Torsion tube bending fatigue test device and detection method thereof

Abstract

The present application belongs to the technical field of testing, and particularly relates to a torsion tube bending fatigue testing device and a detection method thereof. The torsion tube bending fatigue testing device comprises two clamping blocks slidingly arranged on a base, a bending driving member rotatably arranged on the base and used for driving the torsion tube to bend, and a bending guide assembly fixed to the end wall of the clamping block, wherein the bending guide assembly comprises a limiting block slidingly arranged in a guide column, and the end wall of the limiting block close to the torsion tube is provided with a thread matched with the outer wall of the torsion tube. When the bending driving member drives the torsion tube to bend, the outer wall of the torsion tube is in contact with a guide wheel and drives the guide wheel to rotate, the rotation of the guide wheel drives the limiting block to slide towards the torsion tube and abut against the outer wall of the torsion tube, the thread of the limiting block is engaged with the outer wall of the torsion tube to limit the circumferential rotation of the torsion tube, and the rotation of the guide wheel releases the frictional stress between the torsion tube and the bending guide assembly.

Description

Technical Field

[0001] This invention belongs to the field of testing technology, specifically relating to testing the strength characteristics of solid materials using mechanical stress, and particularly to a torsion tube bending fatigue testing device and its testing method. Background Technology

[0002] In the medical field, torsion tubes are core transmission components of equipment such as endoscopes, intravascular imaging catheters, and interventional surgical instruments. Bending fatigue testing of torsion tubes is a crucial step in ensuring the operational precision, clinical safety, and functional reliability of medical equipment; the test results directly impact patient safety and the success or failure of surgery.

[0003] Existing torsion tube bending fatigue testing devices typically employ the following structure:

[0004] Clamping and positioning: The outer wall of the fixed torsion tube is radially clamped by two clamping blocks that slide horizontally along the base, providing a stable reference for testing.

[0005] Bending drive: By applying a bending drive component fitted on the outer wall of the torsion tube, a periodic bending load is applied to simulate the stress cycle under actual working conditions.

[0006] Guide support: A bending stop is provided to guide the bending direction of the torsion tube and limit its displacement.

[0007] However, in practical applications, the existing technology has the following significant drawbacks:

[0008] Friction Interference Test Accuracy: When the torsion tube is driven by the bending drive component for bending fatigue testing, the outer wall of the torsion tube will experience severe sliding friction with the bending stop component. The additional stress generated by this friction will be superimposed on the test data, seriously interfering with the measurement of the true bending fatigue resistance of the torsion tube, resulting in distorted test results that cannot accurately reflect the actual performance of the product.

[0009] The testing process is unstable: When the bending drive component bends the torque tube, it generates a torsional torque, which can easily cause the torque tube to rotate relative to the two clamping blocks. This unexpected rotation changes the stress state of the torque tube, leading to unstable test conditions. This not only affects the consistency and repeatability of test data but may also cause additional damage to the torque tube and testing equipment.

[0010] Therefore, how to solve the problems of frictional interference and test instability in the existing technology is a technical problem that urgently needs to be solved in this field.

[0011] It should be noted that the information disclosed in this background section is only for understanding the background technology of this application concept, and therefore, the above description is not considered to constitute information related to the technology. Summary of the Invention

[0012] This disclosure provides at least one torsion tube bending fatigue testing device and its testing method.

[0013] In a first aspect, embodiments of this disclosure provide a torsion tube bending fatigue testing device, comprising:

[0014] The components include a base, two clamping blocks, a bending drive, and a bending guide assembly; the two clamping blocks are slidably disposed on the base for radially clamping the outer wall of the torsion tube.

[0015] The bending drive is rotatably mounted on the base and is used to drive the torque tube to bend; the bending guide assembly is fixed to the end wall of the clamping block and includes:

[0016] The guide post, guide wheel, and limiting block are provided. The guide wheel can rotate relative to the guide post. The limiting block is slidably disposed inside the guide post. The end wall of the limiting block near the torsion tube is provided with a thread that matches the outer wall of the torsion tube.

