A flexible crimping structure of a harness conductive detection clamp for an automobile

Abstract

The utility model provides a kind of elastic pressure bonding structure of automobile wire harness conduction detection clamp, belong to elastic pressure bonding structure technical field, the elastic pressure bonding structure of this automobile wire harness conduction detection clamp includes: clamp body, pressure bonding head subassembly, elastic adjusting mechanism, guide support frame and pressure sensor;The clamp body is rectangular frame structure, and the upper end surface of clamp body is equipped with rectangular opening, and the long side direction of rectangular opening is parallel with the long side direction of clamp body;The pressure bonding head subassembly includes upper pressure bonding head and lower pressure bonding head;The elastic adjusting mechanism includes spring seat, compression spring and adjusting screw rod;The guide support frame is fixedly installed on the side wall of clamp body, and guide support frame includes guide rod and sliding sleeve, solve the technical problem that existing technology exists in automobile wire harness conduction detection process wire positioning inaccuracy, contact reliability is poor and leads to inaccurate detection result.

Description

Technical Field

[0001] This utility model belongs to the field of elastic crimping structure technology, specifically, it relates to an elastic crimping structure for an automotive wiring harness continuity testing fixture. Background Technology

[0002] In modern automotive manufacturing, automotive wiring harnesses, as a crucial component of the vehicle's electrical system, directly impact the overall performance and safety of the vehicle due to their reliability in terms of conductivity. With the increasing level of automotive electronics, the number and complexity of wiring harnesses within vehicles are also constantly increasing, placing higher demands on the accuracy and efficiency of wiring harness continuity testing equipment. Traditional wiring harness continuity testing equipment primarily employs mechanical clamping, using fixed fixtures to crimp the ends of wires to achieve electrical connection with the testing circuit. However, existing fixture structures generally suffer from inaccurate crimping force control; the fixed mechanical structure cannot adapt to the crimping requirements of wires of different specifications, easily causing damage to thin wires or poor contact in thick wires. Furthermore, the wire positioning mechanism of traditional fixtures is simple, lacking precise guiding and positioning functions, resulting in poor repeatability of crimping positions and affecting the consistency and reliability of test results. Existing contact elements mostly use rigid contact methods, leading to uneven contact pressure distribution and stress concentration on the wire surface, which can damage the wire insulation layer and make it difficult to form a stable electrical connection. Furthermore, existing equipment lacks effective means to monitor the crimping process, making it impossible to grasp the crimping status in real time and to promptly detect and correct crimping abnormalities, resulting in unstable detection accuracy. These technical limitations severely restrict the automation level and detection quality of automotive wiring harness continuity testing, becoming a significant factor affecting automotive manufacturing quality control. Utility Model Content

[0003] In view of this, the elastic pressing structure of the automotive wiring harness continuity testing fixture provided by this utility model solves the technical problems of inaccurate wire positioning and poor contact reliability in the automotive wiring harness continuity testing process, which leads to inaccurate test results.

[0004] This utility model is implemented as follows:

[0005] This utility model provides an elastic crimping structure for an automotive wiring harness continuity testing fixture, comprising: a fixture body, a crimping connector assembly, an elastic adjustment mechanism, a guide support frame, and a pressure sensor; the fixture body is a rectangular frame structure, with a rectangular opening on the upper end face of the fixture body, the long side of the rectangular opening being parallel to the long side of the fixture body; the crimping connector assembly includes an upper crimping connector and a lower crimping connector, both of which are truncated cones, with the cone-shaped apex of the upper crimping connector facing downwards and the cone-shaped apex of the lower crimping connector facing upwards, and the cone-shaped apex of the upper and lower crimping connectors respectively having openings... The fixture has a V-shaped guide groove with an opening angle of 60 degrees. The elastic adjustment mechanism includes a spring seat, a compression spring, and an adjusting screw. The spring seat is fixedly installed on the bottom surface inside the fixture body. The lower end of the compression spring contacts the spring seat, and the upper end of the compression spring is connected to the bottom surface of the lower pressure connector. The adjusting screw passes through the central hole of the spring seat and is threadedly connected to the lower pressure connector. The guide support frame is fixedly installed on the side wall of the fixture body. The guide support frame includes a guide rod and a sliding sleeve. The sliding sleeve is sleeved on the guide rod and fixedly connected to the upper pressure connector to support the linear movement of the upper pressure connector along the direction of the guide rod.

