of the reference encoder 4 are automatically aligned. With this structure, it is possible to improve the accuracy of concentricity between the encoder under test 1 and the reference encoder 4, reduce human errors by omitting the coupling part replacement work, and improve productivity.

  Also, since the encoder correction device is not provided with a reference side drive motor, and only the reference encoder 4 performs simultaneous sampling by driving the motor under test 2, the mechanical error due to the drive motor can be eliminated, or the encoder under test 1 It is possible to reduce the error due to the inclination between the reference encoder 4 and the correction accuracy.

  FIG. 4 is a block diagram illustrating a schematic configuration of an encoder correction apparatus according to a modification of the first embodiment. In the first embodiment, since each encoder 1 and 4 has a built-in signal processing unit, it is assumed that the A and B phase pulses are processed by itself and position data (counter value) is output to the outside. It has become.

  In this modification, the encoders 1 and 4 that output A and B phase pulses are used. More specifically, the A and B phase pulses respectively output from the encoder under test 1 and the reference encoder 4 are converted into position data (counter value) using the counter 13 and taken into the signal processing circuit 10 by serial communication. . Other correction procedures and H / W structure are the same as those in the first embodiment.

Embodiment 2. FIG.
FIG. 5 is a block diagram showing a schematic configuration of the encoder correction apparatus according to the second embodiment of the present invention. FIG. 6 is a side view showing a schematic configuration of the encoder correction apparatus according to the second embodiment of the present invention.

  In the first embodiment, the signal processing circuit 10 samples the position data (counter value) of the encoder under test 1 in synchronization with the position data acquired by the driving device 9. On the other hand, in the second embodiment, as shown in FIG. 5, it is possible to use the drive encoder 12 and separate the reference encoder 4 from the drive device 9.

  In this case, since the position data (counter value) of the encoder under test 1 and the reference encoder 4 can be synchronized and sampled by the signal processing circuit 10, it is affected by the synchronization of capture between the drive encoder 12 and the drive device 9. Therefore, it becomes easy to vary the sampling period. Further, if the sampling period of the signal processing circuit 10 is improved, the processing speed can be improved.

  As for the H / W structure, as shown in FIG. 6, the reference encoder 4 is attached between the air cylinder 5 and the drive encoder 12. Other structures are the same as those of the first embodiment shown in FIG.

  As described above, the encoder correction apparatus according to the present invention is useful for correcting an encoder used in a motor.

1 Encoder under test 2 Motor under test 3 XY linear guide (support)
4 Reference encoder 5 Air cylinder (connecting part)
6 Motor shaft 7 Three-jaw chuck (connecting part)
8 Aluminum plate 9 Drive device 10 Signal processing circuit 10a SRAM area 12 Drive encoder 13 Counter

Claims (6)

An encoder correction device for correcting an encoder under test for detecting a position of a motor under test,
A reference encoder;
A connecting portion attached to the reference encoder for connecting a motor shaft of the motor under test and a central axis of the reference encoder;
An encoder correction apparatus comprising: a support portion that supports the reference encoder so as to be freely movable along a plane perpendicular to the central axis of the reference encoder.   The encoder correction apparatus according to claim 1, wherein the support portion is an XY linear guide.   The encoder correction apparatus according to claim 2, wherein the XY linear guide supports the connecting portion.   The encoder correction apparatus according to any one of claims 1 to 3, wherein the connecting portion is a chuck that surrounds and holds a motor shaft of the motor under test and a central axis of the reference encoder from the periphery. .   The encoder correction apparatus according to claim 1, further comprising a counter that converts the A and B phase pulses output from the reference encoder into a counter value. A driving device for driving the motor under test;
The encoder correction device according to claim 1, further comprising a drive encoder attached to the reference encoder and outputting position data to the drive device.

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