[0017] When the bending drive drives the torsion tube to bend, the outer wall of the torsion tube contacts the guide wheel and drives it to rotate. The rotation of the guide wheel drives the limiting block to slide towards the torsion tube and abut against the outer wall of the torsion tube. The thread of the limiting block is engaged with the outer wall of the torsion tube, restricting the circumferential rotation of the torsion tube. At the same time, the rotation of the guide wheel releases the frictional stress between the torsion tube and the bending guide assembly.

[0018] In one optional embodiment, the guide post has a groove formed radially, and the limiting block is slidably disposed within the groove;

[0019] An elastic reset component is also provided in the slide groove. The elastic reset component is used to drive the limiting block to separate from the outer wall of the torque tube after the guide wheel is reset and rotated.

[0020] In one optional embodiment, a notch is provided on the outer wall of the guide wheel, and one side wall of the notch abuts against the inner end wall of the limiting block. When the guide wheel rotates, the side wall of the notch pushes the limiting block to move radially outward.

[0021] In one optional embodiment, the outer surface of the guide wheel is provided with a wear-resistant layer, the material of which is polytetrafluoroethylene or self-lubricating ceramic.

[0022] In one alternative implementation, in the initial state, the side wall of the clamping block abuts against the outer wall of the torque tube, and a gap is left between the end wall of the limiting block and the outer wall of the torque tube.

[0023] In one optional embodiment, the bending drive includes a fixing ring sleeved on the outer wall of the torque tube and a drive block connected to the fixing ring. The drive block is fixed on a drive disk, and the drive disk is used to drive the fixing ring to reciprocate in a direction perpendicular to the axis of the torque tube.

[0024] In one optional embodiment, a pressure sensor is provided on the contact surface between the retaining ring and the torsion tube, the pressure sensor being used to detect the bending load applied by the retaining ring to the torsion tube in real time.

[0025] In one optional embodiment, both clamping blocks are provided with V-shaped positioning grooves that match the ends of the torque tubes, and anti-slip rubber pads are provided in the V-shaped positioning grooves.

[0026] In one optional embodiment, a linear guide rail is provided on the base, the two clamping blocks are slidably disposed on the linear guide rail, and an adjusting screw for driving the two clamping blocks to slide is also provided on the base.

[0027] Secondly, this disclosure also provides a detection method for a torsion tube bending fatigue testing device, comprising the following steps:

[0028] Step 1: Adjust the adjusting screw on the base to drive the two clamping blocks to slide along the linear guide to the preset position, place the outer wall of the torque tube in the V-shaped positioning groove of the clamping block, and clamp the torque tube radially.

[0029] Step 2: Start the control unit, set the bending frequency, bending amplitude and total fatigue test duration of the bending drive component, and the control unit drives the bending drive component to start working;

[0030] Step 3: The bending drive drives the torsion tube to bend periodically. During the bending process, the torsion tube contacts the guide wheel and drives the guide wheel to rotate. The guide wheel pushes the limiting block through the notch and slides along the groove towards the torsion tube until the thread on the end wall of the limiting block engages with the outer wall of the torsion tube, restricting the circumferential rotation of the torsion tube.

[0031] Step 4: The pressure sensor detects the bending load applied to the torsion tube by the bending drive in real time and feeds the load data back to the control unit. During the test, the appearance and structural integrity of the torsion tube are observed.

[0032] Step 5: After the preset test duration is reached, the control unit controls the bending drive to stop working, the guide wheel to reset and rotate, and the elastic reset component in the chute drives the limit block to slide away from the torque tube, so that the limit block separates from the torque tube.

[0033] Step 6: Loosen the clamping block, remove the torsion tube to be tested, and check whether the torsion tube shows fatigue failure phenomena such as micro-cracks, plastic deformation, and thread damage. Combine the load data of the pressure sensor to determine whether the bending fatigue performance of the torsion tube is qualified.

[0034] In one optional implementation, in step 4, if the bending load detected by the pressure sensor changes abruptly during the test, the control unit will automatically control the bending drive to stop working and issue an alarm to promptly terminate the continued testing of the failed torque tube.

