A calibration device for bidirectional loading of a steering tie rod

Abstract

The present application relates to the technical fields of bidirectional loading calibration device, and discloses a kind of steering drag link tension-compression bidirectional loading calibration device, comprising: two-way loading machine, and two drag link force modules are symmetrically provided with detection mechanism in it;Detection mechanism is made of upper box, lower box and two groups of automatic patch claw, each group of automatic patch claw includes multiple independent automatic patch claw, and two groups of automatic patch claw are fixed in the inner wall of upper box and lower box respectively, and the working end of all automatic patch claw is towards steering drag link that is through upper box and lower box, and the automatic patch claw in upper box and lower box is staggered distribution to realize full circumferential wrapping;The end of automatic patch claw is fixedly provided with embracing arm, strain gauge is installed in the center position of embracing arm, and suspension module and glue spraying module are integrated in its side wall;The present application is positioned and pasted by setting automatic patch claw and embracing arm, cooperate suspension module and glue spraying module, realizes the automation of strain gauge.

Description

Technical Field

[0001] This invention relates to the field of bidirectional loading calibration devices, and more specifically, to a bidirectional loading calibration device for a steering tie rod. Background Technology

[0002] As a key force-transmitting component of the automotive steering system, the strength and durability of the steering tie rod are directly related to the vehicle's driving safety. In the design, production and quality inspection of the steering tie rod, in order to accurately obtain the stress distribution when it is subjected to tensile and compressive loads, it is usually necessary to use resistance strain gauges to perform stress tests on the steering tie rod.

[0003] The process of applying and calibrating strain gauges for steering tie rods mainly relies on manual operation, which has the following significant technical defects and pain points: First, manual strain gauge application is inefficient and inconsistent. Steering tie rods are typically cylindrical members. To achieve full-circumferential stress monitoring, multiple strain gauges often need to be attached to different positions along the circumference of the rod. Manual operation makes it difficult to ensure that the attachment position, angle, and adhesive layer thickness of each strain gauge are completely consistent, which directly introduces human error and reduces the reliability of the test data. To address this, we propose a bidirectional tensile and compressive loading calibration device for steering tie rods. Summary of the Invention

[0004] This invention provides a bidirectional loading calibration device for steering tie rods, which solves the technical problem in related technologies where manual operation makes it difficult to ensure that the pasting position, angle and adhesive layer thickness of each strain gauge are completely consistent, which directly introduces human error and reduces the reliability of test data.

[0005] This invention provides a bidirectional loading calibration device for steering tie rods, comprising: a bidirectional loader, wherein detection mechanisms are symmetrically arranged within the two tie rod force application modules; The testing mechanism consists of an upper box, a lower box, and two sets of automatic patching claws. Each set of automatic patching claws contains multiple independent automatic patching claws, and the two sets of automatic patching claws are fixed to the inner walls of the upper box and the lower box respectively. The working ends of all automatic patching claws are directed towards the steering rod that runs through the upper box and the lower box, and the automatic patching claws in the upper box and the lower box are spatially staggered to achieve full circumferential wrapping. The end of the automatic patching claw is fixedly equipped with a circumferential arm, and a strain gauge is installed at the center of the circumferential arm. The side wall integrates a suspension module and a glue spraying module. The suspension module adopts an elastic structure, and the strain gauges are suspended in the center of the circumferential arm through mechanical interlocking. When the automatic patching claw performs the extension-closing action, the suspension module releases the strain gauge and makes it automatically wrap around the steering tie rod. The glue spraying module simultaneously sprays quick-drying glue onto the surface of the steering tie rod to achieve the bonding and fixing of the strain gauge. The testing facility also integrates a data acquisition module, which communicates with the host computer wirelessly to collect strain data from strain gauges and load data from the bidirectional loader in real time, and performs linear fitting based on the least squares method to generate calibration coefficients.

[0006] Furthermore, the lower box is fixed on the detection area end face of the bidirectional loader, the upper box is rotatably mounted on the lower box, and the steering tie rod passes through the center position of the closed upper and lower boxes, with the steering tie rod just between the upper and lower sets of automatic patching claws.

[0007] Furthermore, the automatic placement claw includes a circling arm fixed to the end of the claw. The closed circling arm is elliptical and has a diameter larger than the steering tie rod. Both the upper and lower sets of automatic placement claws circulate around the outside of the steering tie rod from both the upper and lower directions.

