A device for torsional fatigue testing of steel cord

Abstract

The present invention relates to the technical field of metal wire performance detection, and specifically to a device for torsional fatigue testing of steel cords, comprising a frame, a slide rail is arranged on the frame, a fixed clamp and a movable clamp are slidably mounted on the slide rail, the fixed clamp and the movable clamp both comprise a coaxially arranged chuck seat and an outer cylinder, the chuck seat is provided with a plurality of limiting slide grooves extending radially along the chuck seat, a fan-shaped clamp block is slidably mounted in the limiting slide groove, an adjusting sleeve is coaxially arranged in the outer cylinder, and a first rotating driver is arranged on the frame. The technical scheme uses the adjusting sleeve to enable the fan-shaped clamp block to synchronously move along the limiting slide groove to center and clamp the steel cord, thereby improving the clamping stability when the steel cord is twisted, the first rotating driver drives the chuck seat of the movable clamp to rotate around its own axis, and the steel cord is twisted around its own axis, thereby preventing the steel cord from deflecting during the test and thus affecting the influence of the torsional force on the steel cord.

Description

Technical Field

[0001] The invention relates to the technical field of metal wire performance detection, and in particular to a device for torsional fatigue testing of steel cords. Background Art

[0002] Torsion fatigue is one of the important parameters for fatigue resistance of metal wire. The current torsion fatigue testing machine has a pair of clamps installed on the same axis, in which the rotating clamp can rotate around the axis of the sample, and the fixed clamp does not rotate at all, but can move freely in the axial direction. The frame is equipped with a scale to measure the length of the gauge between the two clamps. When performing a torsion fatigue test, the sample is clamped flatly between the two clamps, and the rotating clamp rotates to drive the sample to twist around its own axis until the sample breaks.

[0003] Existing clamps usually clamp the metal wire with double-sided clamping, which is prone to slippage during rotation, thus affecting the test results. Double-sided clamping cannot ensure that the clamped metal wire maintains the axial twist during twisting. The metal wire will deviate in direction during twisting, thus affecting the test results. Summary of the invention

[0004] In view of the above problems, it is necessary to provide a device for torsional fatigue testing of steel cords to address the problems of the prior art.

[0005] In order to solve the problems of the prior art, the technical solution adopted by the present invention is:

[0006] A device for torsional fatigue testing of steel cords comprises a frame, a slide rail is arranged on the frame, a fixed clamp and a movable clamp are slidably mounted on the slide rail, the fixed clamp and the movable clamp both comprise a coaxially arranged chuck seat and an outer cylinder, through holes for passing the steel cord are arranged at the axes of the chuck seat and the outer cylinder; a plurality of limiting slide grooves extending radially along the chuck seat are arranged in the chuck seat, a fan-shaped clamp block is slidably mounted in the limiting slide groove, each fan-shaped clamp block is provided with a tapered end at one end close to the outer cylinder, the tapered end has a gradually reduced taper, an adjusting sleeve is coaxially arranged in the outer cylinder, and the adjusting sleeve is pressed toward a pressing sleeve head arranged at one end of the chuck seat to fit the tapered shape of the fan-shaped clamp block The outer wall of the end, the adjusting sleeve moves along the axis toward the fan-shaped clamping block so that the fan-shaped clamping block moves synchronously along the limiting slide groove to center and clamp the steel cord; the frame is provided with a first rotating driver for driving the chuck seat of the mobile clamp to rotate around its own axis; the outer wall of the adjusting sleeve is provided with a first tooth groove arranged along the axis direction of the adjusting sleeve, the inner wall of the outer cylinder is provided with a second tooth groove arranged along the axis direction of the outer cylinder, a bracket is provided on the chuck seat, a gear is rotatably installed on the bracket, the axis of the gear is perpendicular to the axis of the chuck seat, the first tooth groove of the adjusting sleeve and the second tooth groove of the outer cylinder are respectively meshed and connected with the gear; the frame is provided with a linear driving unit for driving the outer cylinder to move along its own axis direction.

[0007] Preferably, the linear drive unit includes a second rotation driver fixedly mounted on one end of the frame, the working end of the second rotation driver is coaxially connected to the threaded rod, and the frame is provided with parallel first guide rods on both sides of the threaded rod, and the threaded rod and the first guide rod extend along the length direction of the slide rail; the outer cylinder is rotatably mounted on a movable seat, and the movable seat is provided with a threaded sleeve which is in the same straight line as the threaded rod, and a first guide hole which is in the same straight line as the first guide rod, the threaded rod is spirally inserted in the threaded sleeve, and the first guide rod is respectively inserted in the first guide hole; a positioning seat is also provided on the slide rail, and the chuck seat in the movable clamp is rotatably mounted in a first mounting frame provided on the positioning seat.

[0008] Preferably, a limiter is provided in the slide rail for positioning the positioning seat.

