Test device for shaft torque loading test and loading test method

Abstract

The invention discloses a test device and a loading test method for a shaft torque loading test, and the loading test process is as follows: a driving motor rotates forwards to drive a load disc to rotate synchronously, when the driving motor starts to rotate at an accelerated speed from a uniform speed Vv, the load disc loads a positive torque to a test piece, and the load disc is driven to rotate synchronously; the driving motor stops accelerating until the speed of the driving motor reaches the maximum speed Vmax required by the test; when the driving motor starts to decelerate and rotate, the load disc loads a negative torque to the test piece until the speed of the driving motor is reduced to the minimum speed Vmin required by the test, namely, the complete cycle loading of the alternating torque is completed; and the loading test is repeated, so that the total number of loading times of the alternating torque meets the test requirement. The loading test method is simple, convenient, high in test efficiency and accurate, meanwhile, the rotating speed conversion time of the driving motor is prolonged, the requirement for synchronous execution of the driving motor is reduced, the service life of the driving motor is longer, and the technical problems encountered by a long-period alternating torque loading test are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical testing, and in particular relates to a test device and a loading test method for shaft torque loading test. Background Art

[0002] In recent years, people have paid more and more attention to the reliability and safety of connection components and equipment. For mature mechanical components, in order to ensure safer and more reliable operation, accelerated life tests of connection components are also carried out to verify the safety and reliability of the connection parts.

[0003] Reliability testing is used to simulate the operating conditions of physical products throughout their entire life cycle. Since it is impossible to truly restore the operating conditions, accelerated testing methods are often used to replace several years or even decades of operating conditions of physical products with a shorter test time, analyze the product's performance, and serve as a supplementary basis for the safe and reliable operation of subsequent products.

[0004] In the reliability test of the connection performance of shaft parts, for the shaft torque loading test requiring more than one million times, it is found that the following problems often exist:

[0005] 1) During the loading test, the repeated loading times are too many, and the test piece rotates to produce large vibrations, which makes the performance of the test equipment unable to meet the test of the entire test cycle.

[0006] 2) In order to truly simulate the current status of the connected components, the parts should be able to freely expand and contract axially during rotation, which cannot be guaranteed by conventional testing organizations.

[0007] 3) The existing test equipment has poor adaptability to different types of test pieces (with large changes in diameter and length), and often needs to be redesigned to meet the requirements, which is costly.

[0008] At the same time, in torque loading and torque testing, the stability, timely response and continuity of motor output are obviously superior to other drive methods. In various laboratory tests, motor drive becomes the first choice, but in the long-cycle alternating torque loading (loading times of more than one million times) test project, the following problems are found in the test and inspection of shaft components:

[0009] 1) Alternating torque loading is generally performed by means of forward and reverse rotation of the motor. For tests requiring a large number of alternating times, frequent forward and reverse rotations will seriously damage the performance and life of the motor, making it difficult for the motor to complete a test cycle.

[0010] 2) For massive and disordered loading test data, invalid loading times must be eliminated, and it is very difficult to screen out valid and qualified loading times.

[0011] 3) Product parameters are different, and dedicated personnel are required to continuously adjust and load new loading parameters to meet the test requirements, resulting in low test efficiency. Summary of the invention

[0012] The purpose of the present invention is to solve the above technical problems and provide a loading test method which has a reasonable structure, is safe and reliable, and has high test efficiency and is accurate.

[0013] To achieve the above-mentioned purpose, the present invention provides a test device for shaft torque loading test, which includes, from left to right, a drive motor, a reduction gearbox connected to the output shaft of the drive motor, a left coupling, a left clamping device, a right clamping device, a right first coupling and a load plate, wherein the output shaft of the reduction gearbox is connected to one end of the left coupling, and one end of the left clamping device passes through the left bearing seat and is connected to the other end of the left coupling; it also includes a sensor and a right second coupling, wherein one end of the right clamping device passes through the right bearing seat and is connected to one end of the right first coupling, one end of the sensor is connected to the other end of the right first coupling, the other end of the sensor is connected to one end of the right second coupling, and the output shaft of the load plate is connected to the other end of the right second coupling.

[0014] Furthermore, the structures of the left coupling, the first right coupling and the second right coupling are the same, and axial openings are opened on the outer circular walls of the connecting holes at both ends of the coupling, and radial connecting bolt holes for bolts to pass through are opened around the axial opening positions on the outer circular walls of the connecting holes at both ends.

[0015] Furthermore, the inner diameters of the connecting holes at both ends of the coupling are slightly larger than the outer diameters of the shafts connected to the connecting holes.

[0016] Furthermore, the left clamping device and the right clamping device have the same structure, both of which include a semi-connecting shaft and a chuck seat mounted on the semi-connecting shaft, the chuck seat being evenly provided with a plurality of claws along the circumference, the claws being connected with a fixed clamping ring via a connecting fixing block, and the end of the fixed clamping ring being mounted on the end of the specimen; a fixed limit block and a guide block located between the fixed limit block and the chuck seat are mounted on the semi-connecting shaft, and a keyway is used between the guide block and the semi-connecting shaft; the semi-connecting shaft of the left clamping device passes through the left bearing seat and is connected to the other end of the left coupling, and the semi-connecting shaft of the right clamping device passes through the right bearing seat and is connected to one end of the right coupling.

