Tire Composite Thermal Expansion Coefficient Measurement System

Abstract

The present invention relates to the field of research on the thermodynamic properties of tire composite materials, and provides a thermal expansion coefficient measurement system for tire composite materials, which includes a main body; a heating box arranged inside the main body; a heating pipe installed on the side wall of the heating box; a measurement table arranged at the bottom of the heating box; a specimen arranged on the measurement table; a front DIC displacement measurement mechanism and a rear DIC displacement measurement mechanism installed on the heating box. It can collect the front view and top view images of the specimen changing with temperature in real time, and thereby obtain the linear expansion coefficient and volume expansion coefficient of the specimen. The system designs a unique rotation and descent mechanism and an electromagnetic retardation device, greatly improving the safety of the equipment, and effectively avoiding damage to the DIC displacement measurement mechanism when the heating box door is opened and closed. The specimen of this system simulates real tire parameters. By analyzing the influence of the cord type and arrangement method on the thermal expansion coefficient of tire composite materials, it can better guide the tire structure design.

Description

Technical Field

[0001] The present invention relates to the field of research on the thermodynamic properties of tire composites, and particularly to a measurement system for the coefficient of thermal expansion of tire composites. Background Art

[0002] Affected by tire materials and forces, a large amount of heat is generated during the repeated driving process of tires, leading to problems such as thermal-oxidative aging and reduced strength. Moreover, when the tires are heated and expand, additional stress and strain will be generated, which will in turn change the force and deformation conditions of the tires, affecting the overall performance of the tires, exacerbating tire damage, and endangering personal safety. Therefore, it is particularly important to study the thermodynamic properties of tire materials, especially the thermal expansion properties of tire materials.

[0003] The coefficient of thermal expansion is a characterization of the thermal expansion performance, and quantitatively characterizes the thermal expansion performance through the rate of change of the length or volume of the material with temperature under isobaric conditions. According to the change in length or volume, the coefficient of thermal expansion is divided into the linear expansion coefficient and the volume expansion coefficient. Among them, the linear expansion coefficient is commonly used to analyze isotropic materials, and the volume expansion coefficient is commonly used to analyze anisotropic materials.

[0004] Tire materials are composite materials, composed of isotropic rubber and cord layers arranged at a certain angle. The linear expansion coefficient can be used to characterize the thermal expansion performance of rubber. However, during the heating process of rubber, glass transition occurs, so its coefficient of thermal expansion is significantly different before and after the glass transition temperature. Compared with rubber, the cord shows completely different material properties, resulting in the composite material having anisotropic thermodynamic behavior. Therefore, the volume expansion coefficient is suitable for characterizing the thermal expansion performance of cord-containing materials. In addition, different types and arrangements of cords will have different effects on the thermodynamic behavior of tire composites, and there are certain requirements for the measuring instruments and specimens of the coefficient of thermal expansion.

[0005] At present, there is no measuring device for the coefficient of thermal expansion of tire composites, and it is impossible to analyze the linear expansion coefficient and the volume expansion coefficient of tire composites, and thus it is impossible to accurately guide the configuration of tire materials, ultimately affecting driving safety. Summary of the Invention

[0006] To solve the problems in the background art, the present invention provides a measurement system for the coefficient of thermal expansion of tire composites, which includes: a main body; a heating box disposed inside the main body; a heating tube installed on the side wall of the heating box; a measuring table disposed at the bottom of the heating box; a specimen disposed on the measuring table; and a DIC displacement measuring mechanism installed on the heating box.

[0007] The DIC displacement measurement mechanism includes a front DIC displacement measurement mechanism arranged at the front of the heating box and a rear DIC displacement measurement mechanism arranged on the top of the heating box; image acquisition devices are installed on both the front DIC displacement measurement mechanism and the rear DIC displacement measurement mechanism.

[0008] The image acquisition device collects the front view and top view images of the specimen changing with temperature in real time, thereby drawing the linear change rate - temperature curve and volume change rate - temperature curve of the specimen, and obtaining the linear expansion coefficient and volume expansion coefficient of the specimen according to the linear change rate - temperature curve and volume change rate - temperature curve.

