Automobile axle detection platform convenient for comprehensive detection

Abstract

The application relates to the fields of automobile manufacturing and detection technology, and discloses a vehicle axle detection platform facilitating comprehensive detection, a base frame serving as the support base of the detection platform, a vehicle axle fixing frame installed in the middle area of the base frame and used for clamping and positioning a vehicle axle to be detected, a loading transmission mechanism comprising three groups of loading transmission mechanisms with the same structure, and a differential group comprising a first differential and a second differential, wherein the input end of the first differential is connected with the output shaft of a driving motor through a shaft coupling to receive driving power. Through cascade connection of the differential group and self-adaptive load distribution, the application realizes automatic adjustment of power and dynamic balance of load at each loading point under the deformation working condition of the vehicle axle, the pure mechanical structure responds rapidly and does not need complex electronic control; in combination with the spring-hydraulic damping of the worm gear self-locking and the hydraulic double coupler, the loading stability is remarkably improved, the load fluctuation caused by the reaction force is inhibited, and the impact and vibration are effectively absorbed.

Description

Technical Field

[0001] This invention relates to the field of automobile manufacturing and testing, and more specifically, to an automobile axle testing platform that facilitates comprehensive testing. Background Technology

[0002] In the automotive manufacturing and testing field, the axle, as a key component for bearing and transmitting power, directly affects the safety and reliability of the vehicle due to its strength and fatigue performance. Traditional axle testing platforms generally employ a loading method using fixed supports and independent hydraulic cylinders, simulating actual working conditions by applying preset loads to the two half-shaft ends and one input end of the axle.

[0003] However, this detection method has significant technical flaws. When the axle undergoes elastic deformation under load, the displacement of the three loading points differs, causing the actual applied force to deviate from the preset value. Specifically, when a loading point experiences significant displacement due to axle deformation, the corresponding hydraulic cylinder stroke changes, reducing the actual force applied at that point; while other loading points, with smaller deformations, maintain their original applied force. This uneven load distribution means the detection results cannot accurately reflect the axle's stress state under actual working conditions.

[0004] Furthermore, each loading point uses an independently controlled hydraulic system, resulting in slow response and difficulty in achieving coordinated multi-point control. When the load at a certain point needs to be adjusted, the corresponding hydraulic system must be adjusted individually, while the loads at other points remain unchanged, leading to further imbalance in the overall load distribution. Summary of the Invention

[0005] This invention provides a convenient and comprehensive automotive axle testing platform, solving the technical problems in related technologies where fixed loading cannot adapt to the dynamic deformation of the axle, and the slow response speed and difficulty in coordination of the independently controlled hydraulic system at each point leads to uneven load distribution and affects the accuracy of fatigue testing.

[0006] This invention provides a convenient and comprehensive automotive axle testing platform, comprising: The base frame serves as the supporting foundation for the testing platform. The axle mounting bracket is installed in the middle area of ​​the base frame to clamp and position the axle to be tested. The loading transmission mechanism includes three sets of identical loading transmission mechanisms. Each loading transmission mechanism includes a transmission housing, a worm, an internally threaded worm wheel, and a lifting screw. The transmission housing is fixedly installed on the base frame and houses the transmission components inside. The worm is horizontally installed inside the transmission housing, and the internally threaded worm wheel is vertically installed and meshes with the worm. The worm wheel has an internally threaded hole in its center. The lower end of the lifting screw is supported in the transmission housing by a thrust bearing, and the threaded part of the lifting screw passes through the internally threaded hole in the center of the worm wheel and engages with it. The differential assembly includes a first differential and a second differential. The input end of the first differential is connected to the output shaft of the drive motor via a coupling to receive drive power. Of the two output half-shafts of the first differential, one half-shaft is connected to the input end of the second differential via a coupling, and the other half-shaft is connected to the input end of the loading transmission mechanism of the first group via a coupling. The two output half-shafts of the second differential are respectively connected to the input ends of the loading transmission mechanism of the second group and the loading transmission mechanism of the third group via couplings. A hydraulic double coupler is connected to the top of each lifting screw, and a loading head is installed on the top of the hydraulic double coupler; The anti-rotation guide mechanism includes a guide rod and a guide hole. The guide rod is vertically fixed on the base frame, and the guide hole is opened on the flange at the top of the lifting screw. The guide rod and the guide hole are clearance-fitted, allowing the lifting screw to move in the vertical direction while restricting its rotational movement. The loading head is equipped with a clamp for holding the contact point of the axle to be tested, and a pressure sensor is provided between the loading head and the contact point of the axle to be tested.

