Method for testing uniform load characteristic of high-speed heavy-load planetary gear train

Abstract

The invention provides a method for testing the uniform load characteristic of a high-speed heavy-load planetary gear train. According to the method, the uniform load coefficient under the low-speed working condition is corrected through the dynamic load coefficient under the high-speed working condition and the dynamic load coefficient under the low-speed working condition, and the corrected uniform load coefficient under the actual high-speed working condition is obtained. The uniform load test cost in the fields of aero-engines, gas turbines, large-scale wind power generation equipment and the like can be reduced, the safety and reliability in the uniform load test process are improved, and the survival rate of the strain gauges is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-speed and heavy-load planetary gear transmission, and in particular to a method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train. Background Art

[0002] In today's industrial field, high-speed and heavy-duty planetary gear transmission systems are widely used, from power transmission of aerospace vehicles to speed increasers of large wind power generation equipment to drive systems of high-speed trains. Its operating reliability and stability are directly related to the performance and operational safety of the entire equipment.

[0003] When the planetary gear transmission system is working, uniform load distribution between the planetary gears is the key factor to ensure its efficient, stable and long-life operation. Once the load distribution is uneven, it will cause many serious problems. For example, if some planetary gears are subjected to excessive loads, it will accelerate the wear of the tooth surface, shorten the life of the gears, and greatly increase the maintenance cost and downtime of the equipment; at the same time, uneven loads may also cause the system vibration to intensify, which will not only generate additional noise pollution, but also may cause resonance, causing damage to the entire transmission system and even the equipment structure connected to it, threatening the operation safety.

[0004] However, the existing high-speed and heavy-load planetary gear transmission load-balancing test faces many challenges. Traditional testing methods usually require testing under actual high-speed rated conditions, that is, to test the load-balancing performance by loading at the same time according to the high speed and rated torque when the equipment is running. This process requires extremely complex and expensive testing equipment, because in order to simulate the high-speed operation state, there are extremely high requirements for the power source, bearings, lubrication system and measurement and control system of the test bench. On the one hand, the dynamic effects such as centrifugal force and gyroscopic torque brought by high speed make the design and manufacturing of the test system soar, and the high-precision speed control device and stable and reliable support structure are expensive; on the other hand, in order to accurately measure the load distribution of each planetary gear at high speed, it is necessary to equip it with high-frequency response and high-precision sensors, and the supporting data acquisition and processing system must also have powerful real-time computing capabilities to capture the ever-changing load changes, which undoubtedly further increases the testing cost.

[0005] In addition, testing under high speed rated conditions is extremely risky. Once an accident occurs during the test, such as sudden gear failure or poor lubrication, the huge inertia force generated by high-speed operation can easily cause serious damage to the equipment and even endanger the personal safety of on-site operators. Moreover, the preparation period for each test is long, including equipment

[0006] Steps such as debugging, preheating, and status monitoring have greatly reduced testing efficiency and are unable to meet the rapid development of modern industry's demand for efficient product research and development and quality inspection.

[0007] In order to solve the above problems, an innovative testing method is urgently needed that can overcome the disadvantages of high-speed testing and fully consider the key factors of high-speed working conditions. Summary of the invention

[0008] The purpose of the present invention is to provide a method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train to solve the problems existing in the prior art.

[0009] The technical solution adopted to achieve the purpose of the present invention is as follows: a method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train, comprising the following steps:

[0010] 1) Set up a loading test bench. The loading test bench includes a test bench base, a power input unit, a transmission unit, a load unit and a control and measurement unit. The power input unit, the transmission unit and the load unit are installed and fixed on the test bench base. The power input unit includes a drive motor 1 and a coupling Ⅰ2 connected in sequence. The transmission unit includes a speed-increasing gearbox 3, a gear transmission device 4 to be tested and a reduction gearbox 5 connected in sequence. The gear transmission device 4 to be tested is a planetary gear train. A connecting shaft Ⅰ6 and a coupling Ⅱ7 are provided between the speed-increasing gearbox 3 and the gear transmission device 4 to be tested. A coupling Ⅲ8 and a connecting shaft Ⅱ9 are provided between the gear transmission device 4 to be tested and the reduction gearbox 5. The load unit includes a load motor 10. A coupling Ⅳ11 is provided between the load motor 10 and the reduction gearbox 5. The control and measurement unit includes a control cabinet and a data acquisition system. The control cabinet is used to control the operation of the drive motor 1 and the loading of the load motor 10. The drive motor 1 provides power input for the test bench to drive the gear transmission device 4 to be tested to operate. The load motor 10 is used as a loading device to provide reverse torque to the gear transmission device 4 under test, ensuring that the system operates under loading. The data acquisition system includes a torque speed sensor and a strain gauge. The torque speed sensor is suspended and installed on the coupling II 7 and the coupling III 8, and is used to measure the output torque and speed in real time.

