Flexure test device and method

Abstract

The invention discloses a deflection test device and method. The deflection test device comprises a side rod pushing system, a pre-tensioning system, a measuring system and a control system, according to the invention, the driving shaft is lifted to lengthen the sample, and preload is applied to the sample, so that the stretching of the tire internal pressure on the material can be simulated, and the actual stress state of the tire material can be reflected; the deflection degree of the sample deflection test can be adjusted by adjusting the displacement of the reciprocating motion of the side rod; according to the invention, by changing the head shape and width of the side rod head, different deflection shapes and non-uniform deformation of the test can be formed, and the real deformation condition of a tire grounding area can be simulated. According to the device, the deflection degree of a sample deflection test can be adjusted, different deflection shapes and non-uniform deformation of the test can be formed, the real deformation condition of a tire grounding area can be simulated, and a test basis is provided for measuring the deflection resistance of materials and structures.

Description

Technical Field

[0001] The present invention relates to the technical field of flexural testing, and in particular to a flexural testing device and method. Background Art

[0002] Whether it is an airplane or a car, tires are an indispensable part of its normal operation. As the only part of an airplane or a car that contacts the ground, the performance of the tire during driving can directly feedback to the whole vehicle, affecting the driving safety, power, stability, smoothness and noise.

[0003] During the use of pneumatic tires, the tires are first inflated to expand to a certain extent, and then they are usually used under periodic stress. When the tire sinks due to load, the tire contact area extends from the tread to the shoulder and even the sidewall, and periodic bending deformation occurs during rolling, and the bending deformation is not uniform.

[0004] The tire is a complex rubber body composed of a cord layer, a buffer layer, a triangular rubber strip, a wire ring, etc. The overall structure is made up of a variety of materials with different properties. The flexural deformation performance of these materials and structures under complex stress conditions will directly determine the safety and life of the tire, so it is necessary to conduct flexural tests on these materials and structures.

[0005] The utility model patent with application number CN2021202827902 discloses a rubber flexural crack testing machine, which can test the performance of rubber in different directions, making the test results more accurate, and can test rubber of different sizes, but it cannot simulate the internal pressure state and non-uniform flexural deformation of the tire in actual working conditions.

[0006] The invention patent with application number 202311721998X discloses a flexural test device and method for aviation tire components. It is mainly for tire components, cutting the tire section, and assembling the whole on a testing machine for flexural performance testing. It cannot test the materials and structures that make up the tire, cannot simulate the inflation pressure state of the tire, and its flexural state is consistent, and cannot simulate non-uniform flexural deformation.

[0007] In order to solve the problems in the prior art that the materials and structures that make up the tire cannot be tested, and the internal pressure state and non-uniform flexural deformation of the tire in actual working conditions cannot be simulated, it is necessary to develop a flexural test device and method to solve the problems. Summary of the invention

[0008] The purpose of the present invention is to design a bending test device and method in order to solve the above problems.

[0009] The present invention achieves the above-mentioned purpose through the following technical solutions: Flexure test device, comprising: A side rod pushing system for pushing the specimen back and forth laterally; the side rod pushing system is installed on one side of the specimen; Pre-tensioning system; the pre-tensioning system includes a crossbeam, a driving shaft, a force sensor, an upper chuck, a lower chuck, and a base. The base is fixedly arranged, the lower chuck is installed on the base, the lower end of the sample is clamped and installed on the lower chuck, the crossbeam is adjustable in position up and down and is placed on the device frame, the driving shaft and the force sensor are both vertically arranged, the driving shaft is adjustable in position up and down and is installed on the crossbeam, the first end of the force sensor is installed on the lower end of the driving shaft, the second end of the force sensor is connected to the upper chuck, and the upper end of the sample is clamped and installed on the upper chuck; Measuring system for measuring the temperature of the specimen or the change of the ambient temperature in the flexure test device; Control system; the control signal output end of the control system is connected to the control signal input end of the side rod propulsion system and the control signal input end of the pre-tensioning system respectively, and the signal output end of the measurement system is connected to the signal input end of the control system.