[0017] Furthermore, the width of the guide block is greater than the width of the key slot, so that there is a gap between the key slot and the fixed limit blocks and the chuck seat on both sides, and an elastic member is installed in the gap.

[0018] Furthermore, the front and rear end surfaces of the guide block are respectively positioned with the fixed limit block and the chuck seat through stoppers.

[0019] Furthermore, the fixing clamp is a Hough structure, which is composed of an upper Hough ring and a lower Hough ring connected by bolts; a plurality of fixing clamp concave stops are evenly arranged along the circumference of the fixing clamp, and a connecting fixing block convex stop is provided at the lower end of the connecting fixing block which is plugged into the fixing clamp concave stop corresponding to the fixing clamp concave stop.

[0020] Furthermore, a connection fixing block concave stopper corresponding to the clamping claw is provided on one side of the connection fixing block.

[0021] Furthermore, it also includes a driving section mounting seat, a load section mounting seat and a platform, the reduction box and the left bearing seat are arranged on the driving section mounting seat, the load plate and the right bearing seat are arranged on the load section mounting seat, and the driving section mounting seat and the load section mounting seat are arranged on the platform.

[0022] A loading test method for the test device as described above is also provided, wherein the driving motor rotates forward to drive the load plate to rotate synchronously, and when the driving motor starts to accelerate from the average speed Vv, the load plate loads a positive torque on the test piece until the speed of the driving motor reaches the maximum speed V required by the test. max , the drive motor stops accelerating; when the drive motor starts to decelerate, the load plate applies negative torque to the test piece until the speed of the drive motor decreases to the minimum speed V required by the test. min , that is, complete a complete cycle of alternating torque loading; repeat the loading test so that the total number of alternating torque loading times meets the test requirements and complete the reliability test.

[0023] Furthermore, when the load plate applies positive torque to the test piece, the sensor collects the positive torque loading value in real time, and the driving motor accelerates at an acceleration time T + When the positive torque loading value is collected and is greater than or equal to the positive torque threshold M for the first time, + When the loading torque is judged to be qualified, the loading torque qualified count is increased by one, the loading times count is increased by one, and the subsequent collected positive torque loading value is no longer equal to the positive torque threshold M + Make a judgment; when the driving motor is in acceleration time T + Within the range, all collected positive torque loading values ​​are less than the positive torque threshold M + When the loading torque is judged as unqualified, the loading torque is not counted if it is qualified, but the loading times count is increased by one;

[0024] Similarly, the load plate applies negative torque to the test piece, and the sensor collects the negative torque loading value in real time, and the drive motor is decelerated at the time T - When the negative torque load value is collected for the first time and is less than or equal to the negative torque threshold M - When the loading torque is judged to be qualified, the loading torque qualified count is increased by one, the loading times count is increased by one, and the negative torque loading value collected subsequently is no longer equal to the negative torque threshold M -Make a judgment; when the drive motor is in the deceleration time T - All collected negative torque loading values ​​are greater than the negative torque threshold M - When the loading torque is judged to be unqualified, the loading torque is not counted if it is qualified, but the loading times count is increased by one.

[0025] Furthermore, when the number of qualified loading torque times divided by the total loading times of the drive motor within the specified time period T is greater than or equal to 95%, the drive motor meets the torque requirement; if the number of qualified loading torque times divided by the total loading times is less than 95%, the drive motor does not meet the torque requirement, and the positive acceleration β of the drive motor is optimized. +、 Negative acceleration β - , redetermine the acceleration time T +、 Deceleration time T - , and then re-carry out the loading test;

[0026] Furthermore, the specific method for optimizing the loading parameters of the drive motor is:

[0027] When loading positive torque, when the number of qualified loading torque divided by the total number of loading is less than 50%, the positive acceleration β of the drive motor + Increase by 8-10%; when the number of qualified loading torque divided by the total number of loading is 50-70%, the positive acceleration β of the drive motor + Increase by 6-7%; when the number of qualified loading torque divided by the total number of loading is 70-90%, the positive acceleration β of the drive motor + Increase by 4-5%; when the number of qualified loading torque divided by the total number of loading is 90-95%, the positive acceleration β of the drive motor + Increase by 2-3%;

[0028] Similarly, when negative torque is loaded, when the number of qualified loading torque divided by the total number of loading times is less than 50%, the negative acceleration β of the drive motor - Increase by 8-10%; when the number of qualified loading torque divided by the total number of loading is 50-70%, the negative acceleration β of the drive motor - Increase by 6-7%; when the number of qualified loading torque divided by the total number of loading is 70-90%, the negative acceleration β of the drive motor - Increase by 4-5%; when the number of qualified loading torque divided by the total number of loading is 90-95%, the negative acceleration β of the drive motor - Increase by 2-3%.

[0029] Furthermore, the acceleration time T + The calculation process is as follows:

[0030]

[0031] Deceleration time T - The calculation process is as follows:

[0032]

[0033] Among them, V max is the maximum speed, V min is the minimum speed and Vv is the average speed.

