A testing device and method for tpu multifilament bundle performance

Abstract

The application discloses a kind of TPU multi-filament harness performance test equipment and method thereof, including outer frame, vertical frame fixed on the outer frame and roll rack fixedly installed on the outer wall of vertical frame;Steel roller is installed in the roll rack, and a plurality of annular isolation grooves are arranged on the circumference of steel roller along the axial direction, each annular isolation groove is used to independently accommodate a TPU silk line and pass in V-shaped type;Stage is movably arranged on the vertical frame, and lifting assembly is installed on the outer wall of vertical frame above the roll rack, and the driving end of lifting assembly is connected with stage.The application utilizes the structure of steel roller, annular isolation groove, lifting assembly, stage, S-type tension sensor and multi-thread single-cylinder compression assembly etc., to complete the real limit tensile test of TPU multi-filament harness in the stroke of short gauge length equipment.

Description

Technical Field

[0001] This invention relates to the field of filament testing technology, specifically to a testing device and method for the performance of TPU multifilament bundles. Background Technology

[0002] TPU yarn is a flexible polymer yarn that combines the high elasticity of rubber with the strength of plastic. It can quickly recover its original shape after repeated bending or impact, and also has excellent abrasion resistance and tear resistance. Its tensile properties are usually tested using a tensile tester. During the test, the upper fixture stretches upward at a constant speed until the yarn breaks. High-precision force sensors and displacement sensors (or extensometers directly clamped on the gauge length) collect tensile and elongation data in real time, generating complete stress-strain curves. These curves can reveal the mechanical behavior of TPU molecular chains from elastic deformation and microphase structure rearrangement to molecular chain orientation strengthening and finally to fracture. Based on this, testers obtain key indicators such as fracture point, yield point, and stress at a given elongation, and closely observe whether there are any abnormalities in the fracture mode. For example, the textile yarn toughness measuring device disclosed in authorization announcement number CN222994220U and the yarn tensile tester disclosed in authorization announcement number CN219625220U both adopt a single yarn fixing scheme. That is, the lower fixed position is fixed to one end of the yarn by a clamp, while the tension sensor at the upper free end is fixed to the other end of the yarn by a clamp. The tensile properties of the yarn are obtained by ultimate tensile testing. However, for the overall tensile properties of TPU multi-filament bundles, the short gauge length and direct clamping tensile method are difficult to complete the true ultimate tensile test within the limited equipment stroke and stable effective gauge length. That is, for high resilience TPU materials, the sample often has to stop due to the travel limitation of the equipment before reaching the true strength limit. In addition, the tensile curve of multi-filament bundles contains a lot of nonlinear deformation caused by yarn arrangement adjustment, twist elimination, and inter-filament slippage in the early stage, which will affect the multi-filament test. Summary of the Invention

[0003] The purpose of this invention is to provide a testing device and method for the performance of TPU multifilament harnesses. A standard-length TPU filament is wound in a V-shape around each annular isolation groove of a steel roller. The upper ends of the TPU multifilament harness are then fixed by a multi-head single-cylinder clamping assembly. After the TPU multifilament harness is positioned, the control box drives the lifting assembly to move the platform, two S-shaped tension sensors, and two multi-head single-cylinder clamping assemblies upwards. During this upward movement, the TPU multifilament harness is subjected to tensile force until it breaks, and the tensile force value is collected. This allows for the completion of the true ultimate tensile test of the TPU multifilament harness within the short gauge length of the device's travel, thereby solving the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a testing device for the performance of TPU multifilament harnesses, comprising an outer frame, a vertical frame fixed to the outer frame, and a roller frame fixedly installed on the outer wall of the vertical frame; The steel roller installed in the roller frame has several annular isolation grooves arranged at intervals along its axial direction on its circumferential surface. Each annular isolation groove is used to independently accommodate a TPU filament and wrap around it in a V-shape. A platform that can be moved up and down on the vertical frame, and a lifting assembly is installed on the outer wall of the vertical frame above the roller frame, with the drive end of the lifting assembly connected to the platform. Two S-shaped tension sensors are fixedly installed on the platform, and a multi-wire head single-cylinder clamping assembly is fixedly connected to the lower end of the S-shaped tension sensors. Each of the multi-wire head single-cylinder clamping assemblies is used to clamp the ends of all TPU threads located on the same side. The control box is mounted on one side of the outer frame via a cantilever. The control box is electrically connected to the lifting assembly, two S-shaped tension sensors, and two multi-wire single-cylinder clamping assemblies.

