A test fixture and method for planetary gear reducer

Abstract

The application provides a kind of test tool and method for planetary gear reducer, test tool for planetary gear reducer includes the mounting frame for fixing the body of planetary gear reducer to be measured, servo motor and control panel respectively, and the test method of test tool for planetary gear reducer includes system reset, parameter setting, start running, signal acquisition and observation, automatic determination etc., the test tool and method for planetary gear reducer provided by the application, speed measurement is carried out using photoelectric speed sensor with reflector and lamp strip, speed-lights preset in PLC controller in control panel conversion algorithm, through signal sampling, frequency conversion, proportional mapping and quantization determination etc., the number of pulse signals collected by photoelectric speed sensor in unit time is converted into equivalent light number, further improve the accuracy of measurement.

Description

Technical Field

[0001] This invention relates to the field of industrial automated production and mechanical transmission, and in particular to a testing fixture and method for planetary gear reducers. Background Technology

[0002] In the field of industrial automation production and mechanical transmission, planetary gear reducers, as a key transmission component, are widely used in various mechanical equipment, such as robot joint drives, CNC machine tool spindle drives, and precision transmission systems of aerospace equipment, due to their significant advantages such as high precision, high torque density, and compact structure.

[0003] Currently, there are many limitations in the testing methods and tooling for planetary gear reducers. Traditional testing methods often combine manual operation with simple instrument measurement. For example, when testing the output speed of a planetary gear reducer, a handheld tachometer is usually used. During the measurement, the tester needs to be in close contact with the testing equipment, which poses certain safety hazards.

[0004] In terms of testing fixtures, existing testing devices are often simple in structure and have limited functions. For example, for testing the output speed of planetary gear reducers, some testing fixtures lack an effective speed detection mechanism and cannot obtain output speed data in real time and accurately; or they use contact speed sensors for measurement. During long-term use, contact sensors are prone to wear due to direct contact with the tested component, which leads to increased measurement errors and may even affect the normal operation of the planetary gear reducer.

[0005] In addition, most existing testing fixtures do not have real-time monitoring and alarm functions. During the testing process, if the planetary gear reducer malfunctions, such as the output speed exceeding the set range or abnormal vibration, the testers will find it difficult to detect and take corresponding measures in time. This will lead to further damage to the equipment, affect the production schedule, increase maintenance costs, and cause inconvenience to actual use.

[0006] Therefore, it is necessary to provide a new testing fixture and method for planetary gear reducers to solve the above-mentioned technical problems. Summary of the Invention

[0007] To solve the above-mentioned technical problems, the present invention provides a testing fixture and method for planetary gear reducers.

[0008] The test fixture for planetary gear reducers provided by this invention includes: mounting brackets for fixing the planetary gear reducer body under test, a servo motor, and a control panel; the servo motor is connected to the input sun gear shaft of the planetary gear reducer body via a coupling; the control panel contains a PLC controller; the servo motor is electrically connected to the PLC controller; and the fixture also includes:

[0009] The test turntable assembly includes a fixed plate, a turntable, and a clamping plate. The fixed plate is mounted on a mounting frame, and the turntable is fixedly connected to the output shaft of the planetary gear reducer body through the clamping plate and rotates synchronously with the output shaft.

[0010] The speed sensing component includes a photoelectric speed sensor, a reflector, and a light strip. The light strip is attached to the inner circumference of the fixed disk, and there are N light strips. The N light strips are evenly distributed along the inner circumference of the fixed disk. The reflector is fixedly installed on the outer circumference of the turntable. The photoelectric speed sensor is fixed on the fixed disk and faces the rotation trajectory of the reflector on the outer circumference of the turntable.

[0011] An alarm mechanism includes a buzzer, which is mounted on a control panel and electrically connected to the output of a PLC controller.

[0012] Preferably, the number N of the light strips is four, and the four light strips are evenly distributed on the outer periphery of the turntable at a 90-degree angle. The control panel is equipped with an HMI touch screen, a speed setting knob, a start button, a stop button, a system reset button, a pass indicator light, and a fail indicator light. The PLC controller has a preset speed-light count conversion algorithm, which is used to convert the number of pulse signals collected by the photoelectric speed sensor per unit time into an equivalent number of lights. The specific operation steps of the speed-light count conversion algorithm are as follows:

[0013] Step 1, Signal Sampling: The PLC controller is set to a fixed sampling time window. The window The time is greater than or equal to 1 second, in the window Inside, a photoelectric speed sensor captures the light pulse signals generated when the reflector passes by in real time and counts the total number of pulses;

