Auxiliary assembly device for universal shaft of engine test bed
By designing components such as a base, movable support, and bidirectional displacement mechanism on the engine test bench, and combining them with a closed-loop servo control system, high-precision automatic centering and dynamic posture correction of the universal joint were achieved. This solved the problems of low precision and poor efficiency in traditional assembly, and improved the stability of the transmission system and the service life of the universal joint.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-03
- Publication Date
- 2026-03-27
AI Technical Summary
The assembly of universal joints on traditional engine test benches relies on manual experience, resulting in low assembly accuracy and poor efficiency. It is difficult to ensure that the two ends of the universal joint are precisely aligned with the engine output shaft and load shaft, leading to coaxiality deviation and vibration and abnormal wear of the transmission system. Furthermore, existing devices lack dynamic position correction capabilities.
The design employs a combination of base, movable support, bidirectional displacement mechanism, bearing connection structure and positioning constraint mechanism. By establishing a horizontal reference plane and a closed-loop servo control system, it achieves high-precision automatic alignment and dynamic posture correction at both ends of the universal joint, eliminates assembly deviations and torsional stress, and ensures the coaxiality of the transmission system.
It achieves high-precision automatic alignment between the universal joint and the engine and load shaft, eliminating assembly deviations and torsional stress, improving the smoothness of the transmission system and the life of the universal joint, and reducing interference and adjustment time during the testing process.
Smart Images
Figure CN121740446A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of engine testing, in particular to a kind of engine test bench universal shaft auxiliary assembly device. BACKGROUND
[0002] Traditional engine test bench universal shaft assembly relies on manual experience, and assembly precision is low and efficiency is poor. Manual adjustment is difficult to ensure that the two ends of the universal shaft are accurately centered with the engine output shaft and the load shaft, which can easily lead to coaxiality deviation. Assembly error causes transmission system vibration and abnormal wear. When adjusting the position of the two ends of the universal shaft step by step, the cumulative error is further amplified. The support structure can interfere with the freedom of the rotating parts during the test phase, and the tooling needs to be repeatedly disassembled and switched. The existing device lacks dynamic pose correction capability, and thermal deformation and vibration can destroy the initial assembly precision. SUMMARY
[0003] The present application provides a kind of engine test bench universal shaft auxiliary assembly device, comprising: Base, top surface constitutes horizontal reference surface, and defines horizontal plane coordinate system; Movable support, set on the base by two-way displacement mechanism; Two-way displacement mechanism, including horizontal drive assembly and vertical drive assembly, the horizontal drive assembly is fixedly connected with the base and the output end is connected with the vertical drive assembly, and the output end of the vertical drive assembly is connected with the movable support;Wherein, the horizontal drive assembly drives the movable support to displace along the X axis direction of horizontal reference surface, and the vertical drive assembly drives the movable support to displace along the Y axis direction perpendicular to horizontal reference surface; Bearing connection structure, set on the upper end of movable support, and the inner ring is used to sleeve and radially constrain the central shaft section of universal shaft; Positioning constraint mechanism, including first theoretical installation pose and second theoretical installation pose set on the base, respectively defining the three-dimensional coordinates and axial direction of the center points of the end faces of engine output shaft and load shaft in the horizontal plane coordinate system;Wherein, when the two-way displacement mechanism drives the movable support to move, the center points of the connecting end portions of the two ends of the universal shaft are simultaneously reached to the corresponding theoretical installation pose coordinate points, and the axial direction of the connecting end portion is collinear with the axial direction of the corresponding theoretical installation pose.
[0004] Wherein, the movable support includes: seat body and disc body;The seat body is supported on the two-way displacement mechanism, and is fixedly connected with the output end of the vertical drive assembly, and the top of the seat body is provided with a half groove body;The disc body is adaptively embedded in the half groove body, and the center of the disc body is provided with a coaxial through hole;The outer ring of the bearing connection structure is fixedly connected to the inner wall of the through hole, and the axis of the inner ring of the bearing connection structure coincides with the axis of the through hole.