[0006] The technical advantages of the elastic crimping structure of the automotive wiring harness continuity testing fixture provided by this utility model are as follows: By setting a rectangular frame structure for the fixture body and a truncated cone-shaped upper and lower crimping connector, combined with a V-shaped guide groove design, the wires of the automotive wiring harness can be effectively guided into the crimping position, ensuring precise alignment between the wires and the conductive contact pieces. The compression spring and adjusting screw in the elastic adjustment mechanism work together to provide adjustable crimping force, adapting to the crimping requirements of wires of different specifications. The guide support frame ensures the linear movement trajectory of the upper crimping connector, avoiding deviation during the crimping process and improving the stability and repeatability of the crimping quality. The fixture body is made of aluminum alloy.

[0007] Based on the above technical solution, the elastic pressing structure of the automotive wiring harness continuity testing fixture of this utility model can be further improved as follows:

[0008] The clamp body has a left guide support frame and a right guide support frame fixedly installed on its two long side walls, respectively. The left and right guide support frames are symmetrically distributed about the geometric center of the clamp body. The left guide support frame includes a left guide rod and a left sliding sleeve, and the right guide support frame includes a right guide rod and a right sliding sleeve. The left and right ends of the upper pressure joint are fixedly connected to the left and right sliding sleeves, respectively. The left and right sliding sleeves slide synchronously to ensure the horizontal posture of the upper pressure joint.

[0009] The beneficial effects of adopting the above-mentioned improved scheme are as follows: The symmetrical distribution design of the left and right guide support frames ensures that the upper crimping joint maintains a horizontal posture during the crimping process, avoiding tilting caused by unilateral force. The synchronous sliding mechanism of the left and right sliding sleeves provides dual guiding constraints, significantly improving the smoothness and accuracy of the crimping joint's movement, reducing wire damage or crimping failure caused by poor guidance, and ensuring the reliability of the crimping process.

[0010] Furthermore, the crimp connector assembly also includes a conductive contact piece, which has an elastic sheet-like structure. One end of the conductive contact piece is fixed to the bottom of the V-shaped guide groove, and the other end of the conductive contact piece is curved and extends to the opening of the V-shaped guide groove. The radius of curvature of the curved portion of the conductive contact piece is 3-8 mm, and the thickness of the conductive contact piece is 0.2-0.5 mm. The conductive contact piece is used to form an elastic contact connection with the conductor core of the automotive wiring harness.

[0011] The beneficial effects of adopting the above-mentioned improved scheme are as follows: The conductive contact piece is made of phosphor bronze, which has good elasticity and conductivity. The arc-shaped bending design allows the contact piece to adapt to wires of different diameters, forming a stable elastic contact. The curvature radius of curvature of 3 mm to 8 mm and the thickness configuration of 0.2 mm to 0.5 mm ensure that the contact piece has both sufficient elastic deformation capacity and provides stable contact pressure, achieving a reliable electrical connection and meeting the accuracy requirements of continuity detection.

[0012] Furthermore, the elastic adjustment mechanism also includes a preload nut and a locking nut, both of which are threaded onto the adjusting screw. The preload nut is located below the spring seat, and the locking nut is located below the preload nut. The preload of the compression spring is adjusted by rotating the preload nut, and the position of the preload nut is locked by rotating the locking nut. The spring constant of the compression spring is 100 N / mm to 500 N / mm, and the free length of the compression spring is 20-40 mm.

[0013] The advantages of adopting the above-mentioned improved scheme are as follows: the dual adjustment mechanism of the preload nut and the lock nut allows for precise control of the preload of the compression spring, enabling fine adjustment of the crimping force. The spring constant range of 100 N / mm to 500 N / mm accommodates the crimping force requirements of different wire specifications. The free length design of 20 mm to 40 mm ensures that the spring maintains linear characteristics within its working stroke, providing stable elastic restoring force and guaranteeing consistency in the crimping process.

[0014] Furthermore, the outer surfaces of both the upper and lower pressure connectors are provided with anti-slip textures, which are distributed in a grid pattern with a grid size of 1 mm x 1 mm. The surfaces of the upper and lower pressure connectors are plated with a nickel-chromium alloy coating with a thickness of 10 micrometers to 30 micrometers to improve the corrosion resistance and conductivity of the pressure connectors.

[0015] The beneficial effects of adopting the above-mentioned improved scheme are as follows: both the upper and lower crimp connectors are made of brass, and the grid-like anti-slip texture enhances the friction coefficient of the crimp connector surface, preventing the wires from slipping during crimping. The brass substrate combined with the nickel-chromium alloy coating ensures both good conductivity and improved corrosion resistance. The coating thickness of 10 to 30 micrometers ensures coating adhesion while providing long-term corrosion protection, extending the service life of the crimp connector, and ensuring the long-term stability of continuity testing.

