SERVO DRIVE TEST STAND

Abstract

This utility model relates to devices for servo drive diagnostics and repair. The technical result is a reduction in time and labor costs (resources). This is achieved by the stand's housing, which features three non-latching control buttons on the front. An on / off switch and 5V power supply wires are mounted on one end of the housing. A servo drive connector is mounted on the opposite end of the housing. A control board based on an NE 555 microcircuit is also mounted within the housing.

Description

[0001] The utility model relates to devices for diagnostics and repair of servo drives.

[0002] A test rig for electric drives is known [RU Patent No. 2737738, IPC G01M 13 / 02, G01R 31 / 34, published 02.12.2020], including a load drive, the output link of which is designed with the possibility of kinematic connection with the output link of the electric drive being tested and is equipped with a torque sensor, and an automatic control system connected to the load drive, designed with the possibility of operator control and having an input and an output, the input of the automatic control system is connected to the torque sensor, characterized in that the output link of the load drive is additionally equipped with a position sensor connected to the input of the automatic control system, the load drive includes a load asynchronous electric motor equipped with a digital speed sensor connected to the input of the automatic control system, an electromagnetic brake clutch,installed on the rotor of the load asynchronous electric motor and connected to the output of the automatic control system and a wave reducer with intermediate rolling elements, wherein the automatic control system is connected by the output to the stator of the load asynchronous motor through a frequency converter and is designed with the possibility of connection to the control unit of the electric drive being tested.

[0003] The disadvantages are the lack of the ability to adjust the position of the servo shaft and the lack of a power source, you have to use a laboratory one, or any other handy 5V one.

[0004] The technical result is a reduction in time and labor costs (resources).

[0005] The technical result is achieved due to the fact that the stand includes a housing, on the front part of which three control buttons without locking are installed, and on one end side there is an on / off switch and wires for a 5V power source are brought out, on the opposite side of the body there is a connector for connecting a servo drive, and a control board on an NE 555 microcircuit is fixed in the housing.

[0006] Let's look at an example of how the stand works.

[0007] By electrically connecting the connector on the servo harness and the corresponding connector on the test bench, the servo is connected to the test bench.

[0008] When the servo motor is turned on, the servo output shaft starts to rotate.

[0009] A valve designed for ventilation of the battery is connected to the servo shaft to control it.

[0010] Working with servo drives requires precise control signal tuning. A PWM (pulse-width modulation) signal is required to control the servo drive. The pulse duration determines the angle of rotation of the shaft. The current shaft position is determined by the current resistance value of the servo drive's potentiometer. The control electronics compare the received signal and the resistance. If there is a discrepancy, the control unit supplies power to the motor, rotating the shaft in the desired direction. The control unit strives to achieve and maintain a resistance on the potentiometer that best matches the angle specified by the incoming signal.

[0011] The signal bus master oscillator is an NE 555 microcircuit. The control board of the test bench is assembled around this microcircuit using the multivibrator principle. Inside the case is a PWM generator control board based on the NE 555 microcircuit, which interacts with the servo drive by supplying a PWM signal of varying duration / duty cycle.

[0012] All elements inside the case are connected by soldering with “POS-60 Tin”.

[0013] The NE 555 control board is firmly installed in the enclosure using screws. The buttons and servo connector are soldered to the board using standard soldering. The on / off button is soldered with wires. The power supply wires are soldered to the enclosure button. The NE 555 control board communicates with the servo control board installed in the servo enclosure by supplying a PWM (pulse-width modulation) signal with varying pulse durations / duty cycles.

[0014] The stand is made in a plastic case 1019.

[0015] The stand has three non-latching buttons, which, when pressed with a finger, connect three corresponding resistors that set three different PWM signal pulse durations.

[0016] The first two signals set the servo positions to 0° and 180°.

[0017] By rotating the connected servo drive from one extreme position to the other, the operation of the servo drive's gear reducer is checked. This identifies defective servo drives with faulty gears (broken or bent teeth on any gear reducer gear, axial or radial runout of the gear reducer gears, etc.). After checking the servo drive's performance, the third button is pressed, which sets the servo drive precisely to the closed position. This position is necessary when installing the battery ventilation mechanism. Set to the closed position, the servo drive is connected to the damper, which is also set to the closed position. This eliminates the possibility of ventilation system errors when turning on the battery, speeding up battery assembly and testing. Reinstalling the servo drive connected to the damper is a long and labor-intensive process.

[0018] With the servo drive connected, turn on the stand's power and press the button marked "1" with your finger. This will generate a pulse width signal corresponding to one extreme position of the servo drive. The servo drive will rotate to the corresponding extreme position. If it was already in this position before pressing the button, it will not rotate and will remain in place. Next, press the button marked "2" and the stand will generate a pulse width signal corresponding to the opposite shaft position. During rotation, the operator listens to the sound emitted by the servo drive's gearbox. If the sound is smooth and monotonous, operating without jamming or stopping, the servo drive is functioning properly. By alternately pressing buttons "1" and "2," the operator rotates the servo drive from one extreme position to the other, observing its operation. If a defect is detected, the servo drive is removed from production and sent for disposal.This allows the servo drive's functionality to be determined before installation on the battery. Installing and removing the servo drive from the battery is a labor-intensive process. This saves time in battery production if a defect is detected. When testing the servo drive, buttons "1" and "2" are used to determine whether the servo drive is defective or not. Once the servo drive is determined to be usable, button "3" is pressed, and the test bench generates a signal with a PWM pulse duration corresponding to the servo drive's "closed" position. The servo drive is then sent to the battery installation station, where the shutter is also set to the closed position and then connected to the servo drive. This test bench feature eliminates the need to "guess" the servo drive by connecting it to the shutter. This significantly saves time in battery production, as there is no need to repeatedly remove and install the servo drive while trying to find the "closed" position.