[0009] Preferably, the outer wall of the adjusting sleeve is provided with a plurality of limit slots extending along the axis of the adjusting sleeve; the inner wall of the outer cylinder is provided with clamping strips having the same number as the limit slots, and the clamping strips are inserted into the limit slots of the adjusting sleeve.

[0010] Preferably, the outer cylinder is provided with a plurality of limit blocks at one end facing the chuck seat, the limit blocks are surrounded by the circumference of the adjustment sleeve, and a second guide hole parallel to the axis of the outer cylinder is provided on the limit block; the chuck seat is provided with a plurality of second guide rods which are in the same straight line as the second guide holes at one end facing the outer cylinder, the second guide rods are inserted in the second guide holes and extend to the inside of the outer cylinder, a limit head is provided at one end of the second guide rod located inside the outer cylinder, a spring is sleeved on the second guide rod, the spring elastically connects the limit head and the limit block, and the elastic force of the spring causes the outer cylinder to move toward the chuck seat.

[0011] Preferably, a push plate protruding from the surface of the fan-shaped clamp block is provided at one end of each fan-shaped clamp block away from the axis of the chuck seat, and a return spring is provided in each limiting slide groove. The return spring elastically connects the end of the limiting slide groove close to the axis and the push plate on the fan-shaped clamp block, and the elastic force of the return spring makes the fan-shaped clamp block move away from the axis of the chuck seat.

[0012] Preferably, a first synchronous wheel is coaxially arranged on the outside of the chuck seat of the movable clamp, the first synchronous wheel is connected to the second synchronous wheel through a synchronous belt transmission, the second synchronous wheel is rotatably mounted in a second mounting frame arranged on the positioning seat, and a spline groove is arranged at the axis of the second synchronous wheel; the first rotary driver is fixedly mounted on one end of the frame, the working end of the first rotary driver is transmission-connected to the spline shaft, the spline shaft extends along the length direction of the slide rail, and the second synchronous wheel is spline-connected to the spline shaft through the spline groove.

[0013] Preferably, the chuck seat of the fixing clamp is fixedly mounted on the positioning seat; and the first mounting frame of the chuck seat and the movable seat of the outer cylinder are both provided with avoidance holes for avoiding the spline shaft.

[0014] Preferably, a notch for avoiding the threaded rod is provided on the movable seat of the outer cylinder of the fixed clamp, and distance-adjusting threaded rods extending toward one side of the fixed clamp along the length direction of the slide rail are provided on both sides of the movable seat of the movable clamp, and the distance-adjusting threaded rods are inserted into the mounting ears provided on both sides of the movable seat of the fixed clamp, and a locking nut is spirally installed on the distance-adjusting threaded rod, and the locking nut fixes the distance between the movable seat of the fixed clamp and the movable clamp.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] Firstly, the fan-shaped clamp in the present invention is located on the circumferential side of the steel cord to center and clamp the steel cord. The more contact points between the fan-shaped clamp and the circumferential side of the steel cord, the higher the clamping stability when the steel cord is twisted. After clamping is completed, the steel cord clamped by the fixed clamp and the movable clamp is in the axial position of the fixed clamp and the movable clamp. When the first rotary drive drives the clamp head seat of the movable clamp to rotate around its own axis, the steel cord is twisted around its own axis, thereby avoiding deflection of the steel cord during the test and affecting the influence of the torsional force on the steel cord, thereby ensuring the accuracy of the test results.

[0017] Secondly, the chuck seat in the present invention is rotatably installed in the first mounting frame of the positioning seat, and the outer cylinder is rotatably installed on the moving seat, so that the chuck seat and the outer cylinder are kept in the same straight line. When the linear drive unit drives the outer cylinder away from the chuck seat, the position of the positioning seat is fixed to keep the position of the chuck seat fixed, which not only ensures the stability of the limiting slide groove when the pressing sleeve pushes the fan-shaped clamp block to move, but also ensures that the fan-shaped clamp block only applies radial clamping force to the steel cord, and will not pull the straightened steel cord, thereby affecting the accuracy of the torsional fatigue test.

[0018] Thirdly, the fixed clamp and the movable clamp in the present invention are slidably installed on the slide rail of the frame, so the distance between the fixed clamp and the movable clamp can be changed, the clamp seat of the movable clamp is transmission-connected to the second synchronous wheel, and the second synchronous wheel is slidably installed on the spline shaft through the spline groove, so that the clamp seat of the movable clamp can be rotated at any position, and the torsion test of steel cords of different lengths can be performed, and the outer cylinders of the fixed clamp and the movable clamp are connected by adjusting the distance threaded rod, the mounting ear and the locking nut, so as to ensure that the outer cylinders of the fixed clamp and the movable clamp can be moved synchronously at any position, and the steel cord is clamped synchronously and the clamping force is kept the same. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a stereoscopic view of a device for torsional fatigue testing of steel cords in a non-operating state;

[0020] Figure 2 It is a top view of a device for torsional fatigue testing of steel cords in a non-working state;

[0021] Figure 3 yes Figure 2 A cross-sectional view at AA of FIG.