[0008] Furthermore, a power supply box is fixedly installed on the upper wall of the upper box. The power supply box is an integrated device, which contains a pump body that supplies the specified glue to the glue spraying module and pre-stored glue.

[0009] Furthermore, the glue spraying module includes a glue spraying tube, which is fixed to the outer wall of the arm. The glue spraying tube has multiple outlet ends, each with a glue spray nozzle. Several glue spray nozzles are embedded side by side in the arm, and the glue spraying direction of all the nozzles is towards the center of the arm, for spraying glue when the automatic patching claw moves downward to hug the steering lever.

[0010] Furthermore, the suspension module includes a take-up drum, which is also fixed to the outer wall of the arm. The inside of the take-up drum is equipped with multiple elastic take-up wheels, and each elastic take-up wheel is connected to the take-up drum through a coil spring. Each elastic take-up wheel is fixed with a pull wire, and a winding tension is always applied to the pull wire.

[0011] Furthermore, side pull plates are fixedly installed on both sides of the strain gauge near the circumferential arm, and the side pull plates are arrayed with binding holes. Each strain gauge wire corresponds to a binding hole and is tightly bound. The strain gauge wires have no elasticity.

[0012] Furthermore, the automatic patching claw first moves the open wrapping arm toward the steering tie rod, then controls the wrapping arm to gradually close, while simultaneously spraying adhesive onto the steering tie rod through the adhesive nozzle, then presses the strain gauge onto the steering tie rod, and finally controls the wrapping arm to completely close, so that the strain gauge is fully wrapped.

[0013] Furthermore, the detection surface of the strain gauge is provided with two cutting wires, which are closely attached to the inner wall of the strain gauge. The two cutting wires run along the edge of the strain gauge at right angles, and the right angles of the two cutting wires are obliquely opposite each other. At the same time, a tension rope is fixedly installed at the right angle point of the cutting wires. The tension rope is retracted in the tension rope chamber, which is opened in the side tension plate.

[0014] Furthermore, a miniature controllable push rod is fixedly installed on both sides of the automatic patching claw. The telescopic arm of the miniature controllable push rod is fixedly connected to a strip removal pull line. The two strip removal pull lines are respectively connected to one end of each of the two cutting wires. After the test is completed, the cutting wire is pulled by the miniature controllable push rod, so that the cutting wire is straightened into a diagonal straight line. This process is used to cut the glue tightly against the steering tie rod.

[0015] The beneficial effects of this invention are as follows: This invention achieves automated positioning and bonding of strain gauges by incorporating an automatic bonding claw and a gripping arm, along with a suspension module and a glue spraying module. Compared to manual bonding, this device can precisely control the position and bonding force of the strain gauges, eliminating human error and significantly improving bonding consistency and test data reliability. By setting two sets of automatic patching claws arranged in a spatially staggered manner within the upper and lower boxes, full circumferential wrapping of the steering tie rod is achieved. This design can more comprehensively capture the stress distribution of the rod under complex stress conditions, effectively avoiding measurement blind spots caused by patching on only one side. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the upper and lower boxes of the present invention from the left view. Figure 3 This is a schematic diagram of the automatic patching claw structure from the left side of the present invention; Figure 4 This is a schematic diagram of the automatic patching claw structure of the present invention; Figure 5 This is a schematic diagram of the strain gauge structure of the present invention; Figure 6 This is a schematic diagram of the internal structure of the take-up drum of the present invention; Figure 7 This is a schematic diagram of the lower wall structure of the strain gauge of the present invention; Figure 8 This is the invention Figure 7 Enlarged view of point A in the middle; Figure 9 This is a schematic diagram of the rubber cutting wire straightening structure of the present invention.

[0017] In the diagram: 11. Bidirectional loader; 2. Detection mechanism; 21. Upper box; 22. Lower box; 23. Automatic patching claw; 24. Hugging arm; 25. Take-up reel; 251. Elastic take-up reel; 26. Glue spray tube; 27. Strain gauge; 271. Side pull plate; 272. Glue cutting wire; 273. Elastic rope chamber; 274. Wire pulling elastic rope; 28. Miniature controllable push rod; 29. ​​Patch removal pull line; 31. Glue nozzle; 32. Patch pulling wire; 4. Power supply box. Detailed Implementation

[0018] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, features described in some examples may be combined in other examples.

