SU1434307A1 - Method of monitoring the bearings of an electric motor - Google Patents

Abstract

The invention relates to the field of mechanical engineering and can be used to control ball bearings. The goal is to demonstrate the accuracy of control of ball bearings. The measurement of the resonant frequency is performed in the radial direction continuously while the rotor rotates relative to the stator. A spectral analysis of the resonance frequency variation is performed. The second harmonic of the variation of the resonant frequency is selected relative to the frequency of rotation of the rotor. The magnitude of the amplitude of the second harmonic determines the amount of skew of the rotor ring of the ball bearing, and the phase - the direction of skew. By estimating skew, control accuracy is improved. 1 il. i O)

Description

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The invention relates to mechanical engineering and can be used to control ball bearings.

The aim of the invention is to improve the accuracy of control of the ball bearings in the assembled electric motor.

The drawing shows the functional diagram of the device for the implementation of the proposed method

The device contains a shaker 1, which includes a vibration sensor 2 and a vibrator 3. On the shaker table, there is a mandrel 4 for securing the tested motor in it. The mandrel 4 is connected by a belt drive 5 with an electric motor 6. The vibrator 3 input and the vibration sensor 2 output are connected to a dynamic parameter meter 7 (PID) 7, The PID 7 information output is connected to a recorder 8, the Photo sensor 9 is connected and the PID 7,

The device works as follows.

The motor under test is mounted in the mandrel 4 on the vertical stand 1 so that radial aibration acts on the motor bearings. The rotor of the motor under test is connected to the belt transmission 5. A signal is sent to the vibrator 3 of the vibrostand 1 from the device IDP 7, the Vibrator 3 sets the motor under test to radial harmonics

rotor bearings. This leads to the fact that a variation of the resonance frequency f occurs. IDP 7 registers the variation of the resonant frequency and generates a signal to the recorder 8, which builds the dependence of f on the angle of rotation q of the rotor relative to the stator. The magnitude of the amplitude of the second harmonic determines the amount of skew of the rotary rings of the ball bearings, and the phase of the skew direction. The magnitude and direction of skewing are determined from calibration charts,

In order to install the stator rings of the ball bearings of the motor under test, the rotor of the electric motor is fixedly mounted on the vibration stand 1. During the test, rotate the stator relative to the rotor. The taken characteristics of the variation of the resonant frequency are similar to those given,

The presence of perekos in ball bearings is the cause of uneven wear, asymmetry of reactions to external disturbances, which is especially

unacceptable in precision electric motors - gyromotors.

The invention makes it possible to drastically improve the control accuracy by estimating the second harmonic misalignment of the variation of the resonant frequency when the rotor of the motor rotates.

hesitation. Vibration of test subject

the motor is sensed by the vibration sensor 2 and transmitted to the IDP 7, which automatically adjusts the frequency of the vibrator 3 to the resonant frequency of the motor under test. When electric motor 6 is turned on, the rotor of the motor being tested is driven by a belt drive 5. When the motor rotates the motor being tested, the mark modulates the reflected light flux, which is perceived by the photosensor 9, the signal from the latter is amplified by the PID 7 and fed to the recorder 8, which gives a graph angular velocity of rotation of the rotor.

If the rotor rings of the ball bearing of the motor under test are installed with a skew, then an imbalance arises during vibration

Form la invention

The method of controlling the ball bearings of an electric motor, namely, that the motor is mounted on a shaker, continuously vibrates when the rotor rotates relative to the stator, the level of the vibrator is measured, the frequency and the resonant frequency, which is measured by: spectral analysis of the variation of the radial resonant frequency, isolate the second harmonic of the variation of the resonant frequency relative to the frequency of rotation of the rotor. and the magnitude of the amplitude of the second harmonic dissolved limit value skew rotor rings of ball bearings, and in phase - the direction of the skew.

Claims (1)

Claim A method of controlling ball bearings of an electric motor, which consists in installing the electric motor on a vibrating stand, continuously exciting vibration when the rotor rotates relative to the stator, measuring the vibration level, twisting and registering the resonant frequency, characterized in that, in order to increase the control accuracy, a spectral analysis of the radial variation is carried out resonant frequency, emit the second harmonic of the variation of the resonant frequency relative to the rotor speed. and the magnitude of the amplitude of the second harmonic is determined divide the skew value of the rotor rings of ball bearings, and the phase - the skew direction.