[0014] Step 2, Frequency Conversion: Based on the total number of pulses and sampling time Calculate the pulse frequency corresponding to the actual output speed. :

[0015] The calculation formula is:

[0016] ;

[0017] Step 3, Proportional Mapping: Establish a standard mapping relationship. At a standard input speed of 100 RPM, the reducer output shaft generates N pulses per revolution. The corresponding standard pulse frequency is denoted as... At this point, calculate the equivalent number of lit lights (Count);

[0018]

[0019] Step 4: Quantitative Judgment: The calculated equivalent number of lit lights, Count, is rounded up or down. If Count equals 4 lights, it is judged as qualified; if Count is less than 4 lights, it is judged as unqualified.

[0020] If the calculation result is a decimal, the PLC determines it to be a critical value and triggers an early warning; if the calculation result is an integer but less than 4, it is directly determined to be unqualified.

[0021] Preferably, a bracket is fixed to the top of the mounting bracket, and a speed sensor for detecting the speed of the servo motor is provided on the surface of the bracket. The speed sensor is electrically connected to the PLC controller.

[0022] Preferably, it also includes a load simulation component, which is a magnetic powder brake connected to the end of the output shaft of the planetary gear reducer body via a coupling.

[0023] A test method for a planetary gear reducer with testing fixtures includes the following steps:

[0024] S1. System Reset: Turn on the main power supply, and the operator presses the system reset button. The PLC performs a self-test, and all indicator lights on the control panel flash once and then turn off.

[0025] S2. Parameter setting: After the reset is complete, set the input target speed to 100 RPM via the HMI touch screen or knob; if a load test is required, set the torque value of the magnetic powder brake to the rated output torque of the reducer.

[0026] S3. Start-up: After the parameters are set, press the start button. The servo motor accelerates the rotation of the sun gear of the planetary gear reducer. After the input shaft speed stabilizes at 100 RPM, the output shaft of the reducer drives the turntable to rotate.

[0027] S4. Signal Acquisition and Observation: When the turntable rotates, the photoelectric speed sensor detects the light signal of the reflector in real time and converts it into a pulse signal, which is then transmitted to the PLC. The operator simultaneously observes the status of the light strip or reflector on the outer periphery of the turntable.

[0028] S5. Automatic Judgment: At this time, the PLC calculates the number of lights lit per unit time based on the judgment logic, that is, the number of lights corresponding to valid pulses:

[0029] The determination logic is as follows:

[0030]

[0031] in, For PLC to perform sampling within a fixed time window The total number of light pulse signals actually captured. This represents the theoretical total number of pulses under standard operating conditions. Corresponding to the four light strips on the inner periphery of the fixed plate, each time the turntable rotates once, a single reflector passes through four detection positions in sequence, generating four pulses.

[0032] The judgment rules are as follows:

[0033] If the calculation result Count=4, that is, the actual number of pulses. satisfy If the result is within the allowable error range, it is considered qualified. The green light on the control panel will illuminate and the buzzer will sound briefly.

[0034] If the calculation result is Count 4, which is the actual number of pulses. If the result is not met, the red light on the control panel will illuminate and the buzzer will sound a continuous alarm.

[0035] S6. Manual verification and unloading: The operator visually verifies whether the actual lighting status matches the panel indication. If they match, the operator presses the stop button, the servo motor decelerates and stops, and the product is removed after the turntable stops. The product is recorded as qualified. If the number of lights fluctuates between 3 and 4, it is judged as borderline unqualified. The operator returns to step S3 for retesting. If the retest fails, the product is recorded as unqualified.

[0036] S7. Data Recording: Based on the test results, the system automatically records the test time, input speed, calculated number of lights on and equivalent speed, and generates a test report.

[0037] Preferably, in step S5, the number of lights directly corresponds to the output shaft speed of the planetary gear reducer body. At the standard speed, the number of lights is 4, and the number of lights decreases as the speed slows down.

[0038] Preferably, in step S5, the calculation logic for the number of lit lights is as follows: the PLC calculates the number of lights within a fixed sampling time window. The number of high-level pulses captured by the photoelectric speed sensor is counted. If the number of pulses corresponds to the number of times the reflector passes through the sensor, which meets the standard speed requirement of 4 cycles, it is recorded as 4 pulses. If the number of pulses corresponds to 3 cycles or less, it is recorded as unqualified.

