A high strength engineering nylon tie strap tensile strength testing device

Abstract

The application belongs to the technical field of mechanical property detection, and discloses a high-strength engineering nylon cable tie tensile strength testing device which comprises a sample clamping and calibrating module, a hierarchical tension loading module, a force displacement synchronous acquisition module, a slip fracture identification module, a tensile strength evaluation module and a testing and archiving calibration module. The device is used for stably positioning the lock head part, the body part and the tail part of the high-strength engineering nylon cable tie by using the coaxial clamping and calibration, pre-tightening positioning, hierarchical tension loading, force displacement synchronous acquisition, slip fracture identification and effective tensile strength evaluation principles, and simultaneously acquiring tensile force data, loading displacement data, clamp displacement data and cable tie marker displacement data. The device can identify lock tooth runout, lock head slip, body fracture and clamping slip and generate effective tensile force curve, effective elongation curve and tensile strength test results, thereby solving the problems of existing test clamping eccentric load, single data, abnormal slip misjudgment and insufficient test result review.

Description

Technical Field

[0001] This invention belongs to the field of mechanical property testing technology, and in particular relates to a device for testing the tensile strength of high-strength engineering nylon cable ties. Background Technology

[0002] High-strength engineering nylon cable ties are widely used in securing power line harnesses, binding rail transit cables, tightening engineering equipment pipelines, and temporarily fixing outdoor structural components. During use, these ties must withstand long-term tensile loads, vibration loads, and changes in environmental temperature and humidity; their tensile strength directly affects the reliability of the fixation and the safety of use. Engineering nylon cable ties consist of a locking head, a strap body, and a tail strap. Failure under stress is not limited to strap body breakage; it can also manifest as locking tooth skipping, locking head slippage, and clamp slippage. To accurately evaluate the true tensile performance of high-strength engineering nylon cable ties, a tensile strength testing device is needed that can achieve stable clamping, graded loading, simultaneous force and displacement acquisition, slippage and fracture identification, and validity determination.

[0003] The existing technology has at least the following problems that need to be improved: (1) Existing cable tie tensile tests mostly use ordinary tensile testing machines to directly clamp the tail strap and perform unidirectional tension. During the clamping process, the locking head is prone to wobble, the tail strap is not clamped stably, the strap body is twisted and the loading center line is offset. The testing process lacks a positioning calibration mechanism for the locking head, the strap body and the tail strap, which leads to the clamp being overloaded and the clamp slipping, causing interference to the peak tensile force. It is difficult to ensure the consistency of the tensile strength test results of high-strength engineering nylon cable ties.

[0004] (2) Existing testing methods usually use the maximum tensile force recorded by the tension sensor as the basis for judging tensile strength. They lack synchronous acquisition of loading displacement, clamp displacement, cable tie mark displacement and environmental parameters. They also lack a mechanism to distinguish and identify the state of lock tooth jumping, lock head slippage, cable tie breakage and clamp slippage. It is easy to misjudge the abnormal peak value generated by clamp slippage and lock head slippage as the effective tensile strength of the cable tie, resulting in insufficient authenticity and verifiability of the test results. Summary of the Invention

[0005] To address the above issues and overcome the shortcomings of existing technologies, this invention provides a high-strength engineering nylon cable tie tensile strength testing device. Utilizing coaxial clamping calibration, pre-tightening positioning, graded tension loading, synchronous force-displacement acquisition, slippage and fracture identification, and effective tensile strength evaluation principles, it stably positions the locking head, body, and tail of the high-strength engineering nylon cable tie, simultaneously acquiring tensile force data, loading displacement data, clamp displacement data, and cable tie mark displacement data. It identifies locking tooth runout, locking head slippage, body fracture, and clamp slippage, generating effective tensile force curves, effective elongation curves, and tensile strength test results. This solves the problems of uneven clamping, limited data, misjudgment of abnormal slippage, and insufficient test result verification in existing testing methods.

[0006] The technical solution adopted in this invention is as follows: a high-strength engineering nylon cable tie tensile strength testing device, including a sample clamping and calibration module, a graded tension loading module, a force and displacement synchronous acquisition module, a slip fracture identification module, a tensile strength evaluation module, and a test archiving and calibration module.

[0007] The sample clamping and calibration module receives the high-strength engineering nylon cable tie to be tested, positions and clamps the locking head, body and tail of the high-strength engineering nylon cable tie, generates cable tie clamping status data, and sends the cable tie clamping status data to the graded tension loading module and the force-displacement synchronous acquisition module.

[0008] The graded tensioning loading module receives the cable tie clamping status data and, based on the specifications, target loading rate, and preset preload of the high-strength engineering nylon cable tie to be tested, sequentially performs preload loading, uniform tensioning loading, load-holding loading, and fracture termination loading, generating loading execution data, and sending the loading execution data to the force-displacement synchronous acquisition module.