[0005] The inner ring width center surface of the bearing connecting structure is coplanar with the plane where the center of gravity of the universal shaft is located, and the inner ring of the bearing connecting structure is symmetrically sleeved on the central shaft section of the universal shaft, so that the connection end portions at both ends of the universal shaft are balanced with respect to the support point moment of the bearing connecting structure.
[0006] The inner ring width center surface of the bearing connecting structure passes through the center of gravity point of the universal shaft; the symmetry error of the inner ring symmetrically sleeved on the central shaft section of the universal shaft is ≤0.05 mm; and the unbalanced moment of the bearing connecting structure support point at both ends of the universal shaft is ≤0.01 N·m.
[0007] The mass of the disc body is less than 1 / 5 of the mass of the universal shaft, and a damping shock-absorbing layer is arranged between the disc body and the half-groove body; the damping shock-absorbing layer is continuously attached between the bottom surface of the disc body and the bottom surface of the half-groove body, the thickness of the damping shock-absorbing layer is 2-5 mm, the elastic modulus is 0.1-1 GPa, and the loss factor is not less than 0.3.
[0008] The horizontal driving assembly includes a guide rail arranged in parallel to the horizontal reference surface X-axis direction, a sliding block in sliding cooperation with the guide rail, and a first power unit driving the sliding block to displace along the guide rail; the vertical driving assembly includes a support frame fixedly connected with the sliding block, a lifting mechanism arranged on the support frame, and a second power unit driving the lifting mechanism to displace along the Y-axis direction; and the top output end of the lifting mechanism is rigidly connected with the movable support.
[0009] When the engine rotates for testing, the disc body is maintained in bearing connection with the universal shaft, and the disc body is separated from the half-groove body or the disc body is supported by the half-groove body.
[0010] When the disc body needs to be separated from the half-groove body when the engine rotates for testing, the vertical driving assembly drives the seat body to displace by a set distance in the negative direction of the Y-axis, so that the disc body is separated from the half-groove body.
[0011] The bidirectional displacement mechanism is connected with a closed-loop servo control system; the closed-loop servo control system obtains actual pose data of the connection end portions at both ends of the universal shaft in real time, compares the actual pose data with the theoretical installation pose, generates linkage control instructions to drive the horizontal driving assembly and the vertical driving assembly to displace synchronously.
[0012] The application establishes a horizontal reference plane uniform space reference system through the top surface of the base. The two-way displacement mechanism drives the movable support to move accurately along the horizontal X-axis and the vertical Y-axis. The bearing connection structure radially restricts the center shaft section of the universal shaft to form a rigid fulcrum. The positioning constraint mechanism predefines the theoretical installation pose coordinates and the axial direction of both ends. The two-way displacement mechanism synchronously controls the center points of the connecting ends at both ends of the universal shaft to reach the theoretical coordinate points and the axial direction to be collinear. This process realizes full-automatic high-precision centering and eliminates assembly deviation and torsional stress. The split design of the movable support allows the disc body to be separated from the seat body and freely rotate with the universal shaft, and the test switching time is zero. The closed-loop servo system compares the actual pose with the theoretical value in real time and dynamically compensates for the deviation. The bearing support structure with coincident gravity centers suppresses the rotational inertia moment and improves the transmission stability. The damping shock-absorbing layer blocks the transmission of engine vibration to the universal shaft. The device ensures the coaxiality of the transmission system and prolongs the service life of the universal shaft. BRIEF DESCRIPTION OF DRAWINGS