[0039] Preferably, in step S4, if the light strip exhibits a high-frequency stable flashing state, it is considered qualified, and this is recorded as phenomenon A; if the light strip exhibits a state where the flashing frequency is significantly slower, the light is dim, or it is constantly lit without flashing, it is considered unqualified, and this is recorded as phenomenon B.

[0040] Preferably, it also includes critical alarm logic. When the number of lights calculated by the PLC fluctuates around the set threshold, including alternating between the number of lights equal to 3 and the number of lights equal to 4 within 3 consecutive sampling cycles, the system triggers a yellow warning light to flash, prompting the operator to pay close attention or conduct a retest.

[0041] Preferably, the servo motor has encoder feedback. In step S3, the PLC will only allow the judgment logic of step S4 to be started if the error between the actual speed fed back by the encoder and the set speed of 100 RPM is less than ±1%. Otherwise, the servo motor will perform PID automatic adjustment or alarm shutdown.

[0042] Compared with related technologies, the testing fixture and method for planetary gear reducers provided by this invention have the following advantages:

[0043] 1. Traditional testing methods for measuring the output speed of planetary gear reducers often use handheld tachometers, requiring testers to be in close contact with the testing equipment, which poses a significant safety hazard. In contrast, this invention uses a non-contact speed sensing component. The photoelectric speed sensor measures the speed by detecting the light signal reflected by a reflector, eliminating the need for testers to directly contact the equipment. This effectively avoids safety accidents caused by close-range operation and greatly improves the safety of the testing process.

[0044] 2. This invention incorporates an alarm mechanism. The buzzer is electrically connected to the output of the PLC controller. The PLC controller can receive speed data from the photoelectric speed sensor in real time and compare it with a preset speed range. When the output speed exceeds the set range, the PLC controller immediately controls the buzzer to sound an alarm, reminding the test personnel to handle the abnormal situation in time. Multiple alarm methods, such as a long or short buzzer, the on / off status of the pass / fail indicator lights, and the flashing of the yellow warning light, can quickly remind the test personnel to take appropriate measures, effectively preventing further damage to the equipment, reducing production losses, and improving production efficiency.

[0045] 3. This invention uses a photoelectric speed sensor in conjunction with a reflector and LED strip for speed measurement, avoiding physical contact between the sensor and the measured component, reducing the impact of wear on measurement accuracy. Furthermore, the PLC controller in the control panel has a preset speed-to-light count conversion algorithm. Through signal sampling, frequency conversion, proportional mapping, and quantization judgment, the number of pulse signals collected by the photoelectric speed sensor per unit time is converted into an equivalent number of lights, and the test result is accurately determined based on the number of lights, further improving the accuracy of the measurement. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the overall structure of the test fixture for the planetary gear reducer provided by the present invention;

[0047] Figure 2 This is a schematic diagram of the overall structure of the test fixture for the planetary gear reducer provided by the present invention;

[0048] Figure 3 A schematic flowchart illustrating the testing method for the planetary gear reducer using the testing fixture provided by this invention.

[0049] The following are the labels in the diagram: 1. Mounting bracket; 11. Servo motor; 12. Planetary gear reducer body; 121. Coupling 1; 122. Coupling 2; 13. Bracket; 2. Speed ​​sensor; 3. Control panel; 31. Buzzer; 4. Fixed plate; 41. Turntable; 411. Reflector; 42. Clamping plate; 43. LED strip; 5. Photoelectric speed sensor. Detailed Implementation

[0050] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0051] Please refer to the following: Figures 1 to 3 ,in, Figure 1 This is a schematic diagram of the overall structure of the test fixture for the planetary gear reducer provided by the present invention; Figure 2 This is a schematic diagram of the overall structure of the test fixture for the planetary gear reducer provided by the present invention; Figure 3 A schematic flowchart illustrating the testing method for the planetary gear reducer using the testing fixture provided by this invention.

[0052] In some embodiments, a test fixture for a planetary gear reducer, such as Figures 1 to 2 As shown, the system includes mounting brackets 1 for fixing the planetary gear reducer body 12, servo motor 11, and control panel 3. The servo motor 11 is connected to the input sun gear shaft of the planetary gear reducer body 12 via coupling 121. The control panel 3 contains a PLC controller, and the servo motor 11 is electrically connected to the PLC controller. The system also includes:

[0053] The test turntable assembly includes a fixed plate 4, a turntable 41 and a clamping plate 42. The fixed plate 4 is mounted on the mounting bracket 1. The turntable 41 is fixedly connected to the output shaft of the planetary gear reducer body 12 through the clamping plate 42 and rotates synchronously with the output shaft.