[0009] The force-displacement synchronous acquisition module receives loading execution data and synchronously acquires tensile force data, loading displacement data, fixture displacement data, cable tie mark displacement data, and environmental parameter data during pre-tightening loading, uniform tension loading, load holding loading, and fracture termination loading. It generates force-displacement synchronous acquisition data and sends it to the slip fracture identification module.

[0010] The slippage fracture identification module receives synchronous force and displacement data, and identifies the lock tooth jumping state, lock head slippage state, belt body fracture state, and clamp slippage state based on the tensile force change trend, loading displacement change trend, clamp displacement change trend, and cable tie mark displacement change trend. It generates slippage fracture identification results and sends the slippage fracture identification results to the tensile strength evaluation module.

[0011] The tensile strength assessment module receives synchronous force-displacement data and slip fracture identification results. Based on the synchronous force-displacement data, it calculates the effective tensile force curve, effective elongation curve, maximum effective tensile force, and tensile strength judgment value. Based on the slip fracture identification results, it determines whether the current test is a valid test and generates tensile strength test results.

[0012] The test archiving calibration module receives cable tie clamping status data, loading execution data, force-displacement synchronous acquisition data, slip fracture identification results, and tensile strength test results, generates test process archive data, and calibrates and updates the sample clamping calibration module, graded tension loading module, force-displacement synchronous acquisition module, slip fracture identification module, and tensile strength evaluation module based on the test process archive data.

[0013] Furthermore, the sample clamping and calibration module includes a fixed clamping unit, a movable clamping unit, a lock head limiting unit, a tail strap clamping unit, a coaxial calibration unit, and a pre-tightening positioning unit; the fixed clamping unit limits and supports the lock head, the movable clamping unit provides traction support for the tail strap, the lock head limiting unit restricts the lock head offset, the tail strap clamping unit clamps the tail strap, the coaxial calibration unit ensures that the center of the lock head, the center of the strap body, and the center of the tail strap are located on the same loading center line, and the pre-tightening positioning unit generates cable tie clamping status data after the initial tension reaches the preset pre-tightening force.

[0014] Furthermore, the graded tensioning loading module includes a servo loading unit, a loading rate control unit, a pre-tensioning control unit, a load holding control unit, and a termination protection unit; the servo loading unit drives the moving slide to move along the guide rail, the loading rate control unit controls the moving slide to move according to the target loading rate, the pre-tensioning control unit enters uniform tensioning loading after the tension data reaches the preset pre-tension force, the load holding control unit collects the tension attenuation data and cable tie mark displacement data during the load holding time, and the termination protection unit stops loading according to the sudden drop in tension, the upper limit of loading displacement, and the upper limit of the moving slide's stroke.

[0015] Furthermore, the force-displacement synchronous acquisition module includes a tensile force acquisition unit, a loading displacement acquisition unit, a clamp displacement acquisition unit, a cable tie mark displacement acquisition unit, an environmental parameter acquisition unit, and a synchronization timestamp unit. The tensile force acquisition unit acquires tensile force data, the loading displacement acquisition unit acquires loading displacement data, the clamp displacement acquisition unit acquires clamp displacement data, the cable tie mark displacement acquisition unit acquires cable tie mark displacement data, the environmental parameter acquisition unit acquires environmental parameter data, and the synchronization timestamp unit configures the same sampling timestamp for all types of acquired data to generate force-displacement synchronous acquisition data.

[0016] Furthermore, the slippage and breakage identification module includes a lock tooth jumping identification unit, a lock head slippage identification unit, a belt body breakage identification unit, a clamping slippage identification unit, and an abnormal test marking unit; the lock tooth jumping identification unit identifies the lock tooth jumping state, the lock head slippage identification unit identifies the lock head slippage state, the belt body breakage identification unit identifies the belt body breakage state, the clamping slippage identification unit identifies the clamping slippage state, and the abnormal test marking unit marks valid and invalid tests according to the lock head slippage state, the clamping slippage state, and the belt body breakage state.

[0017] Furthermore, the tensile strength assessment module includes a curve correction unit, a peak extraction unit, an effectiveness determination unit, a fracture mode classification unit, and a test result generation unit. The curve correction unit generates an effective tensile force curve and an effective elongation curve. The peak extraction unit extracts the maximum effective tensile force. The effectiveness determination unit determines whether the current test is a valid test. The fracture mode classification unit generates fracture modes. The test result generation unit generates tensile strength test results based on the maximum effective tensile force, effective elongation, fracture mode, and test effectiveness.

