Vehicle frame torsional rigidity testing device and testing method

Abstract

The invention discloses a vehicle frame torsional rigidity testing device and method, and belongs to the technical field of vehicle frame torsional rigidity tests.The testing device comprises supporting beams fixed to a front suspension and a rear suspension of a vehicle frame and supporting sleeves corresponding to the supporting beams, and the supporting beams are provided with two sliding grooves symmetrical about the axis of the supporting beams; a sliding block is slidably installed in the sliding groove in a limited mode, a first spring is fixedly connected between the sliding block and the two opposite side walls of the sliding groove, an installation sleeve is slidably installed in the supporting sleeve, a second spring is fixedly connected between the installation sleeve and the inner wall of the supporting sleeve, a threaded rod is connected into the installation sleeve in a threaded mode, and a supporting plate is rotationally connected to the top end of the threaded rod. The connecting rod abuts against the supporting plate, a pressure sensor is installed between the mounting sleeve and the bottom wall of the supporting sleeve, and a loading mechanism is fixedly installed on the experiment site close to the front suspension side of the frame. According to the invention, fatigue deformation of a connection point of the support beam and the frame caused by overlarge output displacement of the loading mechanism can be avoided, so that a test result is closer to an actual vehicle condition.

Description

Technical Field

[0001] The present invention belongs to the technical field of frame torsional stiffness testing, and particularly relates to a frame torsional stiffness testing device and a testing method. Background Art

[0002] Torsional stiffness is one of the performance requirements that the frame structure must meet. During the development process of vehicle products, it is necessary to test the torsional stiffness of the frame structure to evaluate whether the developed frame structure meets the torsional stiffness performance requirements. Therefore, the frame structure torsional stiffness testing system is an essential device for developing passenger vehicle products. The constraint and loading device is the main device of the frame structure torsional stiffness testing system.

[0003] Currently, the commonly used testing method is to conduct a static stiffness test on the frame. The frame is fixed and supported on the rear suspension through two rear suspension constraint clamps, and a loader is used to load the front suspension to drive the rotation of the ordinary passenger vehicle frame around the rotation axis of the rotating T-beam for testing. Since the rear suspension of the frame is fixed, when rotating the front suspension, it is necessary to limit the displacement output by the loader. If the displacement output by the loader is too large, it will cause fatigue deformation at the connection point between the rear suspension and the rear suspension constraint clamp or cause non-linear deformation of the frame, thus affecting the accuracy of the torsional test. At the same time, due to the actual operating environment of the vehicle, when encountering a relatively high slope or obstacle height, when a relatively high obstacle is encountered at the front side of the vehicle, the corresponding position at the rear side of the vehicle will be raised. Therefore, the current static stiffness testing method cannot accurately reflect the actual torsional stiffness of the whole vehicle.

[0004] Therefore, it is necessary to propose a frame torsional stiffness testing device and a testing method to solve the above problems. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a frame torsional stiffness testing device and a testing method, which are used to solve the problems in the prior art that the fixed method for the rear suspension results in a low range of frame torsional stiffness testing and cannot accurately reflect the actual torsional stiffness of the whole vehicle.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] The present invention provides a test device for the torsional stiffness of a vehicle frame, comprising: two support beams fixedly connected to the vehicle frame, and support sleeves fixedly installed on the experimental site corresponding to the support beams. One of the two support beams is fixedly connected to the front suspension of the vehicle frame, and the other of the two support beams is fixedly connected to the rear suspension of the vehicle frame. The support beam is provided with two chutes symmetrically arranged about the axis of the support beam on the side away from the vehicle frame. The axis connection lines of the four chutes form a rectangle. A slider is slidably installed in the chute in a limited manner. A first spring in a compressed state is fixedly connected between the slider and the opposite side walls of the chute. An installation sleeve is slidably installed in the support sleeve. A second spring is fixedly connected between the installation sleeve and the inner wall of the support sleeve. A screw rod is threadedly connected to the installation sleeve. The top end of the screw rod is rotatably connected to a support plate. The connecting rod abuts against the support plate. A pressure sensor for monitoring the pressure received by the installation sleeve is installed between the installation sleeve and the bottom wall of the support sleeve. Among them, a loading mechanism for driving the support beam on the front suspension of the vehicle frame to rotate is fixedly installed on the experimental site near the front suspension side of the vehicle frame.

[0008] Further, a displacement sensor for monitoring the displacement of the slider is installed in the chute.

[0009] Further, a plurality of force sensors are arranged side by side on the lower surfaces of the longitudinal beams on both sides of the vehicle frame, and two force sensors correspond to each other one by one.