[0016] Furthermore, the upper end face of the fixture body is also provided with positioning pin holes, the number of which is 4. The 4 positioning pin holes are located near the four corners of the rectangular opening, the diameter of the positioning pin holes is 6 mm, and the depth of the positioning pin holes is 10 mm. The pressure sensor is installed at the center of the bottom surface of the fixture body. The pressure sensor is connected to the lower pressure connector through a sensor bracket. The sensor bracket has a T-shaped structure. The vertical part of the sensor bracket is fixedly connected to the lower pressure connector, and the horizontal part of the sensor bracket is in contact with the pressure sensor to detect pressure changes during the pressing process.

[0017] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the precise positioning design of the four locating pin holes ensures accurate positioning of the fixture during use, avoiding poor crimping due to positional deviations. The T-shaped sensor bracket transmits the movement of the lower pressing joint to the pressure sensor, enabling real-time monitoring of the crimping force. The structural design of the sensor bracket reduces losses during force transmission, improves the accuracy of pressure detection, and provides reliable data support for crimping quality control.

[0018] Furthermore, the surface of the V-shaped guide groove wall is provided with a fine textured surface. The depth of the fine textured surface is 0.1-0.3 mm, the textured surface is distributed in a wave shape, the wavelength of the wave shape is 2-5 mm, and the amplitude of the wave shape is 0.2-0.4 mm.

[0019] The beneficial effects of the above-mentioned improvement scheme are as follows: the micro-texture within the V-shaped guide groove increases the friction with the contact surface of the wire, preventing axial slippage of the wire during crimping. The texture depth of 0.1 mm to 0.3 mm and the wavy distribution provide sufficient frictional resistance without damaging the wire insulation layer. The wavelength design of 2 mm to 5 mm and the amplitude design of 0.2 mm to 0.4 mm optimize the gripping effect of the texture, ensuring stable fixation of the wire during crimping.

[0020] Furthermore, the guide rod has a hexagonal cross-sectional shape with a side-to-side distance of 12 mm. The surface of the guide rod is provided with straight guide grooves that extend along the length of the guide rod. There are three straight guide grooves, which are distributed at equal angles on the circumference of the guide rod.

[0021] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the hexagonal cross-section guide rod design has better anti-rotation capability compared to the circular cross-section, preventing the sliding sleeve from rotating on the guide rod. The 12 mm distance between opposite sides provides sufficient structural strength, and the three equally angled linear guide grooves enhance guiding accuracy. The extension design of the guide grooves along the length direction ensures consistent guiding throughout the entire stroke, improving the straightness of the crimping joint movement and repeatability.

[0022] Furthermore, the inner hole shape of the sliding sleeve matches the cross-sectional shape of the guide rod. The distance between opposite sides of the hexagon in the inner hole of the sliding sleeve is 0.1-0.3 mm larger than the distance between opposite sides of the hexagon in the guide rod. The inner surface of the sliding sleeve is provided with protrusions that match the straight guide groove. There are 3 protrusions, and the 3 protrusions are evenly distributed at angles in the circumferential direction of the inner hole of the sliding sleeve.

[0023] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the precise fit between the inner hole of the sliding sleeve and the cross-section of the guide rod, with a clearance design of 0.1 mm to 0.3 mm, ensures smooth sliding while controlling radial clearance. The fit between the three equally angled inner hole protrusions and the guide groove of the guide rod forms multi-point constraints, significantly improving the stability of the guide. The precise control of the fit clearance reduces vibration and noise during movement, ensuring the smoothness of the crimping process.

[0024] Furthermore, the upper surface of the spring seat is provided with an annular groove. The inner diameter of the annular groove is the outer diameter of the compression spring plus 2 mm, and the depth of the annular groove is 5-10 mm. The annular groove is used to position the lower end of the compression spring. The thread specification of the adjusting screw is M8 multiplied by 1.25 mm, and the effective thread length of the adjusting screw is 50-80 mm.

[0025] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the annular groove design on the spring seat ensures accurate positioning of the compression spring and prevents lateral displacement of the spring during the force process. The design of the groove inner diameter being 2 mm larger than the spring outer diameter ensures both the free deformation of the spring and provides necessary guiding constraints. The M8 multiplied by 1.25 mm thread specification and the effective thread length of 50 mm to 80 mm provide sufficient adjustment range and connection strength, ensuring the reliability and durability of the adjustment mechanism.