[0034] In view of the problems existing in the background technology, the inventor has made the following improvements:

[0035] 1) Axial openings are provided on the outer circumferential walls of the connecting holes at both ends of the coupling, and radial connecting bolt holes for bolts to pass through are provided around the axial opening positions on the outer circumferential walls of the connecting holes at both ends of the coupling; at the same time, the inner diameter of the connecting holes at both ends of the coupling is slightly larger than the outer diameter of the shaft connected to the connecting holes; compared with the conventional keyway installation, in this embodiment, since the inner diameter of the connecting hole is slightly larger than the shaft, and there is no need to consider the orientation and repair installation of the keyway and the key, the installation is convenient, the installation difficulty is reduced, and the installation efficiency can be improved by more than 50%. At the same time, due to the surface contact, the torque transmission capacity is strong.

[0036] 2) The axis of the test piece is telescopically transferred to the clamping devices at both ends. The clamping devices are connected and clamped with the test piece. The clamping devices can be axially telescopic with the test piece and slide along the clamping devices without affecting the rotation of the test piece.

[0037] 3) The test piece is located between two clamping devices. The test piece has a large deadweight and will vibrate and shake during high-speed rotation, affecting the stability of the entire test device. Therefore, in order to reduce the impact of the deadweight of the test piece on the test, the drive motor is installed on the side end face of the reduction box, and the load plate is installed at the end of the axis of the test device. The deadweight of the drive motor and the load plate offsets the weight of the balanced test piece, which can effectively improve the stress conditions of the left coupling, bearing seat, right first coupling and right second coupling in this practical device. At the same time, when the loading device rotates, the load plate can make the test device run smoothly, reduce shaking and vibration, and greatly improve the service life of each test component.

[0038] 4) The sensor is connected in series to the rear end of the test piece and rotates synchronously with the test piece. When changing to a different model of test piece, since the sensor is not directly connected to the test piece, as long as the dynamic torque meter (sensor) test range is appropriate, there is no need to disassemble or replace the sensor, which improves measurement efficiency and reduces measurement deviation.

[0039] 5) The clamping device is designed with a fixed clamping ring, which is put on the thin-walled part. The clamping force of the claw is dispersed through the fixed clamping ring to form a uniform annular tightening force, which strengthens the local strength of the thin-walled test piece and can withstand a larger clamping force of the claw, further increasing the friction between the fixed clamping ring and the thin-walled test piece to prevent the clamping part from loosening and slipping during the test, while also avoiding the problem of local deformation of the thin-walled part caused by excessive local locking force due to direct clamping of the claw; the fixed clamping ring is preferably a Huff structure, and the upper and lower Huff rings can be locked with bolts. The claw is connected to the fixed block and connected to the fixed clamping ring through a stopper, which is convenient for disassembly and positioning, thereby improving the test efficiency.

[0040] 6) A keyway matching the semi-connected shaft is provided on the guide block of the clamping device. When the semi-connected shaft is driven to rotate by external force, the torque is transmitted through the keyway, causing the guide block to rotate synchronously. When the speed of the semi-connected shaft changes or rotates in the opposite direction, the keyway connection can perfectly adapt to the torque change and transmit it synchronously. When the guide block rotates, it can slide on the keyway of the semi-connected shaft, flexibly adapting to the free expansion and contraction of the axial direction of the test piece during the rotation process under alternating loading conditions.

[0041] 7) The front and rear end surfaces of the guide block of the clamping device are positioned with the fixed limit block and the chuck seat through the stoppers respectively. The three are fixed as a whole and can rotate and slide freely with the guide block. Since the width of the guide block is greater than the width of the keyway, there is a gap between the keyway and the fixed limit blocks and the chuck seat on both sides. The existence of the gap not only meets the space requirement for the guide block to slide on the keyway, but also cleverly limits the sliding distance of the guide block in both directions to prevent the guide block from escaping from the semi-connecting shaft. Furthermore, an elastic member is installed in the gap, and when the force causing the guide block to shift disappears, it can be reset under the action of the elastic member.

[0042] 8) The positive and negative torque of the present invention is generated by the load disk at maximum acceleration and maximum deceleration, thereby overcoming the problem of motor life damage caused by frequent positive and reverse rotation during motor torque testing.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1) The invention has a simple structure, is safe and reliable, and is easy to disassemble and assemble. At the same time, the clamping device has a large adjustable range, and the load section can be moved over a long distance by adjusting the mounting seat, which can adapt to test pieces of different diameters and lengths for loading tests. It solves the problems of insufficient performance of ultra-high frequency test equipment, free expansion and contraction of the test piece in the axial direction during rotation, and small adaptability of the test device. The loading device of the invention has been verified by our company's long-term experiments, and has a reasonable structure, safety and reliability, and convenient disassembly and assembly of the test piece, which meets the requirements of torque loading tests of multiple types of shafts;

[0045] 2) In the present invention, since the sensor is not directly connected to the test piece, as long as the dynamic torque measurement range is appropriate, there is no need to disassemble or replace the dynamic sensor, thereby improving measurement efficiency and reducing measurement deviation;

[0046] 3) The clamping device of the present invention solves the problems of free expansion and contraction of the axis direction of the test piece during rotation under alternating loading conditions, easy deformation of the thin wall thickness of the test piece, and easy loosening and slipping of the clamping claws. The clamping device has a simple structure, reliable performance, and a wide range of applications;

