A device for testing the dynamic balance of an automobile transmission shaft

Abstract

The application relates to the technical field of dynamic balance testing of transmission shafts, in particular to a dynamic balance testing device for automobile transmission shafts, which comprises a bottom plate and a linear driving device arranged on the bottom plate, a driving component and a driven component capable of moving relative to or away from each other are arranged on the linear driving device, and the driving component is used for clamping and driving the universal joint at one end of the automobile transmission shaft to be tested. Two fixed rings corresponding to the universal joint rotation reference and the outer periphery of the shaft body are arranged in the coaxial detection component, a plurality of radial detection structures with contact wheels and telescopic detection elements are arranged in each fixed ring, the shaft body can be distinguished from the rotation axis of the driving end according to the displacement distribution when rotating at a low speed before dynamic balance testing, whether the angle deflection of the shaft body relative to the driving end rotation axis is a fixed direction or a cyclical change of conical swing, so that additional vibration caused by clamping different shafts is avoided from being misjudged as the imbalance of the transmission shaft itself.

Description

Technical Field

[0001] This invention relates to the field of dynamic balancing testing technology for drive shafts, and more specifically to a dynamic balancing testing device for automotive drive shafts. Background Technology

[0002] Automotive driveshafts typically consist of a shaft body, universal joints, and end connectors. They are used to transmit torque between different components of a vehicle's transmission system. During operation, the driveshaft rotates at high speed. Factors such as shaft tube machining deviations, end welding eccentricities, universal joint assembly errors, and uneven local mass distribution can all cause radial vibrations when the driveshaft rotates. Therefore, driveshaft assemblies usually need to undergo dynamic balancing tests before being installed in vehicles to determine whether their rotational state meets the usage requirements.

[0003] Existing dynamic balancing testing equipment for drive shafts typically clamps universal joints or end connectors at both ends of the drive shaft. One end drives the drive shaft to rotate, and the other end rotates with the drive shaft. Although the self-centering fixture can initially align the clamped part with the test shaft, the universal joint itself has a certain angular movement capability. After the clamped universal joint is aligned with the test shaft, the shaft body connected to the universal joint may still form a fixed sway angle relative to the test shaft. For example, when there is a deviation in the installation height or horizontal position of the driven end, the shaft body may always tilt upward, downward, or to one side. In this state, the center line of the shaft body does not coincide with the rotation axis of the driving end, and additional vibrations caused by clamping different shafts are easily generated during the test. Summary of the Invention

[0004] To address the aforementioned shortcomings of existing technologies, this invention provides a dynamic balancing testing device for automotive drive shafts, which can effectively solve the problem that the axle body may still have a fixed angle of misalignment after being clamped by a universal joint in existing technologies.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a dynamic balancing testing device for automotive drive shafts, comprising:

[0007] The base plate and the linear drive device disposed on the base plate are provided with an active drive component and a driven drive component that can move relative to or away from each other. The active drive component is used to clamp and drive the universal joint at one end of the test vehicle drive shaft to rotate. The driven drive component is used to clamp the other end of the universal joint and rotate accordingly. The driven drive component is provided with a two-dimensional drive device that drives the clamping position to move up and down and left and right.

[0008] The active drive assembly is provided with a coaxial detection assembly, which includes two fixed rings corresponding to the outer circumference of the universal joint rotation reference and the outer circumference of the adjacent shaft respectively. Each fixed ring is provided with multiple sets of radially retractable contact wheels and telescopic detection elements for detecting their retraction displacement, which are symmetrically arranged along the circumference.

[0009] The displacement distribution of the two fixed rings is used to distinguish between fixed-direction angular deviation and conical oscillation that changes with rotation before dynamic balancing test. The two-dimensional drive device is used to drive the driven component to move in the direction of reducing deviation when there is fixed-direction angular deviation. After the adjustment is completed, the contact wheel is withdrawn and the active drive component drives the test vehicle drive shaft to perform dynamic balancing test.

[0010] Preferably, the active drive assembly includes a first movable plate, a first self-centering chuck, an external frame, and an active linkage shaft. The first movable plate is fixedly installed at the output end of the linear drive device. The first self-centering chuck is rotatably installed on one side of the first movable plate. The external frame is fixedly installed on the other side of the first movable plate. The active linkage shaft is rotatably installed between the external frame and the first movable plate. One end of the active linkage shaft passes through the first movable plate and is fixedly connected to the first self-centering chuck, and the other end is used to connect to the drive source.

[0011] Preferably, the driven component includes a second moving plate, a two-dimensional drive device, and a second self-centering chuck. The second moving plate is fixedly installed on the output end of the linear drive device. The two-dimensional drive device is installed on the second moving plate. The two-dimensional drive device includes a vertical linear drive mechanism and a horizontal linear drive mechanism arranged orthogonally to each other. The second self-centering chuck is rotatably installed on the moving end of the two-dimensional drive device so as to passively rotate with the transmission shaft of the vehicle under test.

[0012] Preferably, slide blocks are fixedly installed on both sides of the first movable plate, and a slide rod is slidably installed in the slide block. A slide groove extending along the length direction is opened in the slide rod, and a slider is slidably installed in the slide groove. The two fixed rings are fixedly connected to the slide rod and the slider respectively, so as to adjust the detection position and spacing of the two fixed rings in the axial direction of the tested vehicle drive shaft.

