Detection device for new energy automobile cable harness

Abstract

The invention discloses a cable harness detection device for a new energy automobile, and belongs to the technical field of harness detection. The device is composed of a fixing mechanism, a tensioning mechanism, a bending mechanism, a torsion mechanism, a detection module and a control system. Through a pneumatic self-adaptive clamping structure and an elastic tensioning mechanism, stable fixation and constant tensioning of the wire harness are realized; the servo driving push rod and the rotatable mounting plate can simulate bending in multiple directions; the three-jaw chuck type torsion mechanism realizes low-speed and high-torque reciprocating torsion; the detection module integrates electrical performance detection and infrared temperature sensing, and monitors the conduction state, resistance, insulation strength and temperature rise in real time; the control system realizes automatic control of bending, torsion and composite loading based on a PLC, and can be connected with an upper computer or a cloud platform to realize data uploading and life curve analysis. The device can truly simulate the complex working condition of the vehicle, and improves the detection precision and reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of harness detection, and in particular to a detection device for a new energy vehicle cable harness. BACKGROUND

[0002] With the rapid development of the new energy vehicle industry, the degree of vehicle electrification and intelligence is continuously improving. As a key component of the circuit system, the number and complexity of the vehicle cable harness have significantly increased. The harness not only bears the functions of power transmission and signal transmission, but also directly relates to the stable operation of the vehicle power system, control system and safety system. Once the harness has a broken circuit, poor contact or insulation failure, it may cause the vehicle power to be interrupted, the control to fail or the safety device to fail, thereby seriously threatening the safety of driving.

[0003] To ensure the quality of the harness, the existing detection devices generally simulate the bending process of the harness through mechanical driving and realize the through performance test of the harness by combining the on-off detection. However, the existing technology generally has the following deficiencies: first, most of the devices can only realize the bending of the harness in a single plane or limited direction, and cannot truly reproduce the multi-directional complex stress of the harness caused by the movement of the suspension system, the vibration of the vehicle body and the impact of the road during vehicle driving; second, when the motor or driving mechanism needs to be reversed repeatedly at a high frequency, problems such as heating, wear, noise and vibration are easy to occur, resulting in unstable detection results; third, the existing devices generally lack real-time monitoring of parameters such as bending force, angle change and conduction impedance during the test, and cannot comprehensively evaluate the comprehensive performance of the harness under dynamic working conditions.

[0004] Therefore, the existing detection method still has deficiencies in terms of simulation authenticity, test accuracy and equipment durability, and it is difficult to meet the higher requirements of the new energy vehicle harness for reliability and safety under high-strength working conditions. SUMMARY

[0005] The purpose of the present application is to provide a detection device for a new energy vehicle cable harness to solve the above-mentioned problems.

[0006] The specific technical scheme adopted is as follows: a cable harness detection device for a new energy vehicle, comprising: a fixing mechanism: comprising a lower guide column and an upper guide column arranged in parallel, a wire clamp one is axially slidably mounted on the lower guide column through a linear bearing, a wire clamp two is axially slidably mounted on the upper guide column through a linear bearing, the wire clamp one and the wire clamp two adopt a V-shaped clamping groove structure and are equipped with a pneumatic clamping assembly for adaptively clamping and fixing the upper and lower ends of the cable harness;

[0007] A tensioning mechanism: spring elastic bodies are arranged on the outer sides of the lower guide column and the upper guide column, respectively, the elastic bodies are connected to the wire clamp one and the wire clamp two through a connecting rod mechanism, and are used for straightening and keeping the cable harness in a taut state.

[0008] The bending mechanism includes a rotatable servo drive mounting plate and a pair of push rods symmetrically arranged thereon, the end of the push rod is provided with a V-shaped polyurethane material clamping groove, and the push rod can move along the length direction of the cable harness and push the cable harness to bend through reciprocating movement, and the mounting plate can rotate around the center of the cable harness to change the bending direction.

[0009] The torsion mechanism is arranged in the wire clamp one and includes a servo motor, a speed reducer and a three-jaw chuck type torsion clamp for driving the cable harness to reciprocatingly twist around the axis thereof.

[0010] The detection module includes an electrical performance detection unit and an infrared temperature sensor for real-time monitoring of the conduction state, resistance change, insulation strength and temperature rise of the cable harness during the bending or twisting process.

[0011] The control system includes a PLC controller and a sensor, the controller is electrically connected with the bending mechanism, the torsion mechanism and the detection module, and is used for setting the bending angle, the torsion angle, the loading frequency and the cycle number, and storing and analyzing the detection data.