[0035] The beneficial effects of this invention are that it provides a torsion tube bending fatigue testing device and method. By setting a guide wheel that can rotate relative to the guide column, the torsion tube makes rolling contact with the guide wheel instead of sliding contact during bending. Furthermore, the rotation of the guide wheel directly releases the frictional stress between the torsion tube and the bending guide assembly, avoiding the superposition of additional stress generated by friction into the test data. This ensures the accuracy of the measurement of the true bending fatigue resistance of the torsion tube, and the test results are more consistent with actual operating conditions. Further, the rotation of the guide wheel synchronously drives the limiting block to slide towards the torsion tube, and the thread on the end wall of the limiting block precisely engages with the outer wall of the torsion tube, forming a mechanical locking structure. This fundamentally restricts the circumferential rotation of the torsion tube during bending, avoiding unexpected changes in the stress state of the torsion tube, ensuring the consistency and repeatability of test conditions, and preventing additional damage to the equipment and specimen caused by the rotation of the torsion tube.

[0036] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description and the drawings.

[0037] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0039] Figure 1 A perspective view of the torsion tube bending fatigue testing device provided in an embodiment of this disclosure;

[0040] Figure 2A perspective view of the bending drive and guide post provided in an embodiment of this disclosure;

[0041] Figure 3 A perspective view of a bending guide assembly provided in an embodiment of this disclosure;

[0042] Figure 4 A cross-sectional perspective view of a bending guide assembly provided in an embodiment of this disclosure;

[0043] Figure 5 This is a schematic diagram of the state of the limiting block when the torsion tube is bent, as provided in an embodiment of this disclosure.

[0044] In the picture:

[0045] 1. Base; 11. Linear guide rail; 12. Adjusting screw;

[0046] 2. Clamping block;

[0047] 3. Bending guide assembly; 31. Guide post; 32. Limiting block; 33. Guide wheel; 34. Thread; 35. Slide groove; 36. Notch;

[0048] 4. Bending drive component; 41. Retaining ring; 42. Drive block; 43. Drive disc;

[0049] 5. Torque tube. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] In this document, when it is mentioned that a first component is located on a second component, this can mean that the first component can be directly formed on the second component, or that a third component can be inserted between the first and second components. Furthermore, in the accompanying drawings, the thickness of the components may be exaggerated or reduced for the purpose of effectively describing the technical content.

[0052] In this document, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. As used herein, expressions such as “at least one of…” modify an entire column of elements when following a column of elements. For example, the expression “at least one of a, b, and c” should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.

[0053] The terminology used herein is for the purpose of describing specific exemplary configurations only and is not intended to be limiting. As used herein, the singular articles “a,” “an,” and “the” may also be intended to include plural forms unless otherwise expressly stated herein. The terms “comprising,” “including,” and “having” are inclusive and thus specify the presence of features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein should not be construed as requiring them to be performed in the specific order discussed or shown, unless specifically identified as such. Additional or alternative steps may be employed.

[0054] As used herein, the phrases “in one embodiment,” “according to one embodiment,” “in some embodiments,” etc., generally refer to the fact that a particular feature, structure, or characteristic following the phrase can be included in at least one embodiment of this disclosure. Therefore, a particular feature, structure, or characteristic can be included in more than one embodiment of this disclosure, such that these phrases do not necessarily refer to the same embodiment. As used herein, the terms “example,” “exemplary,” etc., are used to “serve as an example, instance, or illustration.” Any implementation, aspect, or design described herein as “example” or “exemplary” is not necessarily to be construed as preferred or superior to other implementations, aspects, or designs. Rather, the use of the terms “example,” “exemplary,” etc., is intended to present concepts in a specific manner.

[0055] Research has shown that in the medical field, torsion tubes are core transmission components of equipment such as endoscopes, intravascular imaging catheters, and interventional surgical instruments. Bending fatigue testing of torsion tubes is a crucial step in ensuring the operational precision, clinical safety, and functional reliability of medical equipment; the test results directly impact patient safety and the success or failure of surgery.