[0013] Preferably, a plurality of arc-shaped seats are fixedly installed at intervals along the circumference on opposite sides of the fixed ring. An arc-shaped slide bar is slidably installed in the arc-shaped seat. A rotating plate is fixedly installed on one side of the arc-shaped slide bar. A plurality of arc-shaped grooves are spaced apart along the circumference on the rotating plate. A sliding frame is fixedly installed on the fixed ring and located between adjacent arc-shaped seats. A sliding box is slidably installed in the sliding frame. A round rod is fixedly installed on one side of the sliding box. The round rod is slidably disposed in the corresponding arc-shaped groove so that when the rotating plate rotates, it drives each sliding box to move synchronously along the radial direction of the fixed ring.

[0014] Preferably, a connecting box is fixedly installed inside the sliding box, and a block is slidably installed inside the connecting box. The block is fixedly sleeved on the outer wall of the straight rod. The straight rod is arranged radially along the fixing ring. A first spring is sleeved on the outer wall of the straight rod, and the two ends of the first spring are respectively connected to the connecting box and the block. A first connector is fixedly installed at one end of the straight rod facing the axis of the fixing ring. A contact wheel is rotatably installed inside the first connector. The contact wheel is used to make rolling contact with the outer circumference of the universal joint rotation reference or the outer circumference of the shaft.

[0015] Preferably, a T-shaped box is slidably installed inside the sliding box and away from the contact wheel. A screw for adjusting its initial position is threaded inside the T-shaped box. A first short rod is symmetrically fixed inside the T-shaped box. A linkage plate is slidably installed on the first short rod. A second spring is sleeved on the outer wall of the first short rod. The two ends of the second spring are respectively connected to the T-shaped box and the linkage plate. The telescopic detection element is disposed between the T-shaped box and the linkage plate. The end of the straight rod away from the contact wheel passes through the connecting box and the T-shaped box and abuts against the linkage plate.

[0016] Preferably, each of the fixed rings is provided with four sets of radial detection structures formed by the sliding frame and the round rod. The four sets of radial detection structures are arranged at 90-degree intervals along the circumference of the fixed ring and are inclined as a whole relative to the horizontal and vertical directions. Two sets of radial detection structures arranged opposite each other constitute a differential detection group. The detection directions of the two sets of differential detection groups are perpendicular to each other, and the radial detection structures in the two fixed rings adopt the same circumferential installation angle to compare the center offset between the universal joint rotation reference section and the shaft detection section.

[0017] Preferably, it further includes a support assembly, which includes vertical rods slidably mounted on both sides of the linear drive device. A mounting frame is fixedly mounted between the two vertical rods, and a relative drive device is rotatably mounted within the mounting frame. The relative drive device has two threads with opposite directions of rotation, and each thread is connected to a linkage block. A fixing frame is slidably mounted within the linkage block, and multiple bearings are rotatably mounted within the fixing frame. Two belts are closed end-to-end and wrapped around the outer periphery of the corresponding bearings. The two belts are arranged in opposite directions and form a limiting gap for the transmission shaft of the vehicle under test to pass through. An outer connecting pipe is provided on one side of the linkage block. A second short rod is slidably installed inside the outer tube. One end of the second short rod passes through the linkage block and is connected to the fixed frame. The outer tube is equipped with a pressure detection element, a third spring, a magnetorheological fluid, and an electromagnetic device acting on the magnetorheological fluid. A top frame is fixedly installed on the linkage block, a mounting frame is fixedly installed on the top frame, and a lifting drive element is fixedly installed on the mounting frame. A second connector is fixedly installed at the output end of the lifting drive element. A squeezing wheel is rotatably installed inside the second connector. The squeezing wheel is used to squeeze the corresponding belt when the shaft body deflects beyond the limit gap, so as to increase the tension of the belt.

[0018] The technical solution provided by this invention has the following advantages compared with the known prior art:

[0019] First, by setting two fixed rings in the coaxial detection assembly corresponding to the universal joint rotation reference and the outer circumference of the shaft respectively, and arranging multiple sets of radial detection structures with contact wheels and telescopic detection elements at an angle in each fixed ring, it is possible to distinguish whether the shaft has a fixed angular deviation relative to the rotation axis of the active end or a conical oscillation that changes with the rotation cycle when rotating at low speed before dynamic balancing test, based on the displacement distribution. This avoids misjudging the additional vibration caused by clamping different shafts as the imbalance of the transmission shaft itself. For the fixed angular deviation, the two-dimensional drive device drives the driven end clamping position to move in the direction of reducing the deviation, gradually adjusting until the center line of the shaft body tends to coincide with the rotation axis of the active end. Then the contact wheel is removed and the formal test is carried out. This reduces the detection interference caused by the universal joint clamping posture deviation and improves the accuracy of the imbalance test results.