[0018] Furthermore, the test archiving and calibration module includes a test process archiving unit, a calibration sample generation unit, a clamping parameter calibration unit, a loading parameter calibration unit, an acquisition parameter calibration unit, and an identification parameter calibration unit; the test process archiving unit generates test process archive data, the calibration sample generation unit generates a calibration sample set, the clamping parameter calibration unit updates the clamping parameters, the loading parameter calibration unit updates the loading parameters, the acquisition parameter calibration unit updates the acquisition parameters, and the identification parameter calibration unit updates the identification parameters.

[0019] The beneficial effects of this invention are as follows: (1) Utilizing the principle of coaxial clamping calibration and pre-tightening positioning, the lock head, belt body, and tail of the high-strength engineering nylon cable tie to be tested are positioned and clamped through the sample clamping calibration module. Coaxial calibration ensures that the center of the lock head, belt body, and tail are located on the same loading center line. The technical effect is to reduce the influence of lock head sway, belt body torsion, tail clamping offset, and fixture off-center load on the testing process. It solves the problems of unstable clamping, inconsistent loading direction, and poor test repeatability caused by direct clamping of the cable tie by the existing ordinary fixture. (2) Utilizing the principle of graded tension loading and synchronous force-displacement acquisition, the graded tension loading module sequentially performs pre-tension loading, uniform tension loading, load holding loading, and fracture termination loading. The synchronous force-displacement acquisition module synchronously acquires tensile force data, loading displacement data, clamp displacement data, cable tie mark displacement data, and environmental parameter data. The technical effect is to obtain synchronous force-displacement acquisition data that can reflect the actual stress and deformation process of the cable tie, solving the problem that existing tests rely only on single tensile force data and cannot distinguish between clamp deformation and cable tie elongation. (3) By utilizing the principles of slip fracture identification and effective tensile strength assessment, the slip fracture identification module identifies the lock tooth jumping state, lock head slipping state, belt body fracture state and clamping slippage state. Then, the tensile strength assessment module calculates the effective tensile force curve, effective elongation curve, maximum effective tensile force and tensile strength judgment value. Based on the slip fracture identification results, the tensile strength test results are generated. The technical effect is to distinguish and evaluate clamping slippage, lock head slippage and actual belt body fracture, which solves the problem that the existing test misjudges the abnormal slip peak as the effective tensile strength and the test conclusion has insufficient verifiability. Attached Figure Description

[0020] The accompanying drawings are provided to further understand the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the invention and do not constitute a limitation thereof.

[0021] Figure 1 This is a flowchart of the sample clamping and calibration process proposed in this invention; Figure 2 This is a flowchart of the graded tension loading and synchronous acquisition process proposed in this invention; Figure 3 This is a flowchart of the slip fracture identification and strength assessment proposed in this invention. Detailed Implementation

[0022] Example 1, see Figures 1-3 The present invention provides a high-strength engineering nylon cable tie tensile strength testing device, including a sample clamping and calibration module, a graded tension loading module, a force and displacement synchronous acquisition module, a slip fracture identification module, a tensile strength evaluation module, and a test archiving and calibration module.

[0023] The sample clamping and calibration module receives the high-strength engineering nylon cable tie to be tested, positions and clamps the locking head, body and tail of the high-strength engineering nylon cable tie, generates cable tie clamping status data, and sends the cable tie clamping status data to the graded tension loading module and the force-displacement synchronous acquisition module.

[0024] The graded tensioning loading module receives the cable tie clamping status data and, based on the specifications, target loading rate, and preset preload of the high-strength engineering nylon cable tie to be tested, sequentially performs preload loading, uniform tensioning loading, load-holding loading, and fracture termination loading, generating loading execution data, and sending the loading execution data to the force-displacement synchronous acquisition module.

[0025] The force-displacement synchronous acquisition module receives loading execution data and synchronously acquires tensile force data, loading displacement data, fixture displacement data, cable tie mark displacement data, and environmental parameter data during pre-tightening loading, uniform tension loading, load holding loading, and fracture termination loading. It generates force-displacement synchronous acquisition data and sends it to the slip fracture identification module.

[0026] The slippage fracture identification module receives synchronous force and displacement data, and identifies the lock tooth jumping state, lock head slippage state, belt body fracture state, and clamp slippage state based on the tensile force change trend, loading displacement change trend, clamp displacement change trend, and cable tie mark displacement change trend. It generates slippage fracture identification results and sends the slippage fracture identification results to the tensile strength evaluation module.

[0027] The tensile strength assessment module receives synchronous force-displacement data and slip fracture identification results. Based on the synchronous force-displacement data, it calculates the effective tensile force curve, effective elongation curve, maximum effective tensile force, and tensile strength judgment value. Based on the slip fracture identification results, it determines whether the current test is a valid test and generates tensile strength test results.

