Rotary bending testing device
By combining servo actuators, force sensors, and a three-degree-of-freedom platform, the problems of complex structure and inconvenient adjustment of loading torque in existing 4-point bending durability testing equipment for motor shafts have been solved, realizing real-time and accurate adjustment of loading torque and improving testing accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-15
- Publication Date
- 2026-03-27
AI Technical Summary
Existing 4-point bending durability testing equipment for motor shafts has a complex structure, is inconvenient to adjust the loading torque, and cannot be adjusted accurately in real time.
By combining servo actuators and force sensors, parallel torque loading is achieved through elastic connectors. Combined with displacement sensors and a three-degree-of-freedom platform, the loading torque can be monitored and adjusted in real time, reducing equipment complexity and improving accuracy.
It enables real-time and precise adjustment of the loading torque, reduces equipment vibration, improves testing accuracy and safety, and enhances ease of operation.
Smart Images
Figure CN121740639A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of four-point bending test, and particularly relates to a rotary bending test device. BACKGROUND
[0002] When a four-point bending durability test is performed on a rotating shaft of a motor, the test method specified in DIN50113 5.2.1 is mainly referred to, the device structure is relatively complex, and the bending moment loading method is generally a weight, it is inconvenient to adjust the loading moment, and the loading moment value cannot be adjusted in real time and at will. SUMMARY
[0003] In view of the deficiencies in the prior art, the present application aims to provide a rotary bending test device.
[0004] To achieve the above technical purpose, the technical scheme adopted by the present application is as follows: A rotary bending test device, comprising a force arm rod perpendicular to the axis of the test shaft, the force arm rod transmitting a moment to the test shaft; The end of the force arm rod away from the test shaft is provided with a servo actuator for applying a push-pull force, the output shaft of the servo actuator is connected to a force sensor, the other end of the force sensor is connected to an elastic connector, the elastic connector is connected to the force arm rod, and the direction of the force output by the servo actuator is parallel to the axial direction of the test shaft.
[0005] In the present application, the force output by the servo actuator is loaded onto the force arm rod through the force sensor and the elastic connector, and then the moment is transmitted to the test shaft by the force arm rod, thereby completing the point bending durability test. The moment loading method of the test shaft is parallel to the axial direction, and the test shaft moment is loaded by applying a pushing force or a pulling force to the end of the force arm rod. The test shaft moment T = loading force F * force arm length; In order to more accurately control the loading force, a servo actuator is selected to improve the accuracy, and a force sensor is arranged to detect the actual applied loading force in real time, which is used as feedback to the servo actuator to form a closed loop. The elastic connector is used for transmitting the loading force of the servo actuator through deformation of the elastic connector, and can assist in improving the accuracy and stability of the loading force, because if the output end of the servo actuator is directly connected with the force arm rod, a slight movement of the output end of the servo actuator will transmit a large value of force, which causes the servo actuator to move only in a small stroke range, and the accuracy of the servo actuator is greatly required, and the deformation of the elastic connector is used to indirectly apply the force, so that the servo actuator can control the value of the loading force by controlling the position of the output end, and the position control is relatively wide, the accuracy requirement of the servo actuator is reduced, and the force sensor can feed back the force value in real time, when the test shaft is deformed to cause the elastic connector to deform and the loading force to change, the force sensor can feed back the change to the servo actuator in time, the servo actuator adjusts the position to make the loading force reach the required value, which greatly adapts to the dynamic change characteristics in the test process and improves the accuracy of the test.
[0006] As a preferred technical solution of the present application, a displacement sensor is arranged to monitor the displacement change of the side of the force arm rod acted by the servo actuator.
[0007] In the present application, the test shaft is deformed under the action of the force moment, and the force arm rod moves, when the test shaft reaches a certain deformation, the test can be stopped, the displacement sensor judges the displacement change of the force arm rod to judge the deformation process of the test shaft. Specifically, the displacement sensor reads the displacement of the end of the force arm rod in real time, and the displacement can be used to judge whether the test shaft fails in the test process and issue a command to stop the test.
[0008] As a preferred technical solution of the present application, a floating bearing seat is arranged to provide a supporting force to one end of the test shaft, and a three-degree-of-freedom platform is arranged to support the floating bearing seat, and the three-degree-of-freedom platform has the freedom of X-direction movement, Y-direction movement and Z-direction rotation.