[0020] Secondly, the two belts in the support assembly are arranged in opposite directions and form a limiting gap. During normal testing, they do not contact the shaft, avoiding additional radial constraints. However, when the shaft deflects beyond the gap, the belts are pressed and push the fixing frame and the second short rod. The pressure detection element senses the change in force, and in conjunction with the magnetorheological fluid and electromagnetic device, adjustable damping is generated. At the same time, the lifting drive element drives the squeezing wheel to increase the belt tension. This forms a flexible limit for excessive deflection, preventing the shaft from hitting the equipment or the clamping from becoming unstable. Furthermore, the belts are wound around the bearings and can circulate with the shaft rotation, reducing sliding friction and heat generation. This support structure only intervenes when the deflection exceeds the limit, protecting the equipment without interfering with routine testing, and improving the adaptability and safety of the device for large-sized or initially large-swinging drive shafts. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0022] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of the active drive component of the present invention;

[0024] Figure 3 This is a schematic diagram of the driven component of the present invention;

[0025] Figure 4 This is a schematic diagram of the coaxial detection component of the present invention;

[0026] Figure 5 This is a schematic diagram of the structure of the fixing ring of the present invention;

[0027] Figure 6 This is an exploded structural diagram of the sliding box of the present invention;

[0028] Figure 7 This is a schematic diagram of the internal structure of the connector box of the present invention;

[0029] Figure 8 This is an exploded structural diagram of the support component of the present invention;

[0030] Figure 9 This is an exploded structural diagram of the top frame of the present invention.

[0031] Reference numerals: 1. Base plate; 2. Linear drive device; 3. Active drive assembly; 301. First moving plate; 302. First self-centering chuck; 303. External frame; 304. Active linkage shaft; 4. Driven drive assembly; 401. Second moving plate; 402. Two-dimensional drive device; 403. Second self-centering chuck; 5. Coaxial detection assembly; 501. Slide block; 502. Slide rod; 503. Slider; 504. Fixing ring; 505. Arc-shaped seat; 506. Arc-shaped slide bar; 507. Rotating plate; 508. Arc-shaped groove; 509. Slide frame; 510. Sliding box; 511. Connecting box; 512. T-shaped box; 513. 514. Square block; 515. Straight rod; 516. First connector; 517. Contact wheel; 518. First spring; 519. First short rod; 520. Second spring; 521. Telescopic detection element; 522. Linkage plate; 523. Round rod; 6. Support assembly; 601. Vertical rod; 602. Mounting frame; 603. Relative drive device; 604. Linkage block; 605. Fixing frame; 606. Bearing; 607. Belt; 608. Outer pipe; 609. Second short rod; 610. Third spring; 611. Top frame; 612. Mounting frame; 613. Lifting drive element; 614. Second connector; 615. Extrusion wheel. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0033] The present invention will be further described below with reference to embodiments.

[0034] Example: Refer to Figures 1 to 9 A dynamic balancing testing device for automotive drive shafts, comprising:

[0035] The base plate 1 and the linear drive device 2 set on the base plate 1 are provided. The linear drive device 2 is equipped with a bidirectional lead screw and a motor. The linear drive device 2 is equipped with an active drive component 3 and a driven drive component 4 that can move relative to or away from each other. The active drive component 3 is used to clamp and drive the universal joint at one end of the test vehicle drive shaft to rotate. The driven drive component 4 is used to clamp the universal joint at the other end and rotate accordingly. The driven drive component 4 is equipped with a two-dimensional drive device 402 that drives the clamping position to move up and down and left and right.

[0036] The active drive assembly 3 is equipped with a coaxial detection assembly 5. The coaxial detection assembly 5 includes two fixed rings 504 corresponding to the outer circumference of the universal joint rotation reference and the outer circumference of the adjacent shaft, respectively. Each fixed ring 504 has multiple sets of radially retractable contact wheels 516 and telescopic detection elements 520 for detecting their retraction displacement, which are symmetrically arranged along the circumference. The telescopic detection element 520 is a linear displacement sensor, and its housing is fixedly installed in the T-shaped box 512. The end of the probe abuts against the linkage plate 521.

[0037] The displacement distribution of the two fixed rings 504 is used to distinguish between fixed angular deviation and conical oscillation that changes with rotation before dynamic balancing test. The two-dimensional drive device 402 is used to drive the driven component 4 to move in the direction of reducing deviation when there is fixed angular deviation. After the adjustment is completed, the contact wheel 516 is withdrawn and the active drive component 3 drives the test vehicle drive shaft to perform dynamic balancing test.

[0038] The active drive assembly 3 includes a first movable plate 301, a first self-centering chuck 302, an external frame 303, and an active linkage shaft 304. The first movable plate 301 is fixedly installed at the output end of the linear drive device 2. The first self-centering chuck 302 is rotatably installed on one side of the first movable plate 301. The external frame 303 is fixedly installed on the other side of the first movable plate 301. The active linkage shaft 304 is rotatably installed between the external frame 303 and the first movable plate 301. One end of the active linkage shaft 304 passes through the first movable plate 301 and is fixedly connected to the first self-centering chuck 302. The other end is used to connect to the drive source.

[0039] The driven component 4 includes a second moving plate 401, a two-dimensional drive device 402, and a second self-centering chuck 403. The second moving plate 401 is fixedly installed on the output end of the linear drive device 2. The two-dimensional drive device 402 is installed on the second moving plate 401. The two-dimensional drive device 402 includes a vertical linear drive mechanism and a horizontal linear drive mechanism that are orthogonally arranged. The second self-centering chuck 403 is rotatably installed on the moving end of the two-dimensional drive device 402 so as to passively rotate with the transmission shaft of the vehicle being tested.

[0040] The two-dimensional drive device 402 consists of a vertical linear drive mechanism and a horizontal linear drive mechanism arranged orthogonally. One linear drive mechanism is arranged vertically to drive the other linear drive mechanism and the second self-centering chuck 403 to move up and down; the other linear drive mechanism is arranged horizontally to drive the second self-centering chuck 403 to move left and right. The two-dimensional drive device 402 can adjust the height and horizontal position of the driven end of the measured transmission shaft to reduce the fixed angle misalignment between the measured transmission shaft and the universal joint at the driving end.