[0056] Existing torsion tube bending fatigue testing devices typically employ the following structure:

[0057] Clamping and positioning: The outer wall of the fixed torsion tube is radially clamped by two clamping blocks that slide horizontally along the base, providing a stable reference for testing.

[0058] Bending drive: By applying a bending drive component fitted on the outer wall of the torsion tube, a periodic bending load is applied to simulate the stress cycle under actual working conditions.

[0059] Guide support: A bending stop is provided to guide the bending direction of the torsion tube and limit its displacement.

[0060] However, in practical applications, the existing technology has the following significant drawbacks:

[0061] Friction Interference Test Accuracy: When the torsion tube is driven by the bending drive component for bending fatigue testing, the outer wall of the torsion tube will experience severe sliding friction with the bending stop component. The additional stress generated by this friction will be superimposed on the test data, seriously interfering with the measurement of the true bending fatigue resistance of the torsion tube, resulting in distorted test results that cannot accurately reflect the actual performance of the product.

[0062] The testing process is unstable: When the bending drive component bends the torque tube, it generates a torsional torque, which can easily cause the torque tube to rotate relative to the two clamping blocks. This unexpected rotation changes the stress state of the torque tube, leading to unstable test conditions. This not only affects the consistency and repeatability of test data but may also cause additional damage to the torque tube and testing equipment.

[0063] Therefore, how to solve the problems of frictional interference and test instability in the existing technology is a technical problem that urgently needs to be solved in this field.

[0064] The defects in the above solutions and the reasons for their occurrence are the results of the inventors' practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed in this disclosure should be considered as the inventors' contributions to this disclosure.

[0065] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0066] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0067] like Figures 1 to 5 As shown, at least one embodiment provides a torsion tube bending fatigue testing device, including: a base 1, two clamping blocks 2, a bending drive component 4, and a bending guide assembly 3. The components work together to achieve clamping, bending drive, guiding friction reduction, and circumferential limiting of the torsion tube 5. The structure, connection relationship, and working principle of each component are described in detail below:

[0068] like Figure 2The base 1 serves as the overall support foundation for the device. It is integrally molded from high-strength alloy material to ensure structural stability during testing and prevent equipment displacement due to vibration or load impact. A linear guide rail 11 and an adjusting screw 12 are fixedly installed on the base 1. The linear guide rail 11 provides guidance for the sliding of the two clamping blocks 2. The adjusting screw 12 is threadedly connected to the two clamping blocks 2. One end of the adjusting screw 12 extends to the outside of the base 1 and is connected to an adjusting handwheel or a drive motor. The operator can drive the two clamping blocks 2 to slide towards or away from each other along the linear guide rail 11 by rotating the adjusting handwheel, thereby flexibly adjusting the distance between the two clamping blocks 2 to adapt to the clamping requirements of torque tubes 5 with different radial specifications.

[0069] Continue to refer to the appendix Figure 2 Two clamping blocks 2 are symmetrically slidably mounted on the linear guide rail 11 of the base 1. Their core function is to radially clamp and fix the outer walls of the torque tube 5 on both sides, providing a stable positioning reference for testing. A V-shaped positioning groove matching the outer wall of the end of the torque tube 5 is formed on the side of the clamping block 2 facing the torque tube 5. An anti-slip rubber pad is adhered to the inner wall of the V-shaped positioning groove. The anti-slip rubber pad is made of wear-resistant, high-friction coefficient silicone material, which can adapt to torque tubes 5 of different diameters, ensuring a close fit, and increasing the friction between the clamping block 2 and the torque tube 5, preventing axial slippage of the torque tube 5 during clamping, and avoiding physical damage such as indentations and scratches to the outer wall of the torque tube 5 caused by hard clamping. The end wall of the clamping block 2 is a planar structure, used to fix and connect the bending guide assembly 3, ensuring the connection stability between the bending guide assembly 3 and the clamping block 2, and keeping the relative position of the bending guide assembly 3 and the torque tube 5 fixed.