[0019] like Figures 1-9 As shown, a steering tie rod tension-compression bidirectional loading calibration device includes: a bidirectional loader 11, wherein detection mechanisms 2 are symmetrically arranged in the two tie rod force application modules; The testing mechanism 2 consists of an upper box 21, a lower box 22, and two sets of automatic patching claws 23. Each set of automatic patching claws 23 contains multiple independent automatic patching claws 23, and the two sets of automatic patching claws 23 are fixed to the inner walls of the upper box 21 and the lower box 22 respectively. The working ends of all automatic patching claws 23 are directed towards the steering rod that passes through the upper box 21 and the lower box 22, and the automatic patching claws 23 in the upper box 21 and the lower box 22 are spatially staggered to achieve full circumferential wrapping. The end of the automatic patching claw 23 is fixedly provided with a circumferential arm 24, and a strain gauge 27 is installed at the center of the circumferential arm 24. The side wall of the strain gauge 24 is integrated with a suspension module and a glue spraying module. The suspension module adopts an elastic structure, and the strain gauge 27 is suspended in the center of the circumferential arm 24 by mechanical interlocking. When the automatic patching claw 23 performs the extension-closing action, the suspension module releases the strain gauge 27 and makes it automatically wrap around the steering tie rod. The glue spraying module simultaneously sprays quick-drying glue onto the surface of the steering tie rod to achieve the bonding and fixing of the strain gauge 27. The testing unit 2 also integrates a data acquisition module, which communicates with the host computer wirelessly to acquire strain data of strain gauge 27 and load data of bidirectional loader 11 in real time, and performs linear fitting based on the least squares method to generate calibration coefficients.

[0020] The lower box 22 is fixed on the detection area end face of the bidirectional loader 11, and the upper box 21 is rotatably mounted on the lower box 22. The steering rod passes through the center position of the closed upper box 21 and lower box 22, and the steering rod is just between the upper and lower automatic patching claws 23.

[0021] The automatic placement claw 23 includes a circling arm 24 fixed to the end of the claw. The closed circling arm 24 is elliptical and has a diameter larger than the steering pull rod. The upper and lower sets of automatic placement claws 23 are both circling the outside of the steering pull rod from the upper and lower directions.

[0022] A power supply box 4 is fixedly installed on the upper wall of the upper box 21. The power supply box 4 is an integrated device. The power supply box 4 contains a pump body that supplies the specified glue to the glue spraying module and pre-stored glue.

[0023] The glue spraying module includes a glue spraying tube 26, which is fixed to the outer wall of the arm 24. The glue spraying tube 26 has multiple outlet ends, each of which is equipped with a glue spray nozzle 31. Several glue spray nozzles 31 are embedded side by side in the arm 24. The glue spraying direction of all glue spray nozzles 31 is towards the center of the arm 24, which is used to spray glue when the automatic patching claw 23 moves downward to hug the steering lever.

[0024] The suspension module includes a take-up drum 25, which is also fixed to the outer wall of the arm 24. The inside of the take-up drum 25 is provided with multiple elastic take-up wheels 251, and each elastic take-up wheel 251 is connected to the take-up drum 25 via a coil spring. Each elastic take-up wheel 251 is fixed with a pull wire 32, and a winding tension is always applied to the pull wire 32.

[0025] Side pull plates 271 are fixedly installed on both sides of the strain gauge 27 near the arm 24, and the side pull plates 271 are arrayed with binding holes. Each strain gauge wire 32 corresponds to a binding hole and is tied tightly. The strain gauge wire 32 has no elasticity.

[0026] The automatic patching claw 23 first moves the open wrapping arm 24 toward the steering tie rod, then controls the wrapping arm 24 to gradually close, while simultaneously spraying glue onto the steering tie rod through the glue nozzle 31, then presses the strain gauge 27 onto the steering tie rod, and finally controls the wrapping arm 24 to completely close, so that the strain gauge 27 is fully wrapped.

[0027] The detection surface of the strain gauge 27 is provided with two cutting wires 272, which are closely attached to the inner wall of the strain gauge 27. The two cutting wires 272 run along the edge of the strain gauge 27 at right angles, and the right angles of the two cutting wires 272 are obliquely opposite each other. At the same time, a tension rope 274 is fixedly installed at the right angle point of the cutting wires 272. The tension rope 274 is retracted in the tension rope chamber 273, which is opened in the side pull plate 271.

