A device for measuring the ground contact pressure of a test wheel

Abstract

The utility model relates to the technical field of equipment related to measuring the ground pressure of a test wheel, specifically a device for measuring the ground pressure of a test wheel, comprising a bottom plate and a top plate, wherein telescopic columns are arranged between the four corner ends of the bottom plate and the top plate, a pressure device and a pressure sensor are arranged on the top plate, a test wheel assembly is arranged under the pressure device, the test wheel assembly comprises a test wheel and a fixing member for fixing the test wheel, a plurality of pressure sensors are arranged on the bottom plate, the pressure sensor is connected to a pressure acquisition device, and the pressure acquisition device and the pressure sensor are both connected to a computer. The utility model can monitor the effective contact area and the total bearing capacity value of the test wheel in real time and accurately, calculate the pressure and display the schematic diagram of the pressure distribution, provide a reference for operators to adjust the load, and is simple, intuitive, real-time and accurate, reduces the repetitive operations in conventional methods, and improves the degree of intelligence.

Description

Technical Field

[0001] The utility model relates to the technical field of equipment related to measuring the ground pressure of a test wheel, in particular to a device for measuring the ground pressure of a test wheel. Background Art

[0002] Asphalt mixture rutting test is to measure the deformation rate of rutting formed by the test wheel's reciprocating movement under specified temperature and load conditions. The dynamic stability is expressed as the number of times the test wheel travels for each 1 mm deformation. Numerous studies have shown that dynamic stability can better reflect the ability of asphalt pavement to resist rutting in hot seasons. Asphalt mixture rutting tester is a special equipment for measuring the dynamic stability of asphalt mixture.

[0003] In the T0719-2011 asphalt mixture rutting test of "JTG E20-2011 Highway Engineering Asphalt and Asphalt Mixture Test Procedure", the test wheel ground pressure measurement process is as follows: the measurement is carried out at 60°C, a 50mm thick steel plate is placed on the test bench, a millimeter grid paper is placed on it, and a new carbon paper is placed on it. After the specified 700N load, the test wheel is statically pressed on the carbon paper, and the wheel pressure area can be obtained on the grid paper, and the ground pressure can be obtained from this. When the pressure does not meet 0.7MPa±0.05MPa, the load should be appropriately adjusted.

[0004] When loading or adjusting the load for the first time, the contact area and pressure of the test wheel change with the load size, and the operator needs to repeatedly calculate and count. Therefore, the pressure measurement is a repetitive operation process: place carbon paper and millimeter grid paper before loading, count the effective contact area on the millimeter grid paper after loading, and calculate the pressure according to the loading force value and area; if it does not meet the standard, replace the carbon paper and millimeter grid paper, adjust the load and reload the calculation. This process is time-consuming, inefficient, and consumes a lot of human resources.

[0005] In recent years, domestic enterprises have independently developed some wheel rutting testers. When measuring the ground pressure of the test wheel, some use image recognition devices, and some use laser scanning devices, but most of the devices have complicated structures, complex principles, inaccurate measurement areas, and are easily disturbed.

[0006] Based on the above background technology, it is necessary to provide a new technical solution for measuring the ground contact pressure of the test wheel. Utility Model Content

[0007] In view of the above problems, the utility model provides a device for measuring the ground pressure of a test wheel, which solves the problems of the existing equipment having a cumbersome structure, a complex principle, inaccurate area measurement, and susceptibility to interference.

[0008] The technical solution adopted by the utility model to solve its technical problems is: a device for measuring the ground pressure of a test wheel, comprising a bottom plate and a top plate, telescopic columns are arranged between the four corner ends of the bottom plate and the top plate, a pressure device and a first pressure sensor are arranged on the top plate, a test wheel assembly is arranged under the pressure device, the test wheel assembly comprises a test wheel and a fixing part for fixing the test wheel, a plurality of evenly distributed pressure sensors are arranged on the bottom plate, the plurality of pressure sensors are arranged in an array, the plurality of pressure sensors are connected to a pressure collection device, and the pressure collection device and the pressure sensor are connected to a computer.

[0009] As an optimization, the pressure device includes a hydraulic cylinder and a pressure plate arranged at the output end of the hydraulic cylinder, and guide rods are arranged between the four corner ends of the pressure plate and the top plate.

[0010] As an optimization, the fixing part includes a connecting plate connected to the pressure plate, two relatively arranged fixing plates are slidably provided under the connecting plate, both ends of the fixing plate are provided with through holes with internal threads, bolts are provided in the through holes, and a through opening cooperating with the test wheel is provided at the lower part of the fixing plate, and a connecting column is provided in the through opening.