[0005] Preferably, the lifting assembly includes a support plate fixed to the outer wall of the frame, a double sprocket shaft rotatably mounted on the upper end of the support plate, two lower sprocket shafts rotatably mounted on the lower end of the support plate, and a chain installed between the lower sprocket shafts and the double sprocket shafts. A carrier plate is vertically and slidably mounted on the outer wall of the support plate away from the frame via two guide rails. One end of the chain is fixedly connected to one side of the outer wall of the carrier plate, and the other side of the outer wall of the carrier plate is fixedly connected to the platform. A stepper motor is installed at the lower position of the support plate, and the output shaft of the stepper motor is fixedly connected to one of the lower sprocket shafts via a coupling.

[0006] Preferably, the support plate has an internal slot for the platform and the multi-line single-cylinder pressing assembly to slide up and down.

[0007] Preferably, the platform includes two side frames fixed at intervals on one side outer wall of the platform and a loop-shaped foot frame bolted to the top wall of the two side frames. The two S-shaped tension sensors are symmetrically arranged below the loop-shaped foot frame, and the upper end of the S-shaped tension sensor is fixed to the bottom end of the loop-shaped foot frame through a T-shaped flange.

[0008] Preferably, the multi-wire head single-cylinder pressing assembly includes a connecting plate fixed to the lower end of an S-type tension sensor via a T-flange, a right-angle cylinder seat fixed to the bottom of the connecting plate, a hydraulic cylinder horizontally installed in the right-angle cylinder seat, and a pressing arm that can be moved up and down below the connecting plate via a guide structure. The piston rod end of the hydraulic cylinder is fixed with an inclined top seat, and the inclined top seat and the pressing arm are slidably engaged. When the piston rod of the hydraulic cylinder extends, the inclined top seat forces the pressing arm to move upward.

[0009] Preferably, a sloping groove is provided on one side of the bottom end of the crimping arm, and the sloping top seat is located in the sloping groove and slides in cooperation with the sloping groove.

[0010] Preferably, the guide structure includes an outer cover fixed to the bottom of the connecting plate, a flat plate fixed to the bottom of the outer cover, and guide rods vertically slidably installed on both sides inside the flat plate. The upper ends of the two guide rods are fixed to the crimping arm, and the lower ends of the two guide rods are fixed to the bottom arm. An elastic return structure is installed between the flat plate and the crimping arm.

[0011] Preferably, the elastic return structure includes an L-shaped arm seat bolted to the bottom end of the plate, an upper T-shaped pin fixed to the crimping arm, and a lower T-shaped pin installed on the outer wall of the L-shaped arm seat facing the outer cover, with a tension spring connecting the lower T-shaped pin and the upper T-shaped pin.

[0012] Preferably, the top end of the L-shaped arm seat is provided with a through hole for the tension spring to pass through.

[0013] This invention also provides a method for testing the performance of TPU multifilament harnesses, using the aforementioned equipment, and comprising the following steps: S1: The staff takes out several TPU threads of equal length and folds the TPU multi-thread in half along the center line. The two upper ends of the TPU multi-thread are fixed by a multi-thread head single-cylinder clamping assembly. At this time, the TPU multi-thread forms a V-shape and falls naturally vertically. Then, each TPU thread is wrapped around the bottom arc surface of the steel roller. Each annular isolation groove can just accommodate one TPU thread. During the adjustment process, it is necessary to prevent the threads in adjacent grooves from getting tangled, twisted, or knotted. At this point, the multiple TPU threads are positioned and connected in parallel between the steel roller and the multi-thread head single-cylinder clamping assemblies on both sides with the same geometric path and initial tension. S2: The lifting assembly is activated via the control box. The lifting assembly has preset rising speed, sampling frequency of S-type tension sensor and stopping conditions. S3: The lifting assembly drives the platform, S-shaped tension sensors, and multi-thread single-cylinder clamping assembly to move smoothly upward. When the platform moves upward, the two multi-thread single-cylinder clamping assemblies on the left and right, along with the clamped ends of the wires, rise synchronously. At this time, the fixed steel roller remains stationary, and each V-shaped wire that passes around the steel roller is stretched. The TPU wires gradually move from a relaxed state to an elastic stretching stage, and all the wires begin to share the increasing tension. The tension is directly transmitted to the two S-shaped tension sensors through the multi-thread single-cylinder clamping assembly. The S-shaped tension sensors transmit the force value signal to the acquisition system of the control box in real time. S4: Initially, the threads show uniform elongation and the surface is slightly white. As the tension increases, individual threads with microscopic defects or thinner diameters may break first. At this time, the total tension will drop temporarily, but the remaining intact threads continue to be stretched until all the threads break completely. S5: After the test is completed, the staff operates the control box to make the lifting component move in the opposite direction, the platform descends back to the initial position, then releases the two multi-thread single-cylinder clamping components, removes the broken wire ends, and cleans the annular isolation groove on the steel roller to remove any remaining debris.