[0028] Both sides of the automatic patching claw 23 are fixedly equipped with a miniature controllable push rod 28. The telescopic arm of the miniature controllable push rod 28 is fixedly connected to a patch removal pull line 29. The two patch removal pull lines 29 are respectively connected to one end of each of the two cutting wires 272. After the test is completed, the cutting wires 272 are pulled by the miniature controllable push rod 28, so that the cutting wires 272 are straightened into a diagonal straight line. This process is used to cut the glue tightly against the steering tie rod.

[0029] Its specific workflow and internal mechanism are as follows: Initial preparation and positioning phase: Before the device is started, the lower box 22 is fixed on the end face of the detection area of ​​the bidirectional loader 11. The operator passes the steering tie rod to be calibrated through the preset center slot of the lower box 22. Then, the upper box 21 is closed by the rotation mechanism, so that it is engaged with the lower box 22. At this time, the steering tie rod is exactly at the center position of the upper box 21 and the lower box 22, and is fully wrapped by the two sets of automatic patching claws 23 that are spatially staggered.

[0030] Automatic placement claw 23 extension and encircling action phase: Action logic: The system issues a command, and the two sets of automatic placement claws 23 in the upper box 21 and the lower box 22 simultaneously perform the extension-closing claw action.

[0031] Initially, the retaining arm 24 is in the open state. The automatic patching claw 23 first drives the open retaining arm 24 to move radially toward the steering tie rod.

[0032] The coordinated positioning stage of adhesive spraying and strain gauge 27: As the arm 24 gradually retracts, the adhesive spraying module integrated into its side wall and the suspension module begin to work together. The specific mechanism is as follows: Working mechanism of the adhesive spraying module (synchronous spraying): The pump in the power supply box 4 is activated, and the pre-stored quick-drying adhesive is delivered through pipeline to the adhesive spraying tube 26 fixed on the outer wall of the retaining arm 24. The adhesive is sprayed in a mist or fine line form through multiple adhesive nozzles 31 embedded side by side in the retaining arm 24. Since the adhesive spraying direction of the nozzles 31 is all towards the center of the retaining arm 24, the adhesive will evenly cover the area to be patched on the surface of the steering tie rod.

[0033] Working mechanism of the suspension module (elastic pretensioning and release): While the adhesive is being sprayed, the elastic take-up wheel 251 inside the take-up drum 25, under the action of the coil spring, suspends the strain gauge 27 at the center of the circumferential arm 24 through the inelastic pull wire 32. At this time, the pull wire 32 forms a constraint through the binding hole on the side pull plate 271, keeping the strain gauge 27 in a flat position.

[0034] Fitting and Wrapping Action: As the retaining arm 24 continues to close, the automatic patching claw 23 controls the strain gauge 27 to contact and gently press against the adhesive-coated surface of the steering tie rod before the metal arm. The two ends of the strain gauge 27 are always constrained, and under the clamping force of the fully closed retaining arm 24, it automatically and tightly wraps around the steering tie rod.

[0035] Strain Gauge 27: Mechanical Transmission and Measurement Principles Scientific principles and formulas are introduced as follows: After the strain gauge 27 is firmly bonded, the two tie rod force application modules of the bidirectional loader 11 begin to apply alternating tensile and compressive loads to the steering tie rod.

[0036] According to Hooke's law and the resistance strain effect, the measurement mechanism of strain gauge 27 can be described by the following formula: Stress-strain relationship: ; Where $\sigma$ is the axial stress on the cross section of the steering tie rod (unit: Pa), E is the Young's modulus of the steering tie rod material (unit: Pa), and $\varepsilon$ is the micro-strain generated (dimensionless or $\mu\varepsilon$).

[0037] Resistance change of strain gauge 27: When strain gauge 27 deforms with the steering tie rod, the relationship between its resistance change rate $\frac{\Delta R}{R}$ and the strain $\varepsilon$ is as follows: ; Where K is the sensitivity coefficient (constant) of strain gauge 27.

[0038] The data acquisition module converts minute resistance changes into voltage signals using a Wheatstone bridge, and then acquires strain data in real time via analog-to-digital conversion. Since the detection mechanism 2 integrates a wireless transmission module, the data is sent to the host computer without delay.