[0007] Furthermore, when the worm rotates, it drives the worm wheel to rotate. The lifting screw is restricted from rotating by the anti-rotation guide mechanism and can not rotate. The lifting screw achieves vertical lifting motion under the drive of the worm wheel.

[0008] Furthermore, the first differential is equipped with planetary bevel gears, half-shaft bevel gears and planetary gear carriers. The planetary bevel gears are mounted on the planetary gear carriers and mesh with the half-shaft bevel gears on both sides.

[0009] Furthermore, of the two output half-shafts of the first differential, one half-shaft is connected to the input end of the second differential via a coupling, and the other half-shaft is connected to the input end of the loading transmission mechanism of the first group via a coupling.

[0010] Furthermore, the second differential also consists of planetary bevel gears, half-shaft bevel gears, and a planetary gear carrier. Its two output half-shafts are connected to the input ends of the second and third loading transmission mechanisms respectively via couplings.

[0011] Furthermore, the hydraulic dual coupler includes a piston cylinder and a piston rod. The bottom flange of the piston cylinder is fixedly connected to the top flange of the lifting screw by bolts. The piston rod is inserted into the piston cylinder and can move axially along the piston cylinder. The top of the piston rod is rotatably connected to the loading head by a ball joint.

[0012] Furthermore, a compression spring is fitted onto the piston rod. The lower end of the spring is fixed to the piston cylinder via a spring seat, and the upper end is fixed to the piston rod via another spring seat.

[0013] Furthermore, the piston cylinder cavity is filled with hydraulic oil, and an oil port communicating with the cavity is opened on the piston cylinder wall. An adjustable damping valve is installed on the oil port, and the damping valve is connected to the oil tank through an oil pipe.

[0014] Furthermore, the three loading heads correspond to the three stress points of the axle under test, namely the ends of the two half-shafts and one input end.

[0015] Furthermore, the transmission ratio of the worm gear is 40:1, and the worm gear has a self-locking characteristic to prevent the load from being driven in the opposite direction.

[0016] The beneficial effects of this invention are as follows: This invention achieves automatic power adjustment and dynamic load balance at each loading point under axle deformation conditions through the cascading of differential groups and adaptive load distribution. The purely mechanical structure responds quickly and requires no complex electronic control. Combined with the spring-hydraulic damping of the worm gear self-locking and hydraulic dual coupling, it significantly improves loading stability, suppresses load fluctuations caused by reaction forces, and effectively absorbs impacts and vibrations. The ball joint rotating connection between the loading head and the clamp maintains reliable contact under large displacement and angle changes, avoiding stress concentration and local damage. In conjunction with a pressure sensor, it achieves accurate load monitoring.

[0017] Overall, this makes the testing platform more accurately simulate the actual stress state of the vehicle axle, significantly improving the accuracy and repeatability of fatigue testing. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of an automotive axle testing platform that facilitates comprehensive testing according to the present invention; Figure 2 This is a second-view structural diagram of an automotive axle testing platform that facilitates comprehensive testing according to the present invention. Figure 3 This is the invention Figure 1 Side view; Figure 4 This is a third-view structural diagram of an automotive axle testing platform that facilitates comprehensive testing according to the present invention. Figure 5 This is the invention Figure 1 Top view; Figure 6 This is the invention Figure 5 A schematic diagram of the cross-sectional structure of GG.

