Ovality measuring instrument for slip ring of alternating current motor or commutator of direct current motor

Abstract

The utility model discloses an ovality measuring instrument for a slip ring of an alternating current motor or a commutator of a direct current motor, which comprises a linear displacement sensor, a probe, an analog data processor and a display instrument, the signal output end of the linear displacement sensor is connected with the signal input end of the analog data processor, and the analog data processor converts voltage signals output by the linear displacement sensor into length data and transmits the length data to the display instrument. The measuring instrument overcomes the defects of traditional ovality measurement, can be used when the motor is disassembled or not disassembled, is small in size and convenient to carry, timely displays and stores measured data on site, and improves the efficiency of ovality measurement operation.

Description

TECHNICAL FIELD

[0001] The utility model relates to motor detection technical field especially relates to a kind of ovality measuring instrument for alternating current motor slip ring or direct current motor commutator. BACKGROUND

[0002] The slip ring and carbon brush of the alternating current three-phase asynchronous winding motor are important components of dynamic and static contact and energy conversion. The slip ring can be oval due to various reasons such as the quality of carbon brush, spring pressure, load condition and magnetic field change. The harm caused by the ovality of the motor slip ring includes: 1. Individual carbon brush vibrates severely on the slip ring, and obvious jumping can be seen during operation, which can easily cause the carbon brush or brush braid to vibrate and break; 2. The slip ring generates severe heat, and the current passing through the remaining carbon brushes increases due to the vibration and breakage of individual carbon brushes, which causes the temperature of the slip ring to rise, and even the slip ring changes color due to heat; 3. The temperature rise of the carbon brush and the slip ring causes the output power of the motor to decrease compared to the rated output power.

[0003] The excitation current of the alternating current three-phase synchronous motor is generally introduced through the slip ring and carbon brush. Therefore, the wear of the working surface between the slip ring and the carbon brush includes two types: 1. Pure mechanical wear; 2. Electrical wear and mechanical wear under the action of current. Both types of wear can cause the slip ring to be oval. The harm caused by the ovality of the motor slip ring is the same as described above.

[0004] During the operation of the direct current motor, sparks are easily generated between the brush and the commutator, which can cause harm to the operation of the motor. When the level of the sparks is too high, the motor and the operating equipment can even be burned out. The generation of sparks is caused by various reasons, and the mechanical aspect is an important reason. The proportion of the commutator eccentricity and the protrusion of the commutator surface segment or mica segment is also relatively large.

[0005] Therefore, it is necessary to regularly measure the ovality of the slip ring and the commutator to ensure that it is within the standard.

[0006] Currently, the method for measuring the ovality of the slip ring and the commutator is to adsorb the dial indicator seat on the fixed component, hit the dial indicator head on the surface of the measured slip ring or commutator, and rotate the motor rotor to measure. This measurement method has a large measurement error through manual monitoring and recording on site, and the measurement data cannot be stored, which reduces the efficiency of the measurement operation. SUMMARY

[0007] The utility model solves the technical problem to provide a kind of ovality measuring instrument for alternating current motor slip ring or direct current motor commutator, and the measurement instrument overcomes the defects of traditional ovality measurement, and can be used in motor disassembly or not disassembly, and the volume is small, portable, measurement data is displayed and stored in time on site, and the efficiency of ovality measurement operation is improved.

[0008] The utility model discloses an ovality measuring instrument for AC motor slip ring or DC motor commutator, which comprises a linear displacement sensor, a probe, an analog data processor and a display instrument.

[0009] Further, the probe is a roller or a roller pin.

[0010] Further, the linear displacement sensor comprises a shell, a variable resistance slide rail and a sliding block, the variable resistance slide rail is arranged in the shell, the sliding block is arranged on the variable resistance slide rail and moves along the variable resistance slide rail, the sliding block extends from the end face of the shell and is provided with a connecting rod, and the probe is arranged on the end face of the connecting rod.

[0011] Further, the measuring instrument further comprises a clamping head, the clamping head is arranged on the end face of the connecting rod, and the probe is clamped by the clamping head.

[0012] Further, the display instrument is provided with a storage chip and a USB interface, the storage chip stores measurement data, and the USB interface is connected with an external data storage device to realize export of the measurement data.

[0013] Since the ovality measuring instrument for AC motor slip ring or DC motor commutator adopts the above technical scheme, the measuring instrument comprises the linear displacement sensor, the probe, the analog data processor and the display instrument, the probe is arranged on the measuring end of the linear displacement sensor, the signal output end of the linear displacement sensor is connected with the signal input end of the analog data processor, and the analog data processor converts the voltage signal output by the linear displacement sensor into length data and then transmits the length data to the display instrument. The measuring instrument overcomes the defects of the traditional ovality measurement, can be used when the motor is disassembled or not disassembled, has small volume and is convenient to carry, measurement data can be displayed and stored in real time on site, and the efficiency of the ovality measurement operation is improved. BRIEF DESCRIPTION OF DRAWINGS

[0014] The utility model will be further explained in detail in combination with the drawings and embodiments:

[0015] Figure 1 It is the structure schematic diagram of this ovality measuring instrument;

[0016] Figure 2 It is the roller probe schematic diagram in this measuring instrument;

[0017] Figure 3 It is the roller pin probe schematic diagram in this measuring instrument. DETAILED DESCRIPTION

[0018] The application is used for measuring the ovality of the commutator of an AC motor or a DC motor. Figure 1 As shown in the drawings, the ovality measuring instrument for the commutator of an AC motor or a DC motor comprises a linear displacement sensor 1, a probe 2, an analog data processor 3 and a display instrument 4, the probe 2 is arranged at the measuring end of the linear displacement sensor 1, the signal output end of the linear displacement sensor 1 is connected to the signal input end of the analog data processor 3, and the analog data processor 3 converts the voltage signal output by the linear displacement sensor 1 into length data and then transmits the length data to the display instrument 4.