[0013] Figure 1 A simplified schematic diagram of an auxiliary assembly device for a universal shaft of an engine test bench is proposed in the application; Figure 2 A schematic diagram of an engine connected to a load through a universal shaft corresponding to the auxiliary assembly device for a universal shaft of an engine test bench is proposed in the application; Figure 3 A one-directional diagram of an auxiliary assembly device for a universal shaft of an engine test bench is proposed in the application; Figure 4 A one-directional diagram of an auxiliary assembly device for a universal shaft of an engine test bench is proposed in the application. DETAILED DESCRIPTION
[0014] REFERENCES Figure 1The application provides an auxiliary assembling device for a universal shaft 5 of an engine 6 test bench, which comprises a base 1, a movable support 2, a bidirectional displacement mechanism 3, a bearing connecting structure 4 and a positioning constraint mechanism. The top surface of the base 1 constitutes a horizontal reference surface and defines a horizontal plane coordinate system. The movable support 2 is arranged on the base 1 through the bidirectional displacement mechanism 3. The bidirectional displacement mechanism 3 comprises a horizontal driving assembly 31 and a vertical driving assembly 32. The horizontal driving assembly 31 is fixedly connected with the base 1 and has an output end connected with the vertical driving assembly 32. The output end of the vertical driving assembly 32 is connected with the movable support 2. The horizontal driving assembly 31 drives the movable support 2 to displace along the X-axis direction of the horizontal reference surface, and the vertical driving assembly 32 drives the movable support 2 to displace along the Y-axis direction perpendicular to the horizontal reference surface. The bearing connecting structure 4 is arranged on the upper end of the movable support 2, and an inner ring 41 of the bearing connecting structure 4 is used for sleeving and radially constraining a central shaft section of the universal shaft 5. The positioning constraint mechanism comprises a first theoretical installation pose and a second theoretical installation pose arranged on the base 1, which respectively define the three-dimensional coordinates and the axial direction of the center points of the end surfaces of the output shaft of the engine 6 and the end surfaces of the shaft of the load 7 in the horizontal plane coordinate system. When the bidirectional displacement mechanism 3 drives the movable support 2 to move, the center points of the connecting end portions at both ends of the universal shaft 5 synchronously reach the corresponding theoretical installation pose coordinate points, and the axial directions of the connecting end portions are collinear with the axial directions of the corresponding theoretical installation poses. When the device works, the top surface of the base 1 establishes the horizontal reference surface coordinate system, and the movable support 2 is driven to move by the bidirectional displacement mechanism 3. The horizontal driving assembly 31 pushes the vertical driving assembly 32 to displace along the X-axis direction of the horizontal reference surface, and the vertical driving assembly 32 drives the movable support 2 to ascend and descend along the Y-axis direction of the vertical reference surface. The central shaft section of the universal shaft 5 is radially constrained and fixed on the upper end of the movable support 2 by the inner ring 41 of the bearing connecting structure 4, and the target positions of the connecting end portions at both ends thereof are determined by the three-dimensional coordinates and the axial direction of the center points of the end surfaces of the output shaft of the engine 6 and the end surfaces of the shaft of the load 7 which are defined by the positioning constraint mechanism in advance. The bidirectional displacement mechanism 3 controls the movement of the movable support 2 in linkage, so that the center points of the connecting end portions at both ends of the universal shaft 5 synchronously reach the corresponding theoretical installation pose coordinate points, and the axial directions of the connecting end portions are completely coincident with the axial directions of the theoretical installation poses. Therefore, the high-precision automatic centering of the universal shaft 5 with the engine 6 and the load 7 shaft is realized, the assembling deviation and the torsional stress are eliminated, and the coaxiality of the transmission system is ensured. Meanwhile, the movable support 2 does not follow the movement of the universal shaft 5 when the universal shaft 5 rotates due to the existence of the bearing connecting structure 4, so that the influence of the movable support 2 on the rotation of the universal shaft 5 is reduced.