[0019] In the diagram: 100, base frame; 200, axle to be tested; 300, axle mounting bracket; 400, anti-rotation guide mechanism; 500, differential assembly; 510, planetary bevel gear; 520, half-shaft bevel gear; 530, planetary gear carrier; 600, loading transmission mechanism; 610, lifting screw; 620, transmission housing; 630, worm gear; 640, internal thread worm wheel; 700, drive motor; 800, loading head; 810, pressure sensor; 820, fixture; 900, hydraulic double coupler. Detailed Implementation

[0020] 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.

[0021] like Figures 1-6 As shown, a convenient and comprehensive automotive axle testing platform includes a base frame, an axle mounting bracket, a differential assembly, three sets of loading transmission mechanisms, a hydraulic dual coupler, an anti-rotation guide mechanism, a loading head, a clamp, and a pressure sensor.

[0022] The three loading transmission mechanisms have the same structure. They are designated as the first, second, and third loading transmission mechanisms. Each loading transmission mechanism includes a transmission housing, a worm, an internally threaded worm wheel, and a lifting screw. The transmission housing is fixedly mounted on the base frame and houses the transmission components. The worm is horizontally mounted inside the transmission housing and rotates via bearing support. The internally threaded worm wheel is vertically mounted and meshes with the worm. The worm wheel has an internally threaded hole in its center. The lower end of the lifting screw is supported in the transmission housing by a thrust bearing. The threaded portion of the screw passes through the internally threaded hole in the center of the worm wheel and engages with it. When the worm rotates, it drives the worm wheel to rotate. Since the lifting screw is restricted from rotating by the anti-rotation guide mechanism, it cannot rotate. Therefore, the lifting screw achieves vertical lifting motion under the drive of the worm wheel. The base frame is a rigid frame structure welded from steel profiles, providing a stable support foundation for the entire testing platform. The axle fixing frame is installed in the middle area of ​​the base frame to clamp and position the axle to be tested.

[0023] The differential assembly includes a first differential and a second differential. The input end of the first differential is connected to the output shaft of the drive motor via a coupling to receive drive power. Of the two output half-shafts of the first differential, one half-shaft is connected to the input end of the second differential via a coupling, and the other half-shaft is connected to the input end of the first loading transmission mechanism via a coupling. The two output half-shafts of the second differential are connected to the input ends of the second loading transmission mechanism and the third loading transmission mechanism via couplings, respectively. The differential assembly is a cascaded differential assembly structure, which realizes adaptive power distribution at the three loading points. It should be further explained that the first differential internally contains planetary bevel gears, half-shaft bevel gears, and a planetary gear carrier. The planetary bevel gears are mounted on the planetary gear carrier and mesh with the half-shaft bevel gears on both sides to achieve differential power distribution. Of the two output half-shafts of the first differential, one half-shaft is connected to the input end of the second differential via a coupling, and the other half-shaft is connected to the input end of the first loading transmission mechanism via a coupling. The second differential is also composed of planetary bevel gears, half-shaft bevel gears, and a planetary gear carrier. Its two output half-shafts are connected to the input ends of the second loading transmission mechanism and the third loading transmission mechanism via couplings, respectively. In some embodiments, the transmission ratio of the worm gear is 40:1, which achieves a large transmission ratio while having a self-locking characteristic to prevent the load from driving in the opposite direction.

[0024] A hydraulic double coupler connects the top of each lifting screw to the loading head, providing a flexible connection and buffering function. The hydraulic double coupler includes a piston cylinder and a piston rod. The bottom flange of the piston cylinder is bolted to the top flange of the lifting screw. The piston rod is inserted into the piston cylinder and can move axially along the cylinder. The top of the piston rod is rotatably connected to the loading head via a ball joint, ensuring continued contact and pressure transmission even when the axle deforms. A compression spring is fitted onto the piston rod; the lower end of the spring is fixed to the piston cylinder via a spring seat, and the upper end is fixed to the piston rod via another spring seat.