[0014] Compared with the prior art, the beneficial effects of the present invention are: the TPU multifilament wire harness performance testing equipment and method, through the structure of steel rollers, annular isolation groove, lifting assembly, platform, S-shaped tensile sensor and multi-wire head single cylinder clamping assembly, etc., cooperate with each other to complete the true limit tensile test of TPU multifilament wire harness within the short gauge length of the equipment stroke; By utilizing the V-shaped winding path on the steel roller, a standard-length TPU filament is arranged in a folded manner. When the lifting assembly drives the platform, S-shaped tension sensor, and multi-thread single-cylinder clamping assembly to move upward as a whole, the equipment only needs to move a short distance for the filament to achieve twice the actual elongation. This allows the highly elastic TPU multi-filament bundle to be fully stretched to natural breakage without changing the equipment's hardware stroke. Furthermore, each TPU filament is individually constrained within an annular isolation groove on the surface of the steel roller, with the grooves separated from each other to effectively prevent the filaments from hooking, rubbing, or tangling. Next, the two ends of the filaments are fixed by the multi-head single-cylinder clamping assembly. The operator only needs to pass each filament of the TPU multifilament bundle around the corresponding annular isolation groove of the steel roller in sequence, and the control box can complete all subsequent actions. That is, the lifting assembly moves upward at a set constant speed, the S-shaped tension sensor continuously samples until all filaments break, the equipment automatically records the peak tension and stops, realizing an automated and repeatable operation process for the tensile performance of TPU multifilament bundles. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 2 ; Figure 3 This is a side cross-sectional view of the present invention. Figure 4 This is a three-dimensional cross-sectional structural diagram of the present invention; Figure 5 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 3 ; Figure 6 This is a three-dimensional structural diagram of the assembled frame and lifting assembly of the present invention. Figure 7 This is a three-dimensional structural diagram of the lifting assembly and platform of the present invention after assembly. Figure 8This is a three-dimensional cross-sectional view of the assembled S-type tension sensor and multi-wire single-cylinder clamping assembly of the present invention. Figure 9 This is a side cross-sectional view of the S-type tension sensor and the multi-wire single-cylinder clamping assembly of the present invention after assembly. Figure 10 This is a three-dimensional structural diagram of the multi-line head single-cylinder clamping assembly of the present invention; Figure 11 This is a three-dimensional structural diagram of the crimping arm of the present invention.