[0011] 2) A strain gauge is pasted on the end face of the planetary gear of the gear transmission device 4 to be tested.

[0012] 3) Use low speed rated torque condition instead of high speed rated torque condition to realize the load-balanced test content. High speed heavy load planetary gear transmission gearbox is based on low speed N low The gearbox operates under the condition of rated input torque T, and the strain data is collected in real time during operation, and converted into dynamic meshing force through post-processing.

[0013] 4) Calculate the load-balancing coefficient B of each gear according to the dynamic meshing force of each gear low .

[0014] 5) Calculate the dynamic load coefficient K of each gear at high speed and rated torque conditions Vhigh ,by

[0015] And the dynamic load factor K under low speed rated torque conditions Vlow .

[0016] 6) Introduce the dynamic load factor to correct the load-balancing factor. Select the corrected load-balancing factor B for low speed rated torque conditions. low 'Approximately represents the load factor B of high speed rated torque condition high .

[0017] Furthermore, strain gauges are respectively pasted in the tangential and radial directions at the corresponding positions of the driven wheel at the output end, wherein two strain gauges are pasted at each theoretical synchronous meshing position.

[0018] Furthermore, holes are opened at corresponding positions of the planetary gear and the planetary gear shaft to meet the wiring requirements of the strain gauge signal output line.

[0019] Further, in step 4), the load sharing factor is calculated as follows:

[0020]

[0021] In formula (1), To participate in the meshing force of the gears on the left and right sides of the external and internal meshing herringbone teeth, is the load-averaging coefficient of the branches on the left and right sides of the external and internal meshing herringbone gears, The dynamic load-balancing coefficient of the left and right sides of the herringbone gear external and internal meshing is: is the load-balancing factor for each gear stage.

[0022] Further, in step 5), the dynamic load coefficient is calculated as follows:

[0023]

[0024] In formula (2), F t is the nominal tangential force of the meshing pair, b is the tooth width, v is the tangential velocity, z 1 is the number of teeth on the driving gear, and u is the gear ratio.

[0025] Further, in step 6), the load-sharing factor B of the low-speed rated torque condition after correction is low 'It can approximately represent the load factor B of high speed rated torque condition high , which can be expressed as the following formula:

[0026]

[0027] In formula (3), B low K is the load-sharing factor before correction for low speed rated torque condition. Vlow K is the dynamic load factor of low speed rated torque condition, Vhigh B is the dynamic load factor of low speed rated torque condition, low ' is the load-balancing coefficient obtained by simultaneously correcting the load-balancing coefficient of the low speed rated torque condition by the dynamic load coefficient of the high speed rated torque condition and the dynamic load coefficient of the low speed rated torque condition, B high It is the load sharing factor before correction for low speed rated torque condition.

[0028] The technical effects of the present invention are unquestionable:

[0029] A. There is no need to build a high-precision, high-cost test bench that can withstand complex dynamic effects such as high-speed centrifugal force and gyroscopic torque, which reduces the dependence on high-end power sources, special bearings, precision lubrication systems, and high-performance measurement and control systems, and significantly reduces equipment procurement and manufacturing costs.

[0030] B. Avoid many design problems caused by high speed, such as complex support structure, high-precision speed control device, etc., so that the test system structure is simpler, easier to build and maintain, and shorten the test system development cycle.

[0031] C. At low speeds, the frequency response and accuracy requirements for sensors are relatively relaxed. There is no need to equip high-frequency response, ultra-high-precision and expensive sensors to meet the load distribution measurement needs and reduce sensor procurement costs.

[0032] D. When running at low speed, even if there are emergencies such as gear failure and poor lubrication, the risk of equipment damage is greatly reduced due to the small inertia force. At the same time, it can effectively protect the personal safety of on-site operators and reduce potential accident hazards.

