Limit differential working condition test bench for inter-axle differential of drive axle assembly

Abstract

The utility model belongs to the technical field of vehicles, provides a test bench for ultimate differential working conditions of an inter-axle differential of a drive axle assembly, and aims to simulate the condition that the adhesive force of a rear axle is larger and the adhesive force of a middle axle is smaller in a duplex-axle vehicle type of a commercial vehicle, test the strength of each part of the inter-axle differential, and improve the working efficiency of the inter-axle differential. Comprising an intermediate axle assembly, a supporting and pressing device arranged below a plate spring seat of the intermediate axle assembly, an input end dynamometer connected with an input end of the intermediate axle assembly, and a first output end dynamometer and a second output end dynamometer which are in transmission connection with output ends of wheel edges on two sides of the intermediate axle assembly respectively, the through shaft locking mechanism is fixedly connected with the output end of a through shaft of the intermediate axle assembly, the temperature sensor and the vibration sensor are arranged on the intermediate axle assembly, the rotating speed of the through shaft is zero through the through locking mechanism, the limit differential working condition is simulated, and the state of the intermediate axle assembly is monitored through the monitoring device. And data analysis of test results is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicles, and particularly relates to a test bench for the ultimate differential condition of the inter-axle differential of a drive axle assembly. Background Art

[0002] In commercial vehicle double-link axle models, power is first transmitted to the middle axle through the drive shaft. The inter-axle differential receives and distributes it to the middle axle and the rear axle. The middle axle and the rear axle are connected by a drive shaft. The inter-axle differential allows the middle axle and the rear axle to rotate at different speeds. On the one hand, it allows the speed difference between the middle and rear axles during turning. On the other hand, it can meet the driving requirements of the vehicle on uneven roads. The inter-axle differential is located above the middle axle, and the assembly position is above the oil level of the lubricating oil. The lubrication method is splash lubrication, and the working environment is relatively harsh. When the lubrication of the inter-axle differential is insufficient, if the adhesion of the rear axle is large while the adhesion of the middle axle is small, at this time, the speed of the through shaft is zero, and most of the power is transmitted to the middle axle, and the speed of the middle axle increases sharply. At this time, the ultimate differential occurs, and the related components of the differential are extremely easy to fail. Common failure situations include the deformation of the thrust washer, the wear of the cross shaft, the wear of the planetary gear, the sintering of the planetary gear and the cross shaft, etc. Especially when driven by an electric motor in the form of central drive, the speed of the electric motor increases faster than that of the engine, which puts higher requirements on the strength of the inter-axle differential. At present, there is no test method stipulated by national standards and industry standards for the inter-axle differential of commercial vehicle drive axles. Therefore, a test method is needed to simulate the situation where the adhesion of the rear axle of a commercial vehicle double-link axle model is large while the adhesion of the middle axle is small, and test the strength of the inter-axle differential.

[0003] At present, four dynamometers are used for the test of the inter-axle differential of the commercial vehicle middle axle assembly. To simulate the situation where the adhesion of the rear axle of a commercial vehicle double-link axle model is large while the adhesion of the middle axle is small, it is necessary to make the speed of the output end of the through shaft zero and the speed of the middle axle increase. At this time, the ultimate differential occurs, but the dynamometer connected to the output end of the through shaft cannot control the speed to be zero for a long time, which is easy to damage the equipment. Summary of the Utility Model

[0004] The purpose of the utility model is to propose a test bench and a test method for the ultimate differential condition of the inter-axle differential of a commercial vehicle drive axle assembly only using three dynamometers in view of the situation that there is no test method stipulated by national standards and industry standards for the inter-axle differential of commercial vehicle drive axles at present. It can simulate the situation where the adhesion of the rear axle of a commercial vehicle double-link axle model is large while the adhesion of the middle axle is small, and test the strength of the inter-axle differential.