[0016] In the diagram: 1. Outer frame; 2. Vertical frame; 21. Roller frame; 3. Steel roller; 31. Annular isolation groove; 4. Platform; 41. Side frame; 42. Recurved frame with feet; 5. Lifting assembly; 51. Support plate; 511. Empty groove; 52. Double sprocket shaft; 53. Lower sprocket shaft; 54. Stepper motor; 55. Carrier plate; 56. Chain; 6. S-type tension sensor; 7. Multi-wire single-cylinder pressing assembly; 71. Connecting plate; 711. Outer cover; 712. Flat plate; 713. Base arm; 714. Guide rod; 72. Right-angle cylinder seat; 73. Hydraulic cylinder; 74. Inclined top seat; 75. Pressing arm; 751. Inclined groove; 76. Elastic return structure; 761. L-shaped arm seat; 762. Lower T-pin; 763. Upper T-pin; 764. Tension spring; 8. Control box. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0018] Example 1, by Figures 1 to 4 The present invention includes an outer frame 1, a vertical frame 2 fixed on the outer frame 1, and a roller frame 21 fixedly installed on the outer wall of the vertical frame 2. The outer frame 1 and the vertical frame 2 serve as the supporting skeleton and load-bearing structure of the entire equipment. The steel roller 3 installed in the roller frame 21 has several annular isolation grooves 31 arranged at intervals along its axial direction on its circumferential surface. Each annular isolation groove 31 is used to independently accommodate a TPU filament and wrap around it in a V-shape. The steel roller 3 achieves a displacement multiplication effect and provides a smooth, undamaged force-bearing guide surface, and does not move itself. The width of each annular isolation groove 31 is slightly larger than the diameter of a single TPU filament, and the depth ensures that the filament can fall completely into the bottom of the groove without getting stuck, preventing adjacent filaments from contacting, rubbing or tangling with each other. A platform 4 is movable up and down on the vertical frame 2. A lifting assembly 5 is installed on the outer wall of the vertical frame 2 above the roller frame 21. The drive end of the lifting assembly 5 is connected to the platform 4. Two S-shaped tension sensors 6 are fixedly installed on the platform 4, and a multi-wire head single-cylinder clamping assembly 7 is fixedly connected to the lower end of the S-shaped tension sensor 6. Each multi-wire head single-cylinder clamping assembly 7 is used to clamp the ends of all TPU threads located on the same side. And a control box 8 can be installed on one side of the outer frame 1 via a cantilever. The control box 8 is electrically connected to the lifting assembly 5, two S-shaped tension sensors 6 and two multi-wire single-cylinder clamping assemblies 7 respectively. The control box 8 integrates a programmable logic controller, a motor driver, a signal acquisition module, and a human-machine interface. The control box 8 collects the signal from the S-type tension sensor 6 and displays the force value after amplification, filtering, and AD conversion. The tension on the left and right sides of the V-shaped winding structure may not be completely equal. The two S-type tension sensors 6 measure the total tension on the left and the total tension on the right respectively, and the sum of them gives the total tension. The S-type tension sensor 6 needs to exclude the weight of the multi-wire single-cylinder clamping assembly 7 during calibration.

[0019] This embodiment provides a method for testing the performance of TPU multifilament harnesses, using the aforementioned equipment, and includes the following steps: S1: The staff takes out several TPU threads of equal length and folds the TPU multi-thread in half along the center line. The two upper ends of the TPU multi-thread are fixed by a multi-thread single-cylinder pressing component 7. At this time, the TPU multi-thread forms a V-shape and falls naturally vertically. Then, each TPU thread is wrapped around the bottom arc surface of the steel roller 3. Each annular isolation groove 31 can just accommodate one TPU thread. During the adjustment process, it is necessary to prevent the threads in adjacent grooves from getting tangled, twisted, or knotted. At this point, the multiple TPU threads are positioned and connected in parallel between the steel roller 3 and the multi-thread single-cylinder pressing components 7 on both sides with the same geometric path and initial tension. S2: The lifting assembly 5 is activated via the control box 8. The lifting assembly 5 has preset rising speed, sampling frequency of S-type tension sensor 6, and stopping conditions. S3: The lifting assembly 5 drives the platform 4, S-type tension sensor 6, and multi-thread single-cylinder clamping assembly 7 to move smoothly upward. When the platform 4 moves upward, the two multi-thread single-cylinder clamping assemblies 7 on the left and right rise synchronously together with the clamped ends of the wires. At this time, the fixed steel roller 3 remains stationary, and each V-shaped wire that passes around the steel roller is stretched. The TPU wires gradually enter the elastic stretching stage from the relaxed state. All the wires begin to bear the increasing tension together. The tension is directly transmitted to the two S-type tension sensors 6 through the multi-thread single-cylinder clamping assembly 7. The S-type tension sensors 6 transmit the force value signal to the acquisition system of the control box 8 in real time. S4: Initially, the threads show uniform elongation and the surface is slightly white. As the tension increases, individual threads with microscopic defects or thinner diameters may break first. At this time, the total tension will drop temporarily, but the remaining intact threads continue to be stretched until all the threads break completely. S5: After the test is completed, the staff operates the control box 8 to make the lifting component 5 move in the opposite direction, the platform 4 descends back to the initial position, and then releases the two multi-thread single-cylinder clamping components 7, removes the broken wire ends, and cleans the annular isolation groove 31 on the steel roller 3 to remove any remaining debris.