[0054] The speed sensing component includes a photoelectric speed sensor 5, a reflector 411, and a light strip 43. The light strip 43 is attached to the inner circumference of the fixed disk 4, and there are N light strips 43. The N light strips 43 are distributed at equal intervals along the inner circumference of the fixed disk 4. The reflector 411 is fixedly installed on the outer circumference of the turntable 41. The photoelectric speed sensor 5 is fixed on the fixed disk 4 and faces the rotation trajectory of the reflector 411 on the outer circumference of the turntable 41.

[0055] Among them, the photoelectric speed sensor 5 is model LG-9200, and its specific working principle will not be described in detail here;

[0056] An alarm mechanism includes a buzzer 31, which is mounted on a control panel 3 and electrically connected to the output of a PLC controller.

[0057] Specifically, traditional testing methods for measuring the output speed of planetary gear reducers often use handheld tachometers, requiring testers to be in close contact with the testing equipment, which poses a significant safety hazard. In contrast, this invention uses a non-contact speed sensing component. The photoelectric speed sensor 5 measures the speed by detecting the light signal reflected by the reflector 411, eliminating the need for testers to directly contact the equipment. This effectively avoids safety accidents caused by close-range operation and greatly improves the safety of the testing process.

[0058] Furthermore, this invention incorporates an alarm mechanism. The buzzer 31 is electrically connected to the output of the PLC controller. The PLC controller can receive the speed data from the photoelectric speed sensor 5 in real time and compare it with the preset speed range. When the output speed exceeds the set range, the PLC controller immediately controls the buzzer 31 to sound an alarm, reminding the test personnel to handle the abnormal situation in time. The buzzer 31 has multiple alarm modes, such as a long or short beep, the on / off state of the pass and fail indicator lights, and the flashing of the yellow warning light. These can quickly remind the test personnel to take appropriate measures, effectively preventing further damage to the equipment, reducing production losses, and improving production efficiency.

[0059] Furthermore, this invention employs a photoelectric speed sensor 5 in conjunction with a reflector 411 and a light strip 43 for speed measurement, avoiding physical contact between the sensor and the measured component, reducing the impact of wear on measurement accuracy. In addition, the PLC controller within the control panel 3 has a preset speed-to-light count conversion algorithm. Through signal sampling, frequency conversion, proportional mapping, and quantization judgment, the number of pulse signals collected by the photoelectric speed sensor 5 per unit time is converted into an equivalent number of lights, and the test result is accurately determined based on the number of lights, further improving the accuracy of the measurement.

[0060] In some embodiments, reference is made to Figures 1 to 2 As shown, the number N of the light strips 43 is four. The four light strips 43 are evenly distributed on the outer periphery of the turntable 41 at a 90-degree angle. The control panel 3 is equipped with an HMI touch screen, an input speed setting knob, a start button, a stop button, a system reset button, a pass indicator light, and a fail indicator light. The PLC controller has a preset speed-light count conversion algorithm, which is used to convert the number of pulse signals collected by the photoelectric speed sensor 5 per unit time into an equivalent number of lights. The specific operation steps of the speed-light count conversion algorithm are as follows:

[0061] Step 1, Signal Sampling: The PLC controller is set to a fixed sampling time window. ,window The time is greater than or equal to 1 second, in the window Inside, the photoelectric speed sensor 5 captures the light pulse signal generated when the reflector 411 passes by in real time and counts the total number of pulses;

[0062] Step 2, Frequency Conversion: Based on the total number of pulses obtained. and sampling time Calculate the pulse frequency corresponding to the actual output speed. :

[0063] The calculation formula is:

[0064] ;

[0065] Step 3, Proportional Mapping: Establish a standard mapping relationship. At a standard input speed of 100 RPM, the reducer output shaft generates N pulses per revolution. The corresponding standard pulse frequency is denoted as... At this point, calculate the equivalent number of lit lights (Count);

[0066]

[0067] Step 4: Quantitative Judgment: The calculated equivalent number of lit lights, Count, is rounded up or down. If Count equals 4 lights, it is judged as qualified; if Count is less than 4 lights, it is judged as unqualified.

[0068] If the calculation result is a decimal, such as 3.5~3.9, the PLC determines it to be a critical value and triggers an alarm; if the calculation result is an integer but less than 4, it is directly determined to be unqualified.

