A backlash detection device for planetary gear reducer

Abstract

A planetary gear reducer backlash detection device includes a detection platform, a high-precision servo motor is connected to the detection platform for lifting, the output end of the servo motor faces downward and is connected to a torque sensor and an input shaft from top to bottom in sequence, a reducer to be tested is fixed on the detection platform, which is located below the input shaft and has its output end facing downward, a clamping block for clamping and fixing the output shaft of the reducer to be tested is provided below the detection platform, the input shaft is connected to the input end of the reducer to be tested, and a high-precision encoder is fixed on the detection platform, and the encoder surrounds the outer ring of the input shaft. The structure of the invention is reasonable and compact, and the input shaft is connected to the reducer by controlling the lifting of the servo motor, and the required torque value is accurately obtained in combination with the torque sensor in the torque control mode, which is used to control the positive and negative torsional torque of the input shaft, and the high-precision encoder is used to detect the micro-angle rotation value of the input shaft, which is used to measure the micro backlash value of the reducer, accurately detect the backlash value, and accurately detect the detection.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and in particular to a reducer, and specifically to a backlash detection device for a planetary gear reducer. Background Art

[0002] At present, reducers are a kind of mechanical transmission device widely used in the industrial field. They match the speed and transmit torque between the prime mover, working machine or actuator. They include various types of gear reducers, planetary gear reducers, worm gear reducers, etc. Planetary gear reducers are mainly composed of planetary gears, sun gears, outer gear rings, etc. They are small in size, high in transmission efficiency, wide in reduction range, and high in transmission accuracy. They are widely used in transmission systems such as servo motors, stepper motors, and DC motors.

[0003] The parameters of planetary gear reducers mainly include backlash, efficiency, temperature rise, starting torque, etc. Backlash is the most important indicator of deceleration, and the size of the backlash directly determines the precision of the planetary gear reducer. Reducers with large backlash will produce cumulative positioning errors in the reciprocating motion of the equipment, affecting the positioning accuracy and service life of the equipment, and also generating large noise. Torque loading, as a key link in the reducer test, directly affects the accuracy of backlash measurement in the torque value loaded at the input end of the reducer. The loading method also affects the number of angles collected at each loading point, thereby affecting the reliability and accuracy of the test results. The traditional loading method has problems such as small amount of loading point angle collection, low degree of automation, and large influence of human errors. Therefore, it is necessary to specifically detect the backlash of the planetary gear reducer to ensure its normal and accurate detection. In order to solve the problem of backlash detection of planetary gear reducers, a planetary gear reducer backlash automatic detection device that can be used for backlash detection of reducers of different models and sizes is needed. Summary of the invention

[0004] The present invention aims to solve the problems existing in the above-mentioned prior art and provide a planetary gear reducer backlash detection device to solve the problems of inaccurate backlash detection and small application range of the current planetary gear reducer, and meet the demand for accurate detection of reducer backlash.

[0005] The present invention adopts a technical solution to solve its technical problems: This planetary gear reducer backlash detection device includes a detection platform, which is characterized in that: a precision servo control system is connected to the detection platform for lifting and lowering, and the precision servo control system includes a high-precision servo motor, a torque sensor and an encoder. The output end of the servo motor faces downward and is connected to the torque sensor, the input shaft and the encoder from top to bottom in sequence. A reducer to be tested is fixed on the detection platform, which is located below the input shaft and has its output end facing downward. A clamping block for clamping and fixing the output shaft of the reducer to be tested is provided below the detection platform, and the input shaft is connected to the input end of the reducer to be tested, and the encoder surrounds the outer ring of the input shaft.

[0006] The detection method using the planetary gear reducer backlash detection device is as follows:

[0007] A. Place the reducer to be inspected on the inspection platform with the output shaft facing downward. Slowly lower the servo motor until the input shaft is inserted into the input hole of the reducer. Press and fix the reducer and make the input shaft fit tightly with the reducer.