[0022] Figure 4 yes Figure 3 A partial enlarged view of point B;

[0023] Figure 5 It is a stereoscopic diagram of a device for torsional fatigue testing of steel cords in working condition;

[0024] Figure 6 It is a top view of a device for torsional fatigue testing of steel cords in working condition;

[0025] Figure 7 yes Figure 6 A cross-sectional view of the section at CC;

[0026] Figure 8 yes Figure 7 A partial enlarged view of point D;

[0027] Fig. 9 It is a three-dimensional structural exploded diagram of a device used for torsional fatigue testing of steel cords;

[0028] Fig.10 yes Fig. 9 A local enlarged view of point E;

[0029] Fig.11 yes Fig. 9 A partial enlarged view of point F.

[0030] The numbers in the figure are: 1, frame; 11, slide rail; 111, stopper; 12, fixed clamp; 13, mobile clamp; 14, first rotary driver; 141, spline shaft; 15, linear drive unit; 151, second rotary driver; 152, threaded rod; 153, first guide rod; 2, chuck seat; 21, limit slide; 211, fan-shaped clamp block; 212, tapered end; 213, push plate; 214, return spring; 22, bracket; 221, gear; 23, positioning seat; 231, first mounting bracket; 232, second mounting bracket; 24, second guide rod; 241, limit head; 242, spring; 25, first synchronous wheel; 251, synchronous belt; 252, second synchronous wheel; 3. Outer cylinder; 31. Adjusting sleeve; 311. Pressing sleeve head; 312. First tooth groove; 313. Limiting slot; 32. Second tooth groove; 33. Moving seat; 332. First guide hole; 333. Adjusting threaded rod; 334. Mounting ear; 335. Locking nut; 34. Clip strip; 35. Limiting block; 351. Second guide hole. DETAILED DESCRIPTION

[0031] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0032] Reference Figures 1 to 11 :

[0033] A device for torsional fatigue testing of steel cords comprises a frame 1, a slide rail 11 is arranged on the frame 1, a fixed clamp 12 and a movable clamp 13 are slidably mounted on the slide rail 11, the fixed clamp 12 and the movable clamp 13 both comprise a coaxially arranged chuck seat 2 and an outer cylinder 3, through holes for passing the steel cord are arranged at the axes of the chuck seat 2 and the outer cylinder 3; a plurality of limiting slide grooves 21 extending radially along the chuck seat 2 are arranged in the chuck seat 2, a sector-shaped clamp block 211 is slidably mounted in the limiting slide groove 21, and each sector-shaped clamp block 211 is provided with a tapered end 212 at one end close to the outer cylinder 3, and the tapered end 212 is provided at the end of the tapered end 212. The conical end 212 has a gradually decreasing taper, and an adjusting sleeve 31 is coaxially arranged in the outer cylinder 3. The adjusting sleeve 31 is arranged toward a pressing sleeve head 311 arranged at one end of the chuck seat 2 to fit the outer wall of the conical end 212 of the sector-shaped clamping block 211, and the adjusting sleeve 31 moves along the axis toward the sector-shaped clamping block 211 so that the sector-shaped clamping block 211 moves synchronously along the limiting slide groove 21 to center and clamp the steel cord; a first rotating driver 14 is arranged on the frame 1 to drive the chuck seat 2 of the moving clamp 13 to rotate around its own axis; the outer wall of the adjusting sleeve 31 is provided with a first tooth groove 312 (such as Fig.11 As shown in the figure, the inner wall of the outer cylinder 3 is provided with a second tooth groove 32 arranged along the axial direction of the outer cylinder 3, a bracket 22 is provided on the chuck seat 2, a gear 221 is rotatably mounted on the bracket 22, the axis of the gear 221 is perpendicular to the axis of the chuck seat 2, the first tooth groove 312 of the adjusting sleeve 31 and the second tooth groove 32 of the outer cylinder 3 are respectively meshed and connected with the gear 221; a linear driving unit 15 for driving the outer cylinder 3 to move along its own axial direction is provided on the frame 1.