[0069] The top of the mounting bracket 1 is also fixed with a bracket 13, and the surface of the bracket 13 is also provided with a speed sensor 2 for detecting the speed of the servo motor 11. The speed sensor 2 is electrically connected to the PLC controller.

[0070] Among them, the speed sensor 2 can be a fiber optic sensor;

[0071] It also includes a load simulation component, which is a magnetic powder brake. The magnetic powder brake is connected to the end of the output shaft of the planetary gear reducer body 12 via coupling 122, and is used to simulate the load condition of the planetary gear reducer body 12 under rated torque.

[0072] Specifically, the following analysis is provided regarding the algorithm for converting rotation speed to the number of lights on:

[0073] For example, when the turntable 41 rotates, the reflector 411 moves accordingly. With each rotation, the reflector 411 will pass through the detection areas corresponding to the four light strips 43 or scan the four photoelectric speed sensors 5 in sequence, generating four light pulse signals.

[0074] At this time, the servo motor 11 drives the input shaft of the reducer, and the output shaft drives the turntable 41 to rotate. The reflector 411 fixed on the turntable 41 rotates through the area of ​​the light strip 43 on the fixed plate 4. The photoelectric speed sensor 5 captures the light signal reflected by the reflector 411 and converts it into an electrical pulse signal to be transmitted to the PLC.

[0075] Note: In the standard structure, with one reflector 411, four LED strips 43, or four photoelectric speed sensors 5, the photoelectric speed sensor 5 will generate four pulse signals or one pulse representing four counting units for each rotation of the turntable 41, depending on the installation method of the photoelectric speed sensor 5. This embodiment takes the generation of four pulses as an example.

[0076] Step 1 Sampling: PLC sets the sampling window T1 = 1 second;

[0077] Step 2: Frequency Counting: Count the total number of pulses within 1 second. For example, at standard speed: =4, then the frequency is: =4Hz;

[0078] Step 3 Mapping: PLC retrieves standard parameters: When inputting 100 RPM, the standard frequency... =4Hz, number of LED strips N=4;

[0079] Calculation formula: = ,because =1s, and =4Hz, at this time If the actual rotational speed decreases, for example: =3, then =3 lamps;

[0080] Step 4: After mapping is completed, the PLC rounds the Count.

[0081] If Count = 4 → qualified, the green light will illuminate and the buzzer will sound 31 times.

[0082] If Count = 3, 2, 1, 0 → not qualified, the red light will illuminate and buzzer 31 will sound continuously.

[0083] If 3.5 ≤ Count < 4 → Critical warning, the yellow light will flash, indicating a retest;

[0084] It should be noted that the speed sensor 2 monitors the input speed. The PLC will only start the above-mentioned judgment logic when the input speed is stable at 100 RPM ±1% to eliminate input fluctuation interference.

[0085] Furthermore, this method converts the rotation speed deviation into an intuitive number of lights. Operators do not need to stare at the digital display screen; they only need to look at the light strip 43 next to the turntable 41 or the indication on the control panel 3 to determine whether the product is qualified. Four lights indicate qualification, while fewer lights indicate failure, which greatly reduces labor intensity and improves testing efficiency.

[0086] Furthermore, by setting up critical value warnings and manual verification steps, it effectively prevents misjudgments caused by sensor jitter or momentary interference, and also has an input speed self-check function.

[0087] In some embodiments, a test method for a planetary gear reducer with test fixtures is described, with reference to... Figures 1 to 3 As shown, it includes the following steps:

[0088] S1. System Reset: Turn on the main power supply, and the operator presses the system reset button. The PLC performs a self-test, and all indicator lights on control panel 3 flash once and then turn off.

[0089] S2. Parameter setting: After the reset is complete, set the input target speed to 100 RPM via the HMI touch screen or knob; if a load test is required, set the torque value of the magnetic powder brake to the rated output torque of the reducer.

[0090] S3. Start-up: After the parameters are set, press the start button. The servo motor 11 accelerates and drives the sun gear of the planetary gear reducer body 12 to rotate. After the input shaft speed stabilizes at 100 RPM, the reducer output shaft drives the turntable 41 to rotate.

[0091] S4. Signal Acquisition and Observation: When the turntable 41 rotates, the photoelectric speed sensor 5 detects the light signal of the reflector 411 in real time and converts it into a pulse signal to be transmitted to the PLC. The operator simultaneously observes the status of the light strip 43 or reflector 411 on the outer periphery of the turntable 41.