[0010] Specifically, the side rod pushing system includes a side rod power source, a side rod base, a side rod support, and a side rod. The side rod base is fixed in a fixed position, the side rod support is horizontally adjustable and installed above the side rod base. The side rod is horizontally arranged and horizontally slidably installed in the side rod support. The first end of the side rod is connected to the power output end of the side rod power source, and the second end of the side rod acts on the sample.

[0011] Specifically, the side rod includes a side rod shaft and a side rod head, the first end of the side rod shaft is connected to the power output end of the side rod power source, the second end of the side rod shaft is connected to the tail of the side rod head, and the head of the side rod head acts on the sample.

[0012] As a preference, the head of the side rod head is formed into a plane.

[0013] As another preferred embodiment, the head of the side rod head is formed into an arc surface.

[0014] Preferably, the side rod power source is one of an electric system, a pneumatic system or a hydraulic system.

[0015] Preferably, the measuring system is at least one of a plurality of temperature sensors or a thermal imager. When the measuring system is a plurality of temperature sensors, the plurality of temperature sensors are pasted on the sample.

[0016] Preferably, the control system is a PLC system.

[0017] Preferably, the sample is in the form of a flat sheet.

[0018] The test method of the flexure test device comprises the following steps: a. Lower the crossbeam and driving shaft so that the distance between the upper chuck and the lower chuck is less than the length of the specimen; b. Clamp the sample onto the upper and lower chucks; c. Lift the crossbeam, straighten the specimen, and fix the crossbeam position; d. Lift the driving shaft and stretch the sample. When the pulling force reaches the pulling force calculated according to the tire internal pressure, stop the driving shaft and fix the position of the driving shaft; e. Adjust the position of the side rod support so that the side rod head rests against the specimen; f. Input the displacement value and frequency of the sidebar oscillation into the control system, turn on the sidebar power source, and conduct a flexural test; g. During the test, the longitudinal force, lateral force, temperature and frequency of the sample are collected in real time. When the test achieves the test purpose, the test is stopped.

[0019] The beneficial effects of the present invention are: The present invention elongates the sample by lifting the driving shaft and applying a preload to the sample, thereby simulating the stretching of the material caused by the internal pressure of the tire and reflecting the actual stress state of the tire material. The present invention can adjust the degree of bending of the sample bending test by adjusting the displacement of the reciprocating motion of the side rod; The invention can form different bending shapes and non-uniform deformations of the test by changing the head shape and width of the side rod head, so as to simulate the real deformation condition of the tire contact area.

[0020] The present invention can simulate the stretching of materials caused by the internal pressure of the tire through the innovative design of the pre-tensioning system and the side rod pushing system of the testing machine, can adjust the degree of bending of the sample in the bending test, can form different bending shapes and non-uniform deformation of the test, and simulate the actual deformation of the tire contact area, thereby providing a test basis for measuring the anti-bending performance of materials and structures, and can be used for bending tests of other materials and structures such as leather, rubber, and cord fabric, etc., and has a strong application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The general structure diagram of the tire bending test device of the present invention is shown in FIG. Figure 2 is a schematic diagram of the side rod structure in Example 1; Figure 3 This is a schematic diagram of the side rod structure in Example 2.

[0022] In the figure: 1. side rod base; 2. side rod support; 3. side rod; 301. side rod shaft; 302. side rod head; 4. side rod power source; 5. control system; 6. crossbeam; 7. driving shaft; 8. force sensor; 9. upper chuck; 10. sample; 11. temperature sensor; 12. thermal imager; 13. lower chuck; 14. base. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0026] In the description of the present invention, it should be understood that the terms "upper", "lower", "inside", "outside", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the product of the invention is usually placed when in use, or are directions or positional relationships commonly understood by those skilled in the art. These directions or positional relationships are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0027] Furthermore, the terms “first”, “second”, etc. are merely used for distinguishing descriptions and are not to be understood as indicating or implying relative importance.

[0028] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms such as "setting" and "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings.

