JP3016624B2 - Micro index accuracy measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the rotation of a work (hereinafter referred to as "work") in which pitch errors of division marks (hereinafter referred to as "indexes") which are equally arranged in the circumferential direction of a rotating body (hereinafter referred to as "work"). The present invention relates to a micro index accuracy measuring device for detecting inside.

[0002] Such a work includes, in addition to ordinary gears and the like, a pulsar ring for detecting wheel rotation attached to a wheel bearing of an automobile, and the like.

[0003]

2. Description of the Related Art For example, when measuring the accuracy of an index divided at equal intervals on the circumference of a rotating workpiece as in the measurement of a gear, it is necessary to detect a pitch error. As a method therefor, there is known a method of performing static measurement using a pitch gauge or the like. This means that a single pitch error is actually measured, and the adjacent pitch error and the accumulated pitch error are calculated from the recording of the single pitch error over the entire circumference. The single pitch error is the difference between the actual pitch on the pitch circle of adjacent teeth and its correct pitch, and the adjacent pitch error is the difference between two adjacent pitches on the pitch circle, the cumulative pitch. The error is defined as the difference between the sum of the actual pitch on a pitch circle between any two teeth and its correct value (JIS B 1702).

[0004] However, such a static method has a problem that the measurement time is long and the efficiency is low.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to accurately and quickly measure the accuracy of an index provided on the circumference of a rotating work.

[0006]

Means for Solving the Problems A minute index accuracy measuring device of the present invention is a device for detecting a pitch error between an N pole and an S pole alternately magnetized in a circumferential direction of a pulsar ring. A spindle for supporting and rotating the ring, having a rotary encoder for detecting the rotation speed of the spindle and a sensor that detects the magnetic pole of the pulsar ring and generates a corresponding signal, and a high-resolution rotary encoder as the rotary encoder it features a rotary encoder of a low resolution, in the magnetizing operation, to detect the pitch error of the magnetic pole by comparing the rotary et <br/> Nko da or these signals of the sensor and high resolution, magnetized already pulsar When measuring the ring, the signals from the sensor and the low-resolution rotary encoder are compared and the It is obtained to detect the pitch errors.

[0007]

The rotary encoder acts as a master gauge, and by comparing the signal from the sensor with the signal from the rotary encoder, a pitch error of the index of the work can be detected. Therefore, it is possible to measure the fine index accuracy of the work while the work is rotating.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment shown in FIG. 1, an air spindle is constituted by supporting a spindle 1 in a housing 2 in a non-contact manner by a static pressure air bearing. The air spindle is suitable for precision measurement because its rotational torque is very small as compared with that supported by a rolling bearing or the like. A work 9 is attached to the tip of the spindle 1. The other end of the spindle 1 has a rotor 3
Are fixed, and a motor for rotating and driving the spindle 1 is constituted by the stator 4 fixed to the housing 2. In this embodiment, two rotary encoders for detecting the rotation speed of the spindle 1 are mounted. One is a high-resolution rotary encoder 5, which measures the rotational speed of a spindle with a sensor 6 fixed to the housing 2. The other is a low-resolution encoder 7, which measures the rotational speed of a spindle by a sensor (not shown) fixed to the housing 2 in the same manner.

In the case of the pulsar ring illustrated in the figure, the workpiece 9 having division marks or indexes equally distributed in the circumferential direction is magnetized so that the N pole and the S pole are alternately arranged in the circumferential direction.

At the same time that the work 9 is magnetized, the pitch error can be detected and measured. However, in order to accurately magnetize the outer peripheral surface of the work 9, the work 9
It is necessary to keep the number of rotations low. Therefore, the spindle 1 is rotated at a low speed of, for example, 130 rpm or less, and a change in the magnetic pole of the work 9 is picked up by the magnetic sensor 8. On the other hand, the displacement of the high-resolution rotary encoder 5 is picked up by the sensor 6 as a master gauge, and the signals from the sensors 8 and 6 are read and compared as shown in FIG. Can be detected.

It is not necessary to measure the pitch error of the magnetized work 9 at a low speed. In fact, in the case of pulsaring, it is necessary to check the accuracy at an actual vehicle traveling speed of 2,000 to 3,000 rpm. However, when the spindle 1 is rotated at a high speed of, for example, about 130 rpm or more and about 10,000 rpm,
The number of division lines of the rotary encoder increases, and its signal measurement is impossible (no amplifier). Therefore, the pitch error is detected and measured by comparison with the divided signal waveform of the low-resolution rotary encoder 7. In this case, the cumulative pitch error can also be measured.

The present invention measures the accuracy of magnetic division (low-speed rotation) in the magnetizing operation of a pulsar ring attached to a wheel bearing or the like of an automobile in an anti-lock brake system of an automobile, and a measurement at an actual automobile speed. (High-speed rotation) is possible. Further, the present invention can be applied to a spindle mounted on a wheel bearing for measuring an anti-skid signal.

[0013]

As described above, the present invention is an apparatus for detecting a pitch error between an N-pole and an S-pole alternately magnetized in the circumferential direction of a pulsar ring. A rotary encoder having a high-resolution rotary encoder and a low-resolution rotary encoder having a spindle for rotating, a sensor for detecting a magnetic pole of the pulsar ring and generating a corresponding signal, and a rotary encoder for detecting a rotation speed of the spindle; it features a, in the magnetizing operation, the sensors and comparing the high-resolution rotary encoder or these signals to detect the pitch error of the pole, in the measurement of magnetization already pulsar ring, wherein the sensor and the low Detected pitch error of magnetic pole by comparing signals from rotary encoder with high resolution Therefore, the pitch error of the magnetic poles alternately magnetized in the circumferential direction of the pulsar ring can be measured during rotation. Specifically, the pitch error can be detected and measured at the same time when the magnetizing operation is performed. Therefore, the measurement time is significantly reduced, and highly accurate measurement is possible.

In addition, by providing a high-resolution rotary encoder and a low-resolution rotary encoder in parallel, the pitch accuracy of a high-precision gear or other work can be reduced from a low speed (up to 130 rpm) to a high speed (up to 130 rpm) with one device. 10,000rpm)
It can measure up to high accuracy.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment.

FIG. 2 is a signal waveform diagram.

[Explanation of symbols]

 Reference Signs List 1 spindle 2 housing 3 rotor 4 stator 5 rotary encoder (high resolution) 6 sensor 7 rotary encoder (low resolution) 8 magnetic sensor 9 work

Claims (1)

(57) [Claims] An apparatus for detecting a pitch error between an N pole and an S pole alternately magnetized in a circumferential direction of a pulsar ring, comprising: a spindle for supporting and rotating the pulsar ring; It has a sensor that detects the magnetic poles and generates a corresponding signal and a rotary encoder that detects the rotation speed of the spindle, and a high-resolution rotary encoder and a low-resolution rotary encoder are provided as the rotary encoder. rotary encoder of the sensor and high resolution
Detecting a pitch error of the magnetic pole by comparing the pressure these signals, in the measurement of the magnetization already pulsar ring, detecting the pitch error of the magnetic pole by comparing a signal from the rotary encoder of the sensor and the low-resolution A micro index accuracy measuring device characterized by the following.