[0039] Algorithm for generating calibration coefficients: The host computer synchronously receives the strain data $\varepsilon_{measured}$ from strain gauge 27 and the load sensor data $F_{applied}$ inside the bidirectional loader 11.

[0040] The formula for calculating the calibration coefficients $C$ for linear fitting based on the least squares method is as follows: ; By correcting with this coefficient, a high-precision conversion relationship between the force state of the tie rod and the electrical signal can be obtained.

[0041] Automatic stripping stage of strain gauge 27 after testing After the calibration data acquisition is completed, in order to prevent the glue from being difficult to clean or protect the surface of the steering tie rod after it has cured, the system initiates the piece removal procedure, which involves parts including miniature controllable push rod 28, piece removal pull wire 29, and glue cutting wire 272: Action process: The miniature controllable push rods 28 on both sides retract, pulling the plate removal cable 29.

[0042] Cutting Mechanism: The pull wire 29 pulls the rubber cutting wire 272, which was originally loosely attached to the inner wall of the strain gauge 27 at a right angle, and tauts it. Due to the reverse tension provided by the tension rope 274, the rubber cutting wire 272 changes from an "L"-shaped trajectory to a straight cutting trajectory diagonally opposite each other. The localized high shear stress generated by this action instantly severs the adhesive layer between the steering tie rod and the strain gauge 27, causing the strain gauge 27 to detach from the tie rod along with the claw when the circumferential arm 24 opens, avoiding residue.

[0043] The fully automated patching and calibration process significantly improves testing efficiency: Through the linkage design of the automatic patching claw 23, the circumferential arm 24, the glue spraying module and the suspension module, especially the "extend-close claw" single action can simultaneously complete the self-wrapping, self-alignment and self-adhesion of the strain gauge 27, which greatly shortens the preparation time for batch calibration of steering tie rods.

[0044] The spatially staggered distribution design eliminates blind spots in mechanical measurements: the two sets of automatic patching claws 23 within the upper box 21 and lower box 22 are spatially staggered, achieving full circumferential wrapping of the cylindrical steering tie rod. Compared to single-sided patching or structures that only patch vertically, this design can accurately capture the coupling state of bending stress and axial stress of the tie rod under bidirectional tensile and compressive loading, avoiding distortion of strain measurement data caused by eccentric loading, and significantly improving the linearity and confidence of the calibration coefficient $C$.

[0045] The unique cutting wire 272 and strain gauge removal structure enables non-destructive testing and reuse: The linear cutting mechanism, composed of two cutting wires 272 and a miniature controllable push rod 28, utilizes the principle of geometric transformation (from right-angle relaxation to diagonal straight line) to generate high cutting stress within a very small return space. This structure solves the industry pain point of adhesive strain gauges 27 being difficult to remove after calibration, thus damaging the tie rod substrate. After testing, there is no glue residue on the surface of the steering tie rod, and the circumferential arm 24 and automatic patching claw 23 can be immediately used for the calibration of the next tie rod, achieving continuous, clean, and non-destructive operation of the device.

[0046] The embodiments of the present invention have been described above, but the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms based on the guidance of the present embodiments, all of which are within the protection scope of the present embodiments.

Claims

1. A bidirectional loading calibration device for steering tie rods, characterized in that, include: The bidirectional loader (11) has a detection mechanism (2) symmetrically arranged in its two tie rod force application modules. The detection mechanism (2) consists of an upper box (21), a lower box (22) and two sets of automatic patching claws (23). Each set of automatic patching claws (23) contains multiple independent automatic patching claws (23), and the two sets of automatic patching claws (23) are fixed to the inner walls of the upper box (21) and the lower box (22) respectively. The working ends of all automatic patching claws (23) are directed towards the steering rod that passes through the upper box (21) and the lower box (22), and the automatic patching claws (23) in the upper box (21) and the lower box (22) are spatially staggered to achieve full circumferential wrapping. The end of the automatic patching claw (23) is fixedly provided with a circumferential arm (24), and a strain gauge (27) is installed at the center of the circumferential arm (24). The side wall of the circumferential arm (24) is integrated with a suspension module and a glue spraying module. The suspension module adopts an elastic structure and suspends the strain gauge (27) at the center of the circumferential arm (24) through mechanical interlocking. When the automatic patching claw (23) performs the extension-closing action, the suspension module releases the strain gauge (27) and makes it automatically wrap around the steering tie rod. The glue spraying module simultaneously sprays quick-drying glue onto the surface of the steering tie rod to achieve the bonding and fixing of the strain gauge (27). The detection mechanism (2) also integrates a data acquisition module, which communicates with the host computer via wireless transmission, collects strain data of strain gauge (27) and load data of bidirectional loader (11) in real time, and performs linear fitting based on least squares method to generate calibration coefficients.