[0033] E. A method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train can reduce the cost of load-sharing testing in fields such as aircraft engines, gas turbines, and large wind power generation equipment, improve the safety and reliability of the load-sharing testing process, and increase the survival rate of strain gauges. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of a method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train;

[0035] Figure 2 Load the test bench configuration for the test system;

[0036] Figure 3 The signal acquisition and processing process for wireless strain load-sharing characteristic test;

[0037] Figure 4 Arrangement of the measuring points of the driven wheel and the pasting position of the strain gauge;

[0038] Figure 5 The positions of each pair of gears in a certain type of high-speed and heavy-load star gear system;

[0039] Figure 6 is the mean effective value of the meshing force of a certain type of high-speed and heavy-load star gear system;

[0040] Figure 7 is the mean value of meshing force amplitude of a certain type of high-speed and heavy-load star gear system;

[0041] Figure 8 Comparison of load-sharing coefficients before error correction for a certain type of high-speed and heavy-load star gear system;

[0042] Fig. 9 Comparison of load-sharing coefficients after error correction for a certain type of high-speed and heavy-load star gear system.

[0043] In the figure: driving motor 1, coupling Ⅰ2, speed increasing gearbox 3, gear transmission device under test 4, speed reducing gearbox 5, connecting shaft Ⅰ6, coupling Ⅱ7, coupling Ⅲ8, connecting shaft Ⅱ9, load motor 10, coupling Ⅳ11. DETAILED DESCRIPTION

[0044] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and customary means in the art, which should all be included in the protection scope of the present invention.

[0045] Embodiment 1:

[0046] This embodiment provides a method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train. Figure 1 , including the following steps:

[0047] 1) Set up a loading test bench. Figure 2As shown, the loading test bench includes a test bench base, a power input unit, a transmission unit, a load unit and a control and measurement unit. The power input unit, the transmission unit and the load unit are installed and fixed on the test bench base. The power input unit includes a drive motor 1 and a coupling Ⅰ2 connected in sequence. The transmission unit includes a speed-increasing gearbox 3, a gear transmission device 4 to be tested and a reduction gearbox 5 connected in sequence. The gear transmission device 4 to be tested is a planetary gear train. A connecting shaft Ⅰ6 and a coupling Ⅱ7 are provided between the speed-increasing gearbox 3 and the gear transmission device 4 to be tested. A coupling Ⅲ8 and a connecting shaft Ⅱ9 are provided between the gear transmission device 4 to be tested and the reduction gearbox 5. The load unit includes a load motor 10. A coupling Ⅳ11 is provided between the load motor 10 and the reduction gearbox 5. The control and measurement unit includes a control cabinet and a data acquisition system. The control cabinet is used to control the operation of the drive motor 1 and the loading of the load motor 10. The drive motor 1 provides power input for the test bench to drive the gear transmission device 4 to be tested to operate. The load motor 10 is used as a loading device to provide reverse torque to the gear transmission device 4 under test, ensuring that the system operates under loading. The data acquisition system includes a torque speed sensor and a strain gauge. The torque speed sensor is suspended and installed on the coupling II 7 and the coupling III 8, and is used to measure the output torque and speed in real time.

[0048] 2) Paste strain gauges on the end faces of the planetary gears of the gear transmission device 4 to be tested. In this embodiment, a wireless strain gauge is used to test the load-sharing characteristics. The test signal transmission-transmission-collection-processing process is as follows: Figure 3 When installing the strain gauge, the actual structure of the planetary gear must be considered, and combined with the wiring requirements of the strain gauge signal output line, holes should be opened at the corresponding positions of the planetary gear and the planetary gear shaft to meet the wiring requirements.

[0049] Because the gear module of the high-speed and heavy-load planetary gear transmission system is too small, the actual installation process does not have the conditions for pasting strain gauges between the teeth. In addition, because the input shaft of the driving wheel gear must be connected to the connecting shaft, the strain signal cannot be transmitted on the input shaft of the driving wheel gear by installing an oil-electric slip ring; based on this, in the load-sharing performance test scheme, the purpose of the load-sharing performance test of the core engine reducer is achieved by pasting strain gauges on the end faces of the five driven wheels. During the load-sharing performance test, strain gauges are pasted in the tangential and radial directions of the corresponding positions of the output driven wheel, where 2 strain gauges are pasted at each theoretical synchronous meshing position, and 2 measuring points are arranged symmetrically at 180° on the end face of each driven wheel on one side, and each measuring point is arranged with 1 strain gauge at the tangential position and radial position, respectively, and a total of 4 strain gauges are arranged at the 2 measuring points on one side. Therefore, a total of 8 strain gauges are arranged on both sides of each driven wheel; the core engine reducer has a total of 5 driven wheels, a total of 20 measuring points, and a total of 40 strain gauges need to be arranged. The arrangement of each driven wheel measuring point and the pasting position of the strain gauge are shown in the figure. Figure 4 shown.