[0008] B. After the reducer is fixed, start the detection program and control the clamping block to clamp the output shaft of the reducer. The servo motor cooperates with the torque sensor to detect the backlash value in the torque control mode, that is, to generate a torque value of 2% of the rated torque of the reducer under test, and twist it clockwise with the input shaft. At this time, record the detection value R1 of the encoder, and then twist it counterclockwise with the input shaft with the same torque value, and record the detection value L1 of the high-precision encoder. The backlash value at this point is X1=R1-L1.

[0009] C. Loosen the clamping block, and drive the servo motor to rotate the reducer through an angle (usually 30 degrees or 60 degrees), repeat the above action, measure R2 and L2, and obtain the backlash value of the second point X2 = R2-L2. Similarly, within one rotation of the reducer, the backlash of each point is X1, X2, X3‥‥Xn, and the backlash value of the reducer is max{X1, X2, X3‥‥Xn}.

[0010] As a further improvement of the present invention, the clamping block is slidably connected to the bottom of the detection platform, and left and right screw rods driven by a motor are arranged under the detection platform, and the left and right sides of the left and right screw rods are respectively connected to the clamping block in a transmission manner. When the motor is controlled to rotate forward, the clamping blocks move relative to each other under the drive of the forward and reverse screw rods, clamping the output shaft of the reducer to play a positioning role; when the motor is reversed, the clamping blocks release the output shaft of the reducer.

[0011] As a further improvement of the present invention, the detection platform is provided with a connecting rod clamping mechanism located on both sides of the speed reducer to be detected, and the connecting rod clamping mechanism includes a clamping block located at the front end and pressed on the speed reducer. The connecting rod clamping mechanism includes a clamping block that can quickly press and fix the speed reducer, thereby reducing the installation workload during detection and reducing labor intensity.

[0012] As a further improvement of the present invention, a screw is provided on the top of the clamping block, a nut is threadedly connected to the screw, the screw passes through the top pressing end of the connecting rod clamping mechanism and is clamped and fixed by the upper and lower sides of the nut to form a lifting and lowering adjustment structure of the clamping block. After such a setting, the top pressing position of the clamping block can be adjusted by adjusting the position of the nut on the screw, and various types of reducers can be tested, and the scope of use is greatly expanded.

[0013] As a further improvement of the present invention, the detection platform is vertically fixed with a fixing plate, the servo motor is connected to the fixing plate by a screw rod structure, and the torque sensor and the encoder are connected and fixed to the fixing plate. The fixing plate is used to fix the servo motor, the torque sensor and the encoder, ensuring that the servo motor, the torque sensor and the encoder are fixed in the same straight line up and down.

[0014] As a further improvement of the present invention, the clamping end face of the clamping block is a V-shaped end face. The clamping block with a V-shaped end face can better use the output shafts of reducers of various specifications and sizes, has a wider range of use, and is more practical.

[0015] As a further improvement of the present invention, the servo motor and the torque sensor, as well as the torque sensor and the input shaft are connected via a coupling. The coupling connection can ensure connection stability, especially in rotation measurement, and minimize the adverse effects caused by unstable connection.

[0016] As a further improvement of the present invention, the precision servo control system is connected to the touch screen of the operating end through PLC, and the precision servo control system includes an emergency stop switch and a control switch. PLC control realizes the automation of backlash measurement, effectively reduces human errors, and cooperates with the touch screen to make the operation simpler and more convenient.

[0017] The beneficial effects of the present invention are as follows: the present invention has a reasonable and compact structure, connects the input shaft to the reducer by controlling the lifting of the servo motor, and works in conjunction with the torque sensor in the torque control mode to accurately obtain the required torque value, which is used to control the positive and negative torsion of the input shaft, and the high-precision encoder is used to detect the micro-angular rotation value of the input shaft, which is used to measure the micro backlash value of the reducer. Through the cooperation of the precision servo system and the torque sensor, automatic and precise loading is achieved through PLC control, and repeated measurement of the rated torque is achieved, thereby improving the measurement accuracy and reliability, and achieving good use effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention;

[0019] Figure 2 It is a right side view of the present invention;

[0020] Figure 3 It is a front view of the present invention;

[0021] Figure 4 for Figure 3 The cross-sectional view in the AA direction;

[0022] Figure 5 It is a schematic diagram of the torque control mode structure;

[0023] Figure 6 It is a structural diagram of the control system of the present invention.