[0034] The linear drive unit 15 includes a second rotary driver 151 fixedly mounted at one end of the frame 1. The working end of the second rotary driver 151 is coaxially connected to a threaded rod 152. The frame 1 is provided with parallel first guide rods 153 on both sides of the threaded rod 152. The threaded rod 152 and the first guide rod 153 extend along the length direction of the slide rail 11. The outer cylinder 3 is rotatably mounted on the moving seat 33 (such as Figure 8 As shown in the figure, the movable seat 33 is provided with a threaded sleeve which is in the same straight line as the threaded rod 152, and a first guide hole 332 which is in the same straight line as the first guide rod 153, the threaded rod 152 is screwed into the threaded sleeve, and the first guide rod 153 is respectively inserted into the first guide hole 332; a positioning seat 23 is also provided on the slide rail 11, and the chuck seat 2 in the movable clamp 13 is rotatably mounted in the first mounting frame 231 provided on the positioning seat 23.

[0035] When the torsional fatigue testing device in the present application is in use, the staff straightens the steel cord and passes it through the through hole at the axis of the chuck seat 2 and the outer cylinder 3 of the fixed clamp 12 and the movable clamp 13. The chuck seat 2 of the fixed clamp 12 and the movable clamp 13 is provided with a limiting slide groove 21 extending radially along the chuck seat 2. The fan-shaped clamp block 211 in each limiting slide groove 21 can move along the limiting slide groove 21. When the adjusting sleeve 31 of the outer cylinder 3 moves toward one end of the chuck seat 2, the pressing sleeve head 311 of the adjusting sleeve 31 fits the outer wall of the tapered end 212 of the fan-shaped clamp block 211. The pressing sleeve head 311 squeezes the fan-shaped clamp block 211 toward the axis of the chuck seat 2. The fan-shaped clamp block 211 moves synchronously in the limiting slide groove 21, thereby centering the steel cord passing through the chuck seat 2 In this embodiment, there are four fan-shaped clamps 211. The actual number of fan-shaped clamps 211 can be designed according to the needs. The more fan-shaped clamps 211 there are, the more contact points there are between the clamp seat 2 and the circumference of the steel cord, so that the clamping stability is higher when the steel cord is twisted, and the fan-shaped clamps 211 clamp the steel cord in the center, so after the clamping is completed, the steel cord clamped by the fixed clamp 12 and the movable clamp 13 is at the axis position of the fixed clamp 12 and the movable clamp 13. When the first rotary driver 14 drives the clamp seat 2 of the movable clamp 13 to rotate around its own axis, the steel cord is twisted around its own axis, so that the steel cord is prevented from deflecting during the test, thereby affecting the influence of the torsional force on the steel cord, and ensuring the accuracy of the test results. The fixed clamp 12 and the movable clamp 13 in this embodiment are slidably mounted on the slide rail 11 of the frame 1, so the distance between the fixed clamp 12 and the movable clamp 13 can be changed, so as to achieve torsion testing of steel cords of different lengths.

[0036] In this embodiment, the frame 1 is provided with a linear drive unit 15 for driving the outer cylinder 3 to move horizontally in the axial direction. The linear drive unit 15 cooperates with the moving seat 33 to form a screw slide structure through the second rotary drive 151, the threaded rod 152 and the first guide rod 153. When the second rotary drive 151 drives the threaded rod 152 to rotate, the threaded sleeve in the moving seat 33 can be driven to move along the threaded rod 152, so that the moving seat 33 drives the outer cylinder 3 to move along the axis of the threaded rod 152. When the moving seat 33 drives the outer cylinder 3 away from the chuck seat 2, the inner wall of the outer cylinder 3 The second tooth groove 32 is meshed with the gear 221 rotatably installed on the bracket 22 of the chuck seat 2. The movement of the outer cylinder 3 can drive the gear 221 to rotate. The gear 221 is also meshed with the first tooth groove 312 on the outer wall of the adjusting sleeve 31, thereby driving the adjusting sleeve 31 to move in the opposite direction and close to the chuck seat 2 in the process of the outer cylinder 3 moving away from the chuck seat 2. In the process of the adjusting sleeve 31 moving toward the chuck seat 2, the sleeve head 311 is pressed to fit the conical end 212 of the fan-shaped clamping block 211, thereby clamping the steel cord. The second rotation driver 151 in this embodiment can be a servo motor. The chuck seat 2 in this embodiment is rotatably installed in the first mounting frame 231 of the positioning seat 23, and the outer cylinder 3 is rotatably installed on the movable seat 33, so as to keep the chuck seat 2 and the outer cylinder 3 in the same straight line. When the linear drive unit 15 drives the outer cylinder 3 away from the chuck seat 2, the position of the positioning seat 23 is fixed to keep the position of the chuck seat 2 fixed, which not only ensures the stability of the limiting slide groove 21 when the pressing sleeve 311 pushes the fan-shaped clamping block 211 to move, but also ensures that the fan-shaped clamping block 211 only applies a radial clamping force to the steel cord, and will not pull the straightened steel cord, thereby affecting the accuracy of the torsional fatigue test.

[0037] In order to lock the distance between the clamping points of the fixed clamp 12 and the movable clamp 13 on the steel cord, the following features are specifically set:

[0038] A stopper 111 for positioning the positioning seat 23 is disposed in the slide rail 11 .