[0020] Example 2, based on Example 1, is... Figure 5 , Figure 6 and Figure 7 The lifting assembly 5 includes a support plate 51 fixed to the outer wall of the frame 2, a double sprocket shaft 52 rotatably mounted on the upper end of the support plate 51, two lower sprocket shafts 53 rotatably mounted on the lower end of the support plate 51, and a chain 56 installed between the lower sprocket shafts 53 and the double sprocket shafts 52. A carrier plate 55 is vertically slidably mounted on the outer wall of the support plate 51 away from the frame 2 via two guide rails. One end of the chain 56 is fixedly connected to one side of the outer wall of the carrier plate 55, and the other side of the outer wall of the carrier plate 55 is fixedly connected to the platform 4. A stepper motor 54 is installed at the lower position of the support plate 51, and the output shaft of the stepper motor 54 is fixedly connected to one of the lower sprocket shafts 53 via a coupling. The support plate 51 is provided with a slot 511 for the platform 4 and the multi-wire head single cylinder clamping assembly 7 to slide up and down. The slot 511 provides enough space for the two multi-wire head single cylinder clamping assemblies 7 to rise and fall. When the lifting assembly 5 is working, the control box 8 sends precise pulse commands to the stepper motor 54 according to the preset program to control its uniform rotation. The stepper motor 54 drives the lower sprocket shaft 53 to rotate, and then the chain 56 between the lower sprocket shaft 53 and the double sprocket shaft 52 drives the carrier plate 55, the platform 4, the S-shaped tension sensor 6 and the multi-thread single-cylinder clamping assembly 7 to rise, so as to meet the constant strain rate required by the TPU yarn during the stretching process. The platform 4 includes two side frames 41 fixed at intervals on one side outer wall of the carrier plate 55 and a loop-shaped foot frame 42 bolted to the top wall of the two side frames 41. Two S-shaped tension sensors 6 are symmetrically arranged below the loop-shaped foot frame 42, and the upper end of the S-shaped tension sensor 6 is fixed to the bottom end of the loop-shaped foot frame 42 through a T-shaped flange. The side frames 41 and the loop-shaped foot frame 42 constitute a moving platform for carrying the S-shaped tension sensor 6 and the multi-wire head single cylinder clamping assembly 7. The side frames 41 and the carrier plate 55 cooperate with the support plate 51 through the guide rail to suppress the slight vibration or tilt that may occur during movement.

[0021] Example 3, based on Example 2, by Figure 8 , Figure 9 , Figure 10 and Figure 11 The multi-wire head single-cylinder clamping assembly 7 includes a connecting plate 71 fixed to the lower end of an S-type tension sensor 6 via a T-type flange, a right-angle cylinder seat 72 fixed to the bottom end of the connecting plate 71, a hydraulic cylinder 73 horizontally installed in the right-angle cylinder seat 72, and a pressing arm 75 that can be moved up and down below the connecting plate 71 via a guide structure. The piston rod end of the hydraulic cylinder 73 is fixed with an inclined top seat 74, which slides in cooperation with the pressing arm 75. When the piston rod of the hydraulic cylinder 73 extends, the inclined top seat 74 forces the pressing arm 75 to move upward. An inclined groove 751 is provided on one side of the bottom end of the pressing arm 75, and the inclined top seat 74 is located in the inclined groove 751 and slides in cooperation with the inclined groove 751. The guide structure includes an outer cover 711 fixed to the bottom of the connecting plate 71, a flat plate 712 fixed to the bottom of the outer cover 711, and guide rods 714 vertically slidably installed on both sides inside the flat plate 712. The upper ends of the two guide rods 714 are fixed to the crimping arm 75, and the lower ends of the two guide rods 714 are fixed to the bottom arm 713. An elastic return structure 76 is installed between the flat plate 712 and the crimping arm 75. Each upper end of the TPU multi-filament harness is neatly arranged between the crimping arm 75 and the connecting plate 71. Then, the control box 8 controls the solenoid valve connected to the hydraulic cylinder 73 to open, and hydraulic oil enters the hydraulic cylinder 73. Its piston rod pushes the inclined top seat 74 to move horizontally. Since the inclined top seat 74 slides in contact with the inclined groove 751 of the crimping arm 75, the crimping arm 75 is forced to move upward. During this process, the elastic return structure 76 deforms until the crimping arm 75 fixes the wire end on the connecting plate 71. At this time, the ends of multiple wires are simultaneously crimped. During the upward movement of the crimping arm 75, the crimping arm 75 will drive the guide rod 714 and the bottom arm 713 to move upward together, thereby improving the lifting stability of the crimping arm 75 through the guide rod 714 and the bottom arm 713. The elastic return structure 76 includes an L-shaped arm seat 761 bolted to the bottom of the plate 712, an upper T-shaped pin 763 fixed to the crimping arm 75, and a lower T-shaped pin 762 installed on the outer wall of the L-shaped arm seat 761 facing the outer cover 711. A tension spring 764 is connected between the lower T-shaped pin 762 and the upper T-shaped pin 763. The top of the L-shaped arm seat 761 is provided with a through hole for the tension spring 764 to pass through. Since the L-shaped arm seat 761 is fixed to the lower end of the plate 712, the L-shaped arm seat 761 and the lower T-shaped pin 762 remain stationary. When the crimping arm 75 is driven to move upward, the upper T-shaped pin 763 moves upward accordingly, and the tension spring 764 is stretched. When the piston rod of the steel roller 3 returns to its original position, the crimping arm 75 resets synchronously under the reset force of gravity and the tension of the tension spring 764.