[0041] Slide seats 501 are fixedly installed on both sides of the first movable plate 301. A slide rod 502 is slidably installed in the slide seat 501. A slide groove extending along its length is opened in the slide rod 502. A slider 503 is slidably installed in the slide groove. Two fixing rings 504 are fixedly connected to the slide rod 502 and the slider 503 respectively. One fixing ring 504 is installed between opposite sides of the slide rod 502, and the other is fixedly installed between the sliders 503 to adjust the detection position and spacing of the two fixing rings 504 in the axial direction of the tested vehicle drive shaft.

[0042] Multiple arc-shaped seats 505 are fixedly installed at intervals along the circumference on the opposite side of the fixed ring 504. Arc-shaped slide bars 506 are slidably installed in the arc-shaped seats 505. A rotating plate 507 is fixedly installed on one side of the arc-shaped slide bars 506. An existing locking element (not shown in the figure) is provided between the rotating plate 507 and the fixed ring 504 to lock the rotating plate 507 when it is rotated to a certain position. Multiple arc-shaped grooves 508 are provided at intervals along the circumference on the rotating plate 507. A sliding frame 509 is fixedly installed on the fixed ring 504 and located between adjacent arc-shaped seats 505. A sliding box 510 is slidably installed in the sliding frame 509. A round rod 522 is fixedly installed on one side of the sliding box 510. The round rod 522 is slidably disposed in the corresponding arc-shaped groove 508 so that when the rotating plate 507 rotates, it drives each sliding box 510 to move synchronously along the radial direction of the fixed ring 504.

[0043] A connecting box 511 is fixedly installed inside the sliding box 510. A block 513 is slidably installed inside the connecting box 511. The block 513 is fixedly sleeved on the outer wall of the straight rod 514. The straight rod 514 is arranged radially along the fixing ring 504. A first spring 517 is sleeved on the outer wall of the straight rod 514. The two ends of the first spring 517 are respectively connected to the connecting box 511 and the block 513. A first connector 515 is fixedly installed at one end of the straight rod 514 facing the axis of the fixing ring 504. A contact wheel 516 is rotatably installed inside the first connector 515. The contact wheel 516 is used to roll contact with the outer circumference of the universal joint rotation reference or the outer circumference of the shaft.

[0044] A T-shaped box 512 is slidably installed inside the sliding box 510 and away from the contact wheel 516. A screw for adjusting its initial position is threaded inside the T-shaped box 512. The screw is threaded into the T-shaped box 512, and its end rotatably abuts against the inner wall of the sliding box 510. A first short rod 518 is symmetrically fixed inside the T-shaped box 512. A linkage plate 521 is slidably installed on the first short rod 518. A second spring 519 is sleeved on the outer wall of the first short rod 518. The two ends of the second spring 519 are respectively connected to the T-shaped box 512 and the linkage plate 521. A telescopic detection element 520 is disposed between the T-shaped box 512 and the linkage plate 521. One end of the straight rod 514 away from the contact wheel 516 passes through the connecting box 511 and the T-shaped box 512 and abuts against the linkage plate 521.

[0045] Each fixed ring 504 has four sets of radial detection structures consisting of sliding frames 509 and round rods 522. The four sets of radial detection structures are arranged at 90-degree intervals along the circumference of the fixed ring 504 and are inclined as a whole relative to the horizontal and vertical directions. Two sets of radial detection structures arranged opposite each other form a differential detection group. The detection directions of the two differential detection groups are perpendicular to each other, and the radial detection structures in the two fixed rings 504 adopt the same circumferential installation angle to compare the center offset between the universal joint rotation reference section and the shaft detection section.

[0046] Each fixed ring 504 is provided with multiple sets of radial detection structures. Each set of radial detection structures includes a sliding frame 509, a sliding box 510, a connecting box 511, a T-shaped box 512, a square block 513, a straight rod 514, a first connector 515, a contact wheel 516, a first spring 517, a first short rod 518, a second spring 519, a telescopic detection element 520, a linkage plate 521, and a round rod 522.

[0047] It also includes a support assembly 6, which includes vertical rods 601 slidably mounted on both sides of the linear drive device 2. A mounting frame 602 is fixedly mounted between the two vertical rods 601. A relative drive device 603 is rotatably mounted inside the mounting frame 602. The relative drive device 603 uses an existing motor with a bidirectional threaded rod. The relative drive device 603 has two threads with opposite directions of rotation, and the two threads are respectively connected to a linkage block 604. A fixing frame 605 is slidably mounted inside the linkage block 604. Multiple bearings 606 are rotatably mounted inside the fixing frame 605. Two belts 607 are closed end to end and wrapped around the outer periphery of the corresponding bearings 606. The two belts 607 are arranged in opposite directions and form a limiting gap for the transmission shaft of the tested vehicle to pass through. An outer pipe 608 is provided on one side, and a second short rod 609 is slidably installed inside the outer pipe 608. One end of the second short rod 609 passes through the linkage block 604 and is connected to the fixing frame 605. The outer pipe 608 is provided with a pressure detection element, a third spring 610, a magnetorheological fluid, and an electromagnetic device acting on the magnetorheological fluid. A top frame 611 is fixedly installed on the linkage block 604, and a mounting frame 612 is fixedly installed on the top frame 611. A lifting drive element 613 is fixedly installed on the mounting frame 612. A second connector 614 is fixedly installed at the output end of the lifting drive element 613. A squeezing wheel 615 is rotatably installed inside the second connector 614. The squeezing wheel 615 is used to squeeze the corresponding belt 607 when the shaft body deflects beyond the limit gap, so as to increase the tension of the belt 607.