[0039] In this embodiment, a stopper 111 is provided in the slide rail 11. After moving the clamping seat 2 of the fixed clamp 12 and the movable clamp 13, the staff can fix the stopper 111 on both sides of the positioning seat 23 of the clamping seat 2 to lock the position of the clamping seat 2 of the fixed clamp 12 and the movable clamp 13, so as to ensure that the spacing between the clamping points of the steel cord is fixed, and to achieve the torsional fatigue test of different clamping spacings of the steel cord. The stopper 111 can be installed on the slide rail 11 by bolts, or it can be realized by other existing technologies.

[0040] In order to solve the problem of how to ensure that the second tooth groove 32 is located at the axis of the outer cylinder 3 and maintain the stability of the meshing connection state between the first tooth groove 312 and the second tooth groove 32 and the gear 221, the following features are specifically set:

[0041] The outer wall of the adjusting sleeve 31 is provided with a plurality of limit slots 313 extending along the axis of the adjusting sleeve 31 ; the inner wall of the outer cylinder 3 is provided with the same number of clamping strips 34 as the limit slots 313 , and the clamping strips 34 are inserted into the limit slots 313 of the adjusting sleeve 31 .

[0042] In this embodiment, the inner wall of the outer cylinder 3 is provided with a plurality of clamping strips 34, which are inserted into the limiting clamping grooves 313 provided on the outer wall of the adjusting sleeve 31 at various angles around the adjusting sleeve 31, so as to stabilize the adjusting sleeve 31 at the axial position of the outer cylinder 3 and lock the relative angle between the outer cylinder 3 and the adjusting sleeve 31, so as to ensure that the adjusting sleeve 31 and the outer cylinder 3 do not rotate relative to each other, thereby ensuring that the second tooth groove 32 of the outer cylinder 3 and the first tooth groove 312 of the adjusting sleeve 31 always maintain a relative and parallel state.

[0043] The second tooth groove 32 and the first tooth groove 312 are kept parallel and at a constant distance. However, during the torsion test, the chuck seat 2 will rotate while clamping the steel cord. In order to ensure that the first tooth groove 312 and the second tooth groove 32 of the outer cylinder 3 always maintain a meshing connection state with the gear 221 when the chuck seat 2 rotates, the following features are specifically set:

[0044] The end of the outer cylinder 3 facing the chuck seat 2 is provided with a plurality of limit blocks 35, the limit blocks 35 surround the circumference of the adjustment sleeve 31, and the limit blocks 35 are provided with a second guide hole 351 parallel to the axis of the outer cylinder 3; the end of the chuck seat 2 facing the outer cylinder 3 is provided with a plurality of second guide rods 24 which are in the same straight line as the second guide holes 351, the second guide rods 24 are inserted in the second guide holes 351 and extend to the inside of the outer cylinder 3, and a limit head 241 is provided at one end of the second guide rod 24 located inside the outer cylinder 3, and a spring 242 is sleeved on the second guide rod 24, the spring 242 elastically connects the limit head 241 and the limit block 35, and the elastic force of the spring 242 causes the outer cylinder 3 to move toward the chuck seat 2.

[0045] The plurality of second guide rods 24 of the chuck seat 2 are inserted into the second guide holes 351 of the limit block 35 provided on the outer cylinder 3. Therefore, when the chuck seat 2 rotates, the outer cylinder 3 rotates synchronously with the chuck seat 2, thereby maintaining the meshing connection state between the first tooth groove 312 and the second tooth groove 32 and the gear 221. The spring 242 on the second guide rod 24 applies the elastic force of the limit block 35 to move the outer cylinder 3 toward the chuck seat 2 and make the outer cylinder 3 and the chuck seat 2 fit together. Therefore, the limit block on the slide rail 11 After the device 111 releases the limit on the positioning seat 23, the linear drive unit 15 drives the moving seat 33 to move, which can drive the chuck seat 2 and the outer cylinder 3 of the mobile clamp 13 to move synchronously, changing the position of the mobile clamp 13 on the slide rail 11, thereby changing the distance between the clamping points of the steel cord during the test. During the movement, the relative positions of the positioning seat 23 and the mobile seat 33 are fixed, so the fan-shaped clamp block 211 will not clamp the steel cord in the chuck seat 2, thereby affecting the movement of the mobile clamp 13.