[0028] The test archiving calibration module receives cable tie clamping status data, loading execution data, force-displacement synchronous acquisition data, slip fracture identification results, and tensile strength test results, generates test process archive data, and calibrates and updates the sample clamping calibration module, graded tension loading module, force-displacement synchronous acquisition module, slip fracture identification module, and tensile strength evaluation module based on the test process archive data.

[0029] With the cooperation of the above modules, this device can simultaneously complete sample positioning, graded loading, synchronous force and displacement acquisition, lock head slippage identification, clamp slippage rejection, and tensile strength evaluation during the tensile strength test of high-strength engineering nylon cable ties. This reduces misjudgments caused by relying solely on the maximum tensile force value and improves the stability and verifiability of the tensile strength test results of high-strength engineering nylon cable ties.

[0030] Example 2: This example is based on all the above examples. The sample clamping and calibration module specifically includes a fixed clamping unit, a movable clamping unit, a locking head limiting unit, a tail belt clamping unit, a coaxial calibration unit, and a pre-tightening positioning unit.

[0031] The fixed clamping unit is set at one end of the test base. The fixed clamping unit includes a lock head support seat, a lock head limiting groove and an arc-shaped bearing block. The lock head support seat is fixedly connected to the test base. The lock head limiting groove is set on the upper surface of the lock head support seat. The arc-shaped bearing block is set at the front end of the lock head limiting groove. The lock head of the high-strength engineering nylon cable tie to be tested is embedded in the lock head limiting groove, and the cable tie body extends along the loading direction after passing around the arc-shaped bearing block.

[0032] The movable clamping unit is located at the other end of the test base. The movable clamping unit includes a movable slide, a tail belt clamping seat and a guide slide rail. The movable slide is slidably connected to the guide slide rail, and the tail belt clamping seat is fixed on the movable slide. The tail belt passes through the tail belt clamping seat and is clamped by the tail belt clamping seat.

[0033] The lock head limiting unit includes a lock head pressing block and a lock head lateral limiting block. The lock head pressing block is pressed against the upper surface of the lock head, and the lock head lateral limiting block is set on the left and right sides of the lock head to keep the lock head in a stable position during the tensioning loading process.

[0034] The tail belt clamping unit includes an upper clamping block, a lower clamping block, an anti-slip textured surface, and a pressure adjusting component. The upper clamping block and the lower clamping block are arranged opposite to each other. The anti-slip textured surface is respectively arranged on the opposite clamping surfaces of the upper clamping block and the lower clamping block. The pressure adjusting component drives the upper clamping block to move to the lower clamping block, so that the tail belt is clamped between the upper clamping block and the lower clamping block.

[0035] The coaxial calibration unit includes a laser centering device, a center scale, and a clamp angle adjustment seat. The laser centering device emits centering light along the loading direction. The center scale is set between the lock head support seat and the tail belt clamping seat. The clamp angle adjustment seat adjusts the horizontal angle of the tail belt clamping seat so that the center of the lock head, the center of the belt body, and the center of the tail belt are located on the same loading center line.

[0036] The pre-tightening positioning unit includes a pre-tightening drive and a pre-tightening force sensor. The pre-tightening drive drives the movable slide to move along the guide slide rail. The pre-tightening force sensor collects the initial tension generated during the pre-tightening process. After the initial tension reaches the preset pre-tightening force, it generates cable tie clamping status data.

[0037] With the above structure, the sample clamping and calibration module can stably arrange the locking head, belt body and tail of the high-strength engineering nylon cable tie on the same loading center line, reducing the impact of locking head sway, belt body torsion and clamp off-center load on the test results.

[0038] Example 3: Based on all the above examples, the graded tension loading module specifically includes a servo loading unit, a loading rate control unit, a pre-tension control unit, a load holding control unit, and a termination protection unit.

[0039] The servo loading unit includes a servo motor, a ball screw, a transmission nut, and a loading beam. The servo motor is connected to the ball screw via a transmission mechanism. The transmission nut is sleeved on the ball screw. The loading beam is connected to the transmission nut. The movable slide is connected to the loading beam, so that when the servo motor rotates, it drives the movable slide to move along the guide rail.

[0040] The loading rate control unit controls the servo motor speed according to the target loading rate, so that the moving slide moves away from the fixed clamping unit at the target loading rate, thereby forming a tension loading on the high-strength engineering nylon cable tie to be tested.

[0041] The pretension control unit controls the servo loading unit to perform low-speed loading according to the preset pretension force. When the tension data reaches the preset pretension force, the pretension termination displacement is recorded, and uniform tension loading is entered.

[0042] When the tensile force data reaches the preset load-holding force, the load-holding control unit controls the servo loading unit to maintain the position of the loading beam, collects the tensile force attenuation data and cable tie mark displacement data during the load-holding time, and obtains the load-holding loading data.