[0010] A test method for a test device for the torsional stiffness of a vehicle frame includes the following steps:

[0011] S1: Use a lifting device to hoist the vehicle frame into the air, and then fixedly install the two support beams 1 on the front suspension and the rear suspension of the vehicle frame respectively;

[0012] S2: Drive the slider 3 to move through a driving mechanism so that the slider 3 is located in the middle of the chute 2. At this time, the displacement of the slider 3 monitored by the displacement sensor is zero;

[0013] S3: Rotate the screw rod 9 so that the support plates 10 in the four support sleeves 6 are at the same height and the pressures in the four pressure sensors are the same;

[0014] S4: Use a lifting device to hoist the vehicle frame above the support sleeve 6, so that the four connecting rods 5 respectively slide into the corresponding support sleeves 6, and the connecting rods 5 support on the support plates 10;

[0015] S5: Establish multiple test conditions by adjusting the center of gravity of the vehicle frame, and respectively rotate the screw rod 9 to adjust the height of the support plate 10 to meet the preset conditions;

[0016] S6: Implement a loading test. Drive the support beam 1 fixed on the front suspension of the vehicle frame to rotate by a preset angle through the loading mechanism 11, and calculate the torsional stiffness of the vehicle frame according to the values of the four pressure sensors.

[0017] Further, the multiple test conditions in step S5 include:

[0018] Condition 1: The center of gravity of the frame is biased towards the left side of the front suspension of the frame. By rotating the screw on the left front side, the height of the support plate on the left front side is made lower than the heights of the other support plates.

[0019] Condition 2: The center of gravity of the frame is biased towards the right side of the front suspension of the frame. By rotating the screw on the right front side, the height of the support plate on the right front side is made lower than the heights of the other support plates.

[0020] Condition 3: The center of gravity of the frame is biased towards the left side of the rear suspension of the frame. By rotating the screw on the left rear side, the height of the support plate on the left rear side is made lower than the heights of the other support plates.

[0021] Condition 4: The center of gravity of the frame is biased towards the right side of the rear suspension of the frame. By rotating the screw on the right rear side, the height of the support plate 10 on the right rear side is made lower than the heights of the other support plates.

[0022] Condition 5: The center of gravity of the frame is biased towards the front suspension side of the frame. By rotating the two screws on the front side, the heights of the two support plates on the front side are made the same and lower than the heights of the two support plates on the rear side.

[0023] Condition 6: The center of gravity of the frame is biased towards the rear suspension side of the frame. By rotating the two screws on the rear side, the heights of the two support plates on the rear side are made the same and lower than the heights of the two support plates on the front side.

[0024] Condition 7: The center of gravity of the frame is biased towards the left side of the frame. By rotating the two screws on the left side, the heights of the two support plates on the left side are made the same and lower than the heights of the two support plates on the right side.

[0025] Condition 8: The center of gravity of the frame is biased towards the right side of the frame. By rotating the two screws on the right side, the heights of the two support plates on the right side are made the same and lower than the heights of the two support plates on the left side.

[0026] Further, in step S6, the torsional stiffness K of the frame is calculated by the following formula:

[0027]

[0028] Among them, the loading mechanism is arranged close to the left side of the front suspension of the frame. L is the distance between the two connecting rods along the extension direction of the support beam. F1 is the value of the pressure sensor located on the left side of the front suspension of the frame. F2 is the value of the pressure sensor located on the right side of the front suspension of the frame. F3 is the value of the pressure sensor located on the left side of the rear suspension of the frame. F4 is the value of the pressure sensor located on the right side of the rear suspension of the frame. L0 is the sum of the values of the two displacement sensors on the support beam of the front suspension. L1 is the sum of the values of the two displacement sensors on the support beam of the rear suspension.

[0029] The beneficial effects of the present invention are as follows:

[0030] In the present invention, the connecting rod abuts against the support plate, so that when the loading mechanism outputs displacement, the connecting rod can be driven to move, avoiding fatigue deformation of the connection point between the support beam and the vehicle frame caused by excessive output displacement of the loading mechanism; breaking the output displacement limit of the loading mechanism and increasing the test range; and by rotating the screw rod, the center of gravity position of the vehicle frame can be adjusted to adapt to a variety of different test conditions, making the test results closer to the actual vehicle condition and improving the accuracy of the test.

[0031] Other advantages, objectives and features of the present invention will be described in the following specification, and to some extent will be obvious to those skilled in the art, or those skilled in the art can obtain teachings from the practice of the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to make the objectives, technical solutions and beneficial effects of the present invention clearer, the following drawings are provided for description of the present invention:

[0033] Figure 1 It is a schematic diagram of the overall structure of the test device according to an embodiment of the present invention;

[0034] Figure 2 It is a schematic diagram of the enlarged partial structure of the test device according to an embodiment of the present invention.