[0026] Compared with existing technologies, the beneficial effects of the elastic crimping structure of the automotive wiring harness continuity testing fixture provided by this utility model are as follows: This utility model effectively solves the key technical problems in automotive wiring harness continuity testing through innovative elastic crimping structure design. The rectangular frame fixture body, combined with the truncated cone crimping head and V-shaped guide groove design, achieves precise guidance and positioning of the wire, significantly improving the accuracy of the crimping position. The multi-stage adjustment system composed of compression spring, adjusting screw, pre-tightening nut, and locking nut in the elastic adjustment mechanism can precisely control the crimping force according to the characteristics of wires of different specifications, ensuring consistent pressure characteristics for each crimp. The arc-shaped bending design and reasonable material thickness configuration of the phosphor bronze conductive contact piece enable the contact piece to adapt to the contact requirements of wires of different diameters, forming a stable and reliable electrical connection. The symmetrical arrangement of the double-sided guide support frame and the hexagonal guide rod combined with the precision sliding sleeve guide mechanism ensure the high precision linearity and repeatability of the crimping head movement. The surface treatment of the grid-like anti-slip texture and nickel-chromium alloy coating not only improves the gripping force but also enhances the corrosion resistance. The integrated design of the pressure sensor enables real-time monitoring of the crimping process, providing data support for quality control. The overall structural design considers the feasibility of manufacturing processes and ease of maintenance, demonstrating promising industrial application prospects and economic benefits. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is an example diagram of the elastic crimping structure of an automotive wiring harness continuity testing fixture;

[0029] Figure 2 A perspective view of the elastic crimping structure of an automotive wiring harness continuity testing fixture;

[0030] Figure 3 for Figure 2 Enlarged view of section A in the middle;

[0031] Figure 4 An example diagram of a sliding sleeve with an elastic pressing structure for an automotive wiring harness continuity testing fixture;

[0032] The attached diagram lists the components represented by each number as follows:

[0033] 10. Fixture body; 20. Press fitting assembly; 21. Upper press fitting; 22. Lower press fitting; 30. Elastic adjustment mechanism; 31. Spring seat; 32. Compression spring; 33. Adjusting screw; 40. Guide support frame. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0035] like Figures 1-3 The diagram shown is an example of an elastic crimping structure for an automotive wiring harness continuity testing fixture provided by this utility model. It includes: a fixture body 10, a crimping connector assembly 20, an elastic adjustment mechanism 30, a guide support frame 40, and a pressure sensor. The fixture body 10 has a rectangular frame structure, with a rectangular opening on its upper surface. The long side of the rectangular opening is parallel to the long side of the fixture body 10. The crimping connector assembly 20 includes an upper crimping connector 21 and a lower crimping connector 22. Both the upper crimping connector 21 and the lower crimping connector 22 are truncated cones. The conical apex of the upper crimping connector 21 faces downwards, and the conical apex of the lower crimping connector 22 faces upwards. The conical apexes of the upper crimping connector 21 and the lower crimping connector 22 are respectively... The fixture is equipped with a V-shaped guide groove with an opening angle of 60 degrees. The elastic adjustment mechanism 30 includes a spring seat 31, a compression spring 32, and an adjusting screw 33. The spring seat 31 is fixedly installed on the bottom surface inside the fixture body 10. The lower end of the compression spring 32 contacts the spring seat 31, and the upper end of the compression spring 32 is connected to the bottom surface of the lower pressure connector 22. The adjusting screw 33 passes through the central hole of the spring seat 31 and is threadedly connected to the lower pressure connector 22. The guide support frame 40 is fixedly installed on the side wall of the fixture body 10. The guide support frame 40 includes a guide rod and a sliding sleeve. The sliding sleeve is sleeved on the guide rod and fixedly connected to the upper pressure connector 21 to support the linear movement of the upper pressure connector 21 along the direction of the guide rod.