[0070] like Figure 3 The bending guide component 3 is the core innovative component of this invention. It is fixed to the end wall of the clamping block 2. Each clamping block 2 is provided with a set of bending guide components 3. The two sets of bending guide components 3 are symmetrically distributed at both ends of the torque tube 5 to realize three major functions: bending guidance of the torque tube, friction reduction by converting sliding friction to rolling friction, and synchronous driving circumferential limiting. The bending guide component 3 includes a guide post 31, a limiting block 32, and a guide wheel 33. The structure and cooperation relationship of each component are as follows:

[0071] like Figure 4The guide post 31 is a cylindrical metal structure. One outer wall of the guide post 31 is welded and fixed to the end wall of the clamping block 2. The axis of the guide post 31 is perpendicular to the axis of the torque tube 5. A sliding groove 35 is radially opened through the guide post 31. The sliding groove 35 is a rectangular through groove, and its extension direction coincides with the radial direction of the torque tube 5, providing guidance for the sliding of the limiting block 32. An elastic reset member is fixedly installed at one end of the sliding groove 35 away from the torque tube 5. In this embodiment, the elastic reset member is a compression spring. One end of the compression spring is welded and fixed to the inner wall of the sliding groove 35, and the other end abuts against the inner end wall of the limiting block 32, providing elastic driving force for the reset of the limiting block 32.

[0072] The limiting block 32 is a rectangular slider adapted to the slide groove 35. It is slidably embedded in the slide groove 35 and can slide horizontally radially towards or away from the torque tube 5 along the slide groove 35. The end wall of the limiting block 32 near the torque tube 5 is machined with a thread 34 that matches the outer wall of the torque tube 5. The pitch and tooth profile of the thread 34 are completely consistent with the thread on the outer wall of the torque tube 5 to ensure tight engagement. The inner end wall of the limiting block 32 is a planar structure, which abuts against the elastic reset member on one hand and cooperates with the notch side wall of the guide wheel 33 on the other hand to receive the pushing force of the guide wheel 33. In the initial state, under the pre-tightening force of the elastic reset member, a preset gap of 2-5mm is left between the end wall of the limiting block 32 and the outer wall of the torque tube 5 to avoid contact interference between the limiting block 32 and the torque tube 5 in the non-test state, and at the same time to reserve the sliding stroke of the limiting block 32.

[0073] exist Figure 5 In the diagram, F1 indicates the rotation direction of the guide wheel 33 when the torque tube 5 bends, and F2 indicates the movement direction of the notch wall pushing the limiting block 32. The guide wheel 33 is rotatably sleeved in the middle of the guide post 31, with its axis coinciding with the axis of the guide post 31. It can rotate circumferentially relative to the guide post 31 and is a core component for reducing friction. The outer surface of the guide wheel 33 is coated with a wear-resistant layer. In this embodiment, the wear-resistant layer is made of polytetrafluoroethylene or self-lubricating ceramic material. Both materials have low friction coefficients and high wear resistance, effectively reducing rolling wear between the guide wheel 33 and the torque tube 5 and extending the service life of the components. The outer wall of the guide wheel 33 has a notch 36 along the circumferential direction. The notch 36 is a rectangular notch, and one side wall is an inclined pushing surface. This pushing surface abuts against the inner end wall of the limiting block 32. When the guide wheel 33 rotates, the inclined pushing surface of the notch 36 will push the limiting block 32 in the horizontal direction, driving the limiting block 32 to overcome the preload of the elastic reset member and slide along the slide groove 35 towards the torque tube 5.

[0074] When the torsion tube 5 bends, it contacts the outer wall of the guide wheel 33, driving the guide wheel 33 to rotate relative to the guide post 31, converting the traditional sliding friction into rolling friction, and directly releasing the frictional stress between the torsion tube 5 and the bending guide assembly 3. At the same time, the rotation of the guide wheel 33 pushes the limiting block 32 to slide through the inclined pushing surface of the notch 36, so that the thread 34 on the end wall of the limiting block 32 engages with the outer wall of the torsion tube 5, forming a mechanical locking structure to restrict the circumferential rotation of the torsion tube 5. After the test, the guide wheel 33 resets and rotates, the pushing force of the notch 36 disappears, and the limiting block 32 slides away from the torsion tube 5 along the groove 35 under the driving force of the elastic reset component, separating from the outer wall of the torsion tube 5, and completing the reset.