[0009] Preferably, the specimen includes rubber and cord plies embedded inside the rubber and arranged at a certain angle and spacing, and the types, arrangement angles and spacings of the cord plies simulate the corresponding components of different types of real tires; the thickness of the specimen is the same as the thickness of the corresponding component of the tire; the specimen has been vulcanized under the same vulcanization conditions as the corresponding tire component before measuring the thermal expansion coefficient.

[0010] Preferably, the front DIC displacement measurement mechanism and the DIC displacement measurement mechanism collect the front view and top view images of the specimen changing with temperature in real time, perform image processing and recognition on the images, and obtain the linear change value and volume change value of the specimen at different temperatures. The linear change values include the change values of the length, width and height of the specimen; and calculate the linear change rate and volume change rate according to the initial linear length and initial volume, thereby drawing the linear change rate - temperature curve and volume change rate - temperature curve of the specimen; the slopes of the points on the linear change rate - temperature curve and volume change rate - temperature curve are the linear expansion coefficient and volume expansion coefficient of the specimen.

[0011] In a preferred solution, a box door is arranged in the front view direction of the heating box, and the box door is made of a transparent material.

[0012] Preferably, the main body is provided with a front slide rail and a rear slide rail, and rollers are arranged inside both the front slide rail and the rear slide rail; the bottoms of both the front DIC displacement measurement mechanism and the rear DIC displacement measurement mechanism are sliders, and the sliders are respectively inserted into the front slide rail and the rear slide rail, and the upper and lower surfaces of the sliders are in contact with the outer surfaces of the rollers inside the slide rails, so that the sliders can slide inside the slide rails.

[0013] Preferably, a through hole is formed in the middle of the slider, and a connecting piece is inserted into the through hole and then connected to the slider; a rectangular parallelepiped opening is formed directly above the bottom of the connecting piece, and a convex block is fixedly connected to the right side of the bottom.

[0014] The slider is provided with a sector-shaped groove communicating with the through hole in the middle, and the convex block of the connecting piece is arranged in the sector-shaped groove; an electromagnetic blocking device is installed at the corresponding position of the sector-shaped groove and the rectangular opening of the connecting piece. The electromagnetic blocking device includes a spring and a movable iron core. In the power-off state, the movable iron core is inserted into the rectangular opening of the connecting piece under the action of the spring; after being powered on, the movable iron core contracts under the action of electromagnetic attraction and disengages from the rectangular opening of the connecting piece; the bottom of the sector-shaped groove is concave-shaped, and its size is the same as that of the convex block of the connecting piece.

[0015] Furthermore, the front DIC displacement measurement mechanism includes a connecting piece, a horizontal hydraulic cylinder, a vertical hydraulic cylinder, and an image acquisition device; the top of the connecting piece is connected to a horizontally placed horizontal hydraulic cylinder, the top of the piston rod of the horizontal hydraulic cylinder is welded to the cylinder body of the vertical hydraulic cylinder perpendicular to it, and an image acquisition device is fixedly installed at the top of the piston rod of the vertical hydraulic cylinder.

[0016] Furthermore, the sliders of the front DIC displacement measurement mechanism and the rear DIC displacement measurement mechanism are both equipped with a rotary self-locking structure, which consists of a threaded cylinder and a knob. The threaded cylinder is inserted into the slider, and the knob is located at the top of the threaded cylinder.

[0017] Furthermore, the rear DIC displacement measurement mechanism includes a horizontally placed support plate fixedly connected to the slider. A hydraulic cylinder is welded to the top of the support plate. The hydraulic cylinder includes a vertical cylinder body, a piston rod, and a horizontal cylinder body; wherein, the bottom of the vertical cylinder body is welded to the top of the support plate, and an image acquisition device is fixedly installed at the end of the horizontal cylinder body; the piston rod is formed by welding a vertical rod, a right-angle elbow, and a horizontal rod, and the vertical rod and the horizontal rod are respectively connected to the vertical cylinder body and the horizontal cylinder body.