[0015] Further, the movable support 2 comprises a seat body 21 and a disc body 22; the seat body 21 is supported on the bidirectional displacement mechanism 3 and fixedly connected with the output end of the vertical driving assembly 32, and a half groove 211 is arranged on the top of the seat body 21; the disc body 22 is adapted to be embedded in the half groove 211, and a coaxial through hole is arranged in the center of the disc body 22; the outer ring 42 of the bearing connecting structure 4 is fixedly connected to the inner wall of the through hole, and the axis of the inner ring 41 of the bearing connecting structure 4 coincides with the axis of the through hole. When the movable support 2 is implemented, the seat body 21 is directly driven by the vertical driving assembly 32, and the half groove 211 on the top of the seat body 21 supports the bottom of the disc body 22. The disc body 22 is embedded by the shape of the bottom and the half groove 211, and the horizontal direction is kept from being deviated. The outer ring 42 of the bearing connecting structure 4 is accurately installed in the center through hole of the disc body 22, and the axis of the inner ring 41 of the bearing always coincides with the axis of the through hole. After the central shaft segment of the universal shaft 5 is installed in the inner ring 41 of the bearing, the disc body 22 will transmit the radial constraint to the universal shaft 5. When it is needed to be separated, the seat body 21 is lowered to make the half groove 211 and the disc body 22 out of contact, and the disc body 22 rotates independently with the universal shaft 5. This structure not only guarantees the assembly stability, but also realizes the quick switching of the test mode, and ensures the accurate controllability of the freedom degree of the universal shaft 5. Since the disc body 22 is connected by the half groove 211 and belongs to movable connection, it is convenient to replace different disc bodies 22, that is, to replace different universal shafts 5 for experiment.
[0016] Further, the width center surface of the inner ring 41 of the bearing connecting structure 4 is coplanar with the plane where the center of gravity of the universal shaft 5 is located, and the inner ring 41 of the bearing connecting structure 4 is symmetrically sleeved on the central shaft segment of the universal shaft 5, so that the moment balance of the connecting end portions at both ends of the universal shaft 5 relative to the support point of the bearing connecting structure 4 is achieved. Further, the center of gravity point of the universal shaft 5 passes through the width center surface of the inner ring 41 of the bearing connecting structure 4; the symmetry error of the inner ring 41 symmetrically sleeved on the central shaft segment of the universal shaft 5 is ≤0.05mm; and the unbalanced moment of the universal shaft 5 at both ends relative to the support point of the bearing connecting structure 4 is ≤0.01N·m. When the bearing connecting structure 4 is implemented, the width center surface of the inner ring 41 is accurately positioned at the center of gravity point of the universal shaft 5, so as to ensure that the support point and the center of gravity are spatially coincident. The inner ring 41 is symmetrically sleeved along the central shaft segment of the universal shaft 5, and the symmetry error is strictly controlled. The mass distribution of the connecting end portions at both ends of the universal shaft 5 relative to the support point is balanced, and the centrifugal forces are counteracted when rotating. Thus, a self-balancing structure is formed, and there is no additional inertia moment when the universal shaft 5 rotates at high speed. This state eliminates the vibration source of the shafting and guarantees the smoothness of transmission.
[0017] Further, the disc body 22 has a mass less than 1 / 5 of the mass of the universal shaft 5, and a damping shock-absorbing layer is arranged between the disc body 22 and the half-groove body 211; the damping shock-absorbing layer is continuously attached between the bottom surface of the disc body 22 and the bottom surface of the half-groove body 211, has a thickness of 2-5 mm, an elastic modulus of 0.1-1 GPa, and a loss factor not less than 0.3. When the damping shock-absorbing layer is implemented, a specific elastic modulus material is continuously laid between the contact surface of the disc body 22 and the half-groove body 211. The mass of the disc body 22 is significantly less than that of the universal shaft 5, ensuring that the shock-absorbing action does not affect the main body pose of the universal shaft 5. The layered structure with a specific thickness absorbs high-frequency vibration energy, and the loss factor index controls the vibration transmission rate. The elastic modulus of the material also maintains the radial constraint rigidity, avoiding the positioning deviation caused by the softening of the support. The disc body 22 and the universal shaft 5 form an inertia isolation system, and the vibration of the engine 6 is converted into heat energy and dissipated through the damping layer. This structure maintains the stable space reference of the central shaft section of the universal shaft 5, and ensures that the pose synchronization accuracy is not disturbed.