[0024] Explanation of the reference numerals: detection platform 1, servo motor 2, torque sensor 3, input shaft 4, clamping block 5, encoder 6, left and right screw rods 7, clamping block 8, fixing plate 9, coupling 10. DETAILED DESCRIPTION

[0025] The present invention will be further described below in conjunction with the accompanying drawings:

[0026] Referring to the accompanying drawings: the planetary gear reducer backlash detection device in this embodiment includes a detection platform 1, which is characterized in that: the detection platform 1 is connected to a precision servo control system for lifting, and the precision servo control system includes a high-precision servo motor 2, a torque sensor 3 and an encoder 6. The output end of the servo motor 2 faces downward and is sequentially connected to the torque sensor 3, the input shaft 4 and the encoder 6 from top to bottom. The detection platform 1 is fixed with a reducer to be detected located below the input shaft 4 and with the output end facing downward. A clamping block 5 for clamping and fixing the output shaft of the reducer to be detected is provided below the detection platform 1. The input shaft 4 is connected to the input end of the reducer to be detected, and the encoder 6 surrounds the outer ring of the input shaft 4. The servo motor 2 and the torque sensor 3, and the torque sensor 3 and the input shaft 4 are all connected through a coupling 10.

[0027] The clamping end face of the clamping block 5 is a V-shaped end face.

[0028] The clamping block 5 is slidably connected to the bottom of the detection platform 1 . The bottom of the detection platform 1 is provided with left and right screw rods 7 driven by a motor. The left and right screw rods are respectively connected to the clamping block 5 in a transmission manner at their left and right sides.

[0029] The testing platform 1 is provided with connecting rod clamping mechanisms located on both sides of the speed reducer to be tested. The connecting rod clamping mechanisms include a clamping block 8 located at the front end and pressed against the speed reducer.

[0030] A screw is provided on the top of the clamping block 8, and a nut is threadedly connected to the screw. The screw passes through the top pressing end of the connecting rod clamping mechanism and is clamped and fixed by the upper and lower sides of the nut to form a lifting and lowering adjustment structure of the clamping block 8.

[0031] The detection platform 1 is vertically fixed with a fixing plate 9 , the servo motor 2 is connected to the fixing plate 9 by a screw rod structure, and the torque sensor 3 and the encoder 6 are both connected and fixed to the fixing plate 9 .

[0032] The precision servo control system is connected to the touch screen of the operation end through PLC. The precision servo control system includes an emergency stop switch and a control switch. The PLC model of this device is Mitsubishi FX2N-16MT. Figure 6As shown, PLC controls the servo driver to realize servo motor drive, and combines with the torque sensor to realize constant torque loading; PLC realizes multi-point automatic loading by controlling the servo driver and the stepper driver; the transmission and calculation of the measured angle data are realized through COM (RS485) and the precision encoder; the basic information of the measurement and the number of measurement loading points are input, and the measured data and curves are automatically output and saved.

[0033] The detection method is as follows: place the reducer to be tested on the detection platform 1 with the output shaft facing downward, slowly lower the servo motor 2 until the input shaft 4 is inserted into the input hole of the reducer, press and fix the reducer and make the input shaft 4 fit tightly with the reducer.

[0034] After the reducer is fixed, start the detection program and control the clamping block 5 to clamp the output shaft of the reducer. The servo motor 2 cooperates with the torque sensor to detect the backlash value in the torque control mode, that is, to generate a torque value of 2% of the rated torque of the reducer under test, and twist it clockwise with the input shaft. At this time, record the detection value R1 of the encoder, and then twist it counterclockwise with the input shaft with the same torque value, and record the detection value L1 of the high-precision encoder. The backlash value at this point is X1=R1-L1.

