JPS604839A - Detection of unbalance point for rotor and positioning apparatus - Google Patents

Abstract

PURPOSE:To achieve a quick detection of the unbalance position without measuring errors by applying a rotation to detect an unbalance signal which a pulse is generated at each specified angle of rotation obtained by equally dividing one cycle of rotation. CONSTITUTION:An unbalance signal generated with the rotation of a sample W is detected with a sensor 5a (5b) and unwanted frequency components are removed with a filter 11. On the other hand, a reference phase signal generation circuit 12 generates a pulse-like signal synchronizing with an input signal as output of the filter 11. A rotaly encoder 8 measures the rotation of the sample W and generates a pulse signal at each specified angle obtained by equally dividing one cycle. Then, a preset counter 18 receives output and counts outputs of the encoder 8 using output of the circuit 12 as trigger at the constant speed rotation of the sample W and generate an output signal when counts coincide the preset value. Then, a stop device 9 stops the unbalance point of the sample W at the home position by this output signal.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a method for detecting an unbalance point in a rotating body such as an armature, and a device for locating an unbalance point in a rotating body.

(b) Prior art In general, the measurement of the unbalance of a rotating body as described above involves rotating the rotating body under test and measuring the vibrations, centrifugal force, etc. generated due to the unbalance. From the reference phase signal generated in synchronization with the rotation period of the specimen and corresponding to the reference position of the specimen, the magnitude of the unbalance existing in the specimen and the angle of the existing position with respect to the reference position can be calculated using an electrical method. This is done by deriving it by

Conventionally, in this type of measurement, in order to obtain the reference phase signal mentioned above, marks etc. are placed in advance on the outer circumferential surface of the specimen.
During measurement rotation, a detector such as a photocell or a proximity switch scans the outer periphery of the specimen to detect marks, and the detected signal is used as a reference phase signal. According to such conventional methods, not only is it necessary to attach marks, etc. as a reference to the specimen prior to measurement (but also, when detecting marks etc. with a detector, there is no possibility of dirt or scratches on the surface of the specimen). Otherwise, due to variations in diameter or changes in ambient temperature, malfunctions occur constantly, which is a major cause of measurement errors.

(c) Purpose The present invention has been made in view of the above, and provides a method for obtaining a reference phase signal and quickly detecting the position of unbalance, without attaching a reference mark or the like to a specimen, and for determining the position. The purpose of the present invention is to provide a device for positioning.

(D) Configuration The unbalance point detection method of the present invention rotates the specimen and detects the unbalance signal, and also measures the rotation and generates a pulse signal at each predetermined angle that equally divides one circumference of the specimen. Then, a reference phase signal at a predetermined phase of the signal is formed from the detected unbalance signal, and when the specimen rotates at a constant speed, the pulse signal is counted starting from the generation of the reference phase signal, and the counted value is determined in advance. It is characterized in that the position of the specimen relative to a predetermined fixed position at the time when a set predetermined value is reached is detected as an unbalance point.

Further, the unbalance point positioning device of the present invention includes a sensor that detects an unbalance signal generated by the rotation of the specimen, and removes unnecessary frequency components other than signal components having the same period as the rotation period of the specimen from the sensor output. A filter, a reference phase signal generation circuit that uses the filter output as an input signal and generates a pulse-like signal synchronized with the input signal, and a predetermined rotation angle that measures the rotation of the specimen and equally divides one rotation of the specimen. The output of the rotation angle signal generator is input and counted using the rotation angle signal generator that generates a pulse signal for each pulse, and the output of the reference phase signal generator circuit when the specimen rotates at a constant speed is used as a trigger, and the counted value is calculated. a preset counter that generates an output signal when it matches a set preset value;
The present invention is characterized in that it includes a stopping device that stops the specimen when the output signal of the preset counter is generated, and is configured such that the unbalance point of the specimen is stopped at a fixed position.

(e) Examples Examples of the method and apparatus of the present invention will be described below with reference to the drawings.

1 and 2 are a front view and a plan view, respectively, showing essential parts of the mechanical structure of an apparatus according to an embodiment of the present invention.

The specimen W is supported by left and right bearings 1a, lb, and is rotated by a drive belt 3 driven by a drive motor pusher 2. The vibrations generated due to the unbalance of the specimen due to the rotation of the bearings 1a and 1 on the left and right
Spring 4a for each b.

Vibrating knob 5a attached via 4b.

5b. A rotation angle detection roller 6 is disposed on the outer periphery of the specimen W, and is configured to be rotated by contact with the specimen W, and its rotation is transmitted to a rotary encoder 8 via a heald 7. .