[0005] In order to achieve the above purpose, the utility model provides a test bench for the ultimate differential condition of the inter-axle differential of a drive axle assembly, and the technical scheme adopted is as follows:

[0006] A test bench for the ultimate differential working condition of the inter-axle differential of a drive axle assembly, characterized by comprising:

[0007] The intermediate axle assembly;

[0008] A support and pressing mechanism, arranged under the leaf spring seat of the intermediate axle assembly, for supporting and fixing the intermediate axle assembly;

[0009] An input end dynamometer, with its output end drivingly connected to the input end of the intermediate axle assembly;

[0010] An output end dynamometer, including a first output end dynamometer and a second output end dynamometer, which are respectively drivingly connected to the wheel side output ends on both sides of the intermediate axle assembly;

[0011] A through shaft locking mechanism, fixedly connected to the through shaft output end of the intermediate axle assembly;

[0012] A monitoring device, including a temperature sensor and a vibration sensor arranged on the intermediate axle assembly.

[0013] Further, the support and pressing mechanism includes a base, a support plate, a pressing plate and adjusting bolts. The support plate is fixedly connected above the base. The support plate and the pressing plate are respectively located above and below the intermediate axle assembly, and are fixedly connected to each other through the adjusting bolts.

[0014] Further, an adjusting groove is arranged on the upper end surface of the support plate. The length of the adjusting groove is distributed along the axial direction of the through shaft and is slidably connected with the head of the adjusting bolt in a matching manner. A first adjusting hole is arranged on the pressing plate, which is distributed corresponding to the position of the adjusting groove and is slidably connected with the threaded end of the adjusting bolt in a matching manner. The threaded end of the adjusting bolt is fixedly connected to the pressing plate through a fastening nut.

[0015] Further, the through shaft locking mechanism is composed of a locking bracket and a connecting plate that slides up and down above the locking bracket. A fixed flange is arranged on the connecting plate for fixing the transmission shaft connected to the through shaft.

[0016] Further, a second adjusting hole with a length distributed along the vertical direction is arranged on the locking bracket. A bolt hole is arranged on the connecting plate, which is distributed corresponding to the position of the second adjusting hole. The fixing bolt passes through the bolt hole and the second adjusting hole and is fastened through a nut.

[0017] Further, both the wheel side output ends on both sides of the intermediate axle assembly are connected to the first output end dynamometer and the second output end dynamometer through transmission shafts and wheel side connection devices. The wheel side connection device includes a wheel side connection cylinder, a hub connection disc and a transmission shaft connection disc fixedly connected to both axial ends of the wheel side connection cylinder. The hub connection disc is fixedly connected to the wheel side output end of the intermediate axle assembly. The transmission shaft connection disc is fixedly connected to the transmission shaft. The transmission shaft is connected to the first output end dynamometer or the second output end dynamometer.

[0018] Furthermore, the monitoring device further includes a torque sensor, and the torque sensor is disposed on the transmission shaft connected between the through shaft locking mechanism and the through shaft of the middle bridge assembly.

[0019] Furthermore, it further includes a transparent oil pipe with scales on its surface, and the transparent oil pipe is connected to the oil drain hole on the middle bridge assembly.

[0020] The beneficial effects of the present utility model are as follows:

[0021] 1. By providing a through locking mechanism, the rotation speed of the through shaft of the middle bridge assembly is zero to simulate the extreme differential working condition, and the height of the through locking mechanism is adjustable, which can be applied to middle bridge assemblies of different product specifications and models, ensuring that the through shaft avoids bearing bending moments;

[0022] 2. The middle bridge assembly is fixedly pressed by the supporting and pressing mechanism to ensure the stability of the test piece during the test, and the adjusting grooves and the first adjusting holes are arranged on the supporting plate and the pressing plate in a corresponding distribution, which can be adjusted according to middle bridge assemblies of different specifications and models;

[0023] 3. On both sides of the wheel side output end of the middle bridge assembly, a wheel side connecting device is provided as a connecting piece, and the hub connecting disc, the transmission shaft connecting disc and the wheel side connecting cylinder in the wheel side connecting device are all detachably connected. By replacing different connecting discs, the connection of middle bridge assemblies of different specifications can be satisfied, effectively reducing the test cost;

[0024] 4. By providing a monitoring device, the temperature, vibration value and through shaft torque of the middle bridge assembly are monitored in real time, which is convenient for subsequent data analysis of the test results. Description of the Drawings

[0025] Figure 1 It is a schematic structural diagram of the present utility model