[0035] The clamping block 5 is loosened, and the reducer is driven by the servo motor to rotate an angle (usually 30 degrees or 60 degrees), and the above actions are repeated to measure R2 and L2, and the backlash value of the second point position is obtained as X2 = R2-L2. Similarly, within one rotation of the reducer, the backlash of each point is obtained as X1, X2, X3...Xn, and the backlash value of the reducer is max{X1, X2, X3...Xn}.

[0036] The torque control mode in the detection method is to input a 2% rated torque command of the reducer under test through the PLC. After the torque command is processed and resonance suppressed, the torque output is controlled by the system's built-in current control unit. At the same time, it is detected by the current sensor and adjusted in real time to achieve the first-level closed-loop control of the torque. After the motor outputs the torque, the torque sensor detects the torque output value and transmits it to the PLC controller. The PLC controller feeds back the torque detection value to the servo control system, which adjusts the output to achieve the second-level closed-loop control of the torque. The specific mode structure diagram is shown in the attached figure. Figure 5 shown.

[0037] Although the present invention has been shown and described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein within the scope of the claims.

Claims

1. A detection method for a backlash detection device of a planetary gear reducer, comprising a detection platform (1), a precision servo control system being connected to the detection platform (1) in a lifting manner, the precision servo control system comprising a high-precision servo motor (2), a torque sensor (3) and an encoder (6), the output end of the servo motor (2) facing downward and being sequentially connected to the torque sensor (3), an input shaft (4) and the encoder (6) from top to bottom, a reducer to be detected being located below the input shaft (4) and with the output end facing downward being fixed on the detection platform (1), a clamping block (5) for clamping and fixing the output shaft of the reducer to be detected being provided below the detection platform (1), the input shaft (4) being connected to the input end of the reducer to be detected, the encoder (6) surrounding the outer ring of the input shaft (4), the clamping block (5) being slidably connected below the detection platform (1), left and right screw rods (7) driven by a motor being provided below the detection platform (1), the left and right screw rods being respectively connected to the clamping block (5) on both sides in a transmission manner, The detection platform (1) is provided with a connecting rod clamping mechanism located on both sides of the inspected reducer, the connecting rod clamping mechanism comprises a clamping block (8) located at the front end and pressed on the reducer, a screw is provided on the top of the clamping block (8), a nut is threadedly connected to the screw, the screw passes through the top pressing end of the connecting rod clamping mechanism and is clamped and fixed by the upper and lower sides of the nut to form a lifting and lowering adjustment structure of the clamping block (8), the detection platform (1) is vertically fixed with a fixing plate (9), the servo motor (2) is connected to the fixing plate (9) by a screw structure, the torque sensor (3) and the encoder (6) are both connected to the fixing plate (9), the clamping end face of the clamping block (5) is a V-shaped end face, the servo motor (2) and the torque sensor (3), the torque sensor (3) and the input shaft (4) are connected by a coupling (10), the precision servo control system is connected to the touch screen of the operation end by a PLC, the precision servo control system comprises an emergency stop switch and a control switch, and the detection method steps are as follows: A. Place the reducer to be tested on the testing platform (1) with the output shaft facing downward, and slowly lower the servo motor (2) until the input shaft (4) is inserted into the input hole of the reducer. Press and fix the reducer and make the input shaft (4) fit tightly with the reducer. B. After the reducer is fixed, start the detection program, control the clamping block (5) to clamp the output shaft of the reducer, and the servo motor cooperates with the torque sensor (3) to detect the backlash value in the torque control mode, that is, to generate a torque value of 2% of the rated torque of the reducer under test, and twist it clockwise with the input shaft. At this time, record the detection value R1 of the encoder, and then twist it counterclockwise with the input shaft with the same torque value, and record the detection value L1 of the high-precision encoder. The backlash value at this point is X1=R1-L1; C. The clamping block is released, and the reducer is driven by the servo motor (2) to rotate through a predetermined angle. The above action is repeated to measure R2 and L2, and the backlash value of the second point is obtained as X2 = R2-L2. Similarly, within one rotation of the reducer, the backlash of each point is X1, X2, X3...Xn, and the backlash value of the reducer is max{X1, X2, X3...Xn}.

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