[0022] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0023] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A testing device for the performance of TPU multifilament harnesses, comprising an outer frame (1), a vertical frame (2) fixed to the outer frame (1), and a roller frame (21) fixedly installed on the outer wall of the vertical frame (2), characterized in that: The steel roller (3) installed in the roller frame (21) has several annular isolation grooves (31) arranged at intervals along its axial direction on its circumferential surface. Each annular isolation groove (31) is used to independently accommodate a TPU filament and wrap around it in a V-shape. A platform (4) is movable up and down on the vertical frame (2). A lifting assembly (5) is installed on the outer wall of the vertical frame (2) above the roller frame (21). The driving end of the lifting assembly (5) is connected to the platform (4). Two S-shaped tension sensors (6) are fixedly installed on the platform (4), and a multi-wire head single-cylinder clamping assembly (7) is fixedly connected to the lower end of the S-shaped tension sensor (6). Each of the multi-wire head single-cylinder clamping assemblies (7) is used to clamp the ends of all TPU threads located on the same side. And a control box (8) can be installed on one side of the outer frame (1) via a cantilever. The control box (8) is electrically connected to the lifting assembly (5), two S-type tension sensors (6) and two multi-wire single-cylinder clamping assemblies (7), respectively. The multi-wire head single-cylinder pressing assembly (7) includes a connecting plate (71) fixed to the lower end of the S-type tension sensor (6) via a T-type flange, a right-angle cylinder seat (72) fixed to the bottom end of the connecting plate (71), a hydraulic cylinder (73) horizontally installed in the right-angle cylinder seat (72), and a pressing arm (75) that can be moved up and down below the connecting plate (71) via a guide structure. The piston rod end of the hydraulic cylinder (73) is fixed with an inclined top seat (74). The inclined top seat (74) and the pressing arm (75) are slidably engaged. When the piston rod of the hydraulic cylinder (73) extends, the inclined top seat (74) forces the pressing arm (75) to move upward. The guide structure includes an outer cover (711) fixed to the bottom of the connecting plate (71), a plate (712) fixed to the bottom of the outer cover (711), and guide rods (714) vertically slidably installed on both sides inside the plate (712). The upper ends of the two guide rods (714) are fixed to the crimping arm (75), and the lower ends of the two guide rods (714) are fixed with a bottom arm (713). An elastic return structure (76) is installed between the plate (712) and the crimping arm (75). The elastic return structure (76) includes an L-shaped arm seat (761) bolted to the bottom of the plate (712), an upper T-shaped pin (763) fixed on the crimping arm (75), and a lower T-shaped pin (762) installed on the outer wall of the L-shaped arm seat (761) facing the outer cover (711). A tension spring (764) is connected between the lower T-shaped pin (762) and the upper T-shaped pin (763).