[0026] Figure 2 It is a schematic connection structure diagram of the supporting and pressing mechanism and the middle bridge assembly

[0027] Figure 3 It is a schematic structural diagram of the supporting plate

[0028] Figure 4 It is a schematic structural diagram of the pressing plate

[0029] Figure 5 It is a schematic diagram of the through shaft locking mechanism

[0030] Figure 6 It is a schematic structural diagram of the wheel side connecting device

[0031] Among them, 1 - intermediate axle assembly, 2 - first output end dynamometer, 3 - first transmission shaft, 4 - second output end dynamometer, 5 - second transmission shaft, 6 - wheel side connection device, 7 - support pressing mechanism, 8 - input end dynamometer, 9 - third transmission shaft, 10 - through shaft locking mechanism, 11 - fourth transmission shaft, 12 - temperature sensor, 13 - vibration sensor, 14 - torque sensor, 15 - transparent oil pipe, 16 - base, 17 - support plate, 18 - pressing plate, 19 - adjusting bolt, 20 - fastening nut, 21 - adjusting groove, 22 - first adjusting hole, 23 - locking bracket, 24 - connecting plate, 25 - fixed flange, 26 - second adjusting hole, 27 - bolt hole, 28 - wheel side connection cylinder, 29 - hub connection disk, 30 - transmission shaft connection disk. Detailed implementation manners

[0032] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0033] In the description of the utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the view direction or positional relationship, and is only for the convenience of describing the utility model, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the utility model.

[0034] As Figures 1-6 shown, a test bench for the ultimate differential speed condition test of the inter-axle differential of a drive axle assembly includes an intermediate axle assembly 1, a first output end dynamometer 2 and a second output end dynamometer 4 respectively connected to the two wheel side output ends of the intermediate axle assembly 1, an input end dynamometer 8 connected to the input end of the intermediate axle assembly 1, a through shaft locking mechanism 10 connected to the through shaft output end of the intermediate axle assembly 1, and two groups of support pressing mechanisms 7 respectively arranged below the leaf spring seats of the intermediate axle assembly 1.

[0035] Specifically, the first output end dynamometer 2 is respectively connected to the wheel side output ends on both sides of the intermediate axle assembly 1 through the first transmission shaft 3 and the wheel side connection device 6, and the input end dynamometer 8 is connected to the input end of the intermediate axle assembly 1 through the third transmission shaft 9.

[0036] The wheel side connection device 6 is as Figure 1 and Figure 6As shown, it is composed of a wheel-end connecting cylinder 28, a hub connecting disc 29, and a transmission shaft connecting disc 30. The hub connecting disc 29 and the transmission shaft connecting disc 30 are respectively coaxially fixed at the axial two ends of the wheel-end connecting cylinder 28. Mounting holes are provided at corresponding positions on the axial two ends of the wheel-end connecting cylinder 28, the hub connecting disc 29, and the transmission shaft connecting disc 30. The hub connecting disc 29 and the transmission shaft connecting disc 30 are detachably fixed to the wheel-end connecting cylinder 28 by bolts. By replacing different connecting discs, the connection of different mid-bridge assemblies 1 can be satisfied, saving costs. The hub connecting disc 29 is fixedly connected to the wheel-end output end of the mid-bridge assembly 1, and the transmission shaft connecting disc 30 is connected to the first transmission shaft 3 or the second transmission shaft 5. The first transmission shaft 3 and the second transmission shaft 5 are respectively connected to the first output-end dynamometer 1 and the second output-end dynamometer 4 to complete the transmission.