[0036] The specific operation or usage method is as follows: Before use, first adjust the pre-compression amount of the compression spring by rotating the pre-tightening nut on the adjusting screw according to the specifications and material characteristics of the automotive wiring harness wire to be tested, and set appropriate crimping force parameters. Then, fix the position of the pre-tightening nut with the locking nut. Place the fixture body on the testing workbench, and achieve precise positioning of the fixture by cooperating with the positioning pin of the workbench through the positioning pin hole. The operator strips the insulation layer from the end of the automotive wiring harness wire, exposing the wire core, and then places the processed wire into the V-shaped guide groove of the lower crimping connector. Under the guidance of the V-shaped guide groove, the wire is automatically positioned to the crimping center position. Start the crimping mechanism, and the upper crimping connector moves downward along a straight trajectory under the constraint of the guide support frame. When the upper crimping connector contacts the wire, the compression spring is further compressed, and the resulting elastic force is transmitted to the wire through the lower crimping connector, realizing the crimping action. During the crimping process, the phosphor bronze conductive contact piece forms a tight contact with the wire core under the action of elastic force, establishing a stable electrical connection path. The pressure sensor monitors the force changes during the crimping process in real time via a sensor bracket. When the crimping force reaches the set value, the system indicates that crimping is complete. After crimping, a continuity test is performed on the wiring harness through a detection circuit to verify the reliability of the electrical connection. After the test is completed, the crimping mechanism is released, and the upper crimping connector automatically returns to its initial position under the action of spring force, allowing the tested wiring harness wires to be removed. The entire operation process is simple and efficient, and standardized operating procedures ensure the consistency and repeatability of test results, meeting the testing needs of large-volume automotive wiring harnesses.

[0037] like Figure 4 As shown, in the above technical solution, a left guide support frame and a right guide support frame are fixedly installed on the two long side walls of the clamp body 10, respectively. The left guide support frame and the right guide support frame are symmetrically distributed about the geometric center of the clamp body 10. The left guide support frame includes a left guide rod and a left sliding sleeve, and the right guide support frame includes a right guide rod and a right sliding sleeve. The left and right ends of the upper pressure joint 21 are fixedly connected to the left sliding sleeve and the right sliding sleeve, respectively. The left sliding sleeve and the right sliding sleeve slide synchronously to ensure the horizontal posture of the upper pressure joint 21.

[0038] Installation positions of the guide support brackets: Left guide support bracket: Secured to the inner surface of the left long side wall using two M5 countersunk screws, locking from the inside out, with the screw heads not protruding from the outer wall. Right guide support bracket: Symmetrically fixed to the inner surface of the right long side wall. The entire bracket is "attached" to the inner side wall, without encroaching on external space or protruding beyond the outer surface.

[0039] The inner hole of the sliding sleeve is fitted onto the guide rod, with only a 0.2 mm gap between the outer surface of the sleeve and the outer surface of the guide rod; the sleeve can slide up and down along the rod, but is completely "enclosed" by the rod in the radial direction.

[0040] Furthermore, in the above technical solution, the crimp connector assembly 20 also includes a conductive contact piece. The conductive contact piece has an elastic sheet-like structure. One end of the conductive contact piece is fixed to the bottom of the V-shaped guide groove, and the other end of the conductive contact piece is curved and extends to the opening of the V-shaped guide groove. The radius of curvature of the curved portion of the conductive contact piece is 3-8 mm, and the thickness of the conductive contact piece is 0.2-0.5 mm. The conductive contact piece is used to form an elastic contact connection with the conductor core of the automotive wiring harness.

[0041] Furthermore, in the above technical solution, the elastic adjustment mechanism 30 also includes a preload nut and a locking nut. Both the preload nut and the locking nut are threaded onto the adjusting screw. The preload nut is located below the spring seat, and the locking nut is located below the preload nut. The preload of the compression spring is adjusted by rotating the preload nut, and the position of the preload nut is locked by rotating the locking nut. The spring constant of the compression spring is 100 N / mm to 500 N / mm, and the free length of the compression spring is 20-40 mm.

[0042] The elastic adjustment mechanism is fixed directly below the center of the opening, and its compression spring transmits the upward thrust to the crimping assembly through the lower crimping joint; the upper and lower crimping areas of the crimping joint assembly are always kept within the projection range of the rectangular opening.

[0043] Furthermore, in the above technical solution, the outer surfaces of both the upper pressure connector 21 and the lower pressure connector 22 are provided with anti-slip textures, which are distributed in a grid pattern with a grid size of 1 mm x 1 mm. The surfaces of the upper pressure connector 21 and the lower pressure connector 22 are plated with a nickel-chromium alloy coating with a thickness of 10 micrometers to 30 micrometers to improve the corrosion resistance and conductivity of the pressure connectors.