[0035] The reference signs in the drawings are as follows: support beam 1, chute 2, slider 3, first spring 4, connecting rod 5, support sleeve 6, mounting sleeve 7, second spring 8, screw rod 9, support plate 10, loading mechanism 11. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] As Figures 1-2As shown in the figure, the present invention provides a frame torsional stiffness testing device, which includes: two support beams 1 fixedly connected to the frame, and support sleeves 6 fixedly installed on the test site and connected to the support beams 1. One of the two support beams 1 is fixedly connected to the front suspension of the frame, and the other of the two support beams 1 is fixedly connected to the rear suspension of the frame. On the side of the support beam 1 away from the frame, there are two chutes 2 symmetric about the axis of the support beam 1. The axis connection lines of the four chutes 2 form a rectangle. A slider 3 is installed in the chute 2 in a limited sliding manner. A first spring 4 in a compressed state is fixedly connected between the slider 3 and the opposite side walls of the chute 2. A displacement sensor for monitoring the displacement of the slider 3 is installed in the chute 2. The side of the slider 3 away from the support beam 1 is hinged with a connecting rod 5. The connecting rod 5 is slidably connected in the support sleeve 6. An installation sleeve 7 is slidably installed in the support sleeve 6. A second spring 8 is fixedly connected between the installation sleeve 7 and the bottom wall of the support sleeve 6. A screw rod 9 is threadedly connected in the installation sleeve 7. The top end of the screw rod 9 is rotatably installed with a support plate 10. The connecting rod 5 abuts against the support plate 10. A pressure sensor for monitoring the pressure received by the installation sleeve 7 is installed between the installation sleeve 7 and the bottom wall of the support sleeve 6. Among them, on the test site near the front suspension side of the frame, a loading mechanism 11 for driving the rotation of the support beam on the front suspension is fixedly installed. The loading mechanism 11 includes but is not limited to a cylinder or a hydraulic cylinder.

[0037] In this solution, when using this frame torsional stiffness testing device for testing, it includes the following steps:

[0038] S1: Use a lifting device to hoist the frame to be suspended, and then fixedly install the two support beams 1 on the front suspension and the rear suspension of the frame respectively;

[0039] S2: Drive the slider 3 to move through a driving mechanism so that the slider 3 is located in the middle of the chute 2. At this time, the displacement of the slider 3 monitored by the displacement sensor is zero;

[0040] S3: Rotate the screw rod 9 to make the support plates 10 in the four support sleeves 6 at the same height and the pressures in the four pressure sensors consistent;

[0041] S4: Use a lifting device to hoist the frame above the support sleeve 6, so that the four connecting rods 5 respectively slide into the corresponding support sleeves 6, and make the connecting rods 5 support on the support plates 10;

[0042] S5: Establish multiple test conditions by adjusting the center of gravity of the frame, and respectively rotate the screw rod 9 to adjust the height of the support plate 10 to meet the preset conditions;

[0043] Among them, the multiple test conditions include:

[0044] Condition 1: The center of gravity of the vehicle frame is biased towards the left side of the front suspension of the vehicle frame. By rotating the screw 9 on the left front side, the height of the support plate 10 on the left front side is made lower than the height of the other support plates 10.

[0045] Condition 2: The center of gravity of the vehicle frame is biased towards the right side of the front suspension of the vehicle frame. By rotating the screw 9 on the right front side, the height of the support plate 10 on the right front side is made lower than the height of the other support plates 10.

[0046] Condition 3: The center of gravity of the vehicle frame is biased towards the left side of the rear suspension of the vehicle frame. By rotating the screw 9 on the left rear side, the height of the support plate 10 on the left rear side is made lower than the height of the other support plates 10.

[0047] Condition 4: The center of gravity of the vehicle frame is biased towards the right side of the rear suspension of the vehicle frame. By rotating the screw 9 on the right rear side, the height of the support plate 10 on the right rear side is made lower than the height of the other support plates 10.

[0048] Condition 5: The center of gravity of the vehicle frame is biased towards the front suspension side of the vehicle frame. By rotating the two screws 9 on the front side, the heights of the two support plates 10 on the front side are made the same and lower than the heights of the two support plates 10 on the rear side.

[0049] Condition 6: The center of gravity of the vehicle frame is biased towards the rear suspension side of the vehicle frame. By rotating the two screws 9 on the rear side, the heights of the two support plates 10 on the rear side are made the same and lower than the heights of the two support plates 10 on the front side.