[0018] Furthermore, a bottom cabinet is also arranged in the main body, and a control panel is installed on the outer wall of the bottom cabinet; inside the bottom cabinet, there are installed the main unit of the DIC displacement measurement mechanism, a motor for providing heat source for the heating pipe, and a control device, and the control device is communicatively connected to the control panel installed on the outer wall of the bottom cabinet.

[0019] The beneficial effects achieved by the present invention are as follows:

[0020] First, the present invention integrates a heating device, a front DIC displacement measurement mechanism, and a rear DIC displacement measurement mechanism, which can collect the front view and top view images of the specimen changing with temperature in real time, perform image processing and recognition on the images, obtain the linear change value and volume change value of the specimen at different temperatures, and calculate the linear change rate and volume change rate according to the initial linear length and initial volume, thereby drawing the linear change rate - temperature curve and volume change rate - temperature curve of the specimen; and obtaining the linear expansion coefficient and volume expansion coefficient of the specimen from this, which has important significance for accurately guiding the tire material configuration.

[0021] Second, the front DIC displacement measurement mechanism of this system is designed with a unique rotating and descending mechanism and an electromagnetic blocking device. By rotating the front DIC displacement measurement mechanism, its height can be changed, greatly improving the safety of the equipment. At the same time, it can effectively avoid touching the front DIC displacement measurement mechanism when the heating chamber door is opened or closed.

[0022] Third, the specimen of this system uses a standard specimen that simulates real tire parameters. Through the analysis of the specimen by this system, the influence of the cord type and arrangement on the thermal expansion coefficient of the tire composite material can be analyzed, which can better guide the tire structure design.

[0023] Fourth, this system has a simple structure, is easy to operate, saves time and effort, and has accurate data. Description of the Drawings

[0024] Figure 1 It is a schematic structural diagram of a measuring instrument for the thermal expansion coefficient of a tire composite material;

[0025] Figure 2 It is a side view of a measuring instrument for the thermal expansion coefficient of a tire composite material;

[0026] Figure 3 It is a front view of a measuring instrument for the thermal expansion coefficient of a tire composite material;

[0027] Figure 4 It is a schematic structural diagram of a C-shaped steel slide rail;

[0028] Figure 5 It is a schematic structural diagram of a front DIC displacement measurement mechanism;

[0029] Figure 6 It is a rear view of a front DIC displacement measurement mechanism;

[0030] Figure 7 It is a side view of a front DIC displacement measurement mechanism;

[0031] Figure 8 It is a schematic structural diagram of a rear DIC displacement measurement mechanism;

[0032] Figure 9 It is a schematic diagram of the specimen used for measurement;

[0033] Figure 10 It is a curve of the linear change rate obtained from the test versus temperature;

[0034] Figure 11 They are curves of the volume change rate obtained from the test versus temperature respectively.

[0035] Reference numerals in the drawings:

[0036] 1. Main body; 2. Heating tube; 3. Specimen; 4. Limiting plate; 5. Front slide rail; 6. Front DIC displacement measuring mechanism; 7. Rear DIC displacement measuring mechanism; 8. Rear slide rail; 9. Control panel; 10. Measuring table; 11. Bottom cabinet; 12. Right side plate; 13. Left side plate; 14. Top plate; 15. Back plate; 16. Heating box; 161. Box door; 31. Rubber; 32. Cord; 51. Cylindrical roller; 61. Horizontal hydraulic cylinder; 62. Vertical hydraulic cylinder; 63. Image acquisition device; 64. Electromagnetic retardation device; 65. Convex block; 66. Rotary self-locking structure; 67. Slide block; 68. Connector; 71. Support plate; 72. Vertical cylinder body; 73. Piston rod; 74. Horizontal cylinder body. Detailed implementation manners

[0037] To facilitate the understanding of those skilled in the art of the present invention, the following describes the specific implementation manners of the present invention with reference to the accompanying drawings. Refer to Figure 1 , 2 , 3, and 4. The present invention provides a measurement system for the thermal expansion coefficient of tire composites, which includes a main body 1. There are two cavities inside the main body 1. The upper part is a heating box 16. A heating tube 2 is installed on the side wall of the heating box 16. A measuring table 10 is arranged at the bottom of the heating box 16. A specimen 3 is placed on the measuring table 10. The heating tube continuously heats the cavity of the heating box 16. A DIC displacement measuring mechanism is installed outside the heating box 16. A box door 161 is arranged in the front view direction of the heating box 16, and the box door 161 is made of a transparent material.