[0050] 3) Use low speed rated torque condition instead of high speed rated torque condition to realize the load-balanced test content. High speed heavy load planetary gear transmission gearbox is based on low speed N low The gearbox is operated under rated input torque T, and the strain data is collected in real time during operation, and converted into dynamic meshing force through post-processing. Figure 5 shown.

[0051] A high-speed and heavy-load star gear transmission system operates at high speed conditions with Nhigh=11713r / min, P=3MW, and operates at low speed conditions with Nlow=1000r / min, T=2446Nm. The strain data collected during operation is used to convert the dynamic meshing force.

[0052] The effective value and amplitude of the dynamic meshing force of each gear at high and low speed conditions are as follows: Figure 6 and Figure 7 shown.

[0053] 3.1) The average effective value of the dynamic meshing force of each gear at high speed and rated torque conditions is: the first-stage left gear is 6444.5N, the first-stage right gear is 6434.1N, the second-stage left gear is 7200.1N and the second-stage right gear is 7201.7N.

[0054] The average effective values ​​of the dynamic meshing force of each gear at low speed and rated torque conditions are: 6426.2N for the first-stage left gear, 6425.7N for the first-stage right gear, 7191.5N for the second-stage left gear and 7191.4N for the second-stage right gear.

[0055] 3.2) The average amplitude of dynamic meshing force of each gear at high speed and rated torque conditions is: 1772.3N for the first-stage left gear, 1610.2N for the first-stage right gear, 1317.4N for the second-stage left gear and 1239.3N for the second-stage right gear.

[0056] The average amplitude of dynamic meshing force of each gear at low speed and rated torque conditions: the first stage left gear is 85.5N, the first stage right gear is 84.5N, and the second stage left gear is 84.9N

[0057] And the second-stage right gear is 91.5N.

[0058] According to the analysis results of the mean value of the effective value and amplitude of the meshing force, it can be seen that the effective value of the dynamic meshing force of the low-speed rated torque and high-speed rated torque of a certain type of high-speed heavy-load star gear system is basically equal, and the dynamic meshing force amplitude of the low-speed rated torque is much lower than the dynamic meshing force amplitude of the high-speed rated torque. It can be further known that using the low-speed rated torque instead of the high-speed rated torque in the load-balanced test can ensure that the calculation results of the two working conditions are valid, and the low dynamic meshing force amplitude of the low-speed rated torque will not accelerate the wear and fatigue of the gears.

[0059] 4) Calculate the load-balancing coefficient B of each gear according to the dynamic meshing force of each gear low The calculation formula of the load-average coefficient is shown in formula (1).

[0060]

[0061] In formula (1), To participate in the meshing force of the gears on the left and right sides of the external and internal meshing herringbone teeth, is the load-averaging coefficient of the branches on the left and right sides of the external and internal meshing herringbone gears, The dynamic load-balancing coefficient of the left and right sides of the herringbone gear external and internal meshing is: is the load-balancing factor for each gear stage.

[0062] 4.1) The load-averaging coefficients of each gear stage under high speed and rated torque conditions are: 1.2333 for the first-stage left gear, 1.1598 for the first-stage right gear, 1.1566 for the second-stage left gear, and 1.1385 for the second-stage right gear.

[0063] 4.2) The load-averaging coefficients of each gear stage under low speed rated torque conditions are: the first stage left gear is 1.1463, the first stage right gear is 1.0609, the second stage left gear is 1.0598, and the second stage right gear is 1.0628.

[0064] 4.3) It can be seen that the calculated average load coefficient errors of each gear under the two working conditions of high speed rated torque and low speed rated torque are: 7.05% for the first-stage left gear, 8.53% for the first-stage right gear, 8.39% for the second-stage left gear, and 6.65% for the second-stage right gear.

[0065] 4.4) It can be seen that the load sharing factor and error calculated for the two working conditions of high speed rated torque and low speed rated torque are as follows: Figure 8 As shown, although the errors are within 10%, there is still a certain gap.

[0066] 5) Calculate the dynamic load coefficient K of each gear at high speed and rated torque conditions Vhigh , and the dynamic load factor K under low speed rated torque conditions Vlow, the dynamic load coefficient calculation formula (2) is as follows.

[0067]

[0068] In formula (2), F t is the nominal tangential force of the meshing pair, b is the tooth width, v is the tangential velocity, z 1 is the number of teeth on the driving gear, and u is the gear ratio.

[0069] 5.1) The dynamic load coefficients of each gear at high speed and rated torque are: 1.09834 for the first-stage left gear, 1.09851 for the first-stage right gear, 1.09371 for the second-stage left gear, and 1.09379 for the second-stage right gear.