[0048] A sealed cavity is formed inside the outer tube 608. A piston plate or annular plate is set at one end of the second short rod 609 located inside the cavity. A damping channel for the magnetorheological fluid to pass through is opened on the piston plate, or a damping channel is formed between the annular plate and the inner wall of the outer tube 608. An electromagnetic device is set on the outer periphery of the outer tube or inside the piston plate. After the electromagnetic device is energized, it changes the apparent viscosity of the magnetorheological fluid in the damping channel. A pressure detection element is set at the end of the third spring 610 and the end wall of the cavity. The third spring 610 is used to push the fixed frame 605 to reset. The pressure detection element uses an existing pressure sensor. The lifting drive element 613 uses an existing lifting cylinder. The pressure detection element, the lifting drive element 613 and the electromagnetic device are respectively connected to the controller. When the pressure detection value exceeds the preset value, the controller controls the electromagnetic device and the lifting drive element to operate.

[0049] The working principle of this invention is as follows:

[0050] In use, the drive shaft to be tested, with universal joints at both ends, is placed between the first self-centering chuck 302 and the second self-centering chuck 403. The linear drive device 2 drives the first moving plate 301 and the second moving plate 401 to move relative to or away from each other, so that the distance between the first self-centering chuck 302 and the second self-centering chuck 403 is adapted to the length of the drive shaft to be tested. The first self-centering chuck 302 clamps the universal joint at the driving end of the drive shaft to be tested, and the second self-centering chuck 403 clamps the universal joint at the other end of the drive shaft to be tested.

[0051] The active linkage shaft 304 is connected to the output end of the motor. The motor drives the first self-centering chuck 302 to rotate through the active linkage shaft 304. The first self-centering chuck 302 drives the tested transmission shaft to rotate through the active end universal joint. The second self-centering chuck 403 is rotatably installed on the moving end of the two-dimensional drive device 402. When the tested transmission shaft rotates, the second self-centering chuck 403 passively rotates with the tested transmission shaft and does not actively apply driving torque to the other end of the tested transmission shaft.

[0052] Before conducting the formal dynamic balancing test, the coaxiality between the rotation reference of the active end universal joint and the adjacent shaft body is first detected by the coaxial detection component 5. The slide rod 502 is moved along the slide block 501, and the slider 503 is moved along the slide groove on the slide rod 502, so that the two fixing rings 504 are respectively located at the rotation reference part of the active end universal joint and the outer side of the cylindrical section of the shaft body connected to the universal joint. Among them, the fixing ring 504 near the first self-centering chuck 302 is used to detect the rotation reference of the universal joint, and the other fixing ring 504 is used to detect the shaft body. When inspecting the universal joint, the corresponding retaining ring 504 should be fitted onto the cylindrical connecting part of the universal joint, the outer circle of the flange stop, or other regular outer circle that can reflect the rotation center of the universal joint, avoiding the universal joint fork, boss, and other irregular parts. The universal joint inspection position is used to obtain the actual rotation reference of the driving end, and the shaft inspection position is used to determine the offset of the shaft section relative to the rotation reference. The inspection results of the two positions are compared to determine whether the detected offset comes from the clamping of the driving end, the universal joint swing angle, or the shaft itself.

[0053] Multiple sets of radial detection structures are spaced apart along the circumference of the fixed ring 504 and are arranged at an angle relative to the horizontal and vertical directions. Two sets of radial detection structures arranged opposite each other constitute a differential detection group, and two other sets of radial detection structures arranged opposite each other constitute another differential detection group. The detection directions of the two differential detection groups are perpendicular to each other. The movement direction of each straight rod 514 is set along the radial direction of the fixed ring 504, and its axis points to the axis of the fixed ring 504. The radial detection structures on the two fixed rings 504 adopt the same circumferential installation angle so as to compare the detection results of the universal joint rotation reference section and the shaft detection section. In one embodiment, the four sets of radial detection structures are respectively set at the upper right, upper left, lower left and lower right of the fixed ring 504, so that the two sets of detection structures opposite each other are located on the same diameter line. The inclined arrangement can avoid the sliding block 501, sliding rod 502 and the moving structures on both sides of the device, while still being able to determine the horizontal and vertical offset of the detection section through the two sets of mutually perpendicular differential detection results.

[0054] During test preparation, the rotating plate 507 is rotated, and the arc-shaped slide bar 506 slides along the arc-shaped seat 505, guiding the rotation of the rotating plate 507. During the rotation of the rotating plate 507, the inner wall of the arc-shaped groove 508 pushes the corresponding round rod 522 to move along the arc-shaped groove 508. The round rod 522 drives the sliding box 510 to move along the sliding frame 509 towards the axis of the fixed ring 504, so that each contact wheel 516 approaches the outer circumference of the universal joint rotation reference or the outer circumference of the cylindrical section of the shaft. The contact wheel 516 then engages with the outer circumference of the shaft. After touching the corresponding outer circle, the straight rod 514 drives the block 513 to move along the connecting box 511 and compresses the first spring 517, so that each contact wheel 516 in the same fixed ring 504 makes slight contact with the corresponding outer circle with basically consistent initial contact force. By adjusting the screw on the T-shaped box 512, the position of the T-shaped box 512 in the sliding box 510 is changed, so that the end of the straight rod 514 away from the contact wheel 516 abuts against the linkage plate 521, and zero-position calibration is performed on each telescopic detection element 520.