[0012] In a further embodiment, the servo motor is connected to the speed reducer through a shaft coupling, the output end of the speed reducer is provided with a torsion clamping jaw, and the servo motor rotates to drive the cable harness to reciprocatingly twist through the torsion clamping jaw.

[0013] Through the above technical solution, high-precision, low-speed and large-torque output can be realized, and the torsion loading is stable and reliable, and the clamping force is uniform.

[0014] In a further embodiment, the detection module further includes an infrared temperature sensor for monitoring the temperature rise of the cable harness under high-frequency bending or twisting.

[0015] Through the above technical solution, insulation aging and potential thermal damage problems can be found.

[0016] In a further embodiment, the control system includes a programmable logic controller, which can automatically perform bending, twisting and composite loading tests according to a preset working condition curve.

[0017] Through the above technical solution, the automation degree and consistency of the device are improved.

[0018] In a further embodiment, the wire clamp one and the wire clamp two adopt a pneumatic self-adaptive clamping structure, which can automatically adjust the clamping force according to the cable harness with different diameters and outer skin hardness.

[0019] Through the above technical solution, it can be avoided that the clamping is too tight or too loose.

[0020] In a further embodiment, the control system is in communication connection with an upper computer or a cloud platform, for realizing real-time uploading, storage and statistical analysis of test data.

[0021] Through the technical scheme, remote monitoring and life database establishment are facilitated.

[0022] In a further embodiment, the end of the push rod of the bending mechanism is provided with a V-shaped or circular-arc clamping groove, and the inner surface of the clamping groove is provided with an anti-skid pattern, for avoiding the wire harness from slipping off or being damaged during the bending process.

[0023] Through the technical scheme, bending precision can be improved.

[0024] In a further embodiment, the reciprocating mechanism adopts a linear motor or a ball screw transmission, so as to reduce wear and improve movement precision.

[0025] Through the technical scheme, noise and wear can be reduced, and equipment durability can be improved.

[0026] In a further embodiment, the detection module is configured with a data processing unit, for generating a life curve of the cable wire harness in real time, including a bending frequency-resistance change relationship and a torsion angle-insulation strength relationship.

[0027] Through the technical scheme, the life law of the wire harness can be intuitively reflected.

[0028] In a further embodiment, the device can be operated in different temperature and humidity environment chambers to simulate environmental stress under actual road conditions.

[0029] Through the technical scheme, the authenticity and reference value of test results are improved.

[0030] Compared with the prior art, the present application has the following beneficial effects:

[0031] (1) By adopting the pneumatic self-adaptive V-shaped clamping groove structure, the clamping force can be automatically adjusted according to wire harnesses of different diameters and outer skin hardness, so as to avoid damage to the wire harness caused by clamping too tightly or slipping off caused by clamping too loosely, thereby improving the reliability and applicability of wire harness fixation.

[0032] (2) By arranging spring elastic bodies outside the upper and lower guide columns and connecting the spring elastic bodies with the wire clamp through a connecting rod mechanism, automatic straightening and constant tensioning of the cable wire harness are realized, test errors caused by wire harness relaxation or bending in the prior art are effectively eliminated, and test precision is ensured.

[0033] (3) The bending mechanism drives symmetrical push rods through a servo-driven mounting plate, so as to realize multi-directional and high-precision bending loading; the end of the push rod is provided with a V-shaped or circular-arc clamping groove with an anti-skid pattern, so as to effectively prevent the wire harness from slipping and being damaged during the bending process, thereby improving bending precision and stability.

[0034] (4) The torsion mechanism adopts a combined structure of a servo motor, a speed reducer and a three-jaw chuck type torsion clamp, and can realize stable and reliable reciprocating torsion loading with low speed and large torque, avoiding the problems of insufficient torque or uneven loading in the prior art.

[0035] (5) The detection module not only includes monitoring of on-off state, resistance and insulation strength, but also is configured with an infrared temperature sensor to detect temperature rise in real time, so as to timely find insulation aging and potential thermal damage problems; and through a data processing unit, a cable harness life curve can be generated, and the relationship between bending times, resistance change, torsion angle and insulation strength can be intuitively reflected.

[0036] (6) The control system adopts a PLC controller, can automatically perform bending, torsion and composite loading test according to a preset working condition curve, significantly improves the automation degree and consistency of the device, and can communicate with an upper computer or a cloud platform to realize real-time uploading, storage and statistical analysis of test data, and is convenient for remote monitoring and establishment of a life database. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 is a schematic diagram of the overall structure of the present application;

[0038] Figure 2 is a schematic diagram of the structure of the fixing mechanism and the tensioning mechanism in the present application;

[0039] Figure 3 is a schematic diagram of the structure of the torsion mechanism, the bending mechanism and the detection module in the present application;

[0040] Figure 4 is a "bending times-resistance change" curve and a "bending times-temperature rise" curve in the present application.