[0070] 5.2) The dynamic load coefficients of each gear at low speed and rated torque are: 1.01837 for the first-stage left gear, 1.0839 for the first-stage right gear, 1.01543 for the second-stage left gear, and 1.01548 for the second-stage right gear.

[0071] 6) Introduce the dynamic load coefficient to correct the load-balancing coefficient; select the corrected load-balancing coefficient B of the low-speed rated torque condition low 'Approximately represents the load factor B of high speed rated torque condition high , as shown in formula (3).

[0072]

[0073] In formula (3), B low K is the load-sharing factor before correction for low speed rated torque condition. Vlow K is the dynamic load factor of low speed rated torque condition, Vhigh B is the dynamic load factor of low speed rated torque condition, low ' is the load-balancing coefficient obtained by simultaneously correcting the load-balancing coefficient of the low speed rated torque condition by the dynamic load coefficient of the high speed rated torque condition and the dynamic load coefficient of the low speed rated torque condition, B high The load factor before correction for low speed rated torque condition

[0074] 6.1) The load-averaging coefficient of each gear at high speed and rated torque is: 1.2333 for the first-stage left gear, 1.1598 for the first-stage right gear, 1.1566 for the second-stage left gear, and 1.1385 for the second-stage right gear.

[0075] 6.2) The load-sharing coefficients under the actual high-speed operating condition after correction of the low-speed rated torque operating condition are: the first-stage left gear is 1.2363, the first-stage right gear is 1.1444, the second-stage left gear is 1.1413, and the second-stage right gear is 1.1447.

[0076] 6.3) It can be seen that the errors of the load-balancing coefficient under high-speed rated torque and the load-balancing coefficient under actual high-speed conditions after correction of the low-speed rated torque conditions are: 0.24% for the first-stage left gear, 1.33% for the first-stage right gear, 1.32% for the second-stage left gear, and 0.54% for the second-stage right gear.

[0077] 6.4) It can be seen that the load-balancing factor of the high-speed rated torque condition and the corrected load-balancing factor and error of the low-speed rated torque condition are as follows: Fig. 9 As shown, the maximum error is 1.33%, indicating that the load averaging factor calculated under the low-speed rated torque condition after correction can represent the load averaging factor calculated under the high-speed rated torque condition. Further, it is recognized that the load averaging factor calculated under the low-speed rated torque condition after correction can represent the load averaging factor calculated under the high-speed rated torque condition, which is beyond the ability and level of ordinary technicians in this field.

[0078] The present embodiment discloses a method for testing the load-sharing characteristics of a high-speed and heavy-loaded planetary gear system. A wireless strain is used to test the load-sharing characteristics under low-speed rated torque conditions. The extracted tooth root strain is converted into a dynamic meshing force through strain data collected during operation. The load-sharing coefficient is calculated through the dynamic meshing force. The dynamic load coefficients under high-speed and low-speed conditions are calculated respectively. The dynamic load coefficient is introduced to correct the load-sharing coefficient, and finally the load-sharing coefficient corrected by the dynamic load coefficient is obtained.

[0079] Embodiment 2:

[0080] This embodiment provides a relatively basic implementation method, a high-speed heavy-load planetary gear train load-sharing characteristic test method, see Figure 1 , including the following steps:

[0081] 1) Set up a loading test bench. Figure 2As shown, the loading test bench includes a test bench base, a power input unit, a transmission unit, a load unit and a control and measurement unit. The power input unit, the transmission unit and the load unit are installed and fixed on the test bench base. The power input unit includes a drive motor 1 and a coupling Ⅰ2 connected in sequence. The transmission unit includes a speed-increasing gearbox 3, a gear transmission device 4 to be tested and a reduction gearbox 5 connected in sequence. The gear transmission device 4 to be tested is a planetary gear train. A connecting shaft Ⅰ6 and a coupling Ⅱ7 are provided between the speed-increasing gearbox 3 and the gear transmission device 4 to be tested. A coupling Ⅲ8 and a connecting shaft Ⅱ9 are provided between the gear transmission device 4 to be tested and the reduction gearbox 5. The load unit includes a load motor 10. A coupling Ⅳ11 is provided between the load motor 10 and the reduction gearbox 5. The control and measurement unit includes a control cabinet and a data acquisition system. The control cabinet is used to control the operation of the drive motor 1 and the loading of the load motor 10. The drive motor 1 provides power input for the test bench to drive the gear transmission device 4 to be tested to operate. The load motor 10 is used as a loading device to provide reverse torque to the gear transmission device 4 under test, ensuring that the system operates under loading. The data acquisition system includes a torque speed sensor and a strain gauge. The torque speed sensor is suspended and installed on the coupling II 7 and the coupling III 8, and is used to measure the output torque and speed in real time.