[0055] After initial calibration, the motor drives the active universal joint and the tested transmission shaft to rotate at low speed via the active linkage shaft 304 and the first self-centering chuck 302. When the outer periphery of the universal joint rotation reference or the outer periphery of the shaft detection section moves towards a certain contact wheel 516 due to radial offset, the outer periphery pushes the corresponding contact wheel 516 to retract away from the axis of the fixed ring 504. The contact wheel 516 pushes the straight rod 514 along the connecting box 511 via the first connector 515. The straight rod 514 pushes the linkage plate 521 along the first short rod 518 and compresses the second spring 519. The telescopic detection element 520 detects the displacement of the linkage plate 521 and generates a corresponding detection signal. By comparing the displacement difference of two relatively arranged telescopic detection elements 520 within the same fixed ring 504, it is possible to... It is sufficient to determine the center offset in the corresponding tilt detection direction; combined with the two sets of mutually perpendicular differential detection results, it is possible to determine the center offset in the horizontal and vertical directions of the universal joint rotation reference section or the shaft detection section. By comparing the detection results of the two fixed rings 504, it is possible to determine whether the shaft of the tested transmission shaft deviates from the rotation axis of the active end universal joint. When the detection values ​​of the universal joint rotation reference section remain relatively stable, while the differential displacement of the shaft detection section in a certain fixed direction is continuously greater than that in the opposite direction, and the maximum differential direction remains basically unchanged during the continuous rotation of the tested transmission shaft, it indicates that the rotation reference of the universal joint held by the first self-centering chuck 302 is basically coaxial with the active linkage shaft 304, but the tested transmission shaft forms an angular deviation in a fixed direction through the universal joint.

[0056] For example, when the tested drive shaft is continuously tilted upward relative to the universal joint at the driving end, the overall displacement detected by the radial detection structures on both sides of the shaft detection section at the top is greater than that on both sides of the bottom radial detection structures. This offset direction does not change sequentially with the rotation angle of the tested drive shaft. At this time, the vertical linear drive mechanism drives the second self-centering chuck 403 to move slightly downward to reduce the upward sway angle of the tested drive shaft. When the tested drive shaft tilts downward, the second self-centering chuck 403 moves upward. When the tested drive shaft tilts to the left or right, the lateral linear drive mechanism drives the second self-centering chuck 403 to move in the opposite direction to reduce the tilt. When the tested drive shaft tilts obliquely, the vertical linear drive mechanism and the lateral linear drive mechanism work together. Each adjustment of the position of the second self-centering chuck 403... Afterwards, the tested drive shaft is driven to rotate at low speed again, and the displacement of each telescopic detection element 520 in the two fixed rings 504 is compared again until the fixed direction offset of the shaft detection section is reduced to the set range, so that the shaft of the tested drive shaft gradually approaches the rotation axis of the active linkage shaft 304. When the maximum offset position of the shaft detection section passes through each group of radial detection structures in sequence with each rotation of the tested drive shaft, the corresponding contact wheel 516 generates a large retraction displacement in sequence according to the rotation sequence of the tested drive shaft. This indicates that the center of the shaft detection section moves in a circular or elliptical motion around the rotation axis of the active linkage shaft 304. This state is different from the angle deviation in the fixed direction, which may be caused by shaft bending, eccentric connection between shaft tube and universal joint, or conical oscillation of the tested drive shaft.

[0057] When the direction of maximum offset changes cyclically with the rotation of the transmission shaft under test, the two-dimensional drive device 402 does not continuously adjust the second self-centering chuck 403 according to the instantaneous displacement of each contact wheel 516. Instead, it adjusts the fixed position of the second self-centering chuck 403 according to the average center position of the shaft detection section during one revolution of the transmission shaft under test. This reduces the center offset in the fixed direction. The periodic displacement that still exists after the average center position adjustment is used as the detection result of the transmission shaft under test bending, connection eccentricity or conical oscillation. This avoids the second self-centering chuck 403 applying additional bending force to the transmission shaft under test by following the periodic oscillation of the shaft.

[0058] After the coaxial test is completed, the rotating plate 507 is rotated in the opposite direction. The arc groove 508 drives each sliding box 510 to move along the sliding frame 509 away from the axis of the fixed ring 504 through the round rod 522, so that each contact wheel 516 is separated from the outer periphery of the universal joint rotation reference and the outer periphery of the shaft. Then, the vertical moving end and the horizontal moving end of the two-dimensional drive device 402 are locked, so that the second self-centering chuck 403 is kept in the adjusted position, so as to prevent the coaxial test component 5 from continuously contacting the tested transmission shaft and changing its radial support state during the formal dynamic balance test.