[0075] like Figure 2 The bending drive 4 is rotatably positioned in the middle of the base 1, between the two sets of bending guide components 3. Its core function is to apply periodic bending loads to the torsion tube 5, simulating the bending conditions of the torsion tube 5 in actual use. It includes a fixed ring 41, a drive block 42, and a drive disc 43.

[0076] The fixing ring 41 is an open-type annular structure that is sleeved on the outer wall of the middle part of the torque tube 5. Its inner wall is in close contact with the outer wall of the torque tube 5 to transmit bending load to the torque tube 5. A pressure sensor is embedded on the contact surface between the fixing ring 41 and the torque tube 5. The pressure sensor is a high-precision miniature pressure sensor. Its detection end is in contact with the outer wall of the torque tube 5. It can detect the magnitude of the bending load applied to the torque tube 5 by the fixing ring 41 in real time and convert the load data into an electrical signal for external transmission.

[0077] The drive block 42 is a rigid connecting rod. One end of the drive block 42 is welded and fixed to the outer wall of the fixed ring 41, and the other end is rotatably connected to the eccentric position of the drive disk 43 to realize the power transmission between the drive disk 43 and the fixed ring 41.

[0078] The drive disk 43 is rotatably mounted on the base 1 and is connected to the output shaft of the servo motor. The servo motor provides controllable rotational power to the drive disk 43. When the drive disk 43 rotates around its own axis, the fixed ring 41 is driven to reciprocate in an arc shape along a direction perpendicular to the axis of the torque tube 5 through the eccentrically connected drive block 42, thereby driving the torque tube 5 to perform periodic bending deformation. The bending frequency and bending amplitude can be precisely adjusted by the servo motor to adapt to the test standard requirements of different torque tubes 5.

[0079] In this embodiment of the invention, the device is also equipped with a control unit, which is a PLC control cabinet with a touch screen display. The control unit is electrically connected to the servo motor of the bending drive component 4 and the pressure sensor, respectively. The core functions include setting test parameters, power drive control, load data acquisition and display, and abnormal alarm shutdown. The operator can set the bending frequency, bending amplitude and total fatigue test duration of the bending drive component 4 through the touch screen display. The control unit drives the servo motor to work according to the set parameters, and at the same time receives the load data of the pressure sensor in real time and displays it dynamically on the display screen. When the torque tube 5 fails due to fatigue during the test, the bending load will change abruptly. At this time, the control unit will automatically control the servo motor to stop working and issue an alarm prompt through the audible and visual alarm to terminate the test in time and avoid equipment damage and further failure of the test piece.

[0080] At least one embodiment provides a testing method for a torsion tube bending fatigue testing device, specifically including the following steps:

[0081] Step 1: Adjust the adjusting screw 12 on the base 1 to drive the two clamping blocks 2 to slide along the linear guide rail 11 to the preset position, place the outer wall of the torque tube 5 in the V-shaped positioning groove of the clamping block 2, and clamp the torque tube 5 radially.

[0082] Step 2: Start the control unit, set the bending frequency, bending amplitude and total fatigue test duration of the bending drive 4, and the control unit drives the bending drive 4 to start working;

[0083] Step 3: The bending drive 4 drives the torque tube 5 to bend periodically. During the bending process, the torque tube 5 contacts the guide wheel 33 and drives the guide wheel 33 to rotate. The guide wheel 33 pushes the limiting block 32 through the notch 36 and slides along the slide groove 35 toward the torque tube 5 until the thread 34 on the end wall of the limiting block 32 engages with the outer wall of the torque tube 5, restricting the circumferential rotation of the torque tube 5.