[0092] If the light strip 43 exhibits a high-frequency, stable flashing state, it is considered qualified and this is recorded as phenomenon A; if the light strip 43 exhibits a significantly slower flashing frequency, dim light, or constant light without flashing, it is considered unqualified and this is recorded as phenomenon B.

[0093] S5. Automatic Judgment: At this time, the PLC calculates the number of lights lit per unit time according to the judgment logic, that is, the number of lights lit corresponding to the valid pulses.

[0094] The decision logic is as follows:

[0095]

[0096] in, For PLC to perform sampling within a fixed time window The total number of light pulse signals actually captured. This represents the theoretical total number of pulses under standard operating conditions. Corresponding to the four light strips 43 on the inner periphery of the fixed disk 4, each time the turntable 41 rotates once, a single reflector 411 passes through four detection positions in sequence and generates four pulses.

[0097] The judgment rules are as follows:

[0098] If the calculation result Count=4, that is, the actual number of pulses. satisfy If the result is within the allowable error range, it is considered qualified. The green light on control panel 3 will illuminate, and buzzer 31 will sound a short beep.

[0099] If the calculation result is Count 4, which is the actual number of pulses. If the result is not met, the red light on control panel 3 will illuminate and buzzer 31 will sound a continuous alarm.

[0100] It is worth noting that the number of lights illuminated directly corresponds to the output shaft speed of the planetary gear reducer body 12. At the standard speed, there are 4 lights illuminated, and the number of lights illuminated decreases as the speed decreases.

[0101] It is worth noting that the calculation logic for the number of lit lights is as follows: the PLC operates within a fixed sampling time window. Within the sensor, the number of high-level pulses captured by the photoelectric speed sensor 5 is counted. If the number of pulses corresponds to the number of times the reflector 411 passes through the sensor, which meets the standard speed requirement of 4 cycles, then it is recorded as 4 pulses; if the number of pulses corresponds to 3 cycles or less, then it is recorded as unqualified.

[0102] S6. Manual verification and unloading: The operator visually verifies whether the actual lighting status matches the panel indication. If they match, the operator presses the stop button, the servo motor 11 decelerates and stops, and the product is removed after the turntable 41 stops. The product is recorded as qualified. If the number of lights fluctuates between 3 and 4, it is judged as critically unqualified. The operator returns to step S3 for retesting. If the retest fails, the product is recorded as unqualified.

[0103] S7. Data Recording: Based on the test results, the system automatically records the test time, input speed, calculated number of lights on and equivalent speed, and generates a test report.

[0104] It also includes critical alarm logic. When the number of lights calculated by the PLC fluctuates around the set threshold, including alternating between the number of lights equaling 3 and the number of lights equaling 4 within 3 consecutive sampling cycles, the system triggers a yellow warning light to flash, prompting the operator to pay close attention or conduct a retest.

[0105] The servo motor 11 has encoder feedback. In step S3, the PLC will only allow the judgment logic of step S4 to be started if the error between the actual speed fed by the encoder and the set speed of 100 RPM is less than ±1%. Otherwise, the servo motor 11 will perform PID automatic adjustment or alarm shutdown.

[0106] Specifically, the following examples are analyzed:

[0107] Test scenario: Factory performance testing of a batch of planetary gear reducers, with input speed set at 100 RPM, standard number of lights on at 4, sampling time T1=1 second, and allowable error ±1%.

[0108] Case A (Qualified Product): The reducer output shaft drives the turntable 41 to rotate, and the PLC collects the number of pulses within 1 second. =4;

[0109] calculate: = =4; Count= =4.

[0110] Result: Count=4.

[0111] Action: The green light indicating qualification on control panel 3 remains constantly lit, and buzzer 31 emits a short beep;

[0112] Case B (Wearable Part): Another speed reducer experienced a 25% decrease in output speed due to gear wear. The PLC collected the number of pulses within 1 second. =3;

[0113] Calculation: Factual = 3 / 1 = 3Hz; Count = (3 / 4) × 4 = 3.

[0114] Result: Count=3 < 4.

[0115] Action: The red light on control panel 3 indicates a failure and remains constantly lit; buzzer 31 emits a continuous long alarm.

[0116] Case C (Critical Product): A speed reducer is on the verge of being qualified. The number of pulses fluctuates between 3 and 4 within 1 second, and the average count is calculated to be 3.6.

[0117] Result: 3.5 ≤ Count < 4.