[0059] For the test drive shaft that is long or exhibits significant radial sway during initial testing, the support assembly 6 is moved along the linear drive device 2 to the middle of the shaft or to an axial position with a large sway amplitude. This causes the two linkage blocks 604 to move relative to each other, so that the two belts 607 are staggered and arranged on the outer side of the shaft from opposite directions (see reference). Figure 1 or Figure 8 The belts 607 are fitted on the outer wall of the drive shaft and pulled in opposite directions, and a preset gap is formed between the two belts 607 and the outer wall of the shaft. The two belts 607 are both closed annular belts connected end to end. Each belt 607 is wrapped around the outside of multiple freely rotating guide pulleys. The guide pulleys are rotatably mounted in the fixed frame 605 through the bearings 606. When the belts 607 come into contact with the rotating outer wall of the shaft, the outer wall of the shaft drives the belts 607 to circulate along each guide pulley by friction. This reduces the continuous sliding friction between the belts 607 and the outer wall of the shaft, and reduces frictional heat, surface wear and additional braking torque.

[0060] Under normal dynamic balance test conditions, the radial vibration generated by the shaft body within the preset gap range does not contact the belt 607, and the support component 6 does not form a continuous radial constraint on the shaft body. When the radial swing of the shaft body exceeds the preset gap, the outer wall of the shaft body contacts and squeezes the belt 607 in the corresponding direction. The compressed belt 607 pushes the corresponding fixed frame 605 to move relative to the linkage block 604 while in cyclic motion.

[0061] The fixed frame 605 drives the second short rod 609 to move along the outer tube 608, and causes the third spring 610 to undergo elastic deformation. The pressure detection element in the outer tube 608 detects the force change of the second short rod 609. When the detected value exceeds the set range, the electromagnetic device generates a magnetic field and acts on the magnetorheological fluid in the outer tube 608, increasing the resistance of the magnetorheological fluid to the movement of the second short rod 609, thereby increasing the yielding damping of the fixed frame 605 and the belt 607. At the same time, the lifting drive element 613 drives the extrusion wheel 615 to approach the corresponding belt 607 through the second connector 614. The extrusion wheel 615 extrudes the outer side of the belt 607, increasing the tension of the belt 607. This flexibly limits the excessive radial runout of the shaft, preventing the shaft from hitting the equipment or causing instability in the clamping position.

[0062] When the belt 607 begins to exert a significant limiting effect on the shaft, the support assembly 6 has already changed the radial support conditions of the tested transmission shaft. Therefore, the data collected at this stage is not used as formal dynamic balance test data. The device reduces the speed of the tested transmission shaft or stops running, and checks the connection status of the first self-centering chuck 302, the second self-centering chuck 403, the tested transmission shaft, and the universal joints at both ends. After completing the coaxial adjustment again, the dynamic balance test is performed.

[0063] After the coaxial adjustment is completed, the active drive component 3 drives the test vehicle drive shaft to rise to the set test speed, and uses existing dynamic balancing testing equipment to collect vibration signals and corresponding rotation phase signals at the support positions at both ends of the test vehicle drive shaft. The existing dynamic balancing testing equipment calculates the unbalance and unbalance phase of the test vehicle drive shaft based on the collected vibration amplitude and rotation phase, and compares the test results with the set dynamic balance allowable value to determine whether the test vehicle drive shaft meets the dynamic balance requirements.

[0064] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dynamic balancing testing device for automotive drive shafts, characterized in that, include: The base plate (1) and the linear drive device (2) disposed on the base plate (1) are provided with an active drive component (3) and a driven drive component (4) that can move relative to or away from each other. The active drive component (3) is used to clamp and drive the universal joint at one end of the test vehicle drive shaft to rotate. The driven drive component (4) is used to clamp the universal joint at the other end and rotate accordingly. The driven drive component (4) is provided with a two-dimensional drive device (402) that drives the clamping position to move up and down and left and right. The active drive assembly (3) is provided with a coaxial detection assembly (5). The coaxial detection assembly (5) includes two fixed rings (504) corresponding to the outer circumference of the rotation reference of the active end universal joint and the outer circumference of the adjacent shaft respectively. Each fixed ring (504) is provided with multiple sets of radially retractable contact wheels (516) and telescopic detection elements (520) for detecting their retraction displacement, which are symmetrically arranged along the circumference. The displacement distribution of the two fixed rings (504) is used to distinguish between fixed angular deviation and conical oscillation that changes with rotation before dynamic balancing test. The two-dimensional drive device (402) is used to drive the driven component (4) to move in the direction of reducing deviation when the fixed angular deviation is in. After the adjustment is completed, the contact wheel (516) is withdrawn and the active drive component (3) drives the test vehicle drive shaft to perform dynamic balancing test.

2. The automotive driveshaft dynamic balancing testing device according to claim 1, characterized in that, The active drive assembly (3) includes a first moving plate (301), a first self-centering chuck (302), an external frame (303), and an active linkage shaft (304). The first moving plate (301) is fixedly installed at the output end of the linear drive device (2). The first self-centering chuck (302) is rotatably installed on one side of the first moving plate (301). The external frame (303) is fixedly installed on the other side of the first moving plate (301). The active linkage shaft (304) is rotatably installed between the external frame (303) and the first moving plate (301). One end of the active linkage shaft (304) passes through the first moving plate (301) and is fixedly connected to the first self-centering chuck (302). The other end is used to connect to the drive source.

3. The automotive driveshaft dynamic balancing testing device according to claim 1, characterized in that, The driven component (4) includes a second moving plate (401), a two-dimensional drive device (402), and a second self-centering chuck (403). The second moving plate (401) is fixedly installed on the output end of the linear drive device (2). The two-dimensional drive device (402) is installed on the second moving plate (401). The two-dimensional drive device (402) includes a vertical linear drive mechanism and a horizontal linear drive mechanism that are orthogonally arranged. The second self-centering chuck (403) is rotatably installed on the moving end of the two-dimensional drive device (402) so as to passively rotate with the transmission shaft of the vehicle under test.