[0047] 4) The loading test method of the present invention is simple, efficient and accurate. At the same time, the speed change time of the drive motor is prolonged, the requirement for synchronous execution of the drive motor is reduced, the service life of the drive motor is longer, and the technical problems encountered in long-cycle alternating torque loading tests are solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic diagram of the structure of the test device for shaft torque loading test of the present invention;

[0049] Figure 2 for Figure 1 Schematic diagram of the structure of the middle clamping device;

[0050] Figure 3 for Figure 2 Schematic diagram of the structure of the middle fixed clamp ring;

[0051] Figure 4 for Figure 2 AA partial schematic diagram;

[0052] Figure 5 for Figure 2 Partial schematic diagram of the middle BB;

[0053] Figure 6 for Figure 2 Main view of the middle connection positioning block;

[0054] Figure 7 for Figure 2 Usage status diagram;

[0055] Figure 8 for Figure 1 Partial schematic diagram of the middle coupling;

[0056] Fig. 9 It is a schematic diagram of a loading control curve of the loading test method of the present invention;

[0057] Fig.10 It is a real-time collection torque signal diagram of the loading test method of the present invention;

[0058] Fig.11 is a qualified counting judgment diagram;

[0059] Fig.12 This is a table showing the test pass rate.

[0060] Among them, a-left clamping device, b-right clamping device, 1-semi-connecting shaft, 2-fixed limit block, 3-guide block, 4-chuck seat, 5-claw, 5-1-claw convex stop, 6-connection fixing block, 6-1-fixing screw hole, 6-2-connection fixing block concave stop, 6-3-connection fixing block convex stop, 7-test piece, 8-fixed snap ring, 8-1-upper half ring, 8-2-lower half ring, 8-3-fixed snap ring concave stop, 9 -elastic part, 10-keyway, 11-gap, 12-drive motor, 13-drive section mounting seat, 14-reduction box, 15-left coupling, 16-left bearing seat, 17-right first coupling, 18-sensor, 19-right second coupling, 20-load plate, 21-load section mounting seat, 22-adjustment mounting seat, 23-platform, 24-right bearing seat, 25-axial opening, 26-connection hole, 27-radial connection bolt hole. DETAILED DESCRIPTION

[0061] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0062] like Figure 1 The test device for shaft torque loading test shown in the figure includes, from left to right, a drive motor 12, a reduction box 14 connected to the output shaft of the drive motor 12, a left coupling 15, a left bearing seat 16, a left clamping device a, a right clamping device b, a right bearing seat 24, a right first coupling 17, a sensor 18, a right second coupling 19 and a load plate 20; it also includes a drive section mounting seat 13, a load section mounting seat 21, an adjustment mounting seat 22 and a platform 23, the reduction box 14 and the left bearing seat 16 are arranged on the drive section mounting seat 13, the load plate 20 and the right bearing seat 24 are arranged on the load section mounting seat 21, the load section mounting seat 21 is arranged on the adjustment mounting seat 22, and the drive section mounting seat 13 and the adjustment mounting seat 22 are arranged on the platform 23.

[0063] In this embodiment, the left clamping device a and the right clamping device b have the same structure, see Figure 2 , including a semi-connecting shaft 1, and a fixed limit block 2, a guide block 3 and a chuck seat 4 which are sequentially mounted on the semi-connecting shaft 1. The chuck seat 4 is evenly provided with a plurality of claws 5 along the circumferential direction (three in this embodiment, and the telescopic position of the claws 5 is adjustable, for example, the synchronous movement of a plurality of claws 5 can be achieved through a gear transmission mechanism, which is suitable for products of different specifications), and the claws 5 are connected to the fixed clamping ring 8 through the connecting fixed block 6.

[0064] The output shaft of the reduction box 14 is connected to one end of the left coupling 15, the half connecting shaft 1 of the left clamping device a passes through the left bearing seat 16 and is connected to the other end of the left coupling 15; the half connecting shaft 1 of the right clamping device b passes through the right bearing seat 24 and is connected to one end of the right first coupling 17, one end of the sensor 18 is connected to the other end of the right first coupling 17, the other end of the sensor 18 is connected to one end of the right second coupling 19, and the output shaft of the load plate 20 is connected to the other end of the right second coupling 19. The shaft system of the test piece 7 is telescopically transferred to the clamping devices at both ends, and the clamping devices are connected and clamped with the test piece 7. The clamping devices can be axially telescopic with the test piece 7 and slide along the clamping devices without affecting the rotation of the test piece.

[0065] The sensor 18 is connected in series to the rear end of the test piece 7 and rotates synchronously with the test piece 7. When replacing a different type of test piece 7, since the sensor 18 is not directly connected to the test piece 7, as long as the dynamic torque measurement range is appropriate, there is no need to disassemble and replace the dynamic sensor 18, thereby improving measurement efficiency and reducing measurement deviation.