[0019] Preferably, as shown in the drawings, the probe 2 is a roller 21 or a roller pin 22. Figure 2 Figure 3 Preferably, as shown in the drawings, the probe 2 is a roller 21 or a roller pin 22.

[0020] Preferably, as shown in the drawings, the linear displacement sensor 1 comprises a shell 11, a variable resistance slide rail 12 and a sliding block 13, the variable resistance slide rail 12 is arranged in the shell 11, the sliding block 13 is arranged on the variable resistance slide rail 12 and moves along the variable resistance slide rail 12, the sliding block 13 extends out of the end face of the shell 11 and is provided with a connecting rod 14, and the probe 2 is arranged at the end face of the connecting rod 14. Figure 1 Preferably, the measuring instrument further comprises a clamping head 5, the clamping head 5 is arranged at the end face of the connecting rod 14, and the probe 2 is clamped by the clamping head 5.

[0021] Preferably, the display instrument 4 is provided with a storage chip 41 and a USB interface 42, the storage chip 41 stores the measurement data, and the USB interface 42 is connected to an external data storage device to realize the export of the measurement data.

[0022] The measuring instrument is small in size, convenient to carry and easy to operate on site, the measurement data can be displayed in real time on site and can also be stored, the output type chart or value can be freely selected, and the installation mode can be adsorbed on the fixed components such as the end cover of the motor or fixed on the brush box.

[0023] During the measurement operation, the probe is installed in contact with the surface of the commutator (slip ring) of the measured motor, and the motor rotor is slowly rotated. Since the commutator (slip ring) of the motor has an oval shape, the running track of the probe is not a straight line but a fluctuating motion curve. Therefore, the displacement of the sliding block on the variable resistance slide rail is different, the variable resistance slide rail is connected to a stable DC voltage and allows a small current to pass through, the voltage between the sliding block and the starting end of the variable resistance slide rail is proportional to the length of the sliding block, different voltage values are converted into length values by the analog data processor and continuously and real-timely displayed on the display instrument, the refresh rate of the display instrument is ≥300 ms / time, the rotation is stopped to complete a measurement, and the measurement data can be stored locally or externally.

[0024] ​​

[0025] The present measuring instrument generally adopts needle probe measurement for the slip ring ellipticity of non-spiral line, and adopts roller measurement for the slip ring or commutator with spiral line; the linear displacement sensor can be adsorbed on the rigid part of the motor by using a magnetic base, or fixed on the brush holder or brush rod by using a special clamp; the measurement data can be transmitted to the display instrument by using a shielded cable, and the display instrument is placed at a convenient observation position, or directly connected to a notebook computer. After the installation of the measuring instrument is completed, it is checked whether the fixation is firm, whether the probe contact is good, and whether the display instrument display is normal, and the display instrument panel display can also be directly zeroed. Then, the motor rotor is slowly rotated, and the rotation speed should be less than 5 RPM, and the starting position is marked before rotation. The measurement data can be directly observed and stored by the display instrument. If re-measurement is required, multiple measurements can be performed. It should be particularly noted that the commutator with long axial length should be measured at two to three points, and the slip ring should be measured phase by phase; if the display instrument is used for monitoring, the slip ring or commutator can be marked at the position with the largest data change, and if a notebook computer is used for monitoring, the elliptical position of the slip ring or commutator can be directly marked on the screen by software.

[0026] The present measuring instrument can solve the defects that the measurement data obtained by using a dial gauge can only be manually monitored and recorded on site, and cannot be stored, and can achieve real-time data storage, on-site and remote monitoring of measurement data, and image processing of data, so that the ellipticity of the slip ring or commutator can be directly and intuitively displayed.

Claims

1. An ovality measuring instrument for an AC machine slip ring or a DC machine commutator comprising a linear displacement sensor, characterized in that: The measuring instrument further comprises a probe, an analog data processor and a display instrument, the probe is arranged at the measuring end of the linear displacement sensor, the signal output end of the linear displacement sensor is connected to the signal input end of the analog data processor, the analog data processor converts the voltage signal output by the linear displacement sensor into length data and then transmits the length data to the display instrument.

2. An ovality gauge for an AC machine slip ring or a DC machine commutator according to claim 1, characterized in that: The probe is a roller or a roller pin.

3. Ellipsometry apparatus for the measurement of ellipticity of an electrical machine slip ring or commutator according to claim 1 or 2, characterized in that: The linear displacement sensor comprises a shell, a variable resistance slide rail and a sliding block, the variable resistance slide rail is arranged in the shell, the sliding block is arranged on the variable resistance slide rail and moves along the variable resistance slide rail, the sliding block extends out of the end face of the shell and is provided with a connecting rod, and the probe is arranged at the end face of the connecting rod.

4. An ovality gauge for an AC machine slip ring or a DC machine commutator according to claim 3, characterised in that: The measuring instrument further comprises a clamping head, the clamping head is arranged at the end face of the connecting rod, and the probe is clamped by the clamping head.

5. An ovality gauge for an AC machine slip ring or a DC machine commutator as defined in claim 1, characterized by: The display instrument is provided with a storage chip and a USB interface, the storage chip stores measurement data, and the USB interface is connected to an external data storage device to realize the export of the measurement data.

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