[0050] Condition 7: The center of gravity of the vehicle frame is biased towards the left side of the vehicle frame. By rotating the two screws 9 on the left side, the heights of the two support plates 10 on the left side are made the same and lower than the heights of the two support plates 10 on the right side.

[0051] Condition 8: The center of gravity of the vehicle frame is biased towards the right side of the vehicle frame. By rotating the two screws 9 on the right side, the heights of the two support plates 10 on the right side are made the same and lower than the heights of the two support plates 10 on the left side.

[0052] S6: Implement the loading test. Drive the support beam 1 fixed on the front suspension of the vehicle frame to rotate a preset angle through the loading mechanism 11, and calculate the torsional stiffness of the vehicle frame according to the values of the four pressure sensors.

[0053] Among them, the torsional stiffness K of the vehicle frame is calculated by the following formula:

[0054]

[0055] Among them, the loading mechanism 11 is arranged close to the left side of the front suspension of the vehicle frame. L is the distance between two connecting rods 5 along the extending direction of the support beam 1. F1 is the value of the pressure sensor located on the left side of the front suspension of the vehicle frame. F2 is the value of the pressure sensor located on the right side of the front suspension of the vehicle frame. F3 is the value of the pressure sensor located on the left side of the rear suspension of the vehicle frame. F4 is the value of the pressure sensor located on the right side of the rear suspension of the vehicle frame. L0 is the sum of the values of two displacement sensors on the support beam 1 of the front suspension. L1 is the sum of the values of two displacement sensors on the support beam 1 of the rear suspension.

[0056] During the test, define the hinge point between the connecting rod 5 close to the loading mechanism 11 on the front suspension and the support beam 1 as hinge point a, and the hinge point between the connecting rod 5 far from the loading mechanism 11 on the front suspension and the support beam 1 as hinge point b. Define the hinge point between the connecting rod 5 on the rear suspension and the support beam 1, which is in the same longitudinal direction as hinge point a, as hinge point c, and the hinge point between the connecting rod 5 on the rear suspension and the support beam 1, which is in the same longitudinal direction as hinge point b, as hinge point d. When the output displacement of the loading mechanism 11 is within the preset interval, the connecting rod 5 close to the loading mechanism 11 on the front suspension rises, that is, hinge point a rises, causing the support beam 1 fixed to the front suspension to rotate around hinge point b, and hinge point b moves downward under the turning pressure. When the output displacement of the loading mechanism 11 exceeds the preset interval, the connecting rod on the front suspension close to the loading mechanism 11 rises, that is, hinge point a rises, causing the support beam 1 fixed to the front suspension to rotate around hinge point b, and hinge point b moves upward under the output action of the loading mechanism 11. The left extreme value of the preset interval is zero, and the right extreme value of the preset interval is the demarcation value that can cause the connecting rod 5 far from the loading mechanism 11 on the support beam 1 fixed to the front suspension to rise or fall.

[0057] In this solution, the connecting rod 5 abuts against the support plate 10, so that when the loading mechanism 11 outputs displacement, it can drive the connecting rod 5 to move, avoiding fatigue deformation of the connection point between the support beam 1 and the vehicle frame caused by excessive output displacement of the loading mechanism 11; breaking the output displacement limit of the loading mechanism 11 and improving the test range; and by rotating the screw rod 9, the center of gravity position of the vehicle frame can be adjusted to adapt to a variety of different test conditions, making the test results closer to the actual vehicle condition and improving the test accuracy.

[0058] In an embodiment of the present invention, a plurality of force sensors are arranged side by side on the lower surfaces of the longitudinal beams on both sides of the vehicle frame, and the force sensors on both sides correspond one by one. The accuracy of the test is improved by averaging the values sensed by each force sensor.

[0059] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A vehicle frame torsional stiffness test device, characterized in that, Comprising: Two support beams fixedly connected to the vehicle frame, and support sleeves fixedly installed on the test site corresponding to the support beams. One of the two support beams is fixedly connected to the front suspension of the vehicle frame, and the other of the two support beams is fixedly connected to the rear suspension of the vehicle frame. The support beam is provided with two chutes symmetrically arranged about the axis of the support beam on the side away from the vehicle frame. The axis connection lines of the four chutes form a rectangle. A slider is installed in the chute in a limited sliding manner. A first spring in a compressed state is fixedly connected between the slider and the opposite side walls of the chute. An installation sleeve is slidably installed in the support sleeve. A second spring is fixedly connected between the installation sleeve and the inner wall of the support sleeve. A screw rod is threadedly connected to the installation sleeve. The top end of the screw rod is rotatably connected to a support plate. The connecting rod abuts against the support plate. A pressure sensor for monitoring the pressure received by the installation sleeve is installed between the installation sleeve and the bottom wall of the support sleeve. Among them, a loading mechanism for driving the support beam on the front suspension to rotate is fixedly installed on the test site near the front suspension side of the vehicle frame.

