Hydraulic drive axle testing device

Abstract

The utility model relates to a hydraulic drive axle testing device which comprises a hydraulic axle, a power transmission mechanism and an uphill and downhill simulation mechanism. The power transmission mechanism is used for providing driving force for the hydraulic bridge to enable the hub to rotate. The uphill and downhill simulation mechanism comprises a plurality of movable balancing weights and a connecting mechanism, the movable balancing weights are rotationally connected to the hub through the connecting mechanism, and the rotating central axis of each movable balancing weight is parallel to the rotating central axis of the hub. According to the invention, the inertia effect and the centrifugal force change of the movable balancing weight are utilized to form a periodic additional load in the rotation process of the hub, so that the uphill and downhill working conditions are simulated. The movable balancing weight can freely swing around the axis of the movable balancing weight to dynamically change the load of the drive axle, so that the test device can simulate the running states of vehicles with different gradients. In addition, the device can further comprise a static balancing weight used for providing additional mass adjustment and optimizing inertia characteristics.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of hydraulic drive axle testing device. BACKGROUND

[0002] In the research and development process of vehicle and mechanical equipment, the performance test of drive axle is the key link to ensure its reliability and durability. The traditional test method is usually to install the drive axle on the lawn mower or other actual carrier, and carry out long-term durability test. However, this method has many limitations, the test cycle is long, and since the working time of the lawn mower or other vehicles is limited, it usually takes several months to complete a complete test, resulting in low test efficiency, which is not conducive to product rapid iteration and optimization. The environment is uncontrollable, and under real working conditions, the test results may fluctuate greatly due to factors such as terrain, climate and load, making it difficult to ensure the stability and repeatability of the data. It is difficult to accurately simulate extreme working conditions, and it is difficult to accurately simulate steep slopes, heavy loads and high-intensity continuous working environment in actual driving test, resulting in limited test conditions and inability to fully evaluate the performance of the drive axle in special situations. UTILITY MODEL CONTENTS

[0003] The utility model aims at solving the above prior art deficiencies, and provides a kind of hydraulic drive axle testing device.

[0004] A kind of hydraulic drive axle testing device, hydraulic bridge, uphill and downhill simulation mechanism, power transmission mechanism, the power transmission mechanism is used to transmit power to hydraulic bridge, wheel hub is provided on the hydraulic bridge, the wheel hub is rotated by the hydraulic bridge, the uphill and downhill simulation mechanism includes a plurality of movable counterweight, connecting mechanism, the movable counterweight is rotatably connected on the wheel hub by connecting mechanism, the axis of rotation center of movable counterweight is parallel with the axis of rotation center of wheel hub.

[0005] Further, the connecting mechanism includes screw rod, nut, spacer sleeve, the wheel hub surface is provided with a plurality of installation sites along the circumference, the installation site and the counterweight surface are provided with through holes, the screw rod is arranged in the installation site and the counterweight through hole, the spacer sleeve is located between the inner side of counterweight and the outer side of screw rod, and the nut is used for locking.

[0006] Further, the movable counterweight is arranged along the circumference of the wheel hub, and the mass distribution of the counterweight relative to the wheel hub is asymmetrically arranged.

[0007] Further, a plurality of stationary counterweights are further provided on the wheel hub, and the stationary counterweights are fixedly connected with the wheel hub.

[0008] Further, the stationary counterweight is provided with a through hole in the center, and the stationary counterweight is fixedly connected with the wheel hub by bolts.

[0009] Further, the movable counterweight and the stationary counterweight are installed on both sides of the wheel hub

[0010] Advantages: Compared with the prior art, the utility model has the following advantages:

[0011] By installing the movable counterweight and the static counterweight on the wheel hub, the load change under different slope angles can be accurately simulated, without real slope, greatly reducing the space requirement and construction cost of the test equipment.

[0012] Since the movable counterweight can freely swing around its own axis, its inertia force and centrifugal force can dynamically change with the rotation of the wheel hub, thereby truly reproducing the stress state of the drive axle on the ramp.

[0013] The static counterweight is used to adjust the overall mass distribution of the wheel hub, ensuring more stable test conditions.

[0014] Traditional tests take months to complete, while the test device of the present application can operate continuously for 24 hours a day, significantly improving test efficiency and accelerating product development process.

[0015] The adjustable connecting mechanism (screw + nut + spacer) allows the arrangement of the counterweight to be adjusted uniformly or non-uniformly, suitable for test scenarios with different load distribution requirements.

[0016] By arranging different mass counterweights asymmetrically around the wheel hub, the running state of the vehicle on complex terrain with uneven slopes can be simulated, and the stability and adaptability of the hydraulic axle can be tested.