[0041] Reference signs: 1, fixing mechanism; 101, upper guide column; 102, lower guide column; 103, wire clamp two; 104, wire clamp one; 2, bending mechanism; 401, servo motor; 402, speed reducer; 403, three-jaw chuck type torsion clamp; 501, push rod; 502, mounting plate; 503, V-shaped clamping groove. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0043] The embodiment provides a cable harness detection device for new energy vehicles, and the overall structure is shown in the accompanying Figure 1 The device body is composed of a fixing mechanism 1, a tensioning mechanism, a bending mechanism 2, a torsion mechanism, a detection module and a control system, and each part is fixed on the same base through an integrated rack to form a modular and detachable detection unit.

[0044] In the embodiment, as shown in the accompanying Figures 1 to 3 The base is an aluminum alloy integral machining part with a thickness of 20 mm, has sufficient rigidity and stability, and can maintain the accuracy of the device in a long-term high-frequency vibration environment. The outside of the rack is covered with a transparent acrylic safety cover to prevent the operator from contacting the moving parts during the detection process.

[0045] The fixing mechanism 1 includes two parallel lower guide columns 102 and upper guide columns 101, which have a diameter of 25 mm and are made of high-strength chrome-plated steel, and the two ends are fixed to the base through a cross beam to ensure the coaxiality of the movement. The wire clamp one 104 is axially slidably installed on the lower guide column 102 through a linear bearing, and the wire clamp two 103 is axially slidably installed on the upper guide column 101 through a linear bearing. The wire clamp one 104 and the wire clamp two 103 adopt a V-shaped groove structure with a V-shaped groove angle of 90°, and the inside is covered with a wear-resistant polyurethane layer to avoid damage to the wire harness skin. The outer side of the wire clamp is provided with a pneumatic driving cylinder, and the clamping force is adjustable between 0.2 and 0.6 MPa, which can adapt to new energy vehicle cable harnesses with different diameters and different hardnesses.

[0046] The tensioning mechanism is composed of spring elastic bodies arranged outside the lower guide column 102 and the upper guide column 101, and the elastic bodies are connected to the wire clamp one 104 and the wire clamp two 103 through a connecting rod mechanism. Each group of spring elastic coefficient is 30 N / mm, which can automatically straighten the cable harness before detection and maintain constant tension. This design ensures that the wire harness is always in an initial uniform stress state before bending or torsion loading, effectively eliminating errors caused by relaxation or pre-deformation.

[0047] The bending mechanism 2 is arranged in the middle of the device and mainly composed of a servo drive mounting plate 502, a double push rod 501 assembly and a end clamping groove. The servo driver adopts a model 750W AC servo motor 401, which drives the mounting plate 502 to rotate around the center of the wire harness. The double push rod 501 is symmetrically arranged along the length direction of the cable, and the stroke of the push rod 501 is 100 mm, which realizes high-precision reciprocating motion through ball screw transmission. The V-shaped clamping groove 503 at the end of the push rod 501 is covered with polyurethane and has fine anti-slip lines, which can firmly clamp the wire harness and avoid slipping and damage under high-frequency loading.

[0048] The torsion mechanism is installed inside the wire clamp 104 and mainly consists of a servo motor 401, a shaft coupling, a reducer 402 and a three-jaw chuck type torsion clamp 403. The servo motor 401 has a power of 400 W and a maximum output speed of 1500 rpm. The reducer 402 reduces the speed to a low speed and outputs a large torque. The three-jaw chuck stably clamps the cable end, and realizes the reciprocating torsion of ±180°. The PLC is used to set the torsion angle, speed and cycle number, so as to ensure that the test working condition is consistent with the actual vehicle application.

[0049] The detection module includes two parts:

[0050] (1) The electrical performance detection unit is used to monitor the conduction resistance, insulation strength and short-time open circuit of the cable harness in real time, and the sampling frequency is as high as 1 kHz;

[0051] (2) The infrared temperature sensor is used to monitor the temperature rise of the cable surface. The temperature measurement range is -20℃~200℃, and the accuracy is ±0.5℃. Through multi-point temperature acquisition, local heating phenomenon caused by frequent bending or torsion can be found, and the insulation aging risk can be evaluated.