[0037] As Figure 1 , Figure 2 , Figure 3 and Figure 4 shown, there are two sets of support pressing mechanisms 7, which are respectively located below the leaf spring seats on both sides of the mid-bridge assembly 1, and are composed of a base 16, a support plate 17, a pressing plate 18, an adjusting bolt 19, and a fastening nut 20; the support plate 17 is fixedly connected above the base 16 by bolts, and the support plate 17 is located below the mid-bridge assembly 1. An adjusting groove 21 is provided on the upper end surface of the support plate 17 and is distributed along the axis direction of the through shaft. The cross-section of the adjusting groove 21 is a convex structure; the pressing plate 18 is located above the mid-bridge assembly 1. A first adjusting hole 22 is provided on the upper end surface of the pressing plate 18. The length of the first adjusting hole 22 is distributed along the axis direction of the through shaft, and the position corresponds to the adjusting groove 21; the head of the adjusting bolt 19 is located in the adjusting groove 21 and can slide along the length direction of the adjusting groove 21, and its threaded end passes upward through the first adjusting hole 22, and the threaded end can slide along the length direction of the first adjusting hole 22. Through the settings of the adjusting groove 21 and the first adjusting hole 22, the position of the adjusting bolt 19 can be adjusted, so as to be suitable for the fixing of different specifications of the mid-bridge assembly 1. After the position adjustment is completed, the mid-bridge assembly 1 is fixed to the support pressing mechanism 7 by tightening the fastening nut 20 on the threaded end of the adjusting bolt 19.

[0038] As Figure 1 and Figure 5As shown in the figure, the through-shaft locking mechanism 10 is composed of a locking bracket 23, a connecting plate 24 and a fixed flange 25. The locking bracket 23 is provided with second adjustment holes 26 distributed along the height direction. The connecting plate 24 is provided with bolt holes 27 corresponding to the positions of the second adjustment holes 26. The connecting plate 24 can slide up and down along the locking bracket 23 to adjust the height. After the adjustment is completed, the bolt passes through the bolt hole 27 and the second adjustment hole 26 and is fixed by a nut, so as to fix the connecting plate 24 and the locking bracket 23. The fixed flange 25 is fixedly connected to one side surface of the connecting plate 24 close to the middle bridge assembly 1. The output end of the through-shaft of the middle bridge assembly 1 is connected with a fourth transmission shaft 11, and the fourth transmission shaft 11 is fixedly connected to the fixed flange 25. The through-shaft can be fixed by the through-shaft locking mechanism 10 to make the rotational speed of the through-shaft zero, so as to simulate the working condition of a commercial vehicle double-link bridge model with a larger adhesion force on the rear axle and a smaller adhesion force on the middle bridge. Moreover, the height of the through-shaft locking mechanism 10 is adjustable, which can avoid the through-shaft from bearing bending moment.

[0039] The device is also provided with a monitoring device. The monitoring device includes a temperature sensor 12, a vibration sensor 13 and a torque sensor 14. The temperature sensor 12 is a patch-type thermocouple and is arranged on the outer surface of the middle bridge assembly 1, and is used to monitor the real-time temperature of the middle bridge assembly 1 during the test and form a temperature curve, so as to conduct a comparative analysis on the temperature change trend and the temperature at the time of failure in different working condition experiments; the vibration sensor 13 is arranged on the outer surface of the middle bridge assembly 1 and is used to monitor the vibration value, so as to conduct a weak part analysis by combining the change of the vibration value and the failure part; the torque sensor 14 is a strain gauge and is arranged on the fourth transmission shaft 11. The torque sensor 14 can be used to monitor the torque magnitude at the through-shaft.

[0040] In addition, a transparent oil pipe 15 is also connected to the oil drain hole at the bottom of the middle bridge assembly 1. The transparent oil pipe 15 is provided with scale lines, and the oil level in the bridge is monitored through the transparent oil pipe 15.

[0041] When conducting tests using this device, first install the middle bridge assembly 1, perform preloading according to requirements, and control the rotational speed or torque of the input dynamometer and the output dynamometer respectively. Different dynamic conditions of the entire bridge can be preloaded to simulate different lubrication conditions in actual vehicles. After unloading, the output end of the through shaft is connected to the through shaft locking mechanism 10 through the fourth transmission shaft 11. Then enter the formal test, and control the torque or rotational speed through the input dynamometer 8, the first output dynamometer 2, and the second output dynamometer 4 respectively. At this time, connect the through shaft to the through shaft locking mechanism 10, and the rotational speed is zero. The through shaft and the input shaft are in the extreme differential speed condition. When there is a component failure in the inter-axle differential of the middle bridge assembly, the operation of each test end stops. During the test, monitor and record the temperature of the sample to be tested through the temperature sensor 12, monitor and record the vibration of the middle bridge assembly 1 through the vibration sensor 13, monitor and record the torque received by the through shaft through the torque sensor 14 connected to the strain analyzer, and monitor and record the oil level change through the transparent oil pipe 15. After the test, draw a temperature curve based on the temperature data collected by the temperature sensor 12, and conduct a comparative analysis of the temperature change trend and the temperature at the time of failure in different working condition tests. Analyze the change in vibration value during the test through the vibration data collected by the vibration sensor 13, analyze the torque change at the through shaft through the strain data collected by the torque sensor 14 connected to the strain analyzer. Combining the above data, the oil level change, and the failure location and failure conditions recorded after the sample is disassembled and inspected, find the weak parts and provide improvement ideas for the designer.