[0084] Step 4: The pressure sensor detects the bending load applied to the torsion tube 5 by the bending drive 4 in real time and feeds the load data back to the control unit. During the test, the appearance and structural integrity of the torsion tube 5 are observed.

[0085] Step 5: After the preset test duration is reached, the control unit controls the bending drive 4 to stop working, the guide wheel 33 resets and rotates, and the elastic reset component in the slide groove 35 drives the limit block 32 to slide away from the torque tube 5, so that the limit block 32 separates from the torque tube 5.

[0086] Step 6: Loosen clamping block 2, remove the torque tube 5 to be tested, and check whether the torque tube 5 has fatigue failure phenomena such as micro-cracks, plastic deformation, and damage to thread 34. Combine the load data of the pressure sensor to determine whether the bending fatigue performance of the torque tube 5 is qualified.

[0087] In step 4, if the bending load detected by the pressure sensor changes abruptly during the test, the control unit will automatically control the bending drive 4 to stop working and issue an alarm, thus terminating the continued testing of the failed torque tube 5 in a timely manner.

[0088] In this embodiment, the connection methods of each component adopt conventional mechanical methods such as welding, threaded connection, sliding fit, and rotational fit, which facilitates processing, assembly, and maintenance. All metal parts are treated with surface rust prevention to extend the overall service life of the device. The operation process of the device is simple and easy to understand. After simple training, the staff can complete the operation. It can be widely used in scenarios such as factory testing of medical equipment manufacturers, spot checks by quality supervision departments, and torque tube performance research of scientific research institutions.

[0089] It should be noted that the above embodiments of the present invention are merely illustrative examples and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adaptive adjustments to the material, specifications, and connection methods of the components based on the core technical solutions of the present invention. For example, the elastic reset component can be replaced by a spring sheet, rubber column, etc., instead of a compression spring; the wear-resistant layer of the guide wheel 33 can be replaced by other low-friction, high-wear-resistant materials; and the power source of the bending drive component 4 can be replaced by a stepper motor, etc. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0090] exist Figure 5 In the diagram, F1 indicates the rotation direction of the drive guide wheel when the torsion tube bends, and F2 indicates the movement direction of the limit block pushed by the notch wall.

[0091] In the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0092] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence unless expressly indicated herein. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or segment discussed above may be referred to as a second element, component, region, layer, or segment.

[0093] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A torsion tube bend fatigue testing apparatus characterized by, include: The base (1), two clamping blocks (2), a bending drive (4) and a bending guide assembly (3); the two clamping blocks (2) are slidably disposed on the base (1) for radially clamping the outer wall of the torsion tube (5); The bending drive (4) is rotatably mounted on the base (1) and is used to drive the torque tube (5) to bend; the bending guide assembly (3) is fixed to the end wall of the clamping block (2) and includes: The guide post (31), guide wheel (33) and limiting block (32) are provided. The guide wheel (33) can rotate relative to the guide post (31). The limiting block (32) is slidably disposed inside the guide post (31). The end wall of the limiting block (32) near the torsion tube (5) is provided with a thread (34) that matches the outer wall of the torsion tube (5). When the bending drive (4) drives the torsion tube (5) to bend, the outer wall of the torsion tube (5) contacts the guide wheel (33) and drives it to rotate. The rotation of the guide wheel (33) drives the limiting block (32) to slide towards the torque tube (5) and abut against the outer wall of the torque tube (5), and the thread (34) of the limiting block (32) engages with the outer wall of the torque tube (5) to restrict the circumferential rotation of the torque tube (5). At the same time, the rotation of the guide wheel (33) releases the frictional stress between the torque tube (5) and the bending guide assembly (3); The guide post (31) has a groove (35) in the radial direction, and the limiting block (32) is slidably disposed in the groove (35); An elastic reset member is also provided in the groove (35). The elastic reset member is used to drive the limiting block (32) to separate from the outer wall of the torque tube (5) after the guide wheel (33) is reset and rotated. The guide wheel (33) has a notch (36) on its outer wall. One side wall of the notch (36) abuts against the inner end wall of the limiting block (32). When the guide wheel (33) rotates, the side wall of the notch (36) pushes the limiting block (32) to move radially outward.