[0046] When the outer cylinder 3 moves toward the clamping head seat 2, the adjusting sleeve 31 moves in the opposite direction away from the fan-shaped clamping block 211, so the pressing sleeve head 311 releases the pressing of the tapered end 212 of the fan-shaped clamping block 211. In order to enable the fan-shaped clamping block 211 to automatically reset and release the clamping of the steel cord, the following features are specifically provided:

[0047] A push plate 213 protruding from the surface of the fan-shaped clamp block 211 is provided at one end of each fan-shaped clamp block 211 away from the axis of the chuck seat 2, and a return spring 214 is provided in each limiting slide groove 21. The return spring 214 elastically connects the end of the limiting slide groove 21 close to the axis and the push plate 213 on the fan-shaped clamp block 211. The elastic force of the return spring 214 makes the fan-shaped clamp block 211 away from the axis of the chuck seat 2.

[0048] The limiting slot 21 in this embodiment is also provided with a return spring 214, which applies an elastic force to the push plate 213 at the end of the fan-shaped clamp 211 away from the axis of the chuck seat 2, so that the fan-shaped clamp 211 moves along the limiting slot 21 to the end away from the axis of the chuck seat 2. When the pressing sleeve head 311 is in contact with the tapered end 212 of the fan-shaped clamp 211 to press the fan-shaped clamp 211 to move toward the axis of the chuck seat 2, the return spring 214 is compressed by the push plate 213. When the adjusting sleeve 31 is reset, the fan-shaped clamp 211 is only subjected to the elastic force of the return spring 214, so it can drive the fan-shaped clamp 211 to move to the end of the limiting slot 21 away from the axis of the chuck seat 2, and automatically release the clamping of the steel cord.

[0049] In order to solve the problem of how the first rotary driver 14 drives the clamping head seat 2 of the movable clamp 13 to rotate when it moves to various positions, the following features are specifically provided:

[0050] A first synchronous wheel 25 is coaxially arranged on the outside of the chuck seat 2 of the movable clamp 13, and the first synchronous wheel 25 is connected to the second synchronous wheel 252 through a synchronous belt 251. The second synchronous wheel 252 is rotatably mounted in a second mounting frame 232 arranged on the positioning seat 23, and a spline groove is arranged at the axis of the second synchronous wheel 252; the first rotary driver 14 is fixedly mounted at one end of the frame 1, and the working end of the first rotary driver 14 is connected to the spline shaft 141 through a spline groove. The spline shaft 141 extends along the length direction of the slide rail 11, and the second synchronous wheel 252 is spline-connected to the spline shaft 141 through a spline groove.

[0051] The first rotary driver 14 in the present embodiment is transmission connected with the spline shaft 141 rotatably mounted on the frame 1. The first rotary driver 14 can be a servo motor. The first synchronous wheel 25 is coaxially arranged outside the chuck seat 2 of the mobile clamp 13. The second synchronous wheel 252 is rotatably mounted on the second mounting frame 232 of the positioning seat 23. The second synchronous wheel 252 is mounted on the spline shaft 141 through the spline groove at the axis. Therefore, when the mobile clamp 13 moves along the slide rail 11, the second synchronous wheel 252 moves along the spline shaft 141. The second synchronous wheel 252 can rotate with the spline shaft 141 at any position, thereby transmitting the first synchronous wheel 25 through the synchronous belt 251, driving the chuck seat 2 to rotate, and twisting the steel cord clamped by the fan-shaped clamp block 211 of the chuck seat 2.

[0052] In order to ensure that the clamping head seat 2 of the fixing clamp 12 clamps one end of the steel cord stably, the following features are specifically provided:

[0053] The chuck seat 2 of the fixed clamp 12 is fixedly mounted on the positioning seat 23 ; the first mounting frame 231 of the chuck seat 2 and the moving seat 33 of the outer cylinder 3 are both provided with avoidance holes for avoiding the spline shaft 141 .

[0054] The chuck seat 2 of the fixed clamp 12 in this embodiment is fixedly installed on the positioning seat 23 and cannot rotate. Therefore, when the chuck seat 2 of the movable clamp 13 clamps the steel cord and rotates, the fixed clamp 12 clamps one end of the steel cord and remains stable. The first mounting frame 231 of the chuck seat 2 and the movable seat 33 of the outer tube 3 are provided with avoidance holes for avoiding the spline shaft 141, so that the rotation of the spline shaft 141 can drive the chuck seat 2 of the movable clamp 13 to rotate as much as possible.

[0055] In order to achieve the purpose of clamping the steel cord by the fixed clamp 12 and the movable clamp 13 at the same time and maintaining the same clamping force, the following features are specifically set:

[0056] A notch for avoiding the threaded rod 152 is provided on the movable seat 33 of the outer cylinder 3 of the fixed clamp 12, and distance-adjusting threaded rods 333 extending toward one side of the fixed clamp 12 along the length direction of the slide rail 11 are provided on both sides of the movable seat 33 of the movable clamp 13. The distance-adjusting threaded rods 333 are inserted into the mounting ears 334 provided on both sides of the movable seat 33 of the fixed clamp 12, and a locking nut 335 is spirally installed on the distance-adjusting threaded rod 333, which fixes the distance between the movable seat 33 of the fixed clamp 12 and the movable clamp 13.