[0043] The termination protection unit controls the servo loading unit to stop loading based on the sudden drop in tension, the upper limit of loading displacement, and the upper limit of the travel of the moving slide. When any of the following states occur: belt breakage, lock head slippage, or clamp slippage, breakage termination loading data is generated.

[0044] The graded tensioning loading module generates loading execution data based on the servo motor speed, loading beam position, moving slide position, and loading duration during the pre-tensioning loading, uniform tensioning loading, load-holding loading, and fracture termination loading processes.

[0045] The graded tensioning loading module calculates the single-cycle displacement increment based on the preset loading rate and sampling period, using the following formula:

[0046] in, For the first The single-cycle displacement increment of each sampling period; For the first The target loading rate for each sampling period; The sampling period.

[0047] Through the above processing, the graded tensioning loading module can avoid the instantaneous impact on the locking head and the disturbance of the tail strap clamping caused by direct rapid stretching, so that the high-strength engineering nylon cable tie under test can complete the tensile strength test under stable pre-tensioning, uniform speed stretching and load-bearing detection conditions.

[0048] Example 4: This example is based on all the above examples. The force-displacement synchronous acquisition module specifically includes a tension acquisition unit, a loading displacement acquisition unit, a clamp displacement acquisition unit, a cable tie mark displacement acquisition unit, an environmental parameter acquisition unit, and a synchronization timestamp unit.

[0049] The tension acquisition unit includes a tension sensor and a signal conditioner. The tension sensor is installed between the loading beam and the moving slide, and the signal conditioner is electrically connected to the tension sensor. The tension sensor acquires tension data during the tension loading process.

[0050] The loading displacement acquisition unit includes a displacement encoder, which is connected to a ball screw. The displacement encoder acquires the loading displacement data generated by the movement of the loading beam.

[0051] The fixture displacement acquisition unit includes a fixed fixture displacement marker, a moving fixture displacement marker, and an industrial camera. The industrial camera acquires the relative position changes of the fixed fixture displacement marker and the moving fixture displacement marker to generate fixture displacement data.

[0052] The cable tie mark displacement acquisition unit includes a lock head mark point, a belt body mark point, and a tail belt mark point. An industrial camera acquires the relative displacement of the lock head mark point, the belt body mark point, and the tail belt mark point to generate cable tie mark displacement data.

[0053] The environmental parameter acquisition unit includes a temperature sensor and a humidity sensor. The temperature sensor acquires the ambient temperature, and the humidity sensor acquires the ambient humidity, generating environmental parameter data.

[0054] The synchronization timestamp unit configures the same sampling timestamp for tensile force data, loading displacement data, clamp displacement data, cable tie mark displacement data, and environmental parameter data to generate synchronous force-displacement acquisition data.

[0055] The force-displacement synchronous acquisition module calculates the effective tensile force based on the tensile force data and the fixture deformation compensation amount. The calculation formula is as follows:

[0056] in, The effective tensile force at the t-th sampling time; The tension is measured by the tension sensor at the t-th sampling time; The initial tension at the end of the pre-tightening process; This is the equivalent stiffness coefficient of the fixture; Let be the clamp deformation compensation amount at the t-th sampling time.

[0057] Regarding parameter adjustments: Step 1: Sampling frequency adjustment; when the rate of change of tension increases, increase the sampling frequency of the tension acquisition unit and the load displacement acquisition unit; when the rate of change of tension is stable, decrease the sampling frequency.

[0058] Step 2: Adjust the image acquisition frequency; when the cable tie mark displacement data changes continuously, increase the acquisition frequency of the industrial camera; when the cable tie mark displacement data remains stable, decrease the acquisition frequency of the industrial camera.

[0059] Step 3: Adjust the equivalent stiffness coefficient of the fixture; when the correspondence between the fixture displacement data and the tensile force data in the no-load calibration test shifts, update the equivalent stiffness coefficient of the fixture.

[0060] Through the above processing, the force-displacement synchronous acquisition module can synchronously acquire sensor tension, mechanical loading displacement, clamp displacement and cable tie deformation, so that the subsequent tensile strength assessment is based on the effective tension and effective elongation.

[0061] Example 5: This example is based on all the above examples. The slippage breakage identification module specifically includes a lock tooth jump identification unit, a lock head slippage identification unit, a belt body breakage identification unit, a clamp slippage identification unit, and an abnormal test marking unit.

[0062] The locking tooth runout identification unit identifies the locking tooth runout state of the high-strength engineering nylon cable tie under test at the locking tooth engagement position based on the step descent segment in the tension curve, the abrupt change in the displacement of the belt body marker point, and the change in the displacement of the lock head marker point.