[0052] The control system uses PLC as the core control unit, and has a built-in detection working condition curve library. The bending angle, torsion angle, frequency and cycle number are set through the touch screen human-machine interface. The detection data can be uploaded to the upper computer or cloud platform in real time, and remote storage and big data analysis are realized.

[0053] In this embodiment, the device is used to simulate the multi-directional bending working condition of the new energy vehicle cable harness in the complex vehicle environment. The test steps are as follows:

[0054] Sample preparation: select a power cable with a length of 800 mm and an outer diameter of 18 mm, and a rated voltage of 600 V;

[0055] Fixing and tensioning: place the upper and lower ends of the cable in the wire clamp 104 and the wire clamp 103 respectively, and clamp them through the pneumatic device. After the tensioning mechanism is started, the cable is automatically straightened and kept at a constant tension of about 150 N;

[0056] Bending loading: set the rotation angle of the servo mounting plate 502 to ±90°, the stroke of the push rod 501 to 40 mm, the loading frequency to 2 Hz, and the cycle number to 10^5 times;

[0057] Detection process: during the loading process, the electrical performance detection unit monitors the resistance value change in real time. If the resistance suddenly increases or the instantaneous open circuit occurs, the time point and the bending number are recorded immediately. The infrared sensor collects the temperature rise of the cable surface in real time.

[0058] Test end: generate the "bending number-resistance change" curve and the "bending number-temperature rise" curve, and evaluate the cable durability in combination with the actual working condition.

[0059] The test results show that, as shown in Figure 4 the cable resistance fluctuation and local temperature rise occurred at 8.2x10^4 cycles, indicating that the insulation layer has been fatigue aged. The data can be directly used to evaluate the service life of the cable in the vehicle application.

[0060] In this embodiment, the reliability test capability of the device under torsion working condition. The test steps are as follows:

[0061] Sample preparation: select new energy vehicle signal harness, diameter 10mm, length 600mm;

[0062] Fixing and clamping: the two ends of the harness are fixed by wire clamps, and the lower end is connected to the torsion mechanism through a three-jaw chuck;

[0063] Torsion loading: set the torsion angle ±120°, the loading frequency is 1Hz, and the cycle number is 5x10^4;

[0064] Detection process: real-time monitoring of insulation strength and on-state resistance, and collecting temperature rise data;

[0065] End of test: generate "torsion angle-insulation strength relationship curve", and judge the reliability of the harness under high frequency torsion through data analysis.

[0066] The test results show that the insulation strength of the signal harness decreases significantly at 4.5x10^4 cycles, and the local temperature rise exceeds 20℃. This indicates that the harness needs to increase support points or use materials with better torsion resistance in the actual vehicle body layout.

[0067] Considering that the new energy vehicle harness often bears bending and torsion stress at the same time in actual operation, this embodiment carries out composite loading test, and the test steps are as follows:

[0068] Sample preparation: power cable and signal harness combination harness, diameter range 6~20mm;

[0069] Test condition: set the bending angle ±60°, the bending frequency 1Hz; the torsion angle ±90°, the torsion frequency 0.5Hz, both are loaded at the same time, and the cycle number is 2x10^4;

[0070] Detection and collection: the control system records electrical parameters, temperature rise data and loading times at the same time, and generates a life curve under composite working condition in real time.

[0071] Result analysis: the test results show that under the condition of composite loading, the service life of the harness is reduced by about 30%~40% compared with the single loading condition. This result provides an important reference for the optimization of vehicle cable layout.

[0072] In this embodiment, in order to verify the adaptability of the device in extreme environment, environmental stress simulation is introduced. The specific implementation steps are as follows:

[0073] Environmental conditions: The whole machine is placed in a temperature and humidity controllable environment chamber, the temperature range is-40℃~85℃, and the humidity range is 10%~95%RH;

[0074] Sample preparation: New energy vehicle fast charging cable, diameter 25mm, rated current 200A;

[0075] Test conditions: Under the conditions of 85℃ and 95%RH, ±45° bending cycle is carried out for 5*10^4 times, and the on-resistance and surface temperature rise are monitored at the same time.

[0076] Result analysis: It is found that the service life of the cable is obviously shortened in high temperature and high humidity environment, the insulation resistance decreases rapidly, and the surface temperature rise exceeds 25℃. The data shows that additional insulation protection and heat dissipation measures are needed when used in extreme environment.