[0025] Furthermore, the piston cylinder cavity is filled with hydraulic oil, and an oil port communicating with the cavity is opened on the piston cylinder wall. An adjustable damping valve is installed on the oil port, and the damping valve is connected to the oil tank through an oil pipe. When the piston rod is pressed down, the oil in the cavity flows to the oil tank through the damping valve, providing damping buffer; when the pressure decreases, the spring pushes the piston rod to return to its original position, and the oil flows back from the oil tank to the cavity.

[0026] The anti-rotation guiding mechanism includes a guide rod and a guide hole. The guide rod is vertically fixed on the base frame, and the guide hole is opened on the flange at the top of the lifting screw. The guide rod and the guide hole are clearance-fitted, allowing the lifting screw to move in the vertical direction while restricting its rotational movement.

[0027] The three loading heads correspond to the three stress points of the axle, namely the ends of the two half-shafts and one input end. The ball joint rotation connection structure ensures that the contact point between the loading head and the axle can adapt to the angle changes during the deformation of the axle, maintaining effective contact and pressure transmission.

[0028] Furthermore, the loading head is equipped with a clamp for holding the axle contact point to ensure a reliable connection between the loading head and the axle during the loading process.

[0029] Furthermore, a pressure sensor is installed between the loading head and the contact point of the axle to detect pressure and monitor the actual load distribution at each loading point in real time.

[0030] In one embodiment of the present invention, the following supplementary explanation is required: In this embodiment, "differential" specifically refers to a bevel gear type open differential, used to achieve adaptive speed adjustment and torque distribution between the input end and the two output half-shafts. Internally, it consists of planetary bevel gears, half-shaft bevel gears, and a planetary gear carrier. The planetary bevel gears are mounted on the planetary gear carrier and mesh with the half-shaft bevel gears on both sides. It can automatically generate speed differences when the resistance at each loading point is different, ensuring reasonable power distribution.

[0031] The "cascaded differential group" consists of a first differential and a second differential connected in sequence. The first differential divides the input power into two paths, one of which is further divided into two paths by the second differential. This achieves adaptive distribution to the three loading points and has torque-speed complementary characteristics. That is, when the resistance of one path increases and the speed decreases, the speed of the other paths increases accordingly to keep the total load basically constant.

[0032] Worm gear drives are used to achieve high reduction ratio power transmission and self-locking functions. The worm meshes with the worm wheel, causing the worm wheel to rotate. The internal thread at the center of the worm wheel engages with the thread of the lead screw, converting the rotational motion into the axial lifting motion of the lead screw. Under common geometric parameters, worm gear drives have self-locking properties, preventing the axle reaction force from driving the worm in the opposite direction.

[0033] The "lifting screw," as a linear actuator, is used to convert rotational energy into vertical displacement and bear the applied force. Its lower end is supported by a thrust bearing to withstand axial loads and reduce friction, while its upper end is restricted from rotation by an anti-rotation guide mechanism to ensure that the linear lifting is consistent with the loading direction.

[0034] The "anti-rotation guide mechanism" is formed by the clearance fit between the guide rod and the guide hole, which provides guidance and anti-rotation constraint for the lifting screw, reducing the impact of lateral sway and eccentric force on the loading accuracy.

[0035] The "hydraulic dual coupler" is a combined coupling structure of an elastic element and a hydraulic damping element. The piston rod and piston cylinder form controllable damping, and the compression spring provides preload and return force. The damping valve adjusts the damping coefficient by changing the oil flow rate, ensuring smooth operation even under sudden load changes and reducing the interference of impact and vibration on the measurement.

[0036] The damping valve is installed at the oil port that connects to the piston cylinder cavity and is used to adjust the flow resistance of the oil. By changing the valve opening, the damping level during the loading process can be set to match the stiffness and test spectrum of different axles.

[0037] The "ball joint rotation connection" is a universal ball joint structure that allows the loading head to swing at a small angle relative to the piston rod in multiple degrees of freedom to adapt to the attitude changes of the axle contact point and avoid additional bending moment caused by angle mismatch.

[0038] The "clamp" is set on the loading head to reliably hold the force contact point of the axle and form a stable force transmission interface. Depending on the geometry of the axle end being tested, it can be equipped with a V-shaped seat, wedge block or adjustable pressure plate to ensure repeatable positioning and no slippage.