[0118] Action: The yellow warning light on control panel 3 flashes, and the buzzer 31 emits intermittent beeping sounds. The operator visually confirms that the flashing frequency of the light strip 43 is slightly slower. Press the retest button, and the system will automatically retest once. If it is still at the critical value, it will be judged as unqualified.

[0119] The operator confirms that the lighting status of Case A is consistent with that of Control Panel 3, removes the product and places it in the qualified area; for Cases B and C, the stop button is pressed, the servo motor 11 decelerates and brakes, and after the turntable 41 stops, the clamp 42 is released and the product is removed and placed in the defective area; the PLC automatically generates an Excel report on the test time, input 100 RPM, number of lights 4, and qualified status of Case A and exports it to a USB flash drive to complete the test.

[0120] Furthermore, an input-output ratio conversion algorithm is adopted. Instead of simply comparing output speed, even if the input speed of servo motor 11 fluctuates slightly, such as 99-101 RPM, as long as the reduction ratio is normal, the number of lights will remain stable at 4, avoiding misjudgment. Furthermore, by adding a magnetic powder brake load component, the torque holding capability of the reducer can be tested under load. If the number of lights decreases or flickers unstable under load, it can be directly determined that the gear meshing is poor or the bearing is damaged.

[0121] The circuits and controls involved in this invention are all existing technologies and will not be described in detail here.

[0122] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A test fixture for a planetary gear reducer, comprising mounting brackets (1) for fixing the planetary gear reducer body (12), servo motor (11), and control panel (3) respectively, wherein the servo motor (11) is connected to the input sun gear shaft of the planetary gear reducer body (12) via a coupling (121), and the control panel (3) is equipped with a PLC controller, and the servo motor (11) is electrically connected to the PLC controller, characterized in that, Also includes: The test turntable assembly includes a fixed plate (4), a turntable (41) and a clamping plate (42). The fixed plate (4) is mounted on the mounting frame (1). The turntable (41) is fixedly connected to the output shaft of the planetary gear reducer body (12) through the clamping plate (42) and rotates synchronously with the output shaft. The speed sensing component includes a photoelectric speed sensor (5), a reflector (411), and a light strip (43). The light strip (43) is attached to the inner circumference of the fixed disk (4), and there are N light strips (43). The N light strips (43) are distributed at equal intervals along the inner circumference of the fixed disk (4). The reflector (411) is fixedly installed on the outer circumference of the turntable (41). The photoelectric speed sensor (5) is fixed on the fixed disk (4) and faces the rotation trajectory of the reflector (411) on the outer circumference of the turntable (41). An alarm mechanism includes a buzzer (31), which is mounted on a control panel (3) and electrically connected to the output of a PLC controller.

2. The test fixture for a planetary gear reducer according to claim 1, characterized in that, The number of light strips (43) is N, which is four. The four light strips (43) are evenly distributed on the outer periphery of the turntable (41) at a 90-degree angle. The control panel (3) is equipped with an HMI touch screen, an input speed setting knob, a start button, a stop button, a system reset button, a qualified indicator light, and a failed indicator light. The PLC controller has a preset speed-light count conversion algorithm, which is used to convert the number of pulse signals collected by the photoelectric speed sensor (5) per unit time into the equivalent number of lights. The specific operation steps of the speed-light count conversion algorithm are as follows: Step 1, Signal Sampling: The PLC controller is set to a fixed sampling time window. The window The time is greater than or equal to 1 second, in the window Inside, the photoelectric speed sensor (5) captures the light pulse signal generated when the reflector (411) passes by in real time and counts the total number of pulses; Step 2, Frequency Conversion: Based on the total number of pulses obtained. and sampling time Calculate the pulse frequency corresponding to the actual output speed. : Step 3, Proportional Mapping: Establish a standard mapping relationship. At a standard input speed of 100 RPM, the reducer output shaft generates N pulses per revolution. The corresponding standard pulse frequency is denoted as... At this point, calculate the equivalent number of lit lights (Count); Step 4: Quantitative Judgment: The calculated equivalent number of lit lights, Count, is rounded up or down. If Count equals 4 lights, it is judged as qualified; if Count is less than 4 lights, it is judged as unqualified. If the calculation result is a decimal, the PLC determines it to be a critical value and triggers an early warning; if the calculation result is an integer but less than 4, it is directly determined to be unqualified.