4. The automotive driveshaft dynamic balancing test device according to claim 2, characterized in that, The first movable plate (301) is fixedly installed on both sides of the slide block (501). A slide rod (502) is slidably installed in the slide block (501). A slide groove extending along its length is opened in the slide rod (502). A slider (503) is slidably installed in the slide groove. Two fixed rings (504) are fixedly connected to the slide rod (502) and the slider (503) respectively, so as to adjust the detection position and spacing of the two fixed rings (504) in the axial direction of the test vehicle drive shaft.

5. The automotive driveshaft dynamic balancing testing device according to claim 1, characterized in that, Multiple arc-shaped seats (505) are fixedly installed at intervals along the circumference on the opposite side of the fixed ring (504). Arc-shaped slide bars (506) are slidably installed in the arc-shaped seats (505). A rotating plate (507) is fixedly installed on one side of the arc-shaped slide bars (506). Multiple arc-shaped grooves (508) are spaced apart along the circumference on the rotating plate (507). A sliding frame (509) is fixedly installed on the fixed ring (504) and located between adjacent arc-shaped seats (505). A sliding box (510) is slidably installed in the sliding frame (509). A round rod (522) is fixedly installed on one side of the sliding box (510). The round rod (522) is slidably disposed in the corresponding arc-shaped groove (508) so that when the rotating plate (507) rotates, it drives each sliding box (510) to move synchronously along the radial direction of the fixed ring (504).

6. The automotive driveshaft dynamic balancing test device according to claim 5, characterized in that, A connecting box (511) is fixedly installed inside the sliding box (510). A block (513) is slidably installed inside the connecting box (511). The block (513) is fixedly sleeved on the outer wall of the straight rod (514). The straight rod (514) is arranged radially along the fixing ring (504). A first spring (517) is sleeved on the outer wall of the straight rod (514). The two ends of the first spring (517) are respectively connected to the connecting box (511) and the block (513). A first connector (515) is fixedly installed at one end of the straight rod (514) facing the axis of the fixing ring (504). A contact wheel (516) is rotatably installed inside the first connector (515). The contact wheel (516) is used to roll contact with the outer circumference of the universal joint rotation reference or the outer circumference of the shaft.

7. The automotive driveshaft dynamic balancing test device according to claim 6, characterized in that, A T-shaped box (512) is slidably installed inside the sliding box (510) and away from the contact wheel (516). A screw for adjusting its initial position is threaded inside the T-shaped box (512). A first short rod (518) is symmetrically fixed inside the T-shaped box (512). A linkage plate (521) is slidably installed on the first short rod (518). A second spring (519) is sleeved on the outer wall of the first short rod (518). The two ends of the second spring (519) are respectively connected to the T-shaped box (512) and the linkage plate (521). The telescopic detection element (520) is disposed between the T-shaped box (512) and the linkage plate (521). One end of the straight rod (514) away from the contact wheel (516) passes through the connecting box (511) and the T-shaped box (512) and abuts against the linkage plate (521).

8. The automotive driveshaft dynamic balancing test device according to claim 7, characterized in that, Each of the fixed rings (504) is provided with four sets of radial detection structures consisting of the sliding frame (509) and the round rod (522). The four sets of radial detection structures are arranged at 90-degree intervals along the circumference of the fixed ring (504) and are inclined as a whole relative to the horizontal and vertical directions. Two sets of radial detection structures arranged opposite each other constitute a differential detection group. The detection directions of the two sets of differential detection groups are perpendicular to each other, and the radial detection structures in the two fixed rings (504) adopt the same circumferential installation angle to compare the center offset between the universal joint rotation reference section and the shaft detection section.

9. The automotive driveshaft dynamic balancing testing device according to claim 1, characterized in that, It also includes a support assembly (6), which includes vertical rods (601) slidably mounted on both sides of the linear drive device (2), a mounting frame (602) fixedly mounted between the two vertical rods (601), a relative drive device (603) rotatably mounted in the mounting frame (602), the relative drive device (603) having two threads with opposite directions of rotation, the two threads being respectively connected to a linkage block (604); a fixing frame (605) slidably mounted in the linkage block (604), a plurality of bearings (606) rotatably mounted in the fixing frame (605), two belts (607) closing end to end and wrapped around the outer periphery of the corresponding bearings (606), the two belts (607) being arranged in opposite directions and forming a limiting gap for the transmission shaft of the tested vehicle to pass through; an outer connecting pipe (608) is provided on one side of the linkage block (604), the outer connecting pipe (608) 08) A second short rod (609) is slidably installed inside. One end of the second short rod (609) passes through the linkage block (604) and is connected to the fixed frame (605). The outer pipe (608) is provided with a pressure detection element, a third spring (610), a magnetorheological fluid, and an electromagnetic device acting on the magnetorheological fluid. A top frame (611) is fixedly installed on the linkage block (604). A mounting frame (612) is fixedly installed on the top frame (611). A lifting drive element (613) is fixedly installed on the mounting frame (612). A second connector (614) is fixedly installed at the output end of the lifting drive element (613). A squeezing wheel (615) is rotatably installed inside the second connector (614). The squeezing wheel (615) is used to squeeze the corresponding belt (607) when the shaft body deflects beyond the limit gap, so as to increase the tension of the belt (607).

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