[0039] The pressure sensor is positioned between the loading head and the axle contact point to collect the actual load at each loading point in real time. To prevent lateral forces from affecting the measurement, the sensor is arranged coaxially with the loading direction. The collected signal can be used to record load history or as a reference for closed-loop control.

[0040] A coupling is used to connect the drive source and the differential input to compensate for minor coaxiality and angular deviations, thereby reducing vibration and shock in the transmission system.

[0041] The "drive source" can be a servo motor or a drive motor. Servo motors are suitable for loading conditions that require precise speed / displacement control, while drive motors are suitable for loading requirements with high torque and impact resistance. Both can drive the input end of the first differential through a coupling.

[0042] The "transmission housing" is an enclosed structure that supports components such as worm gears, worm wheels, bearings, and lead screws. It provides installation references and lubrication, dust prevention, and protection functions to ensure the long-term stable operation of the transmission components.

[0043] The "oil tank" and oil pipes form an oil circuit, providing the working medium for the hydraulic dual coupler and enabling oil return and replenishment, while working with the damping valve to complete damping adjustment.

[0044] In one embodiment of the present invention, the following process is specifically included: Step 1: Install the axle to be tested on the axle mounting bracket, adjust the mounting device to make the axle horizontal, and ensure that the two half-shaft ends and the input end of the axle are aligned with the center of the three loading heads respectively; Step 2: Start the drive motor. The drive motor drives the input end of the first differential to rotate through the coupling. The first differential distributes the input rotational power to the two output half shafts. One half shaft drives the first loading transmission mechanism, and the other half shaft drives the second differential. Step 3: After receiving power from the first differential, the worm of the first loading transmission mechanism rotates, driving the internal thread worm wheel to rotate. Since the lifting screw is restricted from rotating by the anti-rotation guide mechanism, it cannot rotate. The rotation of the worm wheel causes the lifting screw to move upward, pushing the hydraulic double coupler and the loading head to apply load to the first force point of the axle. Step 4: After receiving the power from the first differential, the second differential further distributes the power to the second and third loading transmission mechanisms. The working principle of the second and third loading transmission mechanisms is the same as that of the first loading transmission mechanism, which respectively pushes the corresponding loading head to apply load to the second and third force points of the axle. Step 5: When the axle deforms under load, the differential assembly automatically adjusts the force distribution at the three loading points; The specific process is as follows: When the first loading point generates a large reaction force due to the deformation of the axle, the resistance of the first loading transmission mechanism increases, which causes the corresponding output half-shaft speed of the first differential to decrease. According to the characteristics of the differential, the speed of the other output half-shaft increases accordingly, so that the second differential obtains more power, thereby enhancing the force applied by the second and third loading points. In some embodiments, step 5 further includes: the hydraulic dual coupler provides a buffering effect during loading; when the loading head is subjected to a sudden load, the piston rod compresses the spring and pushes the oil through the damping valve to achieve smooth load transfer. Step 6: When the resistance at the second or third loading point changes, the speed between the two output half shafts is adaptively adjusted inside the second differential to maintain the dynamic balance of the load at the second and third loading points. Throughout the testing process, the cascade characteristics of the differential group ensure that the total load at the three loading points remains constant, while the load at each point is automatically adjusted and distributed according to the axle deformation. Step 7: After completing the predetermined loading cycle, reverse the drive motor to make the three loading heads descend synchronously and release the axle load; Remove the inspected axle and prepare for the inspection of the next axle.

[0045] 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 under the guidance of the present invention, all of which are within the protection scope of the present invention.