[0018] Further, the horizontal driving assembly 31 comprises a guide rail arranged in parallel to the horizontal reference surface X, a sliding block 311 in sliding cooperation with the guide rail, and a first power unit 312 for driving the sliding block 311 to displace along the guide rail; the vertical driving assembly 32 comprises a support frame 323 fixedly connected with the sliding block 311, a lifting mechanism 321 arranged on the support frame 323, and a second power unit 322 for driving the lifting mechanism 321 to displace along the Y-axis direction; the top output end of the lifting mechanism 321 is rigidly connected with the movable support 2.
[0019] Further, when the engine 6 rotates for testing, the disc body 22 is in bearing connection with the universal shaft 5 and the disc body 22 is separated from the half groove body 211 or the disc body 22 is supported by the half groove body 211. Further, when the disc body 22 needs to be separated from the half groove body 211 when the engine 6 rotates for testing, the vertical driving assembly 32 drives the seat body 21 to move along the Y-axis negative direction by a certain distance, so that the disc body 22 is separated from the half groove body 211. Further, the bidirectional displacement mechanism 3 is connected with a closed-loop servo control system; the closed-loop servo control system obtains the actual pose data of the connecting end portions at both ends of the universal shaft 5 in real time, compares the deviation with the theoretical installation pose, generates linkage control instructions to drive the horizontal driving assembly 31 and the vertical driving assembly 32 to move synchronously. When the device is implemented, the closed-loop servo control system continuously collects the actual pose of the connecting end portions at both ends of the universal shaft 5. The system compares the coordinate and axial deviation of the measured data with the preset theoretical installation pose. The linkage control instructions synchronously adjust the actions of the horizontal driving assembly 31 and the vertical driving assembly 32. The movable support 2 is corrected in real time under the driving of the bidirectional displacement mechanism 3. If the disc body 22 needs to be separated during the testing of the engine 6, the vertical driving assembly 32 drives the seat body 21 to move vertically downward. The downward movement of the seat body 21 makes the half groove body 211 and the disc body 22 in clearance disengagement. The disc body 22 is in bearing connection and rotates freely with the universal shaft 5. After the testing is completed, the seat body 21 is lifted to make the half groove body 211 support the disc body 22 again. The dynamic control does not need to interrupt the testing process during the whole process, which ensures that the collinearity precision and the rotation freedom degree of the universal shaft 5 are synchronized to meet the standards.
[0020] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacement or change according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.
Claims
1. A universal joint auxiliary assembly device for an engine test bench, characterized in that, include: The base (1) has a top surface that forms a horizontal reference plane and defines a horizontal coordinate system; The movable support (2) is mounted on the base (1) via a bidirectional displacement mechanism (3); The bidirectional displacement mechanism (3) includes a horizontal drive assembly (31) and a vertical drive assembly (32). The horizontal drive assembly (31) is fixedly connected to the base (1) and its output end is connected to the vertical drive assembly (32). The output end of the vertical drive assembly (32) is connected to the movable support (2). The horizontal drive assembly (31) drives the movable support (2) to move along the X-axis direction of the horizontal reference plane, and the vertical drive assembly (32) drives the movable support (2) to move along the Y-axis direction perpendicular to the horizontal reference plane. The bearing connection structure (4) is located at the upper end of the movable support (2), and its inner ring (41) is used to fit and radially constrain the central shaft section of the universal joint (5); The positioning constraint mechanism includes a first theoretical installation pose and a second theoretical installation pose set on the base (1), which respectively define the three-dimensional coordinates and axial direction of the center point of the output shaft end face of the engine (6) and the center point of the load (7) shaft end face in the horizontal coordinate system; wherein, when the bidirectional displacement mechanism (3) drives the movable support (2) to move, the center points of the connecting ends of the universal joint (5) reach the corresponding theoretical installation pose coordinate points synchronously, and the axial direction of the connecting ends is collinear with the axial direction of the corresponding theoretical installation pose.