[0063] The lock head slippage recognition unit identifies the lock head slippage state caused by the belt body relative to the lock head based on the relative displacement change between the lock head marking point and the belt body marking point.

[0064] The belt breakage identification unit identifies the belt breakage state based on the sudden drop in tensile force data, the change in the breakage spacing of the cable tie mark displacement data, and the belt breakage image captured by the industrial camera.

[0065] The clamping slippage recognition unit identifies the clamping slippage state of the tail belt relative to the tail belt clamping seat based on the relative displacement change between the tail belt mark point and the moving clamp displacement mark.

[0066] The abnormal test marking unit marks the current test according to the lock head slippage state, clamping slippage state, and lock tooth jumping state. When the clamping slippage state reaches the slippage threshold, the current test is marked as invalid; when the belt body breaks and the clamping slippage state does not reach the slippage threshold, the current test is marked as valid.

[0067] The slippage breakage identification module calculates the lock head slippage index based on the relative displacement between the lock head marker point and the belt body marker point. The calculation formula is as follows:

[0068] in, Let be the lock head slippage index at the t-th sampling time; Let be the displacement of the lock head marker point at the t-th sampling time; Let be the displacement of the marker point on the belt at the t-th sampling time; The initial effective length of the high-strength engineering nylon cable tie to be tested; To prevent the correction factor from being zero in the denominator.

[0069] The slippage fracture identification module calculates the effective elongation based on the loaded displacement data, clamp displacement data, and lock head slippage index. The calculation formula is as follows:

[0070] in, This represents the effective elongation at the t-th sampling time. The loading displacement data is at the t-th sampling time. The fixture displacement data at the t-th sampling time; Let be the lock head slippage index at the t-th sampling time; This represents the initial effective length of the high-strength engineering nylon cable tie to be tested.

[0071] Regarding parameter adjustments: Step 1: Adjust the lock tooth runout threshold; when the step descent segment matches the lock tooth meshing change in the image acquired by the industrial camera, lower the lock tooth runout threshold; when the tension curve noise causes misidentification, increase the lock tooth runout threshold.

[0072] Step 2: Lock head slip threshold adjustment; when the relative displacement between the lock head marker and the belt body marker continues to increase, decrease the lock head slip threshold; when the relative displacement is only caused by image jitter, increase the lock head slip threshold.

[0073] Step 3: Adjust the clamping slip threshold; when the relative displacement between the tail belt marker and the moving fixture displacement marker continues to increase, lower the clamping slip threshold; when there are no obvious slip marks in the tail belt clamping area, increase the clamping slip threshold.

[0074] Through the above processing, the slippage fracture identification module can distinguish between actual strap body fracture, lock head slippage, and clamp slippage, avoiding misjudging the peak tensile force generated by clamp slippage as the tensile strength of the cable tie.

[0075] Example 6: This example is based on all the above examples. The tensile strength evaluation module specifically includes a curve correction unit, a peak value extraction unit, an effectiveness determination unit, a fracture mode classification unit, and a test result generation unit.

[0076] The curve correction unit generates an effective tensile force curve and an effective elongation curve based on the effective tensile force and the effective elongation.

[0077] The peak extraction unit extracts the maximum effective tensile force from the effective tensile force curve and records the effective elongation, sampling time, and loading displacement data corresponding to the maximum effective tensile force.

[0078] The validity determination unit determines whether the current test is valid based on the clamping slippage state, the lock head slippage state, and the belt body breakage state. When the clamping slippage state reaches the slippage threshold, the current test is determined to be invalid. When the belt body breaks and the clamping slippage state does not reach the slippage threshold, the current test is determined to be valid.

[0079] The fracture mode classification unit divides the fracture modes into belt body fracture mode, lock head slippage mode, lock tooth jumping mode and clamping slippage mode based on the slippage fracture identification results.

[0080] The test result generation unit generates tensile strength test results based on the maximum effective tensile force, effective elongation, fracture mode, and test validity.

[0081] The tensile strength assessment module calculates the tensile strength judgment value based on the maximum effective tensile force, effective elongation, lock head slippage index, and clamping slippage state. The calculation formula is as follows:

[0082] in, This is the value for determining tensile strength. To the maximum effective tensile force; This represents the effective elongation at the sampling moment corresponding to the maximum effective tensile force. The lock head slippage index at the sampling moment corresponding to the maximum effective tensile force; This is the clamping slippage state value; , , and These are the judgment weight coefficients for the corresponding items.

[0083] Regarding parameter adjustments: Step 1: Adjust the judgment weight coefficient; when the test sample is mainly in the belt body fracture mode, increase the judgment weight coefficient corresponding to the maximum effective tensile force; when the test sample is mainly in the lock head slippage mode, increase the judgment weight coefficient corresponding to the lock head slippage index.