[0057] In this embodiment, a notch is provided on the fixed clamp 12 to avoid the threaded rod 152. Therefore, when the second rotation driver 151 drives the threaded rod 152 to rotate, the outer tube 3 of the fixed clamp 12 will not move, and the position of the steel cord clamped by the fixed clamp 12 is kept fixed. When the mobile clamp 13 is moved before the test, the staff removes the locking nut 335 on the pitch-adjusting threaded rod 333. When the mobile clamp 13 moves, the pitch-adjusting threaded rod 333 moves in the installation ear 334 on the outer tube 3 of the fixed clamp 12. When the position of the mobile clamp 13 is determined, the staff re-engages the clamp 13. A new locking nut 335 is installed. After locking the locking nut 335, the distance between the outer cylinders 3 on the fixed clamp 12 and the movable clamp 13 can be locked. When the linear drive unit 15 drives the outer cylinder 3 of the movable clamp 13 to move, the outer cylinder 3 of the fixed clamp 12 moves synchronously, so that the fixed clamp 12 and the movable clamp 13 clamp the steel cord synchronously. The moving distances of the outer cylinders 3 of the fixed clamp 12 and the movable clamp 13 are the same, so the pressure of the adjusting sleeve 31 on the fan-shaped clamp 211 is the same, so that the clamping force of the fixed clamp 12 and the movable clamp 13 on the steel cord is the same.

[0058] Working principle: Before the test, the staff removes the stopper 111 on the slide rail 11, changes the position of the mobile clamp 13 according to the clamping length of the steel cord determined by the test, and then reinstalls the stopper 111 to lock the position of the positioning seat 23 of the mobile clamp 13. The staff straightens the steel cord and passes it through the through hole at the axis of the clamp seat 2 and the outer cylinder 3 of the fixed clamp 12 and the mobile clamp 13, and starts the second rotary driver 151 of the linear drive unit 15 to drive the threaded rod 152 to rotate, driving the threaded sleeve in the mobile seat 33 to move along the threaded rod 1 52 moves, thereby driving the outer cylinder 3 to move along the axis of the threaded rod 152. In the process of the outer cylinder 3 moving away from the chuck seat 2, it drives the adjusting sleeve 31 to move in the opposite direction and approach the chuck seat 2. In the process of the adjusting sleeve 31 moving toward the chuck seat 2, the sleeve head 311 is pressed to fit the tapered end 212 of the fan-shaped clamping block 211, and the fan-shaped clamping block 211 in the chuck seat 2 is pushed to move synchronously along the limiting slide groove 21, so as to center the steel cord. After the clamping is completed, the first rotary driver 14 drives the chuck seat 2 of the mobile clamp 13 to rotate, so as to complete the torsional fatigue test.

[0059] The above embodiments only express one or several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the attached claims.