2. The auxiliary assembly device as claimed in claim 1, characterized in that, The movable support (2) includes: a seat (21) and a disc (22); the seat (21) is supported on the bidirectional displacement mechanism (3) and is fixedly connected to the output end of the vertical drive assembly (32); the top of the seat (21) is provided with a semi-groove (211); the bottom of the disc (22) is adapted to fit into the semi-groove (211), and the center of the disc (22) is provided with a coaxial through hole; the outer ring (42) of the bearing connection structure (4) is fixedly connected to the inner wall of the through hole, and the axis of the inner ring (41) of the bearing connection structure (4) coincides with the axis of the through hole.
3. The auxiliary assembly device as claimed in claim 1, characterized in that, The center plane of the inner ring (41) of the bearing connection structure (4) is coplanar with the plane of the center of gravity of the universal shaft (5), and the inner ring (41) of the bearing connection structure (4) is symmetrically fitted onto the central shaft section of the universal shaft (5), so that the torque of the connecting ends of the universal shaft (5) at both ends relative to the support point of the bearing connection structure (4) is balanced.
4. The auxiliary assembly device according to claim 3, characterized in that, The center plane of the inner ring (41) of the bearing connection structure (4) passes through the center of gravity of the universal shaft (5); the symmetry error of the inner ring (41) symmetrically fitted onto the central shaft section of the universal shaft (5) is ≤0.05mm; the unbalanced torque of the two ends of the universal shaft (5) on the support point of the bearing connection structure (4) is ≤0.01N·m.
5. The auxiliary assembly device as claimed in claim 2, characterized in that, The mass of the disc (22) is less than 1 / 5 of the mass of the universal joint (5), and a damping layer is provided between the disc (22) and the semi-groove (211); the damping layer is continuously attached between the bottom surface of the disc (22) and the bottom surface of the semi-groove (211), the thickness of the damping layer is 2-5mm, the elastic modulus is 0.1-1GPa, and the loss factor is not less than 0.
3.
6. The auxiliary assembly device as claimed in claim 1, characterized in that, The horizontal drive assembly (31) includes a guide rail arranged parallel to the X-axis direction of the horizontal reference plane, a slider (311) that slides with the guide rail, and a first power unit (312) that drives the slider (311) to move along the guide rail; the vertical drive assembly (32) includes a support frame (323) fixedly connected to the slider (311), a lifting mechanism (321) provided on the support frame (323), and a second power unit (322) that drives the lifting mechanism (321) to move along the Y-axis direction; the top output end of the lifting mechanism (321) is rigidly connected to the movable support (2).
7. The auxiliary assembly device as claimed in claim 2, characterized in that, When the engine (6) is rotated during the test, the disc (22) and the universal joint (5) maintain a bearing connection and the disc (22) is separated from the semi-groove (211) or the disc (22) is supported by the semi-groove (211).
8. The auxiliary assembly device according to claim 7, characterized in that, When the engine (6) needs to be rotated during the test, the disc (22) needs to be separated from the semi-groove (211). The vertical drive assembly (32) drives the seat (21) to move a set distance along the negative Y-axis so that the disc (22) can be separated from the semi-groove (211).
9. The auxiliary assembly device according to claim 1, characterized in that, The bidirectional displacement mechanism (3) is connected to the closed-loop servo control system. The closed-loop servo control system acquires the actual position and posture data of the connection ends at both ends of the universal joint (5) in real time, compares the deviation with the theoretical installation position and posture, and generates linkage control commands to drive the horizontal drive component (31) and the vertical drive component (32) to move synchronously.