[0084] Step 2: Adjust the validity judgment parameters; when the number of invalid tests increases, increase the judgment weight coefficient corresponding to the clamp slip state value; when a valid test is mistakenly judged as an invalid test, decrease the judgment weight coefficient corresponding to the clamp slip state value.

[0085] Step 3: Adjust the fracture mode classification parameters; when the image acquired by the industrial camera is inconsistent with the tensile curve recognition result, increase the weight of the image recognition result in fracture mode classification.

[0086] Through the above processing, the tensile strength evaluation module can generate tensile strength test results by comprehensively considering effective tensile force, effective elongation, lock slippage index, and clamping slippage state, making the test conclusions of high-strength engineering nylon cable ties closer to the actual stress failure state.

[0087] Example 7: This example is based on all the above examples. The test archiving and calibration module specifically includes a test process archiving unit, a calibration sample generation unit, a clamping parameter calibration unit, a loading parameter calibration unit, a data acquisition parameter calibration unit, and an identification parameter calibration unit.

[0088] The test process archiving unit binds the cable tie clamping status data, loading execution data, force and displacement synchronous acquisition data, slip fracture identification results, and tensile strength test results according to the sample number, batch number, test time, and operator number to generate test process archiving data.

[0089] The calibration sample generation unit extracts valid test samples, invalid test samples, lock head slippage samples, clamp slippage samples, and belt body breakage samples from the archived data of the test process to generate a calibration sample set.

[0090] The clamping parameter calibration unit updates the clamping pressure of the tail belt clamping seat, the limiting distance of the lock head limiting groove, and the angle calibration parameters of the coaxial calibration unit based on the clamping slippage samples in the invalid test samples.

[0091] The loading parameter calibration unit updates the preload, target loading rate, holding load, and fracture termination threshold based on the stability of the tensile curve in the valid test samples.

[0092] The acquisition parameter calibration unit updates the sampling frequency, synchronization timestamp, and image acquisition frequency based on the synchronization deviation between the tension data, loading displacement data, clamp displacement data, and cable tie mark displacement data.

[0093] The identification parameter calibration unit updates the lock tooth jump threshold, lock head slip threshold, clamp slip threshold, and fracture mode classification parameters based on lock head slippage samples, clamp slippage samples, and belt breakage samples.

[0094] Through the above processing, the test archiving calibration module can continuously calibrate the clamping, loading, acquisition and identification parameters using historical test results, so that the device can maintain the consistency of test results during the batch testing of high-strength engineering nylon cable ties of different specifications.

Claims

1. A device for testing the tensile strength of high-strength engineering nylon cable ties, characterized in that: It includes a sample clamping and calibration module, a graded tension loading module, a force and displacement synchronous acquisition module, a slip fracture identification module, a tensile strength evaluation module, and a test archiving and calibration module; The sample clamping and calibration module receives the high-strength engineering nylon cable tie to be tested, positions and clamps the locking head, body and tail of the high-strength engineering nylon cable tie to be tested, and generates cable tie clamping status data. The graded tensioning loading module receives cable tie clamping status data and, based on the specifications, target loading rate, and preset preload of the high-strength engineering nylon cable tie to be tested, sequentially performs preload loading, uniform tensioning loading, load-holding loading, and fracture termination loading to generate loading execution data. The force-displacement synchronous acquisition module receives loading execution data and synchronously acquires tensile force data, loading displacement data, clamp displacement data, cable tie mark displacement data, and environmental parameter data to generate force-displacement synchronous acquisition data. The slippage fracture identification module receives synchronous force and displacement data, and identifies the lock tooth jumping state, lock head slippage state, belt body fracture state and clamp slippage state based on the tensile force change trend, loading displacement change trend, clamp displacement change trend and cable tie mark displacement change trend, and generates slippage fracture identification results. The tensile strength assessment module receives synchronous force-displacement data and slip fracture identification results, calculates the effective tensile force curve, effective elongation curve, maximum effective tensile force and tensile strength judgment value based on the synchronous force-displacement data, and generates tensile strength test results based on the slip fracture identification results. The test archiving calibration module receives cable tie clamping status data, loading execution data, force and displacement synchronous acquisition data, slip fracture identification results, and tensile strength test results, generates test process archive data, and performs calibration updates based on the test process archive data.

2. The high-strength engineering nylon cable tie tensile strength testing device according to claim 1, characterized in that: The sample clamping and calibration module includes a fixed clamping unit, a movable clamping unit, a lock head limiting unit, a tail strap clamping unit, a coaxial calibration unit, and a pre-tightening positioning unit. The fixed clamping unit limits and supports the lock head, the movable clamping unit provides traction support for the tail strap, the lock head limiting unit restricts the lock head offset, the tail strap clamping unit clamps the tail strap, the coaxial calibration unit ensures that the center of the lock head, the center of the strap body, and the center of the tail strap are located on the same loading center line, and the pre-tightening positioning unit generates cable tie clamping status data after the initial tension reaches the preset pre-tightening force.