[0030] like Figure 1-3 As shown, the bending test device and method include: A side rod 3 pushing system for pushing the sample 10 laterally and reciprocatingly; the side rod 3 pushing system is installed on one side of the sample 10; Pre-tensioning system; the pre-tensioning system includes a crossbeam 6, a driving shaft 7, a force sensor 8, an upper chuck 9, a lower chuck 13, and a base 14. The base 14 is set in a fixed position, the lower chuck 13 is installed on the base 14, the lower end of the sample 10 is clamped and installed on the lower chuck 13, the crossbeam 6 is adjusted up and down and is placed on the device frame, the driving shaft 7 and the force sensor 8 are both vertically arranged, the driving shaft 7 is adjusted up and down and is installed on the crossbeam 6, the first end of the force sensor 8 is installed on the lower end of the driving shaft 7, the second end of the force sensor 8 is connected to the upper chuck 9, and the upper end of the sample 10 is clamped and installed on the upper chuck 9; A measuring system for measuring the temperature of the specimen 10 or the change in ambient temperature in the flexure test apparatus; control system 5; the control signal output end of the control system 5 is connected to the control signal input end of the side rod 3 pushing system and the control signal input end of the pre-tensioning system, and the signal output end of the measuring system is connected to the signal input end of the control system 5.

[0031] like Figure 1 As shown, the side rod 3 pushing system includes a side rod power source 4, a side rod base 1, a side rod support 2, and a side rod 3. The side rod base 1 is set in a fixed position, and the side rod support 2 is installed above the side rod base 1 with an adjustable horizontal position (adjusted to a suitable position to be fixed), the side rod 3 is set horizontally, and the side rod 3 is installed in the side rod support 2 in a horizontally slidable manner. The first end of the side rod 3 is connected to the power output end of the side rod power source 4, and the second end of the side rod 3 acts on the sample 10. The side rod 3 includes a side rod shaft 301 and a side rod head 302. The first end of the side rod shaft 301 is connected to the power output end of the side rod power source 4, and the second end of the side rod shaft 301 is connected to the tail of the side rod head 302. The head of the side rod head 302 acts on the sample 10. The side rod 3 reciprocates and oscillates along its axis, and its oscillating motion is generated by the side rod power source 4. The side rod power source 4 is one of an electric system, a pneumatic system, or a hydraulic system, and can adopt an eccentric wheel method or a reciprocating cylinder or other methods. The width of the side rod head 302 can be greater than or less than the width of the sample 10. The side rod shaft 301 is connected to the power source to transmit reciprocating motion. The displacement and frequency of the side rod 3 are adjustable.

[0032] In some embodiments, Figure 2 As shown, the head of the side rod head 302 is formed into a flat surface.

[0033] In other embodiments, Figure 3As shown, the head of the side rod head 302 is formed into an arc surface. The side rod head 302 adopts an arc-shaped head, and the width L2 of the side rod head 302 can be greater or less than the width of the sample 10 to form different bending degrees and non-uniform bending; in step d of the test procedure, the driving shaft 7 stops when the force lifted to the sample 10 is zero, so as to achieve a bending condition without internal pressure.

[0034] In some embodiments, the measurement system is at least one of a plurality of temperature sensors 11 or a thermal imager 12. When the measurement system is a plurality of temperature sensors 11, the plurality of temperature sensors 11 are attached to the sample 10. The temperature sensors 11 are attached to different parts of the sample 10 to measure the temperature changes at each point during the test; when the measurement system is a thermal imager 12, the dynamic temperature changes of the entire field are measured.

[0035] In some embodiments, the control system 5 is a PLC system or a further control scheme, which controls the operation and operation of the control system 5, as well as the collection and storage of test data. In some embodiments, the sample 10 is in the shape of a flat sheet, or may be in other shapes.

[0036] The test method of the flexure test device comprises the following steps: a. Lower the crossbeam 6 and the driving shaft 7 so that the distance between the upper chuck 9 and the lower chuck 13 is less than the length of the sample 10; b. Clamp the sample 10 onto the upper chuck 9 and the lower chuck 13; c. Lift the beam 6, straighten the sample 10, and fix the position of the beam 6; d. Lift the driving shaft 7 and stretch the sample 10. When the pulling force reaches the pulling force calculated according to the tire internal pressure (the pulling force can also be zero), stop the driving shaft 7 and fix the position of the driving shaft 7; e. Adjust the position of the side rod support 2 so that the side rod head 302 is against the sample 10; f. Input the displacement value and frequency of the oscillation of the side rod 3 in the control system 5, turn on the side rod power source 4, and perform a flexural test; g. During the test, the longitudinal force, lateral force, temperature and frequency of the sample 10 are collected in real time. When the test reaches the test purpose, the test is stopped.