[0066] The test piece 7 is located between the two clamping devices. The test piece 7 has a large deadweight and will generate vibration and jitter during high-speed rotation, affecting the stability of the entire test device. Therefore, in order to reduce the impact of the deadweight of the test piece 7 on the test, the drive motor 12 is installed on the side end face of the reduction box 14, and a heavy load disk 20 is provided. The load disk 20 is installed at the end of the axis of the test device, so that the deadweight of the drive motor 12 and the load disk 20 offsets the weight of the balanced test piece 7. This can effectively improve the stress conditions of the left coupling, bearing seat, right first coupling and right second coupling in the practical device. At the same time, when the loading device rotates, the load disk can make the test device run smoothly, reduce jitter and vibration, and greatly improve the service life of each test component.

[0067] In addition, if Figure 8 As shown, the structures of the left coupling 15, the first right coupling 17 and the second right coupling 19 are the same. The outer circumferential walls of the connecting holes 26 at both ends of the coupling are provided with axial openings 25, and radial connecting bolt holes 27 for bolts to pass through are provided around the outer circumferential walls of the connecting holes 26 at both ends at the positions of the axial openings 25; at the same time, the inner diameter of the connecting holes 26 at both ends of the coupling is slightly larger than the outer diameter of the shaft connected to the connecting holes. That is, the output shaft of the reduction box is inserted into the connecting hole at one end of the left coupling, and is locked by bolts to reduce the axial opening, drive the connecting hole to shrink, and thus firmly fix the left coupling on the output shaft of the reduction box; compared with the conventional keyway installation, in this embodiment, since the inner diameter of the connecting hole is slightly larger than the shaft, and there is no need to consider the orientation and repair installation of the keyway and the key, the installation is convenient, the installation difficulty is reduced, and the installation efficiency can be increased by more than 50%. At the same time, since it is surface contact, the torque transmission capacity is strong. The installation principle of other connecting holes and shafts is the same, which will not be repeated here.

[0068] In this embodiment, the adjusting mounting seat 22 can use a screw drive to drive the load segment mounting seat to move axially (i.e., left and right), which is practical for testing test pieces 7 of different lengths and reduces the number of devices used. The adjusting mounting seat is a conventional structure, and any mechanical drive, gear drive, electric push rod drive, etc. that can achieve axial movement can be used.

[0069] Also, see Figure 4 The guide block 3 and the semi-connected shaft 1 are matched with a keyway 10. When the semi-connected shaft 1 is driven to rotate by an external force, the torque is transmitted through the keyway to make the guide block 3 rotate synchronously. In the axial direction, the width of the guide block 3 is greater than the width of the keyway 10, so that there is a gap 11 between the keyway 10 and the fixed limit blocks 2 and the chuck seat 4 on both sides, and the gap 11 is equipped with an elastic member 9. Alternatively, the front and rear end surfaces of the guide block 3 are respectively positioned with the fixed limit block 2 and the chuck seat 4 through stoppers, and are fixedly connected by bolts, and can rotate or move axially with the guide block 3.

[0070] See also Figure 3 The fixed snap ring 8 can be a half structure, consisting of an upper half ring 8-1 and a lower half ring 8-2 connected by bolts. A plurality of fixed snap ring concave stops 8-3 (the specific number corresponds to the claw 5) are evenly arranged along the circumference of the fixed snap ring 8. Figure 6 The lower end of the connecting and fixing block 6 is provided with a connecting and fixing block convex stop 6-3 corresponding to the fixing clamp ring concave stop 8-3, and one side of the connecting and fixing block 6 is provided with a connecting and fixing block concave stop 6-2 corresponding to the claw 5, and the two are also connected by bolts. When the rotation direction or speed changes, the torque can be reliably transmitted through the stop connection.

[0071] Combination Figure 7 As shown, the installation and testing of the device of the present invention,

[0072] (1) Installation of fixed snap ring

[0073] The test piece 7 is hoisted in the air, the upper half ring 8-1 and the lower half ring 8-2 of the fixed snap ring 8 are connected into a whole ring with connecting bolts, the fixed snap ring 8 is put on the outer circle of the end face of the test piece 7, the connecting bolts on the fixed snap ring 8 are locked, and the fixed snap ring 8 is fixed to one end of the test piece 7.

[0074] (2) Assemble the clamping device

[0075] The guide block 3 is inserted into the detection part of the semi-connected shaft 1, and the elastic member 9 is installed in the groove of the guide block 3 and the semi-connected shaft 1. The fixed limit block 2 and the chuck seat 4 are respectively installed at both ends of the guide block 3 and fixed as a whole with connecting bolts. The claw 5 is installed on the chuck seat 4, and the clamping range of the claw 5 is adjusted to the required size through the transmission mechanism (such as gear transmission).

[0076] (3) Test piece installation

[0077] Lift the test piece 7 together with the fixed snap ring 8 onto the clamping device, adjust the claw 5 to align with the fixed snap ring concave stop 8-3 of the fixed snap ring 8, push the connection positioning block 6 horizontally from the fixed snap ring concave stop 8-3, ensure that the end face of the connection positioning block 6 convex stop 6-3 is attached to the end face of the fixed snap ring concave stop and the concave stop of the connection positioning block 6 is clamped into the claw convex stop 5-1 of the claw 5 (such as Figure 5 As shown), fix the connection fixing block 6 to the claw 5 with bolts to complete the installation.