2. The testing equipment for the performance of TPU multifilament harnesses according to claim 1, characterized in that: The lifting assembly (5) includes a support plate (51) fixed on the outer wall of the frame (2), a double sprocket shaft (52) rotatably mounted on the upper end of the support plate (51), two lower sprocket shafts (53) rotatably mounted on the lower end of the support plate (51), and a chain (56) installed between the lower sprocket shafts (53) and the double sprocket shafts (52). A carrier plate (55) is vertically slidably mounted on the outer wall of the support plate (51) away from the frame (2) via two guide rails. One end of the chain (56) is fixedly connected to one side of the outer wall of the carrier plate (55), and the other side of the outer wall of the carrier plate (55) is fixedly connected to the platform (4). A stepper motor (54) is installed at the lower position of the support plate (51), and the output shaft of the stepper motor (54) is fixedly connected to one of the lower sprocket shafts (53) via a coupling.

3. The testing equipment for the performance of TPU multifilament harnesses according to claim 2, characterized in that: The support plate (51) is provided with a slot (511) for the platform (4) and the multi-line single-cylinder pressing assembly (7) to slide up and down.

4. The testing equipment for the performance of TPU multifilament harnesses according to claim 2, characterized in that: The platform (4) includes two side frames (41) fixed at intervals on one side outer wall of the platform (55) and a loop-shaped frame with feet (42) bolted to the top wall of the two side frames (41). The two S-shaped tension sensors (6) are symmetrically arranged below the loop-shaped frame with feet (42), and the upper end of the S-shaped tension sensor (6) is fixed to the bottom end of the loop-shaped frame with feet (42) through a T-shaped flange.

5. The testing equipment for the performance of TPU multifilament harnesses according to claim 1, characterized in that: A sloping groove (751) is provided on one side of the bottom end of the crimping arm (75), and the sloping top seat (74) is located in the sloping groove (751) and slides in cooperation with the sloping groove (751).

6. The testing equipment for the performance of TPU multifilament harnesses according to claim 1, characterized in that: The top of the L-shaped arm seat (761) is provided with a through hole for the tension spring (764) to pass through.

7. A method for testing the performance of TPU multifilament harnesses, using the equipment described in any one of claims 1-6, characterized in that: Includes the following steps: S1: The staff takes out several TPU threads of equal length and folds the TPU multi-threaded threads in half along the center line. The two upper ends of the TPU multi-threaded threads are fixed by a multi-threaded single-cylinder pressing assembly (7). At this time, the TPU multi-threaded threads form a V-shape and fall naturally vertically. Then, each TPU thread is wrapped around the bottom arc surface of the steel roller (3). Each annular isolation groove (31) can just accommodate one TPU thread. During the adjustment process, it is necessary to prevent the threads in adjacent grooves from getting tangled, twisted, or knotted. At this point, the multiple TPU threads are positioned and connected in parallel between the steel roller (3) and the multi-threaded single-cylinder pressing assemblies (7) on both sides with the same geometric path and initial tension. S2: The lifting assembly (5) is activated through the control box (8). The lifting assembly (5) has preset rising speed, sampling frequency of S-type tension sensor (6) and stopping conditions. S3: The lifting assembly (5) drives the platform (4), S-type tension sensor (6), and multi-thread single-cylinder clamping assembly (7) to move upward smoothly. When the platform (4) moves upward, the two multi-thread single-cylinder clamping assemblies (7) on the left and right rise together with the clamped ends of the wires. At this time, the fixed steel roller (3) remains stationary, and each V-shaped wire that passes around the steel roller is stretched. The TPU wire gradually enters the elastic stretching stage from the relaxed state. All the wires begin to bear the increasing tension together. The tension is directly transmitted to the two S-type tension sensors (6) through the multi-thread single-cylinder clamping assembly (7). The S-type tension sensor (6) transmits the force value signal to the acquisition system of the control box (8) in real time. S4: Initially, the threads show uniform elongation and the surface is slightly white. As the tension increases, individual threads with microscopic defects or thinner diameters may break first. At this time, the total tension will drop temporarily, but the remaining intact threads continue to be stretched until all the threads break completely. S5: After the test is completed, the staff operates the control box (8) to make the lifting component (5) move in the opposite direction, the platform (4) descends back to the initial position, and then releases the two multi-thread single-cylinder clamping components (7), removes the broken wire ends, and cleans the annular isolation groove (31) on the steel roller (3) to remove any remaining debris.

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