[0042] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements can still be made, and these improvements should also be regarded as the protection scope of the present invention.

Claims

1. A test bench for the limit differential working condition of the inter-axle differential of a drive axle assembly, characterized in that: include: Middle bridge assembly; A support and clamping mechanism is arranged below the leaf spring seat of the middle bridge assembly and is used to support and fix the middle bridge assembly; The input end is a dynamometer, and the output end is transmission-connected to the input end of the intermediate axle assembly; The output end dynamometers include a first output end dynamometer and a second output end dynamometer, which are respectively connected to the wheel side output ends on both sides of the middle axle assembly; A through shaft locking mechanism, fixedly connected to the through shaft output end of the middle axle assembly; The monitoring device includes a temperature sensor and a vibration sensor arranged on the center bridge assembly.

2. The drive axle assembly inter-axle differential limit differential operating condition test bench according to claim 1, characterized in that: The supporting and clamping mechanism includes a base, a support plate, a pressure plate and an adjusting bolt. The support plate is fixedly connected to the top of the base. The support plate and the pressure plate are respectively located above and below the middle bridge assembly and are fixedly connected by adjusting bolts.

3. The drive axle assembly inter-axle differential limit differential operating condition test bench according to claim 2, characterized in that: An adjustment groove is provided on the upper end surface of the support plate, the length of which is distributed axially along the through-axis and is slidably connected to the head of the adjusting bolt. A first adjustment hole is provided on the pressure plate, which is distributed corresponding to the position of the adjustment groove and is slidably connected to the threaded end of the adjusting bolt. The threaded end of the adjusting bolt is fastened to the pressure plate through a fastening nut.

4. The drive axle assembly inter-axle differential limit differential operating condition test bench according to claim 1, characterized in that: The through shaft locking mechanism is composed of a locking bracket and a connecting plate slidably connected to the top of the locking bracket. A fixing flange is provided on the connecting plate for fixing the transmission shaft connected to the through shaft.

5. The drive axle assembly inter-axle differential limit differential operating condition test bench according to claim 4, characterized in that: The locking bracket is provided with a second adjustment hole whose length is distributed in the vertical direction, and the connecting plate is provided with bolt holes distributed corresponding to the positions of the second adjustment holes. The fixing bolt passes through the bolt hole and the second adjustment hole and is fastened by a nut.

6. The drive axle assembly inter-axle differential limit differential operating condition test bench according to claim 1, characterized in that: The wheel side output ends on both sides of the mid-bridge assembly are connected to the first output end dynamometer and the second output end dynamometer through a transmission shaft and a wheel side connecting device, the wheel side connecting device includes a wheel side connecting cylinder, a hub connecting plate fixedly connected to the axial ends of the wheel side connecting cylinder, and a transmission shaft connecting plate, the wheel hub connecting plate is fixedly connected to the wheel side output end of the mid-bridge assembly, the transmission shaft connecting plate is fixedly connected to the transmission shaft, and the transmission shaft is connected to the first output end dynamometer or the second output end dynamometer.

7. The drive axle assembly inter-axle differential limit differential operating condition test bench according to claim 1, characterized in that: The monitoring device also includes a torque sensor, which is arranged on a transmission shaft connected between the through-shaft locking mechanism and the through-shaft of the middle axle assembly.

8. The drive axle assembly inter-axle differential limit differential operating condition test bench according to claim 1, characterized in that: It also includes a transparent oil pipe with scales on the surface, and the transparent oil pipe is connected to the oil drain hole on the middle bridge assembly.

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