2. The frame torsional stiffness testing device according to claim 1, wherein: A displacement sensor for monitoring the displacement of the slider is installed in the chute.

3. The vehicle frame torsional stiffness testing device according to claim 2, wherein: A plurality of force sensors are arranged side by side on the lower surfaces of the longitudinal beams on both sides of the vehicle frame, and two force sensors correspond to each other one by one.

4. The testing method of the vehicle frame torsional stiffness testing device according to claim 3, characterized in that Including the following steps: S1: Use a lifting device to hoist the vehicle frame to be suspended, and then fixedly install the two support beams 1 on the front suspension and the rear suspension of the vehicle frame respectively; S2: Drive the slider 3 to move through a driving mechanism so that the slider 3 is located in the middle of the chute 2. At this time, the displacement of the slider 3 monitored by the displacement sensor is zero; S3: Rotate the screw rod 9 so that the support plates 10 in the four support sleeves 6 are at the same height and the pressures in the four pressure sensors are the same; S4: Use a lifting device to hoist the vehicle frame above the support sleeve 6, so that the four connecting rods 5 respectively slide into the corresponding support sleeves 6, and the connecting rods 5 support on the support plates 10; S5: Establish a plurality of test conditions by adjusting the center of gravity of the vehicle frame, and respectively rotate the screw rod 9 to adjust the height of the support plate 10 to meet the preset conditions; S6: Implement a loading test. Drive the support beam 1 fixed on the front suspension of the vehicle frame to rotate by a preset angle through the loading mechanism 11, and calculate the torsional stiffness of the vehicle frame according to the values of the four pressure sensors.

5. The testing method of the vehicle frame torsional stiffness testing device according to claim 4, characterized in that, The multiple test conditions in step S5 include: Condition 1, the center of gravity of the vehicle frame deviates to the left side of the front suspension of the vehicle frame. By rotating the screw rod on the left front side, the height of the support plate on the left front side is lower than the heights of the other support plates; Condition 2, the center of gravity of the vehicle frame deviates to the right side of the front suspension of the vehicle frame. By rotating the screw rod on the right front side, the height of the support plate on the right front side is lower than the heights of the other support plates; Condition 3, the center of gravity of the vehicle frame deviates to the left side of the rear suspension of the vehicle frame. By rotating the screw rod on the left rear side, the height of the support plate on the left rear side is lower than the heights of the other support plates; Condition 4, the center of gravity of the vehicle frame deviates to the right side of the rear suspension of the vehicle frame. By rotating the screw rod on the right rear side, the height of the support plate 10 on the right rear side is lower than the heights of the other support plates; Condition 5, the center of gravity of the vehicle frame deviates to the front suspension side of the vehicle frame. By rotating the two screw rods on the front side, the heights of the two support plates on the front side are the same and lower than the heights of the two support plates on the rear side; Condition 6: The center of gravity of the frame is biased towards the rear suspension side of the frame. By rotating the two screws at the rear side, the heights of the two support plates at the rear side are made the same and lower than the heights of the two support plates at the front side. Condition 7: The center of gravity of the frame is biased towards the left side of the frame. By rotating the two screws on the left side, the heights of the two support plates on the left side are made the same and lower than the heights of the two support plates on the right side. Condition 8: The center of gravity of the frame is biased towards the right side of the frame. By rotating the two screws on the right side, the heights of the two support plates on the right side are made the same and lower than the heights of the two support plates on the left side.

6. The testing method of the vehicle frame torsional stiffness testing device according to claim 5, characterized in that, In step S6, the torsional stiffness K of the frame is calculated by the following formula: Among them, the loading mechanism is arranged near the left side of the front suspension of the frame. L is the distance between the two connecting rods along the extension direction of the support beam. F1 is the value of the pressure sensor located on the left side of the front suspension of the frame. F2 is the value of the pressure sensor located on the right side of the front suspension of the frame. F3 is the value of the pressure sensor located on the left side of the rear suspension of the frame. F4 is the value of the pressure sensor located on the right side of the rear suspension of the frame. L0 is the sum of the values of the two displacement sensors on the support beam of the front suspension. L1 is the sum of the values of the two displacement sensors on the support beam of the rear suspension.

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