[0082] 2) Paste strain gauges on the end faces of the planetary gears of the gear transmission device 4 to be tested. In this embodiment, a wireless strain gauge is used to test the load-sharing characteristics. The test signal transmission-transmission-collection-processing process is as follows: Figure 3 When installing the strain gauge, the actual structure of the planetary gear must be considered, and combined with the wiring requirements of the strain gauge signal output line, holes should be opened at the corresponding positions of the planetary gear and the planetary gear shaft to meet the wiring requirements.

[0083] Because the gear module of the high-speed and heavy-load planetary gear transmission system is too small, the actual installation process does not have the conditions for pasting strain gauges between the teeth. In addition, because the input shaft of the driving wheel gear must be connected to the connecting shaft, the strain signal cannot be transmitted on the input shaft of the driving wheel gear by installing an oil-electric slip ring; based on this, in the load-sharing performance test scheme, the purpose of the load-sharing performance test of the core engine reducer is achieved by pasting strain gauges on the end faces of the five driven wheels. During the load-sharing performance test, strain gauges are pasted in the tangential and radial directions of the corresponding positions of the output driven wheel, where 2 strain gauges are pasted at each theoretical synchronous meshing position, and 2 measuring points are arranged symmetrically at 180° on the end face of each driven wheel on one side, and each measuring point is arranged with 1 strain gauge at the tangential position and radial position, respectively, and a total of 4 strain gauges are arranged at the 2 measuring points on one side. Therefore, a total of 8 strain gauges are arranged on both sides of each driven wheel; the core engine reducer has a total of 5 driven wheels, a total of 20 measuring points, and a total of 40 strain gauges need to be arranged. The arrangement of each driven wheel measuring point and the pasting position of the strain gauge are shown in the figure. Figure 4 shown.

[0084] 3) High speed heavy load planetary gear transmission gearbox according to low speed N low The gearbox is operated under rated input torque T, and the strain data is collected in real time during operation, and converted into dynamic meshing force through post-processing. Figure 5 shown.

[0085] A high-speed and heavy-load star gear transmission system operates at high speed conditions with Nhigh=11713r / min, P=3MW, and operates at low speed conditions with Nlow=1000r / min, T=2446Nm. The strain data collected during operation is used to convert the dynamic meshing force.

[0086] The effective value and amplitude of the dynamic meshing force of each gear at high and low speed conditions are as follows: Figure 6 and Figure 7 shown.

[0087] 3.1) The average effective value of the dynamic meshing force of each gear at high speed and rated torque conditions is: the first-stage left gear is 6444.5N, the first-stage right gear is 6434.1N, the second-stage left gear is 7200.1N and the second-stage right gear is 7201.7N.

[0088] The average effective value of dynamic meshing force of each gear at low speed and rated torque:

[0089] The first-stage left gear is 6426.2N, the first-stage right gear is 6425.7N, the second-stage left gear is 7191.5N and the second-stage right gear is 7191.4N.

[0090] 3.2) The average amplitude of dynamic meshing force of each gear at high speed and rated torque conditions is: 1772.3N for the first-stage left gear, 1610.2N for the first-stage right gear, 1317.4N for the second-stage left gear and 1239.3N for the second-stage right gear.

[0091] The average amplitude of dynamic meshing force of each gear at low speed and rated torque conditions is: 85.5N for the first-stage left gear, 84.5N for the first-stage right gear, 84.9N for the second-stage left gear and 91.5N for the second-stage right gear.

[0092] According to the analysis results of the mean value of the effective value and amplitude of the meshing force, it can be seen that the effective value of the dynamic meshing force of the low-speed rated torque and high-speed rated torque of a certain type of high-speed heavy-load star gear system is basically equal, and the dynamic meshing force amplitude of the low-speed rated torque is much lower than the dynamic meshing force amplitude of the high-speed rated torque. It can be further known that using the low-speed rated torque instead of the high-speed rated torque in the load-balanced test can ensure that the calculation results of the two working conditions are valid, and the low dynamic meshing force amplitude of the low-speed rated torque will not accelerate the wear and fatigue of the gears.

[0093] 4) Calculate the load-balancing coefficient B of each gear according to the dynamic meshing force of each gear low .

[0094] 4.1) The load-averaging coefficients of each gear stage under high speed and rated torque conditions are: 1.2333 for the first-stage left gear, 1.1598 for the first-stage right gear, 1.1566 for the second-stage left gear, and 1.1385 for the second-stage right gear.