[0044] Furthermore, in the above technical solution, the upper end face of the fixture body 10 is also provided with positioning pin holes. There are four positioning pin holes, which are located near the four corners of the rectangular opening. The diameter of the positioning pin holes is 6 mm and the depth of the positioning pin holes is 10 mm. The pressure sensor is installed at the center of the bottom surface of the fixture body 10. The pressure sensor is connected to the lower pressure connector 22 through a sensor bracket. The sensor bracket has a T-shaped structure. The vertical part of the sensor bracket is fixedly connected to the lower pressure connector 22, and the horizontal part of the sensor bracket is in contact with the pressure sensor to detect pressure changes during the pressing process.

[0045] Furthermore, in the above technical solution, the surface of the V-shaped guide groove wall is provided with fine concave and convex textures. The depth of the fine concave and convex textures is 0.1-0.3 mm, the fine concave and convex textures are distributed in a wavy shape, the wavelength of the wavy shape is 2-5 mm, and the amplitude of the wavy shape is 0.2-0.4 mm.

[0046] Furthermore, in the above technical solution, the cross-sectional shape of the guide rod is hexagonal, the distance between opposite sides of the hexagon is 12 mm, and the surface of the guide rod is provided with straight guide grooves. The straight guide grooves extend along the length direction of the guide rod, and there are 3 straight guide grooves. The 3 straight guide grooves are distributed at equal angles in the circumferential direction of the guide rod.

[0047] Furthermore, in the above technical solution, the inner hole shape of the sliding sleeve matches the cross-sectional shape of the guide rod. The distance between opposite sides of the hexagon in the inner hole of the sliding sleeve is 0.1-0.3 mm larger than the distance between opposite sides of the hexagon in the guide rod. The inner surface of the sliding sleeve is provided with protrusions that match the straight guide groove. There are 3 protrusions, and the 3 protrusions are evenly distributed at angles in the circumferential direction of the inner hole of the sliding sleeve.

[0048] Furthermore, in the above technical solution, the upper surface of the spring seat 31 is provided with an annular groove. The inner diameter of the annular groove is the outer diameter of the compression spring plus 2 mm, and the depth of the annular groove is 5-10 mm. The annular groove is used to position the lower end of the compression spring. The thread specification of the adjusting screw is M8 multiplied by 1.25 mm, and the effective thread length of the adjusting screw is 50-80 mm.

[0049] First Embodiment: The automotive wiring harness continuity testing fixture in this embodiment adopts a modular design concept. The fixture body is made of 6061 aluminum alloy, which has good mechanical strength and corrosion resistance. The fixture body has external dimensions of 200 mm in length, 150 mm in width, and 100 mm in height, with a wall thickness of 8 mm to ensure sufficient structural rigidity. The rectangular opening has dimensions of 120 mm in length and 80 mm in width, with chamfered edges of 2 mm to prevent sharp edges from causing injury to operators. Both the upper and lower pressure connectors are made of H62 brass, with a large end diameter of 25 mm, a small end diameter of 15 mm, a cone height of 12 mm, and a cone half-angle of 30 degrees. The V-shaped guide groove has a depth of 8 mm and a bottom arc radius of 1 mm to ensure good fit with wires of different diameters. The conductive contact piece is made of QSn4-3 phosphor bronze, with a thickness of 0.3 mm, a width of 5 mm, a radius of curvature of 5 mm for the curved section, and an elastic modulus of 110 GPa, ensuring good elastic recovery performance. The compression spring is made of high-quality spring steel wire, with an outer diameter of 18 mm, an inner diameter of 12 mm, a wire diameter of 3 mm, a free length of 30 mm, a spring constant of 200 N / mm, and a surface treated with anti-corrosion galvanizing. The adjusting screw is made of 45# steel, with a surface hardening hardness of HRC45-50, ensuring wear resistance of the threads. The guide rod is made of stainless steel, with a length of 80 mm, a hexagonal side-to-side distance of 12 mm, and a surface roughness of Ra0.8, ensuring smooth sliding. The sliding sleeve is made of bronze, with an inner hexagonal side-to-side distance of 12.2 mm and a clearance controlled at 0.1 mm, ensuring guiding accuracy. The pressure sensor is a strain gauge type, with a measurement range of 0-500 Newtons, an accuracy class of 0.5, and an output signal of 4-20 mA, facilitating connection to control systems. During use, the fixture can accommodate automotive wires with diameters ranging from 0.5 mm to 3.0 mm, and the crimping force can be precisely adjusted from 50 Newtons to 300 Newtons. Its compact structure, convenient operation, and simple maintenance make it suitable for mass production on automotive manufacturing lines. Precise manufacturing processes and strict quality control ensure consistent performance across each fixture, providing reliable technical support for automotive wiring harness continuity testing.