[0078] (4) Installation of other components

[0079] The half connecting shaft 1 of the left clamping device a passes through the left bearing seat 16 and is connected to one end of the left coupling 15, and the other end of the left coupling 15 is connected to the driving motor 12 through the reducer 14; the half connecting shaft 1 of the right clamping device b passes through the right bearing seat 24 and is connected to one end of the right first coupling 17, and the other end of the right first coupling 17 is connected to one end of the sensor 18, and the other end of the sensor 18 is connected to the load disk 20 through the right second coupling 19.

[0080] When the speed of the semi-connected shaft 1 changes or rotates in the opposite direction, the keyway 10 connection can perfectly adapt to the torque change and synchronously transmit it to the guide block 3. When the guide block 3 rotates, the loading torque is transmitted to the test piece 7 through the claw 5, the connection positioning block 6, and the fixed snap ring 8, so that the test piece 7 rotates or reverses synchronously.

[0081] During the rotation process, when the test piece 7 is stretched or shortened due to flexural deformation or other reasons such as high rotation speed, the axial expansion and contraction force is transmitted to the connection positioning block 6 and the claw 5 through the fixed clamp ring 8, and finally fed back to the guide block 3. Due to the existence of the gap 11, the guide block 3 can be displaced axially along the keyway of the semi-connected shaft 1. When the test piece 7 runs smoothly, the deformation disappears, and the guide block 3 returns to normal under the action of the elastic member 9 and the axial force. The thin-walled test piece 7 can be freely expanded and contracted axially during the test, which can simulate the actual use conditions.

[0082] The contact surface between the fixed snap ring 8 and the test piece 7 is much larger than the direct clamping method of the claw 5. This not only disperses the clamping force of the claw 5 to prevent the test piece 7 from deformation, but also the fixed snap ring strengthens the local strength of the test piece 7 and can withstand a larger clamping force of the claw 5, further increasing the friction between the fixed snap ring 8 and the test piece 7 to prevent the clamping part from loosening or slipping during the test.

[0083] The test piece 7 is clamped by the left clamping device a and the right clamping device b. The claws 5 on the clamping device can adapt to the clamping of test pieces 7 with different diameters, and at the same time, the test piece 7 and the loaded test device are at the same rotation center, reducing system deviation during the test.

[0084] After the test piece 7 is installed on the test device, the test piece is determined to be qualified by turning the wheel, and the drive motor is started. The motor torque is amplified by the reduction box, and the added torque is transmitted to the half-connection shaft 1 of the left clamping device a, the claw 5 of the left clamping device, the test piece 7, the claw 5 of the right clamping device b, the first right coupling 17, the sensor 18, the second right coupling 19, and the load plate 20 through the left coupling 15. The load plate 20 has a large moment of inertia and cooperates with the drive motor to load the test torque on both ends of the test piece. The sensor rotates synchronously with the test piece 7 and records in real time to feedback the loading torque data on the test piece 7. The torque loading must be repeated continuously to achieve the required number of test loading times and complete up to millions or even tens of millions of loading tests.

[0085] The invention has a simple structure, is safe and reliable, and is easy to assemble and disassemble. At the same time, the clamping device has a large adjustable range, and the load section can be moved over a long distance by adjusting the mounting seat, and can adapt to test pieces of different diameters and lengths for loading tests. It solves the problems of insufficient performance of ultra-high frequency loading test equipment, free expansion and contraction of the test piece in the axial direction during rotation, and a small adaptability range of the test device. The loading device of the invention has been verified by our company's long-term experiments, and has a reasonable structure, safety and reliability, and convenient disassembly and assembly of the test piece, which meets the requirements of multi-model shaft torque loading tests. The clamping device of the invention solves the problems of free expansion and contraction of the test piece in the axial direction during rotation under alternating loading conditions, thin wall thickness of the test piece, and easy deformation, and easy loosening and slipping of the clamping claw. The clamping device has a simple structure, reliable performance, and a wide range of applications.

[0086] Combination Fig. 9 , 10 In the loading test method of the test device shown above, the driving motor 1 rotates forward to drive the load plate 4 to rotate synchronously. When the driving motor 1 starts to accelerate from the average speed Vv, the load plate 4 loads a positive torque on the test piece 2 until the speed of the driving motor reaches the maximum speed V required by the test. max , the driving motor 1 stops accelerating; when the driving motor 1 starts to decelerate, the load plate 4 applies a negative torque to the test piece 2 until the speed of the driving motor is reduced to the minimum speed V required by the test. min , that is, complete a full cycle of alternating torque loading; repeat the loading test so that the total number of alternating torque loading times meets the test requirements.