[0011] As an optimization, a sliding groove is provided on the connecting plate, and a sliding block cooperating with the sliding groove is provided on the fixing plate.

[0012] As an optimization, the slide groove is a T-slot and the slider is a T-block.

[0013] As an optimization, the number of the pressure sensors located in the same row and the number of the pressure sensors located in the same column are both 64.

[0014] The beneficial effects of the utility model are as follows: the utility model provides a device for measuring the ground pressure of a test wheel, which applies pressure to the test wheel through a pressure device, which is used to adjust the load size and apply different pressures to the test wheel. A pressure sensor is arranged under the test wheel, and the pressure sensor integrates an array-distributed force measuring unit for sensing the pressure change of the test wheel. The test wheel contacts the pressure sensor and transmits the loading force value through the effective contact area. The array-type pressure acquisition device is used to collect the real-time force value of the pressure sensor and transmit the signal of the pressure sensor to a computer. The computer is used to summarize the effective contact area of ​​the test wheel, count the total pressure of each force measuring unit, calculate the real-time pressure, and draw a pressure distribution diagram. The device replaces the conventional method of using carbon paper and millimeter grid paper, and can monitor the effective contact area and total bearing capacity of the test wheel in real time and accurately, calculate the pressure and display the pressure distribution diagram, and provide a reference for the operator to adjust the load. The device is simple, intuitive, real-time and accurate, reduces the repetitive operations in the conventional method, and improves the degree of intelligence. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the utility model;

[0016] Figure 2 It is a partial structural schematic diagram of the connecting plate and the fixing plate of the utility model;

[0017] Figure 3 for Figure 2 A schematic diagram of the enlarged structure of part A;

[0018] Figure 4 It is a schematic diagram of the force measuring unit of the pressure sensor;

[0019] Figure 5 Schematic diagram of test wheel pressure distribution when loading 0kg;

[0020] Figure 6 Schematic diagram of test wheel pressure distribution when loaded with 70kg.

[0021] Among them: 1. bottom plate, 2. top plate, 3. telescopic column, 4. test wheel, 5. pressure sensor, 6. hydraulic cylinder, 7. pressure plate, 8. guide rod, 9. connecting plate, 10. fixing plate, 11. bolt, 12. through port, 13. slide groove, 14. slider. DETAILED DESCRIPTION

[0022] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0023] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0024] For the convenience of description, if the words "up", "down", "left" and "right" appear in the present invention, they only indicate that they are consistent with the up, down, left and right directions of the drawings themselves, and do not limit the structure. They are only for the convenience of describing the present invention and simplifying the description, 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 cannot be understood as a limitation on the present invention.

[0025] like Figure 1-3As shown, a device for measuring the ground pressure of a test wheel comprises a bottom plate 1 and a top plate 2, wherein telescopic columns 3 are arranged between the four corner ends of the bottom plate 1 and the top plate 2, wherein the telescopic columns 3 are columns capable of changing their lengths, and the spacing between the bottom plate 1 and the top plate 2 can be adjusted to accommodate test wheels 4 of different sizes, wherein the telescopic structure comprises mechanical, hydraulic, pneumatic, etc., and the implementation forms are diverse and simple for those skilled in the art, and are not described in detail herein; a pressure device and a first pressure sensor are arranged on the top plate 2, wherein the first pressure sensor is used to test the pressure of the pressure device, wherein a test wheel assembly is arranged under the pressure device, wherein the test wheel assembly comprises a test wheel 4 and a fixing member for fixing the test wheel 4, wherein a plurality of uniformly distributed pressure sensors 5 are arranged on the bottom plate 1, wherein the plurality of pressure sensors 5 are arranged in an array, and the area thereof is larger than the bottom surface of the test wheel 4, so as to facilitate testing the pressure from the test wheel 4, wherein the number of the pressure sensors 5 in the same row and the number of the pressure sensors 5 in the same column are both 64, wherein the plurality of pressure sensors 5 are connected to a pressure acquisition device, and the plurality of pressure acquisition devices and pressure sensors are connected to a computer.

[0026] The pressure device is a component that can apply pressure to the test wheel 4. A servo cylinder or a hydraulic cylinder 6 and other components that can apply pressure can be set. In this embodiment, the pressure device includes a hydraulic cylinder 6 and a pressure plate 7 arranged at the output end of the hydraulic cylinder 6. Guide rods 8 are provided between the four corner ends of the pressure plate 7 and the top plate 2. The guide rods 8 pass through the top and bottom of the top plate 2. When the hydraulic cylinder 6 drives the pressure plate 7 to move up and down, the guide rods 8 also move up and down with the pressure plate 7 to increase the stability of the pressure plate 7.