[0037] The tire bending test device of the present invention has a simple structure and is easy to operate. The test method can simulate the internal pressure state and non-uniform bending deformation state of the tire in actual working conditions, providing a basis for measuring the anti-bending performance of materials and structures. The present invention can also be used for bending test specimens 10 of other materials and structures, such as leather, rubber, cord fabric, etc.

[0038] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A flexure test device, characterized in that: include: A side rod pushing system for pushing the specimen back and forth laterally; the side rod pushing system is installed on one side of the specimen; Pre-tensioning system; the pre-tensioning system includes a crossbeam, a driving shaft, a force sensor, an upper chuck, a lower chuck, and a base. The base is fixedly arranged, the lower chuck is installed on the base, the lower end of the sample is clamped and installed on the lower chuck, the crossbeam is adjustable in position up and down and is placed on the device frame, the driving shaft and the force sensor are both vertically arranged, the driving shaft is adjustable in position up and down and is installed on the crossbeam, the first end of the force sensor is installed on the lower end of the driving shaft, the second end of the force sensor is connected to the upper chuck, and the upper end of the sample is clamped and installed on the upper chuck; Measuring system for measuring the temperature of the specimen or the change of the ambient temperature in the flexure test device; Control system; the control signal output end of the control system is connected to the control signal input end of the side rod propulsion system and the control signal input end of the pre-tensioning system respectively, and the signal output end of the measurement system is connected to the signal input end of the control system.

2. The flexure test device according to claim 1, characterized in that: The side rod pushing system includes a side rod power source, a side rod base, a side rod support, and a side rod. The side rod base is set in a fixed position, and the side rod support is installed above the side rod base with an adjustable horizontal position. The side rod is set horizontally and is installed in the side rod support in a horizontally slidable manner. The first end of the side rod is connected to the power output end of the side rod power source, and the second end of the side rod acts on the sample.

3. The flexure test device according to claim 2, characterized in that: The side rod comprises a side rod shaft and a side rod head, the first end of the side rod shaft is connected to the power output end of the side rod power source, the second end of the side rod shaft is connected to the tail of the side rod head, and the head of the side rod head acts on the sample.

4. The flexure test device according to claim 3, characterized in that: The head of the side rod head is formed into a flat surface.

5. The flexure test device according to claim 3, characterized in that: The head of the side rod head is formed into an arc surface.

6. The flexure test device according to claim 2, characterized in that: The side rod power source is one of an electric system, a pneumatic system or a hydraulic system.

7. The flexure test device according to claim 1, characterized in that: The measuring system is at least one of a plurality of temperature sensors or a thermal imager. When the measuring system is a plurality of temperature sensors, the plurality of temperature sensors are pasted on the sample.

8. The flexure test device according to claim 1, characterized in that: The control system is a PLC system.

9. The flexure test device according to claim 1, characterized in that: The sample is in the form of a flat sheet.

10. The testing method of the flexure testing device according to claim 1, characterized in that: The following steps are involved: a. Lower the crossbeam and driving shaft so that the distance between the upper chuck and the lower chuck is less than the length of the specimen; b. Clamp the sample onto the upper and lower chucks; c. Lift the crossbeam, straighten the specimen, and fix the crossbeam position; d. Lift the driving shaft and stretch the sample. When the pulling force reaches the pulling force calculated according to the tire internal pressure, stop the driving shaft and fix the position of the driving shaft; e. Adjust the position of the side rod support so that the side rod head rests against the specimen; f. Input the displacement value and frequency of the sidebar oscillation into the control system, turn on the sidebar power source, and conduct a flexural test; g. During the test, the longitudinal force, lateral force, temperature and frequency of the sample are collected in real time. When the test achieves the test purpose, the test is stopped.

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