3. The test fixture for a planetary gear reducer according to claim 1, characterized in that, The top of the mounting bracket (1) is also fixed with a bracket (13), and the surface of the bracket (13) is also provided with a speed sensor (2) for detecting the speed of the servo motor (11), and the speed sensor (2) is electrically connected to the PLC controller.

4. The test fixture for a planetary gear reducer according to claim 1, characterized in that, It also includes a load simulation component, which is a magnetic powder brake, and the magnetic powder brake is connected to the end of the output shaft of the planetary gear reducer body (12) via coupling two (122).

5. A test method for a planetary gear reducer based on the test fixture described in any one of claims 1-4, characterized in that, Includes the following steps: S1, System Reset: Turn on the main power supply, the operator presses the system reset button, the PLC performs a self-test, and all indicator lights on the control panel (3) flash once and then turn off; S2. Parameter setting: After the reset is complete, set the input target speed to 100 RPM via the HMI touch screen or knob; if a load test is required, set the torque value of the magnetic powder brake to the rated output torque of the reducer. S3. Start-up: After the parameters are set, press the start button. The servo motor (11) accelerates the rotation of the sun gear of the planetary gear reducer body (12). After the input shaft speed stabilizes at 100 RPM, the output shaft of the reducer drives the turntable (41) to rotate. S4. Signal Acquisition and Observation: When the turntable (41) rotates, the photoelectric speed sensor (5) detects the light signal of the reflector (411) in real time and converts it into a pulse signal to be transmitted to the PLC. The operator simultaneously observes the status of the light strip (43) or reflector (411) on the outer periphery of the turntable (41). S5. Automatic Judgment: At this time, the PLC calculates the number of lights lit per unit time based on the judgment logic, that is, the number of lights corresponding to valid pulses: If the calculation result is equal to 4, it is judged as qualified. The green light of qualified on the control panel (3) will light up, and the buzzer (31) will sound a short beep. If the calculation result is less than 4, it is judged as unqualified. The unqualified red light on the control panel (3) will light up, and the buzzer (31) will sound a long alarm. S6. Manual verification and unloading: The operator visually verifies whether the actual lighting status matches the panel indication. If they match, the operator presses the stop button, the servo motor (11) decelerates and stops, and the product is removed after the turntable (41) stops. The product is recorded as a qualified product. If the number of lights fluctuates between 3 and 4, it is judged as a critical non-compliance. The operator returns to step S3 for retesting. If the retest fails, the product is recorded as a non-compliant product. S7. Data Recording: Based on the test results, the system automatically records the test time, input speed, calculated number of lights on and equivalent speed, and generates a test report.

6. The test method for the planetary gear reducer using the test fixture according to claim 5, characterized in that, In step S5, the number of lights directly corresponds to the output shaft speed of the planetary gear reducer body (12). At the standard speed, the number of lights is 4. As the speed decreases, the number of lights decreases.

7. The test method for the planetary gear reducer using the test fixture according to claim 6, characterized in that, In step S5, the calculation logic for the number of lit lights is as follows: the PLC operates within a fixed sampling time window. Inside, count the number of high-level pulses captured by the photoelectric speed sensor (5). If the number of pulses corresponds to the number of times the reflector (411) passes through the sensor, which meets the standard speed of 4 cycles, then it is recorded as 4 pulses; if the number of pulses corresponds to 3 cycles or less, then it is recorded as unqualified.

8. The test method for the planetary gear reducer using the test fixture according to claim 7, characterized in that, In step S4, if the light strip (43) exhibits a high-frequency stable flashing state, it is considered qualified and this is recorded as phenomenon A; if the light strip (43) exhibits a significantly slower flashing frequency, dim light, or constant light without flashing, it is considered unqualified and this is recorded as phenomenon B.

9. The test method for the planetary gear reducer using the test fixture according to claim 8, characterized in that, It also includes critical alarm logic. When the number of lights calculated by the PLC fluctuates around the set threshold, including alternating between the number of lights equaling 3 and the number of lights equaling 4 within 3 consecutive sampling cycles, the system triggers a yellow warning light to flash, prompting the operator to pay close attention or conduct a retest.

10. The test method for the planetary gear reducer using the test fixture according to claim 9, characterized in that, The servo motor (11) is equipped with encoder feedback. In step S3, the PLC will only allow the judgment logic of step S4 to be started when the error between the actual speed fed by the encoder and the set speed of 100 RPM is less than ±1%. Otherwise, the servo motor (11) will perform PID automatic adjustment or alarm shutdown.

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