[0095] 4.2) The load-averaging coefficients of each gear stage under low speed rated torque conditions are: the first stage left gear is 1.1463, the first stage right gear is 1.0609, the second stage left gear is 1.0598, and the second stage right gear is 1.0628.

[0096] 4.3) It can be seen that the calculated average load coefficient errors of each gear under the two working conditions of high speed rated torque and low speed rated torque are: 7.05% for the first-stage left gear, 8.53% for the first-stage right gear, 8.39% for the second-stage left gear, and 6.65% for the second-stage right gear.

[0097] 4.4) It can be seen that the load sharing factor and error calculated for the two working conditions of high speed rated torque and low speed rated torque are as follows: Figure 8 As shown, although the errors are within 10%, there is still a certain gap.

[0098] 5) Calculate the dynamic load coefficient K of each gear at high speed and rated torque conditions Vhigh , and the dynamic load factor K under low speed rated torque conditions Vlow .

[0099] 5.1) The dynamic load coefficients of each gear at high speed and rated torque are: the first stage left gear is 1.09834, the first stage right gear is 1.09851, the second stage left gear is 1.09371,

[0100] The second stage right gear is 1.09379.

[0101] 5.2) The dynamic load coefficients of each gear at low speed and rated torque are: 1.01837 for the first-stage left gear, 1.0839 for the first-stage right gear, 1.01543 for the second-stage left gear, and 1.01548 for the second-stage right gear.

[0102] 6) Introduce the dynamic load coefficient to correct the load-balancing coefficient; select the corrected load-balancing coefficient B of the low-speed rated torque condition low 'Approximately represents the load factor B of high speed rated torque condition high .

[0103] 6.1) The load-averaging coefficient of each gear at high speed and rated torque is: 1.2333 for the first-stage left gear, 1.1598 for the first-stage right gear, 1.1566 for the second-stage left gear, and 1.1385 for the second-stage right gear.

[0104] 6.2) The load-sharing coefficients under the actual high-speed operating condition after correction of the low-speed rated torque operating condition are: the first-stage left gear is 1.2363, the first-stage right gear is 1.1444, the second-stage left gear is 1.1413, and the second-stage right gear is 1.1447.

[0105] 6.3) It can be seen that the errors of the load-balancing coefficient under high-speed rated torque and the load-balancing coefficient under actual high-speed conditions after correction of the low-speed rated torque conditions are: 0.24% for the first-stage left gear, 1.33% for the first-stage right gear, 1.32% for the second-stage left gear, and 0.54% for the second-stage right gear.

[0106] 6.4) It can be seen that the load-balancing factor of the high-speed rated torque condition and the corrected load-balancing factor and error of the low-speed rated torque condition are as follows: Fig. 9 As shown, the maximum error is 1.33%, indicating that the load averaging factor calculated under the low-speed rated torque condition after correction can represent the load averaging factor calculated under the high-speed rated torque condition. Further, it is recognized that the load averaging factor calculated under the low-speed rated torque condition after correction can represent the load averaging factor calculated under the high-speed rated torque condition, which is beyond the ability and level of ordinary technicians in this field.

[0107] Embodiment 3:

[0108] The main steps of this embodiment are the same as those of Embodiment 2. Furthermore, in step 4), the load sharing coefficient is calculated using the following formula:

[0109]

[0110] In formula (1), To participate in the meshing force of the gears on the left and right sides of the external and internal meshing herringbone teeth, is the load-averaging coefficient of the branches on the left and right sides of the external and internal meshing herringbone gears, The dynamic load-balancing coefficient of the left and right sides of the herringbone gear external and internal meshing is: is the load-balancing factor for each gear stage.

[0111] Embodiment 4:

[0112] The main steps of this embodiment are the same as those of Embodiment 2. Furthermore, in step 5), the dynamic load coefficient is calculated using the following formula:

[0113]

[0114] In formula (2), F t is the nominal tangential force of the meshing pair, b is the tooth width, v is the tangential velocity, z 1 is the number of teeth on the driving gear, and u is the gear ratio.

[0115] Embodiment 5:

[0116] The main steps of this embodiment are the same as those of embodiment 2. Further, in step 6), the load-sharing factor B of the low-speed rated torque working condition after correction is low 'It can approximately represent the load factor B of high speed rated torque condition high , which can be expressed as the following formula:

[0117]

[0118] In formula (3), B low K is the load-sharing factor before correction for low speed rated torque condition. Vlow K is the dynamic load factor of low speed rated torque condition, Vhigh B is the dynamic load factor of low speed rated torque condition, low ' is the load-balancing coefficient obtained by simultaneously correcting the load-balancing coefficient of the low speed rated torque condition by the dynamic load coefficient of the high speed rated torque condition and the dynamic load coefficient of the low speed rated torque condition, B high It is the load sharing factor before correction for low speed rated torque condition.