Further, at a predetermined position on the outer circumference of the specimen W, for example, directly above the specimen W, a notch 9b is driven into the specimen W by the action of a magnet 9a when a command signal is issued, thereby instantaneously causing the rotation of the specimen W. A stop device 9 is provided which can be stopped.

Next, the circuit configuration of the apparatus according to the embodiment of the present invention described above will be explained based on the block diagram shown in FIG. 3 and the signal waveform diagram of each part during constant speed rotation of the specimen W shown in FIG. 4.

The output of the vibration pickup 5a (or 5b), that is, the unbalance signal A, is input to the filter 11. Filter 1
1 passes a signal component having a period close to the rotational period of the specimen W, but removes other noises, etc. Therefore, its output becomes a substantially sinusoidal signal B synchronized with the rotational period of the specimen W. This substantially sinusoidal signal B is introduced into a reference phase signal generation circuit 12 composed of a shaping circuit 12a and a differentiating circuit 12b. The shaping circuit 12a receives the input substantially sinusoidal signal B.
is shaped into a rectangular wave signal C. At this time, it is desirable to increase the width appropriately at the same time. This rectangular wave signal C is differentiated by the next-stage differentiating circuit 12b and output as a pulsed reference phase signal. As is clear from FIG. 4, this reference phase signal is generated in synchronization with the unbalanced signal A and at the 0'' phase of the unbalanced signal A, and the reference phase signal and the unbalanced signal A are known in the art. It is introduced into an unbalance measuring circuit constituted by a synchronous rectifier circuit, etc., and is used for measuring the magnitude of unbalance, etc. On the other hand, the rotation of the rotation angle detection roller 6 that is in contact with the outer periphery of the specimen W is detected by the belt. The rotary encoder 8 transmitted by the
The outer diameter of the contact part of the rotation angle detection roller 6 of the specimen W, the outer diameter of the pulley of the rotary encoder 8, etc. are set so that, for example, 360 pulses of output pulse signal E are generated per rotation. corresponds to the rotation angle lo of the specimen W.

The timer 13 is turned on at the same time as the drive motor that rotates the specimen W is activated, and the time is slightly longer than the time required for the rotation to reach a constant speed rotation range and for the unbalance measurement circuit to complete measurement of the unbalance. A time t□ is set in advance, and the drive motor is configured to generate an output signal when the time to has elapsed after starting the drive motor. The output F of the timer 13 is the first flip-flop 14.
was introduced as a cent input. The first flip-flop 14 is set to "1" state by the cent input signal.
The output I of the first AND gate 15, whose AND inputs are the output G of , and the above-mentioned reference phase signal R, is introduced as a set input to the second flip-flop 16.

The output I of the second flip-flop 16 is combined with the output pulse signal E of the rotary encoder 8 into a second AND
It is the AND input of the gate 17, and the second AND gate 1
The output J of 7 serves as a count input of a preset counter 18 in which preset data is set. The preset counter 18 counts the human power J input from the second AND gate 17, and when the counted value matches the preset data, it generates an output signal K and activates the stop device 9 to stop the specimen W. It is configured to stop.

Next, the operation of the embodiment of the present invention will be described. FIG. 5 is a signal waveform diagram of each part when the unbalance point of the specimen W is stopped at the position where the stop device 9 is disposed by the apparatus according to the embodiment of the present invention.

After the drive motor is started, the speed of the specimen W is increased to a predetermined constant rotational speed, and the unbalance is measured by the unbalance measuring circuit. When the time to has elapsed after the drive motor was started, the measurement of the unbalance has already been completed, and the specimen W continues to rotate at a constant speed. After the time to has elapsed, the output F of the timer 13 causes the output G of the first flip-flop 14 to become "1". When a reference phase signal is generated in this state, the reference phase signal appears at the output tr of the first AND gate 15. As a result, the output signal (■) of the second flip-flop 1G becomes "1", and from that point on, the output pulse signal E of the rotary encoder 8 appears at the output J of the second AND gate 17, and the recent counter It is counted by 18. That is, when the specimen W rotates at a constant speed, the preset counter 18 starts counting the pulse signals E from the rotary encoder 8 with the generation of the reference phase signal as a starting point.