[0017] Combining the swing inertia principle, torque calculation and dynamic mass distribution model ensures high accuracy of test data, and the performance of the drive axle under different slope and load conditions is scientifically verified.

[0018] With modular design, the installation method of the movable counterweight and the static counterweight is easy to replace and adjust, making the test equipment more durable and the maintenance cost lower. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a schematic diagram of a hydraulic drive axle test device;

[0020] Figure 2 is a schematic diagram of an uphill and downhill simulation mechanism;

[0021] Figure 3 is a front view of the uphill and downhill simulation mechanism;

[0022] Figure 4 is a side view of the uphill and downhill simulation mechanism;

[0023] In the figure, 1 is an uphill and downhill simulation mechanism, 2 is a movable counterweight, 3 is a static counterweight, and 4 is a wheel hub. DETAILED DESCRIPTION

[0024] In order to deepen the understanding of the utility model, the utility model will be further described in combination with embodiments and drawings below, and the embodiments are only used to explain the utility model and do not constitute the limitation to the protection scope of the utility model.

[0025] A kind of hydraulic drive axle testing device, including hydraulic axle, uphill and downhill simulation mechanism 1, power transmission mechanism.Power transmission mechanism is used to transmit power to hydraulic axle, and wheel hub 4 is arranged on the hydraulic axle, and wheel hub 4 is rotated by the hydraulic axle.Besides, uphill and downhill simulation mechanism 1 includes multiple movable counterweight 2 and connecting mechanism, movable counterweight 2 is rotatably connected on wheel hub 4 by connecting mechanism, and the axis of rotation center of movable counterweight 2 is parallel to the axis of rotation center of wheel hub 4.

[0026] The core principle of the testing device is to simulate the operating state of hydraulic drive axle under different slope conditions.Power transmission mechanism provides driving force to hydraulic axle, so that wheel hub 4 rotates.Movable counterweight 2 is connected with wheel hub 4 by connecting mechanism, and freely swings around its axis when wheel hub 4 rotates, thereby simulating the stress state of vehicle on different slopes.Because the distribution of counterweight affects the inertia characteristics of wheel hub 4, the performance of hydraulic drive axle under different working conditions can be effectively tested.

[0027] In a possible implementation, the connecting mechanism includes screw rod, nut and spacer sleeve.Wheel hub 4 surface is provided with multiple mounting sites along the circumference, and mounting site and counterweight surface are provided with through hole, screw rod is arranged in mounting site and counterweight through hole, spacer sleeve is located between the inner side of counterweight and the outer side of screw rod, and nut is used for locking.

[0028] The connecting mechanism realizes stable installation of movable counterweight 2 by the cooperation of screw rod and nut, and ensures that counterweight can freely rotate around screw rod by using spacer sleeve.The distribution of mounting site enables multiple counterweights to be installed uniformly or non-uniformly, so as to adjust the inertia characteristics of testing device.

[0029] In a possible implementation, movable counterweight 2 is arranged along the circumference of wheel hub 4, and the mass distribution of counterweight relative to wheel hub 4 is asymmetrically arranged.

[0030] The design arranges counterweights of different masses along the circumference of wheel hub 4, so that wheel hub 4 forms asymmetric inertia characteristics in the process of rotation, to simulate the operating state of vehicle on uneven slope.This asymmetric arrangement can more accurately test the adaptability of hydraulic axle under complex terrain.

[0031] In a possible implementation, multiple stationary counterweights 3 are further arranged on wheel hub 4, and stationary counterweight 3 is fixedly connected with wheel hub 4.

[0032] The static counterweight 3 is used to provide additional mass adjustment and is fixed on the surface of the wheel hub 4 to change the inertia characteristics of the wheel hub 4. During the test, the static counterweight 3 does not rotate with the wheel hub 4 and does not move relatively, which plays a role in stabilizing inertia.

[0033] In one possible implementation, the static counterweight 3 is provided with a through hole, and the static counterweight 3 is fixedly connected with the wheel hub 4 through bolts.

[0034] This design connects the static counterweight 3 through bolts, so that it can be firmly fixed on the surface of the wheel hub 4. The through hole is provided to flexibly adjust the position of the counterweight to optimize the mass distribution.

[0035] In one possible implementation, the movable counterweight 2 and the static counterweight 3 are installed on both sides of the wheel hub 4.

[0036] This design arranges the movable counterweight 2 and the static counterweight 3 on both sides of the wheel hub 4 respectively to adjust the overall mass distribution, so that the test device can more accurately simulate the stress condition of the hydraulic bridge under different slope conditions.

[0037] Working principle: In the drive axle experiment, the traditional slope test needs an actual slope or applies resistance through a loading system to simulate uphill and downhill working conditions. However, this method has high construction cost and is difficult to adjust. Therefore, a freely swingable counterweight can be installed on the outside of the wheel hub 4, which dynamically changes the load during the rotation of the wheel hub 4 by using the inertia effect and centrifugal force change of the counterweight, thereby simulating uphill and downhill working conditions.