3. The high-strength engineering nylon cable tie tensile strength testing device according to claim 2, characterized in that: The fixed clamping unit includes a lock head support, a lock head limiting groove, and an arc-shaped bearing block. The lock head of the high-strength engineering nylon cable tie to be tested is embedded in the lock head limiting groove, and the cable tie body extends along the loading direction after passing around the arc-shaped bearing block. The movable clamping unit includes a movable slide, a tail belt clamping seat, and a guide slide rail. The movable slide is slidably connected to the guide slide rail, and the tail belt clamping seat is fixed on the movable slide. The tail belt passes through the tail belt clamping seat and is clamped by the tail belt clamping seat.

4. The high-strength engineering nylon cable tie tensile strength testing device according to claim 3, characterized in that: The graded tensioning loading module includes a servo loading unit, a loading rate control unit, a pre-tensioning control unit, a load holding control unit, and a termination protection unit. The servo loading unit drives the moving slide to move along the guide rail. The loading rate control unit controls the moving slide to move according to the target loading rate. The pre-tensioning control unit enters uniform tensioning loading after the tension data reaches the preset pre-tension force. The load holding control unit collects the tension decay data and cable tie mark displacement data during the load holding time. The termination protection unit stops loading according to the sudden drop in tension, the upper limit of loading displacement, and the upper limit of the moving slide's stroke.

5. The high-strength engineering nylon cable tie tensile strength testing device according to claim 4, characterized in that: The force-displacement synchronous acquisition module includes a tensile force acquisition unit, a loading displacement acquisition unit, a clamp displacement acquisition unit, a cable tie mark displacement acquisition unit, an environmental parameter acquisition unit, and a synchronization timestamp unit. The tensile force acquisition unit acquires tensile force data, the loading displacement acquisition unit acquires loading displacement data, the clamp displacement acquisition unit acquires clamp displacement data, the cable tie mark displacement acquisition unit acquires cable tie mark displacement data, the environmental parameter acquisition unit acquires environmental parameter data, and the synchronization timestamp unit configures the same sampling timestamp for all types of acquired data to generate force-displacement synchronous acquisition data.

6. The high-strength engineering nylon cable tie tensile strength testing device according to claim 5, characterized in that: The slippage fracture identification module includes a lock tooth jump identification unit, a lock head slippage identification unit, a belt body fracture identification unit, a clamping slippage identification unit, and an abnormal test marking unit; the lock tooth jump identification unit identifies the lock tooth jump state based on the step drop segment in the tension curve, the abrupt change in the displacement of the belt body marking point, and the change in the displacement of the lock head marking point; The lock cylinder slippage recognition unit identifies the lock cylinder slippage state based on the relative displacement change between the lock cylinder marker point and the belt body marker point. The belt breakage identification unit identifies the belt breakage state based on the sudden drop in tensile force data, the change in the breakage spacing of the cable tie mark displacement data, and the belt breakage image; the clamp slippage identification unit identifies the clamp slippage state based on the relative displacement change between the tail belt mark and the moving clamp displacement mark.

7. The high-strength engineering nylon cable tie tensile strength testing device according to claim 6, characterized in that: The tensile strength evaluation module includes a curve correction unit, a peak value extraction unit, an effectiveness determination unit, a fracture mode classification unit, and a test result generation unit. The curve correction unit generates effective tensile force curves and effective elongation curves based on effective tensile force and effective elongation. The peak extraction unit extracts the maximum effective tensile force from the effective tensile force curve. The validity determination unit determines whether the current test is valid based on the clamping slippage state, lock head slippage state, and belt body breakage state. The fracture mode classification unit generates fracture modes based on the slippage fracture identification results. The test result generation unit generates tensile strength test results based on the maximum effective tensile force, effective elongation, fracture mode, and test validity.

8. The high-strength engineering nylon cable tie tensile strength testing device according to claim 7, characterized in that: The test archiving and calibration module includes a test process archiving unit, a calibration sample generation unit, a clamping parameter calibration unit, a loading parameter calibration unit, a data acquisition parameter calibration unit, and an identification parameter calibration unit. The test process archiving unit generates test process archiving data based on cable tie clamping status data, loading execution data, force and displacement synchronous acquisition data, slip fracture identification results, and tensile strength test results. The calibration sample generation unit generates a set of calibration samples based on the archived data from the testing process. The clamping parameter calibration unit updates the clamping parameters, the loading parameter calibration unit updates the loading parameters, the acquisition parameter calibration unit updates the acquisition parameters, and the identification parameter calibration unit updates the identification parameters.

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