2. The torsion tube bending fatigue testing device as described in claim 1, characterized in that, The outer surface of the guide wheel (33) is provided with a wear-resistant layer, and the material of the wear-resistant layer is polytetrafluoroethylene or self-lubricating ceramic.

3. The torsion tube bending fatigue testing device as described in claim 1, characterized in that, In the initial state, the side wall of the clamping block (2) abuts against the outer wall of the torque tube (5), and the end wall of the limiting block (32) leaves a gap with the outer wall of the torque tube (5).

4. The torsion tube bending fatigue testing device as described in claim 1, characterized in that, The bending drive (4) includes a fixing ring (41) sleeved on the outer wall of the torque tube (5) and a drive block (42) connected to the fixing ring (41). The drive block (42) is fixed on the drive disk (43), which is used to drive the fixing ring (41) to reciprocate in a direction perpendicular to the axis of the torque tube (5).

5. The torsion tube bending fatigue testing device as described in claim 4, characterized in that, A pressure sensor is provided on the contact surface between the fixing ring (41) and the torsion tube (5). The pressure sensor is used to detect the bending load applied by the fixing ring (41) to the torsion tube (5) in real time.

6. The torsion tube bending fatigue testing device as described in claim 1, characterized in that, Both clamping blocks (2) are provided with V-shaped positioning grooves that match the end of the torque tube (5), and anti-slip rubber pads are provided in the V-shaped positioning grooves.

7. The torsion tube bending fatigue testing device as described in claim 1, characterized in that, A linear guide rail (11) is provided on the base (1), and the two clamping blocks (2) are slidably disposed on the linear guide rail (11). An adjusting screw (12) for driving the two clamping blocks (2) to slide is also provided on the base (1).

8. A detection method based on the torsion tube bending fatigue test device according to any one of claims 1 to 7, characterized by, Includes the following steps: Step 1: Adjust the adjusting screw (12) on the base (1) to drive the two clamping blocks (2) to slide along the linear guide rail (11) to the preset position, place the outer wall of the torque tube (5) in the V-shaped positioning groove of the clamping block (2), and clamp the torque tube (5) from the radial direction. Step 2: Start the control unit, set the bending frequency, bending amplitude and total fatigue test duration of the bending drive (4), and the control unit drives the bending drive (4) to start working; Step 3: The bending drive (4) drives the torsion tube (5) to bend periodically. During the bending process, the torsion tube (5) contacts the guide wheel (33) and drives the guide wheel (33) to rotate. The guide wheel (33) pushes the limiting block (32) through the notch (36) and slides along the slide groove (35) toward the torsion tube (5) until the thread (34) on the end wall of the limiting block (32) engages with the outer wall of the torsion tube (5) to restrict the circumferential rotation of the torsion tube (5). Step 4: The pressure sensor detects the bending load applied to the torsion tube (5) by the bending drive (4) in real time and feeds the load data back to the control unit. During the test, the appearance and structural integrity of the torsion tube (5) are observed. Step 5: After the preset test duration is reached, the control unit controls the bending drive (4) to stop working, the guide wheel (33) resets and rotates, and the elastic reset component in the slide groove (35) drives the limit block (32) to slide away from the torque tube (5), so that the limit block (32) separates from the torque tube (5). Step 6: Loosen the clamping block (2), remove the torsion tube (5) to be tested, and check whether the torsion tube (5) has fatigue failure phenomena such as microcracks, plastic deformation, and thread damage. Combine the load data of the pressure sensor to determine whether the bending fatigue performance of the torsion tube (5) is qualified.

9. The detection method of the torsion tube bending fatigue testing device as described in claim 8, characterized in that, In step 4, if the bending load detected by the pressure sensor changes abruptly during the test, the control unit will automatically control the bending drive (4) to stop working and issue an alarm prompt to terminate the continued test of the failed torque tube (5) in a timely manner.

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