Claims

1. A device for torsional fatigue testing of steel cords, comprising a frame (1), a slide rail (11) being arranged on the frame (1), a fixed clamp (12) and a movable clamp (13) being slidably mounted on the slide rail (11), characterized in that: The fixed clamp (12) and the movable clamp (13) both comprise a clamp seat (2) and an outer cylinder (3) which are coaxially arranged, and a through hole for allowing the steel cord to pass through is arranged at the axis of the clamp seat (2) and the outer cylinder (3); The chuck seat (2) is provided with a plurality of limiting slide grooves (21) extending radially along the chuck seat (2), and a fan-shaped clamping block (211) is slidably installed in the limiting slide groove (21), and each fan-shaped clamping block (211) is provided with a tapered end (212) at one end close to the outer cylinder (3), and the tapered end (212) has a gradually decreasing taper, and an adjustment sleeve (31) is coaxially arranged in the outer cylinder (3), and the adjustment sleeve (31) is arranged toward a pressing sleeve head (311) provided at one end of the chuck seat (2) and fits against the outer wall of the tapered end (212) of the fan-shaped clamping block (211), and the adjustment sleeve (31) moves along the axis toward the fan-shaped clamping block (211) so that the fan-shaped clamping block (211) moves synchronously along the limiting slide groove (21) to center and clamp the steel cord; The frame (1) is provided with a first rotating driver (14) for driving a clamping head seat (2) of a movable clamp (13) to rotate around its own axis; The outer wall of the adjusting sleeve (31) is provided with a first tooth groove (312) arranged along the axis direction of the adjusting sleeve (31), the inner wall of the outer cylinder (3) is provided with a second tooth groove (32) arranged along the axis direction of the outer cylinder (3), a bracket (22) is provided on the chuck seat (2), a gear (221) is rotatably mounted on the bracket (22), the axis of the gear (221) is perpendicular to the axis of the chuck seat (2), and the first tooth groove (312) of the adjusting sleeve (31) and the second tooth groove (32) of the outer cylinder (3) are respectively meshed and connected with the gear (221); The frame (1) is provided with a linear drive unit (15) for driving the outer cylinder (3) to move along its own axial direction; The linear drive unit (15) comprises a second rotary drive (151) fixedly mounted on one end of the frame (1); a working end of the second rotary drive (151) is coaxially connected to a threaded rod (152); parallel first guide rods (153) are respectively arranged on both sides of the threaded rod (152) on the frame (1); the threaded rod (152) and the first guide rod (153) extend along the length direction of the slide rail (11); The outer cylinder (3) is rotatably mounted on the movable seat (33); the movable seat (33) is provided with a threaded sleeve located on the same straight line as the threaded rod (152), and a first guide hole (332) located on the same straight line as the first guide rod (153); the threaded rod (152) is screwed into the threaded sleeve, and the first guide rod (153) is respectively inserted into the first guide hole (332); A positioning seat (23) is also provided on the slide rail (11), and the clamping head seat (2) in the movable clamp (13) is rotatably mounted in a first mounting frame (231) provided on the positioning seat (23); A plurality of limit blocks (35) are provided at one end of the outer cylinder (3) facing the chuck seat (2), the limit blocks (35) surround the circumference of the adjustment sleeve (31), and a second guide hole (351) parallel to the axis of the outer cylinder (3) is provided on the limit blocks (35); A plurality of second guide rods (24) located in the same straight line as the second guide holes (351) are arranged at one end of the chuck seat (2) facing the outer cylinder (3); the second guide rods (24) are inserted into the second guide holes (351) and extend into the interior of the outer cylinder (3); a limiting head (241) is arranged at one end of the second guide rod (24) located inside the outer cylinder (3); a spring (242) is sleeved on the second guide rod (24); the spring (242) elastically connects the limiting head (241) and the limiting block (35); the elastic force of the spring (242) causes the outer cylinder (3) to move toward the chuck seat (2); A push plate (213) protruding from the surface of the fan-shaped clamp block (211) is provided at one end of each fan-shaped clamp block (211) away from the axis of the clamp seat (2), and a return spring (214) is provided in each limiting slide groove (21). The return spring (214) elastically connects one end of the limiting slide groove (21) close to the axis and the push plate (213) on the fan-shaped clamp block (211). The elastic force of the return spring (214) causes the fan-shaped clamp block (211) to move away from the axis of the clamp seat (2). A first synchronous wheel (25) is coaxially arranged outside the clamping head seat (2) of the movable clamp (13); the first synchronous wheel (25) is connected to a second synchronous wheel (252) through a synchronous belt (251); the second synchronous wheel (252) is rotatably mounted in a second mounting frame (232) arranged on the positioning seat (23); a spline groove is arranged at the axis of the second synchronous wheel (252); The first rotary driver (14) is fixedly mounted on one end of the frame (1); the working end of the first rotary driver (14) is drivingly connected to a spline shaft (141); the spline shaft (141) extends along the length direction of the slide rail (11); and the second synchronous wheel (252) is spline-connected to the spline shaft (141) via a spline groove.

2. The device for steel cord torsional fatigue testing according to claim 1, characterized in that: A limiter (111) for positioning the positioning seat (23) is arranged inside the slide rail (11).

3. The device for steel cord torsional fatigue testing according to claim 1, characterized in that: The outer wall of the adjustment sleeve (31) is provided with a plurality of limit slots (313) extending along the axis of the adjustment sleeve (31); The inner wall of the outer cylinder (3) is provided with clamping strips (34) having the same number as the limiting clamping grooves (313), and the clamping strips (34) are inserted into the limiting clamping grooves (313) of the adjustment sleeve (31).

4. The device for steel cord torsional fatigue testing according to claim 1, characterized in that: The clamping head seat (2) of the fixing clamp (12) is fixedly mounted on the positioning seat (23); The first mounting frame (231) of the chuck seat (2) and the movable seat (33) of the outer cylinder (3) are both provided with avoidance holes for avoiding the spline shaft (141).

5. The device for steel cord torsional fatigue testing according to claim 1, characterized in that: A notch for avoiding the threaded rod (152) is provided on the movable seat (33) of the outer cylinder (3) of the fixed clamp (12); and pitch-adjusting threaded rods (333) extending toward one side of the fixed clamp (12) along the length direction of the slide rail (11) are provided on both sides of the movable seat (33) of the movable clamp (13); the pitch-adjusting threaded rods (333) are inserted into mounting ears (334) provided on both sides of the movable seat (33) of the fixed clamp (12); and a locking nut (335) is spirally mounted on the pitch-adjusting threaded rod (333); and the locking nut (335) fixes the distance between the fixed clamp (12) and the movable seat (33) of the movable clamp (13).

Images