Claims

1. A method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train, characterized in that: The following steps are involved: 1) Setting up the loading test bench; the loading test bench comprises a test bench base, a power input unit, a transmission unit, a load unit and a control and measurement unit; the power input unit, the transmission unit and the load unit are mounted and fixed on the test bench base; the power input unit comprises a driving motor 1 and a coupling Ⅰ2 connected in sequence; the transmission unit comprises a speed increasing gearbox 3, a gear transmission device 4 to be tested and a speed reducing gearbox 5 connected in sequence; the gear transmission device 4 to be tested is a planetary gear train; a connecting shaft Ⅰ6 and a coupling Ⅱ7 are arranged between the speed increasing gearbox 3 and the gear transmission device 4 to be tested; the gear transmission device 4 to be tested and A coupling III8 and a connecting shaft II9 are arranged between the reduction gearbox 5; the load unit includes a load motor 10; a coupling IV11 is arranged between the load motor 10 and the reduction gearbox 5; the control and measurement unit includes a control cabinet and a data acquisition system; the control cabinet is used to control the operation of the drive motor 1 and the loading of the load motor 10; the drive motor 1 provides power input for the test bench to drive the gear transmission device 4 under test to operate; the data acquisition system includes a torque and speed sensor and a strain gauge; the torque and speed sensor is suspended and installed on the coupling II7 and the coupling III8, and is used to measure the output torque and speed in real time; 2) Paste the strain gauge on the end face of the driven wheel of the gear transmission device 4 to be tested; 3) Use low speed rated torque condition instead of high speed rated torque condition to realize the load-balanced test content; high speed heavy load planetary gear transmission gearbox is based on low speed N low and rated input torque T, during which strain data is collected in real time and converted into dynamic meshing force through post-processing; 4) Calculate the load-balancing coefficient B of each gear according to the dynamic meshing force of each gear low ; 5) Calculate the dynamic load coefficient K of each gear at high speed and rated torque conditions Vhigh , and the dynamic load factor K under low speed rated torque conditions Vlow ; 6) Introduce the dynamic load coefficient to correct the load-balancing coefficient; select the corrected load-balancing coefficient B of the low-speed rated torque condition low 'Approximately represents the load factor B of high speed rated torque condition high .

2. A method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train according to claim 1, characterized in that: Strain gauges are respectively pasted in the tangential and radial directions at the corresponding positions of the driven wheel at the output end; wherein, two strain gauges are pasted at each theoretical synchronous meshing position.

3. A method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train according to claim 1 -1- The method is characterized in that: Holes are opened at corresponding positions on the planetary gear and the planetary gear shaft to meet the wiring requirements of the strain gauge signal output line.

4. A method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train according to claim 1, characterized in that: In step 4), the load sharing factor is calculated as follows: In formula (1), To participate in the meshing force of the gears on the left and right sides of the external and internal meshing herringbone teeth, is the load-averaging coefficient of the branches on the left and right sides of the external and internal meshing herringbone gears, The dynamic load-balancing coefficient of the left and right sides of the herringbone gear external and internal meshing is: is the load-balancing factor for each gear stage.

5. A method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train according to claim 1, characterized in that: In step 5), the dynamic load coefficient is calculated as follows: In formula (2), F t is the nominal tangential force of the meshing pair, b is the tooth width, v is the tangential speed, z1 is the number of teeth of the driving gear, and u is the gear ratio.

6. A method for testing the load-sharing characteristics of a high-speed and heavy-load planetary gear train according to claim 1, characterized in that: The load factor B of the low speed rated torque condition after correction in step 6) low 'It can approximately represent the load factor B of high speed rated torque condition high , which can be expressed as the following formula: In formula (3), B low K is the load-sharing factor before correction for low speed rated torque condition. Vlow K is the dynamic load factor of low speed rated torque condition, Vhigh B is the dynamic load factor of low speed rated torque condition, low ' is the load-balancing coefficient obtained by simultaneously correcting the load-balancing coefficient of the low speed rated torque condition by the dynamic load coefficient of the high speed rated torque condition and the dynamic load coefficient of the low speed rated torque condition, B high It is the load sharing factor before correction for low speed rated torque condition.

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