[0077] In this embodiment, through the connection with the upper computer and the cloud platform, all detection data is transmitted to the cloud platform in real time through the Ethernet interface after collection; the system automatically generates a life curve, and stores it according to the wire harness model, diameter and material properties to form a database; researchers can remotely monitor the detection process through PC or mobile terminal, and the system automatically pushes the warning information when the resistance is abnormal or the temperature rise exceeds the threshold; combined with machine learning algorithm, the service life curves of different batches of cables are clustered and analyzed to predict the reliability distribution in the whole vehicle.

[0078] It should be noted that for wire harnesses of different diameters, a quick-change V-shaped clamp is designed to improve detection efficiency; a laser displacement sensor can be used to monitor the bending radius and deformation in real time to improve detection accuracy; multiple independent detection units can be arranged on the same rack to realize batch testing.

[0079] In summary, the new energy vehicle cable wire harness detection device provided by the present application can simulate complex working conditions in vehicle operation through the synergistic effect of the six modules of the fixing, tensioning mechanism, bending mechanism 2, twisting mechanism, detection module and control system, and can comprehensively evaluate the on-state performance, insulation performance and life law of the wire harness. Through the verification of different embodiments, the device has the characteristics of high precision, high reliability and high automation, and can provide important technical support for wire harness design, manufacturing and quality control of new energy vehicle industry.

[0080] The above content is a detailed description of the present application combined with specific embodiments, and cannot be regarded as limiting the specific implementation of the present application to these descriptions. For those skilled in the art to which the present application belongs, without departing from the concept of the present application, a number of simple deductions or substitutions can be made, which should be regarded as falling within the scope of protection of the present application.

Claims

1. A cable harness detection device for new energy vehicles, characterized in that: include: Fixing mechanism: including a lower guide column and an upper guide column arranged in parallel, a wire clamp 1 is axially slidably mounted on the lower guide column via a linear bearing, and a wire clamp 2 is axially slidably mounted on the upper guide column via a linear bearing. The wire clamps 1 and 2 adopt a V-shaped clamping groove structure and are equipped with a pneumatic clamping assembly for adaptively clamping and fixing the upper and lower ends of the cable harness; Tensioning mechanism: Spring elastic bodies are respectively provided on the outer sides of the lower guide column and the upper guide column. The elastic bodies are connected to the first and second wire clamps through a connecting rod mechanism to straighten the cable harness and keep it in a taut state; Bending mechanism: It includes a rotatable servo-driven mounting plate and a pair of push rods symmetrically arranged thereon. The ends of the push rods are equipped with polyurethane V-shaped grooves, which can move along the length of the cable harness and push the cable harness to bend through reciprocating motion. The mounting plate can rotate around the center of the cable harness to change the bending direction; Torsion mechanism: arranged inside the first wire clamp, including a servo motor, a reducer and a three-jaw chuck type torsion fixture, used to drive the cable harness to reciprocate and twist around its own axis; Detection module: includes an electrical performance detection unit and an infrared temperature sensor, which is used to monitor the conductivity state, resistance change, insulation strength and temperature rise of the cable harness in real time during bending or twisting; Control system: includes a PLC controller and sensors. The controller is electrically connected to the bending mechanism, torsion mechanism and detection module, and is used to set the bending angle, torsion angle, loading frequency and number of cycles, and store and analyze the detection data.

2. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The servo motor is connected to the reducer through a coupling, and a torsion claw is installed at the output end of the reducer. The rotation of the servo motor drives the cable harness to achieve reciprocating torsion through the torsion claw.

3. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The detection module also includes an infrared temperature sensor for monitoring the temperature rise of the cable harness under high-frequency bending or torsion conditions.

4. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The control system includes a programmable logic controller that can automatically perform bending, torsion and composite loading tests according to a preset working condition curve.

5. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The first and second wire clamps adopt a pneumatic adaptive clamping structure, which can automatically adjust the clamping force according to wire harnesses of different diameters and outer skin hardness.

6. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The control system is connected to the host computer or cloud platform for communication and is used to achieve real-time uploading, storage and statistical analysis of test data.

7. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The push rod end of the bending mechanism is provided with a V-shaped or arc-shaped groove, and the inner surface of the groove is provided with anti-slip lines to prevent the wiring harness from slipping or being damaged during the bending process.

8. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The reciprocating motion mechanism adopts a linear motor or a ball screw drive to reduce wear and improve motion accuracy.

9. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The detection module is equipped with a data processing unit for generating a life curve of the cable harness in real time, including the relationship between the number of bending times and the resistance change, and the relationship between the torsion angle and the insulation strength.

10. A cable harness detection device for new energy vehicles according to claim 1, characterized in that: The device can operate in environmental chambers with different temperatures and humidity to simulate environmental stresses under actual road conditions.

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