When the counted value matches the preset recent data, the preset counter 18 generates an output K to activate the stop device 9 and stop the specimen W. The recent data of the preset counter 18 is
In this embodiment, the reference phase signal is generated at the 0° phase of the unbalance signal A, the stop device 9 is disposed at a position of 180° with respect to the vibration pinup 5a, and the rotary encoder Since the output pulse signal E of 8 pieces is generated corresponding to the rotation angle of 1 degree of the specimen W, it is only necessary to make 90 cents. That is, the unbalanced point has a phase difference of 90' with respect to the reference phase signal, and in order to stop the unbalanced point at the location where the stop device 9 is installed, the specimen W must be moved by 90° after the reference phase signal is generated. When rotated, the position where the stop device 9 is disposed coincides with the position of the unbalance point of the specimen W. Note that if there is a time lag in the operation of the stop device 9 with respect to the output signal K of the preset counter 18, this preset data needs to be increased or decreased as appropriate in accordance with that time. In addition, in the method of the present invention, in addition to the example in which the specimen W is stopped at a fixed position as in the above embodiment, a marking device may be provided in place of the stopping device 9 to mark the unbalanced point.

(f) Effects As explained above, according to the present invention, there is no need to attach reference marks or the like to the specimen prior to testing, so one step can be reduced compared to the conventional method. Further, unlike the conventional device, a detector for detecting the reference mark is not required, and there is no detector malfunction, which is the main cause of measurement errors in the conventional device, and the reliability of measurement accuracy is improved. Furthermore, since the test specimen can be stopped instantaneously from the test rotation speed, the test time can be shortened.

Furthermore, a method has already been proposed in which a reference phase signal is obtained by detecting irregularities on the outer periphery of the specimen by scanning the outer periphery of the specimen using a non-marking method. It was impossible to measure if there were no noticeable irregularities. According to the present invention, even if the specimen is a completely smooth object, it can be measured.

[Brief explanation of the drawing]

FIGS. 1 and 2 are a front view and a side view, respectively, of essential parts showing the mechanical structure of an embodiment of the present invention. Fig. 3 is a block diagram showing the circuit configuration of the embodiment of the present invention, Fig. 4 is a signal waveform diagram of the main part when the specimen rotates at a constant speed, and Fig. 5 shows the unbalance point of the specimen according to the embodiment of the present invention. FIG. 4 is a signal waveform diagram of each part when the vehicle is stopped at a fixed position. 3--Drive belt 5a, 5b-Vibration pink-up 6-Rotation angle detection roller 8-Rotary encoder 9-Stop device 11-Filter 12-Reference phase signal generation circuit 13-Timer 14, 16-First ．． Second flip flip 15.
17. -11 1st. Second AND Gate 18 - Preset Counter Patent Applicant Shimadzu Corporation Agent Patent Attorney Nishi 1) New Figure 4 Procedural Amendment 1981 9. ',)3. '21 Mr. B. Commissioner of the Patent Office 1. Indication of the case 1988 Patent Application No. 112369 2. Name of the invention Method for detecting unbalanced point of a rotating body and positioning device 3. Person making the amendment Relationship with the case Patent applicant's address 378 Roots Funatocho, Nijo-shita, Kawaramachi-dori, Nakagyo-ku, Kyoto Name (199) Shimadzu Corporation Representative Setsuo Yokochi 4 Address of agent 15-13 Usagano-cho, Kita-ku, Osaka, f21 M Bookcase 6th stroke: 2. Number of inventions stated in the scope of claims
Add the words ``2'' and 3. Decrease the numbers in the following columns one by one.

Claims (1)

[Claims] (11) Detecting an unbalance signal generated by applying rotation to the specimen, and measuring the rotation to order a pulse signal for each predetermined rotation angle that equally divides one circumference of the specimen, A reference phase signal at a predetermined phase of the signal is formed from the unbalance signal, and the pulse signal is counted starting from the generation of the reference phase signal when the specimen rotates at a constant speed, and the counted value is a predetermined value set in advance. A method for detecting an unbalance point of a rotating body, which is characterized in that the position of the specimen relative to a predetermined fixed position at the time when the rotation is reached is detected as an unbalance point. (2) Detecting an unbalance signal generated by applying rotation to the specimen. A sensor that removes unnecessary frequency components other than signal components with the same period as the rotation period of the specimen from the sensor output, and a filter that takes the output of the filter as an input signal and generates a pulse-like signal that is synchronized with the input signal. a reference phase signal generation circuit that measures the rotation of the specimen and generates a pulse signal for each predetermined rotation angle that divides one rotation of the specimen into equal parts; a preset counter that inputs and counts the rotation angle signal generator output using the output of the reference phase signal generator circuit as a trigger, and generates an output signal when the counted value matches a preset value; and the preset counter. An unbalance point positioning device for a rotating body, comprising a stop device that stops the specimen when an output signal of is generated, and the unbalance point of the specimen is stopped at a fixed position.