[0009] In the present application, the floating bearing seat provides a supporting force, which can be provided indirectly, that is, the floating bearing seat is connected with the test shaft through an intermediate connecting piece to provide a supporting force, because if the test shaft is directly installed on the floating bearing seat, it will be difficult to disassemble and assemble, which is not conducive to the test of multiple test shafts. A three-degree-of-freedom platform allows the floating bearing housing to have X-axis movement, Y-axis movement, and Z-axis rotation. This multi-degree-of-freedom floating structure can adapt to the deformation displacement in the X-axis, deformation displacement in the Y-axis, and rotation angle changes in the Z-axis after the test shaft is subjected to a loading force during the test. Specifically, it can automatically adapt to the instantaneous position and attitude of the test shaft, and minimize the generation of forces other than the loading force, thereby improving the accuracy of point bending durability testing by reducing interference forces.
[0010] In some optional examples, the three-degree-of-freedom platform includes an X-axis displacement mechanism, a Y-axis displacement mechanism, and a Z-axis rotation mechanism. The floating bearing seat is arranged at the rotating end of the Z-axis rotation mechanism, and the Z-axis rotation mechanism is arranged on the cross slide formed by the X-axis displacement mechanism and the Y-axis displacement mechanism. The X-axis displacement mechanism may be below the Y-axis displacement mechanism, or the Y-axis displacement mechanism may be below the X-axis displacement mechanism.
[0011] The beneficial effects of this invention are: it reduces the structural complexity of the equipment, enables real-time and arbitrarily precise adjustment of the loading torque, provides real-time feedback on deformation during the test, and effectively reduces equipment vibration, improves safety, and enhances operator convenience. Attached Figure Description
[0012] The present invention can be further illustrated by the non-limiting embodiments given in the accompanying drawings; Figure 1 This is an isometric view of an embodiment of the present invention; Figure 2 This is a front view of an embodiment of the present invention; Figure 3 This is a top view of an embodiment of the present invention; Figure 4 This is a graph showing the change of test data over time in an embodiment of the present invention; The symbols for the main components are explained below: 1. Rotary drive motor; 2. Test axis; 3. Fix the bearing housing; 4. Floating bearing housing; 5. Lever arm; 6. Displacement sensor; 7. Flexible connector; 8. Force sensor; 9. Servo actuator; 10. Protective support; 11. Vibration sensor; 12. Three-degree-of-freedom platform; 121. X-axis displacement mechanism; 122. Y-axis displacement mechanism; 123. Z-axis rotation mechanism; 13. Rotating shaft two; 14. Rotating shaft one. Detailed Implementation
[0013] The technical solutions of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation methods or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein. Example
[0014] like Figure 1 As shown, this embodiment provides a rotational bending test device, including a protective bracket 10, a displacement sensor 6, and a lever arm 5 perpendicular to the axis of the test shaft 2, the lever arm 5 transmitting torque to the test shaft 2; A servo actuator 9 for applying push and pull force is arranged at the end of the lever arm 5 away from the test axis 2. The output shaft of the servo actuator 9 is connected to the force sensor 8. The other end of the force sensor 8 is connected to the elastic connector 7. The elastic connector 7 is connected to the lever arm 5. The direction of the output force of the servo actuator 9 is parallel to the axis of the test axis 2. Displacement sensor 6 monitors the displacement change on the side of lever arm 5 that is acted upon by servo actuator 9; The protective bracket 10 is provided with a through hole, the inner diameter of which is larger than the diameter of the test shaft 2, and the through hole is used for the test shaft 2 to pass through.