[0038] During real uphill and downhill processes, the drive axle of the vehicle will be subjected to the change of the gravity component force caused by the slope, that is:

[0039] When going uphill, the gravity component force increases the load of the drive axle, and the drive system needs a larger torque to maintain forward movement.

[0040] When going downhill, the gravity component force reduces the load of the drive axle, and even generates a forward thrust, making the vehicle more easily slide.

[0041] When the drive axle is directly operated on flat ground, the dynamic load caused by the slope does not exist, so a method is needed to dynamically change the load of the drive axle to simulate the slope working condition.

[0042] Assume:

[0043] m is the mass of the counterweight, r is the suspension radius of the swing counterweight, θ(t) is the swing angle of the counterweight relative to the wheel hub 4, I is the moment of inertia of the wheel hub 4, and ω is the angular velocity of the wheel hub 4.

[0044] When the wheel hub 4 rotates, the inertia force F of the counterweight changes with the angular velocity and the swing angle:

[0045] F = mrω2cos(θ(t)) ;

[0046] This force will affect the rotational dynamics of the wheel hub 4, so that the drive axle experiences a periodic load variation, similar to the change in driving force demand when driving uphill and downhill.

[0047] When the wheel hub 4 starts to accelerate, the swing weight will lag slightly due to inertia, causing it to swing backward relative to the wheel hub 4. This is equivalent to increasing the rotational inertia of the wheel hub 4 at a certain moment, so that the drive axle experiences a greater load, similar to the resistance encountered when driving uphill.

[0048] When the wheel hub 4 speed increases, the weight block will be thrown outward due to centrifugal force, which will cause an instantaneous increase in load.

[0049] When the wheel hub 4 suddenly decelerates (i.e. angular velocity ω drops), the weight block will continue to move in the original direction due to inertia. At this time:

[0050] The rotational speed of the wheel hub 4 drops, and the inertia of the weight block causes it to swing forward relative to the wheel hub 4.

[0051] This is similar to the situation when the vehicle suddenly releases the accelerator while driving downhill, and the load on the powertrain decreases, while gravity propels the vehicle forward.

[0052] Physical explanation: F = ma; where the angular acceleration α of the wheel hub 4 suddenly becomes smaller, causing the weight block to swing forward relative to the wheel hub 4 due to inertia.

[0053] Uphill simulation: When the weight block swings backward, it increases the rotational load of the drive axle, so that the drive system needs additional torque to overcome it.

[0054] Downhill simulation: When the weight block swings forward, it reduces the rotational load of the drive axle, and may even provide additional rotational inertia, similar to the situation when gravity propels the vehicle while driving downhill.

[0055] In this way, the swing of the weight block can simulate the dynamic process of the load changing with the slope when the vehicle is driving on a slope.

[0056] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A hydraulic drive axle test device characterized by, Hydraulic bridge, uphill and downhill simulation mechanism, power transmission mechanism, the power transmission mechanism is used for transmitting power to the hydraulic bridge, the wheel hub is arranged on the hydraulic bridge, the wheel hub is driven to rotate by the hydraulic bridge, the uphill and downhill simulation mechanism comprises a plurality of movable counterweights and a connecting mechanism, the movable counterweights are rotatably connected to the wheel hub through the connecting mechanism, and the axis of the rotation center of the movable counterweights is parallel to the axis of the rotation center of the wheel hub.

2. The hydraulic drive axle test device of claim 1, wherein, The connecting mechanism comprises a screw rod, a nut and a spacer, a plurality of mounting positions are arranged on the surface of the wheel hub in the circumferential direction, through holes are arranged at the mounting positions and the surface of the movable counterweights, the screw rod is arranged in the through holes of the mounting positions and the movable counterweights, the spacer is arranged between the inner side of the movable counterweight and the outer side of the screw rod, and the nut is used for locking.

3. A hydraulic drive axle test apparatus as in claim 1, wherein, The movable counterweights are arranged in the circumferential direction of the wheel hub, and the mass distribution of the movable counterweights relative to the wheel hub is asymmetrically arranged.

4. A hydraulic drive axle test apparatus as in claim 1, wherein, A plurality of stationary counterweights are further arranged on the wheel hub, and the stationary counterweights are fixedly connected with the wheel hub.

5. A hydraulic drive axle test apparatus as in claim 1, wherein, Through holes are arranged in the center of the stationary counterweights, and the stationary counterweights are fixedly connected with the wheel hub through bolts.

6. A hydraulic drive axle test apparatus as in claim 5, wherein, The movable counterweights and the stationary counterweights are arranged on both sides of the wheel hub.

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