[0087] Combination Fig.11 When the load plate 4 applies positive torque to the test piece 2, the sensor 3 collects the positive torque loading value in real time, and the driving motor is accelerated at the acceleration time T +When the positive torque loading value is collected and is greater than or equal to the positive torque threshold M for the first time, + When the loading torque is judged to be qualified, the loading torque qualified count is increased by one, the loading times count is increased by one, and the subsequent collected positive torque loading value is no longer equal to the positive torque threshold M + Make a judgment; when the driving motor is in acceleration time T + Within the range, all collected positive torque loading values ​​are less than the positive torque threshold M + When the loading torque is judged as unqualified, the loading torque is not counted if it is qualified, but the loading times count is increased by one;

[0088] Similarly, the load plate 4 applies negative torque to the test piece 2, and the sensor 3 collects the negative torque loading value in real time. The driving motor is at the deceleration time T - When the negative torque load value is collected for the first time and is less than or equal to the negative torque threshold M - When the loading torque is judged to be qualified, the loading torque qualified count is increased by one, the loading times count is increased by one, and the negative torque loading value collected subsequently is no longer equal to the negative torque threshold M - Make a judgment; when the drive motor is in the deceleration time T - All collected negative torque loading values ​​are greater than the negative torque threshold M - When the loading torque is judged to be unqualified, the loading torque is not counted if it is qualified, but the loading times count is increased by one.

[0089] When the drive motor is automatically counted within the specified time period T, if the number of qualified loading torque times divided by the total loading times is greater than or equal to 95%, the drive motor meets the torque requirement; if the number of qualified loading torque times divided by the total loading times is less than 95%, the drive motor does not meet the torque requirement, and the positive acceleration β of the drive motor is optimized. + , redetermine the acceleration time T + , and then re-load the test; when the qualified number of loading torque divided by the total number of loading times is less than 50%, the positive acceleration β of the drive motor + Increase by 8-10%; when the number of qualified loading torque divided by the total number of loading is 50-70%, the positive acceleration β of the drive motor + Increase by 6-7%; when the number of qualified loading torque divided by the total number of loading is 70-90%, the positive acceleration β of the drive motor + Increase by 4-5%; when the number of qualified loading torque divided by the total number of loading is 90-95%, the positive acceleration β of the drive motor + Increase by 2-3%. Fig.12 shown.

[0090] Similarly, when the driving motor is automatically counted within the specified time period T, if the qualified loading torque divided by the total number of loading times is greater than or equal to 95%, the driving motor meets the torque requirement; if the qualified loading torque divided by the total number of loading times is less than 95%, the driving motor does not meet the torque requirement, and the negative acceleration β of the driving motor is optimized. - , redetermine the deceleration time T - , and then re-load the test; when the qualified number of loading torque divided by the total number of loading times is less than 50%, the negative acceleration β of the drive motor - Increase by 8-10%; when the number of qualified loading torque divided by the total number of loading is 50-70%, the negative acceleration β of the drive motor - Increase by 6-7%; when the number of qualified loading torque divided by the total number of loading is 70-90%, the negative acceleration β of the drive motor - Increase by 4-5%; when the number of qualified loading torque divided by the total number of loading is 90-95%, the negative acceleration β of the drive motor - Increase by 2-3%.

[0091] The above acceleration time T + The calculation process is as follows:

[0092]

[0093] Deceleration time T - The calculation process is as follows:

[0094]

[0095] Among them, V max is the maximum speed, V min is the minimum speed and Vv is the average speed.

[0096] The torque loading method of the present invention overcomes the problem of motor life damage caused by frequent forward and reverse rotation during motor torque testing; the present invention makes certain improvements on the existing motor alternating torque loading test method, and finally forms a reasonable, feasible and efficient alternating torque loading test method. After long-term experimental verification by our company, this method can be well applied to alternating torque loading test monitoring, and the comparison confirms that the recorded data is complete and reliable, has certain practicality, and can be used in similar tests.

Claims

1. A test device for shaft torque loading test, which comprises, from left to right, a driving motor, a reduction box connected to the output shaft of the driving motor, a left coupling, a left clamping device, a right clamping device, a right coupling and a load plate, wherein the output shaft of the reduction box is connected to one end of the left coupling, and one end of the left clamping device passes through the left bearing seat and is connected to the other end of the left coupling; characterized in that: It also includes a sensor and a right second coupling. One end of the right clamping device passes through the right bearing seat and is connected to one end of the right first coupling. One end of the sensor is connected to the other end of the right first coupling. The other end of the sensor is connected to one end of the right second coupling. The output shaft of the load plate is connected to the other end of the right second coupling.

2. The test device for shaft torque loading test according to claim 1, characterized in that: The structures of the left coupling, the first right coupling and the second right coupling are the same. Axial openings are opened on the outer circular walls of the connecting holes at both ends of the coupling, and radial connecting bolt holes for bolts to pass through are opened around the axial opening positions on the outer circular walls of the connecting holes at both ends. The inner diameters of the connecting holes at both ends of the coupling are slightly larger than the outer diameters of the shafts connected to the connecting holes.

3. The test device for shaft torque loading test according to claim 1, characterized in that: The left clamping device and the right clamping device have the same structure, both of which include a semi-connecting shaft and a chuck seat mounted on the semi-connecting shaft, the chuck seat being evenly provided with a plurality of claws along the circumference, the claws being connected with the fixed clamping ring through the connecting fixing block, and the end of the fixed clamping ring being mounted on the end of the specimen; the semi-connecting shaft is mounted with a fixed limit block and a guide block located between the fixed limit block and the chuck seat, and a keyway is used between the guide block and the semi-connecting shaft; the semi-connecting shaft of the left clamping device passes through the left bearing seat and is connected to the other end of the left coupling, and the semi-connecting shaft of the right clamping device passes through the right bearing seat and is connected to one end of the right coupling; the width of the guide block is greater than the width of the keyway, so that there is a gap between the keyway and the fixed limit blocks and the chuck seat on both sides, and an elastic member is installed in the gap; the front and rear end faces of the guide block are respectively positioned with the fixed limit block and the chuck seat through stoppers.