2. The steering tie rod bidirectional loading calibration device according to claim 1, characterized in that, The lower box (22) is fixed on the detection area end face of the bidirectional loader (11), and the upper box (21) is rotatably set on the lower box (22). The steering rod passes through the center position of the closed upper box (21) and lower box (22), and the steering rod is just between the upper and lower automatic patching claws (23).

3. The steering tie rod bidirectional loading calibration device according to claim 1, characterized in that, The automatic patching claw (23) includes a circling arm (24) fixed at the end of the claw. The closed circling arm (24) is elliptical and has a diameter larger than the steering pull rod. Both the upper and lower sets of automatic patching claws (23) are wrapped around the outside of the steering pull rod from the upper and lower directions.

4. The steering tie rod bidirectional loading calibration device according to claim 3, characterized in that, The upper wall of the upper box (21) is fixedly installed with a power supply box (4), and the power supply box (4) is an integrated device. The power supply box (4) is equipped with a pump body that provides the specified glue to the glue spraying module and pre-stored glue.

5. The steering tie rod bidirectional loading calibration device according to claim 4, characterized in that, The glue spraying module includes a glue spraying tube (26), which is fixed to the outer wall of the arm (24). The glue spraying tube (26) has multiple outlets, each of which has a glue spray nozzle (31). Several glue spray nozzles (31) are embedded side by side in the arm (24). The glue spraying direction of all glue spray nozzles (31) is towards the center of the arm (24), which is used to spray glue when the automatic patching claw (23) moves downward to hug the steering lever.

6. The steering tie rod bidirectional loading calibration device according to claim 5, characterized in that, The suspension module includes a take-up drum (25), which is also fixed to the outer wall of the circumferential arm (24). The inside of the take-up drum (25) is provided with multiple elastic take-up wheels (251), and each elastic take-up wheel (251) is connected to the take-up drum (25) through a coil spring. Each elastic take-up wheel (251) is fixed with a pull wire (32), and a winding force is always applied to the pull wire (32).

7. A bidirectional loading calibration device for steering tie rods according to claim 6, characterized in that, The strain gauge (27) is fixedly provided with side pull plates (271) on both sides near the circumferential arm (24), and the side pull plates (271) are arrayed with binding holes. Each strain gauge wire (32) corresponds to a binding hole and is tied tightly. The strain gauge wire (32) has no elasticity.

8. A bidirectional loading calibration device for steering tie rods according to claim 8, characterized in that, The automatic patching claw (23) first drives the open wrapping arm (24) to move towards the steering tie rod, then controls the wrapping arm (24) to gradually close, and at the same time sprays glue onto the steering tie rod through the glue nozzle (31), then makes the strain gauge (27) press on the steering tie rod first, and finally controls the wrapping arm (24) to completely close, so that the strain gauge (27) is wrapped.

9. A bidirectional loading calibration device for steering tie rods according to claim 7, characterized in that, The detection surface of the strain gauge (27) is provided with two cutting wires (272), and the two cutting wires (272) are closely attached to the inner wall of the strain gauge (27). The two cutting wires (272) run along the edge of the strain gauge (27) at right angles. The right angles of the two cutting wires (272) are obliquely opposite each other. At the same time, a tension rope (274) is fixedly provided at the right angle point of the cutting wire (272). The tension rope (274) is contracted in the tension rope chamber (273), which is opened in the side pull plate (271).

10. A bidirectional loading calibration device for steering tie rods according to claim 9, characterized in that, Both sides of the automatic patching claw (23) are fixedly provided with a miniature controllable push rod (28). The telescopic arm of the miniature controllable push rod (28) is fixedly connected with a patch removal pull line (29). The two patch removal pull lines (29) are respectively connected to one end of the two cutting wires (272). After the test is completed, the cutting wires (272) are pulled by the miniature controllable push rod (28) so that the cutting wires (272) are straightened into a straight line diagonally opposite each other. This process is used to cut the glue tightly against the steering tie rod.

Images