Claims

1. A convenient and comprehensive automotive axle testing platform, characterized in that, include: The base frame serves as the supporting foundation for the testing platform. The axle mounting bracket is installed in the middle area of ​​the base frame to clamp and position the axle to be tested. The loading transmission mechanism includes three sets of identical loading transmission mechanisms. Each loading transmission mechanism includes a transmission housing, a worm, an internally threaded worm wheel, and a lifting screw. The transmission housing is fixedly installed on the base frame and houses the transmission components inside. The worm is horizontally installed inside the transmission housing, and the internally threaded worm wheel is vertically installed and meshes with the worm. The worm wheel has an internally threaded hole in its center. The lower end of the lifting screw is supported in the transmission housing by a thrust bearing, and the threaded part of the lifting screw passes through the internally threaded hole in the center of the worm wheel and engages with it. The differential assembly includes a first differential and a second differential. The input end of the first differential is connected to the output shaft of the drive motor via a coupling to receive drive power. Of the two output half-shafts of the first differential, one half-shaft is connected to the input end of the second differential via a coupling, and the other half-shaft is connected to the input end of the loading transmission mechanism of the first group via a coupling. The two output half-shafts of the second differential are respectively connected to the input ends of the loading transmission mechanism of the second group and the loading transmission mechanism of the third group via couplings. A hydraulic double coupler is connected to the top of each lifting screw, and a loading head is installed on the top of the hydraulic double coupler; The anti-rotation guide mechanism includes a guide rod and a guide hole. The guide rod is vertically fixed on the base frame, and the guide hole is opened on the flange at the top of the lifting screw. The guide rod and the guide hole are clearance-fitted, allowing the lifting screw to move in the vertical direction while restricting its rotational movement. The loading head is equipped with a clamp for holding the contact point of the axle to be tested, and a pressure sensor is provided between the loading head and the contact point of the axle to be tested.

2. The convenient and comprehensive automotive axle testing platform according to claim 1, characterized in that, When the worm rotates, it drives the worm wheel to rotate. The lifting screw is restricted from rotating by the anti-rotation guide mechanism and can not rotate. The lifting screw achieves vertical lifting motion under the drive of the worm wheel.

3. The convenient and comprehensive automotive axle testing platform according to claim 1, characterized in that, The first differential contains a planetary bevel gear, a half-shaft bevel gear, and a planetary gear carrier. The planetary bevel gear is mounted on the planetary gear carrier and meshes with the half-shaft bevel gears on both sides.

4. The convenient and comprehensive automotive axle testing platform according to claim 3, characterized in that, Of the two output half-shafts of the first differential, one half-shaft is connected to the input end of the second differential via a coupling, and the other half-shaft is connected to the input end of the loading transmission mechanism of the first group via a coupling.

5. The convenient and comprehensive automotive axle testing platform according to claim 4, characterized in that, The second differential also consists of planetary bevel gears, half-shaft bevel gears, and a planetary gear carrier. Its two output half-shafts are connected to the input ends of the second and third load transmission mechanisms respectively via couplings.

6. The convenient and comprehensive automotive axle testing platform according to claim 1, characterized in that, The hydraulic dual coupling includes a piston cylinder and a piston rod. The bottom flange of the piston cylinder is fixedly connected to the top flange of the lifting screw by bolts. The piston rod is inserted into the piston cylinder and can move axially along the piston cylinder. The top of the piston rod is rotatably connected to the loading head through a ball joint.

7. The convenient and comprehensive automotive axle testing platform according to claim 6, characterized in that, A compression spring is fitted onto the piston rod. The lower end of the spring is fixed to the piston cylinder by a spring seat, and the upper end is fixed to the piston rod by another spring seat.

8. The convenient and comprehensive automotive axle testing platform according to claim 7, characterized in that, The piston cylinder is filled with hydraulic oil. The piston cylinder wall has an oil port that communicates with the cavity. An adjustable damping valve is installed on the oil port and is connected to the oil tank through an oil pipe.

9. The convenient and comprehensive automotive axle testing platform according to claim 1, characterized in that, The three loading heads correspond to the three stress points of the axle to be tested, which are the ends of the two half-shafts and one input end.

10. The convenient and comprehensive automotive axle testing platform according to claim 1, characterized in that, The transmission ratio of the worm gear is 40:

1. The worm gear has a self-locking characteristic to prevent the load from being driven in the opposite direction.

Images