4. The test device for shaft torque loading test according to claim 3, characterized in that: The fixed clamping ring is a Hough structure, which is composed of an upper Hough ring and a lower Hough ring connected by bolts; a plurality of fixed clamping ring concave stops are evenly arranged along the circumference of the fixed clamping ring, and a connecting and fixing block convex stop is provided at the lower end of the connecting and fixing block corresponding to the fixing clamping ring concave stop; a connecting and fixing block concave stop is provided on one side of the connecting and fixing block corresponding to the claw.

5. The test device for shaft torque loading test according to claim 1, characterized in that: It also includes a driving section mounting seat, a load section mounting seat and a platform, the reduction box and the left bearing seat are arranged on the driving section mounting seat, the load plate and the right bearing seat are arranged on the load section mounting seat, and the driving section mounting seat and the load section mounting seat are arranged on the platform.

6. A loading test method according to any one of claims 1 to 5, characterized in that: The loading test process is as follows: the driving motor rotates forward to drive the load plate to rotate synchronously. When the driving motor starts to accelerate from the average speed Vv, the load plate loads positive torque on the test piece until the speed of the driving motor reaches the maximum speed V required by the test. max , the drive motor stops accelerating; when the drive motor starts to decelerate, the load plate applies negative torque to the test piece until the speed of the drive motor decreases to the minimum speed V required by the test. min , that is, complete a full cycle of alternating torque loading; repeat the loading test so that the total number of alternating torque loading times meets the test requirements.

7. The loading test method of the test device according to claim 6, characterized in that: When the load plate applies positive torque to the test piece, the sensor collects the positive torque loading value in real time, and the driving motor is accelerated at the acceleration time T + When the positive torque loading value is collected and is greater than or equal to the positive torque threshold M for the first time, + When the loading torque is judged to be qualified, the loading torque qualified count is increased by one, the loading times count is increased by one, and the subsequent collected positive torque loading value is no longer equal to the positive torque threshold M + Make a judgment; when the driving motor is in acceleration time T + Within the range, all collected positive torque loading values ​​are less than the positive torque threshold M + When the loading torque is judged as unqualified, the loading torque is not counted if it is qualified, but the loading times count is increased by one; Similarly, the load plate applies negative torque to the test piece, and the sensor collects the negative torque loading value in real time. The drive motor is decelerated at the time T — When the negative torque load value is collected for the first time and is less than or equal to the negative torque threshold M — When the loading torque is judged to be qualified, the loading torque qualified count is increased by one, the loading times count is increased by one, and the negative torque loading value collected subsequently is no longer equal to the negative torque threshold M — Make a judgment; when the drive motor is in the deceleration time T — All collected negative torque loading values ​​are greater than the negative torque threshold M — When the loading torque is judged to be unqualified, the loading torque is not counted if it is qualified, but the loading times count is increased by one.

8. The loading test method of the test device according to claim 7, characterized in that: When the number of qualified loading torque times divided by the total loading times of the drive motor within the specified time period T is greater than or equal to 95%, the drive motor meets the torque requirement; if the number of qualified loading torque times divided by the total loading times is less than 95%, the drive motor does not meet the torque requirement, and the positive acceleration β of the drive motor is optimized. +、 Negative acceleration β — , redetermine the acceleration time T +、 Deceleration time T — , and then repeat the loading test.

9. The loading test method of the test device according to claim 8, characterized in that: The specific method for optimizing the loading parameters of the drive motor is: When loading positive torque, when the number of qualified loading torque divided by the total number of loading is less than 50%, the positive acceleration β of the drive motor + Increase by 8-10%; when the number of qualified loading torque divided by the total number of loading is 50-70%, the positive acceleration β of the drive motor + Increase by 6-7%; when the number of qualified loading torque divided by the total number of loading is 70-90%, the positive acceleration β of the drive motor + Increase by 4-5%; when the number of qualified loading torque divided by the total number of loading is 90-95%, the positive acceleration β of the drive motor + Increase by 2-3%; Similarly, when negative torque is loaded, when the number of qualified loading torque divided by the total number of loading times is less than 50%, the negative acceleration β of the drive motor — Increase by 10%; when the number of qualified loading torque divided by the total number of loading is 50-70%, the negative acceleration β of the drive motor — Increase by 6-7%; when the number of qualified loading torque divided by the total number of loading is 70-90%, the negative acceleration β of the drive motor — Increase by 4-5%; when the number of qualified loading torque divided by the total number of loading is 90-95%, the negative acceleration β of the drive motor — Increase by 2-3%.

10. The loading test method of the test device according to claim 7, characterized in that: The acceleration time T + The calculation process is as follows: Deceleration time T — The calculation process is as follows: Among them, V max is the maximum speed, V min is the minimum speed and Vv is the average speed.

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