[0027] like Figure 2 and 3 As shown, the fixing member includes a connecting plate 9 connected to the pressure plate 7, and two relatively arranged fixing plates 10 are slidably provided under the connecting plate 9, so that the spacing between the fixing plates 10 can be adjusted for installing test wheels 4 of different sizes. Both ends of the fixing plate 10 are provided with through holes with internal threads, and bolts 11 are provided in the through holes. The bolts 11 are used to achieve the fixation between the fixing plate 10 and the connecting plate 9. After the spacing between the two fixing plates 10 is set according to the size of the test wheel 4, the bolts 11 are screwed to press the connecting plate 9, so as to achieve the fastening between the fixing plate 10 and the connecting plate 9; the lower part of the fixing plate 10 is provided with a through hole 12 that cooperates with the test wheel 4, and a connecting column is provided in the through hole 12.

[0028] The connecting plate 9 is provided with a slide groove 13 , and the fixing plate 10 is provided with a slider 14 matched with the slide groove 13 . The slide groove 13 is a T-shaped groove, and the slider 14 is a T-shaped block.

[0029] Working principle: The utility model provides a device for measuring the ground pressure of a test wheel. When in use, the test wheel 4 is installed between two fixed plates 10, so that the lower surface of the test wheel 4 is placed on the pressure sensor 5, and the pressure device is started to apply pressure to the test wheel 4. The array pressure acquisition device transmits the real-time force value of the pressure sensor 5 to the computer. According to the computer monitoring software measurement results: area, force value, pressure, the load of the loading device can be adjusted at any time until the test conditions are met.

[0030] like Figure 4 The schematic diagram of the force measuring unit of the pressure sensor 5 shown in the figure, the pressure sensor 5 converts the pressure signal into an electrical signal through the force measuring unit array, and then transmits it to the array pressure acquisition device. After amplification and filtering, the analog signal is converted into a digital signal, and the data is uploaded to the computer monitoring software. The computer monitoring software extracts and processes the collected data to calculate the effective contact area, force value and pressure.

[0031] like Figure 5 , Figure 6 As shown, the graphical interface of the computer monitoring software is intuitive and easy to accept, which is convenient for operators to refer to and analyze, accurately adjust the load, and better realize the ground pressure measurement of the test wheel.

[0032] The above-mentioned specific implementation methods are only specific cases of the present utility model. The patent protection scope of the present utility model includes but is not limited to the product form and style of the above-mentioned specific implementation methods. Any appropriate changes or modifications made to them by ordinary technicians in the relevant technical field in accordance with the claims of the present utility model shall fall within the patent protection scope of the present utility model.

Claims

1. A device for measuring the ground contact pressure of a test wheel, characterized in that: It includes a bottom plate and a top plate, telescopic columns are provided between the four corner ends of the bottom plate and the top plate, a pressure device and a first pressure sensor are provided on the top plate, a test wheel assembly is provided under the pressure device, the test wheel assembly includes a test wheel and a fixing part for fixing the test wheel, a plurality of evenly distributed pressure sensors are provided on the bottom plate, the plurality of pressure sensors are arranged in an array, the plurality of pressure sensors are connected to a pressure collection device, and the pressure collection device and the pressure sensor are connected to a computer.

2. The device for measuring the ground contact pressure of a test wheel according to claim 1, characterized in that: The pressure device comprises a hydraulic cylinder and a pressure plate arranged at the output end of the hydraulic cylinder, and guide rods penetrating the top plate from top to bottom are arranged between the four corner ends of the pressure plate and the top plate.

3. The device for measuring the ground contact pressure of a test wheel according to claim 2, characterized in that: The fixing part includes a connecting plate connected to the pressure plate, two fixing plates arranged opposite to each other are slidably provided under the connecting plate, through holes with internal threads are provided at both ends of the fixing plate, bolts are provided in the through holes, a through opening cooperating with the test wheel is provided at the lower part of the fixing plate, a connecting column is provided in the through opening.

4. The device for measuring the ground contact pressure of a test wheel according to claim 3, characterized in that: The connecting plate is provided with a sliding groove, and the fixing plate is provided with a sliding block matched with the sliding groove.

5. The device for measuring the ground contact pressure of a test wheel according to claim 4, characterized in that: The slide groove is a T-shaped groove, and the slide block is a T-shaped block.

6. The device for measuring the ground contact pressure of a test wheel according to claim 1, characterized in that: The number of the pressure sensors located in the same row and the number of the pressure sensors located in the same column are both 64.

Images