[0050] Second Embodiment: This embodiment is an improved solution based on the first embodiment, addressing the requirements for high-precision wire inspection. A precision positioning block is added within the V-shaped guide groove. The positioning block is made of hard alloy material and has a wedge-shaped structure with a wedge angle of 45 degrees. It is connected to the bottom of the guide groove via a spring loading mechanism, automatically adjusting its position according to the wire diameter for more precise radial positioning. The conductive contact piece is improved to a double-layer structure design. The inner layer is made of silver alloy material with a thickness of 0.1 mm, while the outer layer remains made of phosphor bronze material with a thickness of 0.2 mm. The double-layer structure is combined using diffusion welding technology, ensuring both good conductivity and sufficient mechanical strength. The elastic adjustment mechanism includes a fine-tuning device comprising a fine-tuning screw and a differential thread structure. The fine-tuning screw has a pitch of 0.25 mm, achieving spring pre-compression adjustment with a precision of 0.05 mm through differential principle, significantly improving the control accuracy of the crimping force. The guide support frame replaces the original sliding sleeve structure with a linear bearing guide system. The linear bearings have a precision grade of P5, and the radial clearance is controlled within 5 micrometers, significantly improving guiding accuracy and smoothness of movement. The pressure sensor has been upgraded to a high-precision force sensor with a resolution of 0.1 Newtons, which, together with a digital display instrument, enables real-time display and data recording of the crimping force. This improved solution is particularly suitable for aerospace-grade automotive wiring harness testing applications with extremely high continuity detection accuracy requirements, and can meet even more stringent quality control standards.

[0051] Specifically, the principle of this invention is as follows: This invention employs the principle of elastic crimping, achieving precise control and stable output of the crimping force through a precisely designed elastic adjustment mechanism. The compression spring, as an elastic element, provides a constant crimping force. Its elastic characteristics ensure stable contact pressure during conductor deformation, avoiding poor contact or excessive compression caused by rigid crimping. The mechanical adjustment system, consisting of an adjusting screw and a pre-tightening nut, finely adjusts the crimping force by changing the spring's pre-compression, meeting the crimping requirements of different conductor specifications. The V-shaped guide groove's geometric design is based on the principle of natural conductor fall. The guiding effect of the conical structure allows the conductor to automatically enter the optimal crimping position under the combined action of gravity and guiding force, significantly improving positioning accuracy. The design of the frustum-shaped crimping joint fully utilizes the wedge crimping principle; the gradually increasing contact area ensures uniform pressure distribution, avoiding stress concentration. The elastic deformation characteristics of the phosphor bronze conductive contact piece enable it to adapt to minor unevenness on the conductor surface, forming multi-point stable contact and greatly improving contact reliability. The symmetrical guiding system, composed of a double-sided guide support structure, ensures the stability of the crimping joint during movement based on the principle of mechanical balance. The polygonal cross-section design of the hexagonal guide rod effectively prevents the rotation of the sliding sleeve, ensuring the straightness of the movement trajectory. The fine textured surface increases the coefficient of friction, preventing wire slippage during crimping and ensuring accurate crimping position. The integrated design of the pressure sensor enables real-time monitoring of the crimping process, providing data support for quality control through the conversion of mechanical signals, forming a closed-loop control system.

Claims

1. An elastic pressing structure for an automotive wiring harness continuity testing fixture, characterized in that, include: The fixture comprises a clamp body, a crimping connector assembly, an elastic adjustment mechanism, a guide support frame, and a pressure sensor. The clamp body has a rectangular frame structure with a rectangular opening on its upper surface, the long side of which is parallel to the long side of the clamp body. The crimping connector assembly includes an upper crimping connector and a lower crimping connector, both of which are truncated cones. The cone-shaped apex of the upper crimping connector faces downwards, and the cone-shaped apex of the lower crimping connector faces upwards. V-shaped guide grooves are formed at the cone-shaped apex of both the upper and lower crimping connectors, with an opening angle of 6°. 0 degrees; The elastic adjustment mechanism includes a spring seat, a compression spring, and an adjusting screw. The spring seat is fixedly installed on the bottom surface inside the fixture body. The lower end of the compression spring contacts the spring seat, and the upper end of the compression spring is connected to the bottom surface of the lower pressure connector. The adjusting screw passes through the central hole of the spring seat and is threadedly connected to the lower pressure connector. The guide support frame is fixedly installed on the side wall of the fixture body. The guide support frame includes a guide rod and a sliding sleeve. The sliding sleeve is sleeved on the guide rod and fixedly connected to the upper pressure connector to support the linear movement of the upper pressure connector along the direction of the guide rod.

2. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 1, characterized in that, A left guide support frame and a right guide support frame are fixedly installed on the two long side walls of the clamp body, respectively. The left guide support frame and the right guide support frame are symmetrically distributed about the geometric center of the clamp body. The left guide support frame includes a left guide rod and a left sliding sleeve, and the right guide support frame includes a right guide rod and a right sliding sleeve. The left and right ends of the upper pressure joint are fixedly connected to the left sliding sleeve and the right sliding sleeve, respectively. The left sliding sleeve and the right sliding sleeve slide synchronously to ensure the horizontal posture of the upper pressure joint.

3. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 2, characterized in that, The crimp connector assembly also includes a conductive contact piece, which has an elastic sheet-like structure. One end of the conductive contact piece is fixed to the bottom of the V-shaped guide groove, and the other end of the conductive contact piece is curved and extends to the opening of the V-shaped guide groove. The radius of curvature of the curved portion of the conductive contact piece is 3-8 mm, and the thickness of the conductive contact piece is 0.2-0.5 mm. The conductive contact piece is used to form an elastic contact connection with the conductor core of the automotive wiring harness.

4. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 3, characterized in that, The elastic adjustment mechanism also includes a preload nut and a locking nut, both of which are threaded onto the adjusting screw. The preload nut is located below the spring seat, and the locking nut is located below the preload nut. The preload of the compression spring is adjusted by rotating the preload nut, and the position of the preload nut is locked by rotating the locking nut. The spring constant of the compression spring is 100 N / mm to 500 N / mm, and the free length of the compression spring is 20-40 mm.

5. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 4, characterized in that, The outer surfaces of both the upper and lower pressure connectors are provided with anti-slip textures, which are distributed in a grid pattern with a grid size of 1 mm by 1 mm. The surfaces of both the upper and lower pressure connectors are plated with a nickel-chromium alloy coating with a thickness of 10 micrometers to 30 micrometers to improve the corrosion resistance and conductivity of the pressure connectors.

6. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 5, characterized in that, The upper surface of the fixture body is also provided with positioning pin holes. There are four positioning pin holes, which are located near the four corners of the rectangular opening. The diameter of the positioning pin holes is 6 mm and the depth of the positioning pin holes is 10 mm. The pressure sensor is installed at the center of the bottom surface of the fixture body. The pressure sensor is connected to the lower pressure connector through a sensor bracket. The sensor bracket has a T-shaped structure. The vertical part of the sensor bracket is fixedly connected to the lower pressure connector, and the horizontal part of the sensor bracket is in contact with the pressure sensor to detect pressure changes during the pressing process.

7. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 6, characterized in that, The surface of the V-shaped guide groove is provided with a fine textured surface. The depth of the fine textured surface is 0.1-0.3 mm, the textured surface is distributed in a wave shape, the wavelength of the wave shape is 2-5 mm, and the amplitude of the wave shape is 0.2-0.4 mm.

8. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 7, characterized in that, The guide rod has a hexagonal cross-section with a side-to-side distance of 12 mm. The surface of the guide rod is provided with straight guide grooves that extend along the length of the guide rod. There are three straight guide grooves that are evenly distributed at an angle along the circumference of the guide rod.

9. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 8, characterized in that, The inner hole shape of the sliding sleeve matches the cross-sectional shape of the guide rod. The distance between opposite sides of the hexagon in the inner hole of the sliding sleeve is 0.1-0.3 mm larger than the distance between opposite sides of the hexagon in the guide rod. The inner surface of the sliding sleeve is provided with protrusions that match the straight guide groove. There are 3 protrusions, and the 3 protrusions are evenly distributed at an angle in the circumferential direction of the inner hole of the sliding sleeve.

10. The elastic pressing structure of the automotive wiring harness continuity testing fixture according to claim 9, characterized in that, The upper surface of the spring seat is provided with an annular groove. The inner diameter of the annular groove is the outer diameter of the compression spring plus 2 mm, and the depth of the annular groove is 5-10 mm. The annular groove is used to position the lower end of the compression spring. The thread specification of the adjusting screw is M8 multiplied by 1.25 mm, and the effective thread length of the adjusting screw is 50-80 mm.

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