[0015] In this embodiment, the force output by the servo actuator 9 is applied to the lever arm 5 through the force sensor 8 and the elastic connector 7, and then the lever arm 5 transmits the torque to the test shaft 2 to complete the 4-point bending durability test. The torque loading method of the test shaft 2 is parallel to the axial direction, and the torque of the test shaft 2 is achieved by applying a pushing or pulling force to the end of the lever arm 5. The torque of the test shaft 2 T = loading force F * lever arm length; To achieve more precise control of the loading force, a servo actuator 9 was selected to improve accuracy. At the same time, a force sensor 8 was set up to detect the actual applied loading force in real time. This data serves as feedback to the servo actuator 9 to form a closed loop. The function of the elastic connector 7 is to transmit the loading force of the servo actuator 9 through its own deformation, which can help improve the accuracy and stability of the force loading. This is because if the output end of the servo actuator 9 is directly connected to the lever arm 5, a slight movement of the output end of the servo actuator 9 will transmit a large force, which will limit the movement of the servo actuator 9 to a very small stroke range, placing extremely high demands on the accuracy of the servo actuator 9. However, by applying force indirectly through the deformation of the elastic connector 7, the servo actuator 9 can control the magnitude of the loading force by controlling the position of its own output end. Moreover, this position control is more flexible, reducing the accuracy requirements of the servo actuator 9. In addition, the force sensor 8 can provide real-time feedback on the magnitude of the force. When the test shaft 2 deforms during testing, causing the elastic connector 7 to deform accordingly and the loading force to change, the force sensor 8 can promptly provide feedback on this change to the servo actuator 9, which can then adjust its position to achieve the required loading force value. This greatly adapts to the dynamic changes during the testing process and improves the accuracy of the test. When the test shaft 2 is subjected to torque, it will deform, causing the lever arm 5 to move. Once the test shaft 2 has reached a certain deformation, the test can be stopped. The displacement sensor 6 judges the change in distance between itself and the lever arm 5 to determine the deformation process of the test shaft 2. Specifically, the displacement sensor 6 reads the displacement of the end of the lever arm 5 in real time, and can use the read displacement to determine whether the test shaft 2 has failed during the test, and issue a command to stop the test; The protective bracket 10 serves as external protection to prevent accidental ejection of the test shaft 2 after its failure, thus avoiding safety accidents. The protective bracket 10 can effectively mechanically block the test shaft 2.
[0016] In some optional instances, the servo actuator 9 is selected from servo devices that output linear motion, such as servo electric cylinders and servo presses.
[0017] In some optional instances, a test chamber is also arranged on the protective bracket 10 to completely cover the test axis 2, thereby increasing test safety. Example
[0018] like Figures 1 to 4 As shown, Figure 4 It shows how the values change over time. Figure 4 middle, The red line represents the applied torque value (in N·m). The blue line represents the loading speed (in rpm) on test shaft 2. The purple line represents the displacement of the end of the lever arm 5 as read in real time by the displacement sensor 6 (in mm). The pink line represents the vibration level of the floating bearing housing 4 as monitored by the vibration sensor 11; The green line represents the vibration level of the fixed bearing housing 3.
[0019] This embodiment provides a rotary bending test device, which differs from Embodiment 1 in that it includes a rotary drive motor 1, a fixed bearing seat 3, a floating bearing seat 4, and a three-degree-of-freedom platform 12 for supporting the floating bearing seat 4. The fixed bearing housing 3 is rotatably connected to the rotating shaft 14, and the rotary drive motor 1 is connected to the rotating shaft 14 through a coupling. The floating bearing housing 4 is rotatably connected to the rotating shaft 13. Vibration sensors 11 are arranged on the outer surface of the floating bearing housing 4. The lever arm 5 is rigidly connected to the floating bearing housing 4 to ensure the accuracy of the loading torque. One end of rotating shaft 14 and the other end of rotating shaft 2 are each connected to a clamp for holding the test shaft 2; The three-degree-of-freedom platform 12 includes an X-axis displacement mechanism 121, a Y-axis displacement mechanism 122, and a Z-axis rotation mechanism 123; Y-direction displacement mechanism 122 is arranged at the output end of X-direction displacement mechanism 121, where X-direction is the direction parallel to the axis of test axis 2. Z-axis rotation mechanism 123 is arranged at the output end of Y-axis displacement mechanism 122; The floating bearing housing 4 is arranged at the rotating end of the Z-axis rotating mechanism 123.
[0020] In this embodiment, the rotary drive motor 1 is used to transmit rotational power so that the test shaft 2 completes the 4-point bending durability test in a rotating state. The power of the rotary drive motor 1 passes through the coupling, shaft 14, test shaft 2, and shaft 2 13 in one go. The power transmission between shaft 14, shaft 2 13 and test shaft 2 is achieved by a fixture. If the two ends of the test shaft 2 are hollow, an internal support can be installed to avoid deformation during clamping and affect the entire test process. Fixed bearing housing 3 supports rotating shaft 14; The floating bearing seat 4 supports the rotating shaft 2 13. The three-degree-of-freedom platform 12 below the floating bearing seat 4 allows the floating bearing seat 4 to have the freedom of movement in the X direction, the Y direction, and the Z direction. This multi-degree-of-freedom floating structure can adapt to the deformation of the test shaft 2 during the test. It can adapt to the deformation displacement in the X direction, the deformation displacement in the Y direction, and the rotation angle change in the Z direction after the test shaft 2 is subjected to the loading force. Specifically, it can automatically adapt to the instantaneous position and attitude of the test shaft 2, and minimize the generation of external forces. This reduces interference forces and improves the accuracy of the four-point bending durability test. Secondly, this adaptive floating structure can also effectively reduce the vibration of the equipment during operation and improve the test safety. Vibration sensor 11 is used to monitor the vibration level during the test. Together with displacement sensor 6 in embodiment 1, it determines whether test shaft 2 has failed. If failure is detected, a stop command is triggered. When test shaft 2 fails, the vibration level (such as vibration amplitude) will rise sharply. In addition, when testing test shafts 2 of different lengths, the position of the floating bearing seat 4 in the X direction can be changed to meet the testing requirements of test shafts 2 of different lengths. exist Figure 4 In the test, the torque applied to test shaft 2 is 600, and the rotational speed of test shaft 2 is 1000. As time increases, The pink line indicates a sharp increase in the vibration level of floating bearing housing 4, rising from the range of 0.8 to 1 to around 1.5. The displacement fluctuation at the end of lever arm 5, represented by the purple line, has changed significantly; specifically, the fluctuation around 0.05 has intensified. At this point, test shaft 2 fails, triggering a stop command. The displacement of the end of lever arm 5 is reset to its initial position of approximately 0.38. Data can be read to obtain various data indicators of test shaft 2 during the 4-point bending durability test.
[0021] In some optional examples, the X-axis displacement mechanism 121 and the Y-axis displacement mechanism 122 are perpendicular to each other. The displacement of the X-axis displacement mechanism 121 and the Y-axis displacement mechanism 122 can be achieved by the structure of sliders and slide rails, and the rotation of the Z-axis rotation mechanism 123 is achieved by bearings.
[0022] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.
Claims
1. A rotary bending test device, characterized in that: Includes a lever arm (5) perpendicular to the axis of the test shaft (2), the lever arm (5) transmitting torque to the test shaft (2); The lever arm (5) is provided with a servo actuator (9) for applying push and pull force at one end away from the test shaft (2). The output shaft of the servo actuator (9) is connected to a force sensor (8). The other end of the force sensor (8) is connected to an elastic connector (7). The elastic connector (7) is connected to the lever arm (5). The direction of the output force of the servo actuator (9) is parallel to the axial direction of the test shaft (2).
2. The rotary bending test device according to claim 1, characterized in that: It includes a displacement sensor (6), which monitors the displacement change of the lever arm (5) on the side subjected to the action of the servo actuator (9).
3. The rotary bending test device according to claim 1, characterized in that: It also includes a floating bearing seat (4) that provides support to one end of the test shaft (2), and a three-degree-of-freedom platform (12) for supporting the floating bearing seat (4), the three-degree-of-freedom platform (12) having X-axis movement, Y-axis movement and Z-axis rotation.
4. The rotary bending test device according to claim 3, characterized in that: Including fixed bearing housing (3); The fixed bearing seat (3) is connected to the rotating shaft (14). The floating bearing seat (4) is connected to the rotating shaft (13). The opposite ends of the rotating shaft one (14) and rotating shaft two (13) are each connected to a clamp for holding the test shaft (2); The lever arm (5) is rigidly connected to the floating bearing seat (4).
5. A rotary bending test device according to claim 3 or 4, characterized in that: The three-degree-of-freedom platform (12) includes an X-axis displacement mechanism (121), a Y-axis displacement mechanism (122), and a Z-axis rotation mechanism (123). The floating bearing seat (4) is arranged at the rotating end of the Z-axis rotation mechanism (123), and the Z-axis rotation mechanism (123) is arranged on the cross slide formed by the X-axis displacement mechanism (121) and the Y-axis displacement mechanism (122).
6. A rotary bending test device according to claim 3 or 4, characterized in that: It also includes a vibration sensor (11) arranged on the floating bearing housing (4).
7. The rotary bending test device according to claim 4, characterized in that: It also includes a rotary drive motor (1), which is connected to a rotating shaft (14) via a coupling.
8. The rotary bending test device according to claim 1, characterized in that: It also includes a protective bracket (10) with a through hole, the inner diameter of which is larger than the diameter of the test shaft (2), and the through hole is used for the test shaft (2) to pass through.