[0038] The main body 1 is composed of an upper box body and a lower bottom cabinet 11 welded through an intermediate measuring table 10. The box body is welded by an opaque left side plate 13, a right side plate 12, a back plate 15 with poor heat transfer performance and a transparent top plate 14 perpendicular to each other in pairs; two mutually perpendicular hollow carbon fiber plates form a limiting plate 4 and are vertically installed on the measuring table 10 in the middle of the main body 1; a heating tube 2 that can emit heat source and light is fixedly installed on the inner walls of the left side plate 13, the right side plate 12 and the back plate 15; the transparent box door 161 is located on the front side of the box body and is fixedly installed on the left side plate 13 through a hinge. The size of the box door is the same as the inner cavity size of the box body to ensure sealing performance; a motor and a micro control device that provide heat source for the heating tube 2 are fixedly installed inside the bottom cabinet 11. The micro control device is connected to a control panel 9 installed on the right side of the front outer wall of the bottom cabinet 11; C-shaped steel front slide rails 5 and rear slide rails 8 are respectively fixedly installed on the top of the front outer wall of the bottom cabinet 11 and the outer wall of the back plate 15. Two rows of cylindrical rollers 51 are installed inside the front slide rail 5 and the rear slide rail 8.

[0039] The DIC displacement measurement system is composed of a front DIC displacement measurement mechanism 6 and a rear DIC displacement measurement mechanism 7 respectively located at the front and top of the main body 1. The bottoms of the front DIC displacement measurement mechanism 6 and the rear DIC displacement measurement mechanism 7 are both rectangular parallelepiped sliders 67. The sliders 67 are respectively embedded in the C-shaped steels of the front slide rail 5 and the rear slide rail 8. The upper and lower surfaces of the sliders 67 just contact the outer surfaces of the rollers 51 in the slide rails, enabling the sliders 67 to slide within the slide rails. Image acquisition devices 63 are installed on both the front DIC displacement measurement mechanism 6 and the rear DIC displacement measurement mechanism 7.

[0040] The front slide rail 5 and the rear slide rail 8 are arranged on the main body 1, and rollers are arranged in both the front slide rail 5 and the rear slide rail 8; the bottoms of the front DIC displacement measurement mechanism 6 and the rear DIC displacement measurement mechanism 7 are both sliders 67. The sliders 67 are respectively embedded in the front slide rail 5 and the rear slide rail 8, and the upper and lower surfaces of the sliders 67 contact the outer surfaces of the rollers in the slide rails, enabling the sliders 67 to slide within the slide rails.

[0041] See Figure 5 、 6 、7. A through hole is opened in the middle of the slider 67. After the connecting piece 68 is inserted into the through hole, it is connected to the slider 67; a rectangular parallelepiped opening is opened directly above the bottom of the connecting piece 68, and a convex block 65 is fixedly connected to the right side of the bottom; a fan-shaped groove communicating with the through hole in the middle is opened in the slider 67, and the convex block 65 of the connecting piece 68 is arranged in the fan-shaped groove; an electromagnetic blocking device 64 is installed at the corresponding position of the fan-shaped groove and the rectangular parallelepiped opening of the connecting piece 68. The electromagnetic blocking device 64 includes a spring and a movable iron core. In the power-off state, the movable iron core is inserted into the rectangular parallelepiped opening of the connecting piece 68 under the action of the spring; after being powered on, the movable iron core contracts under the action of electromagnetic attraction and disengages from the rectangular parallelepiped opening of the connecting piece 68; the bottom of the fan-shaped groove is concave-shaped, and its size is the same as that of the convex block 65 of the connecting piece 68.

[0042] The front DIC displacement measurement mechanism 6 includes a connecting piece 68, a horizontal hydraulic cylinder 61, a vertical hydraulic cylinder 62, and an image acquisition device 63; the top of the connecting piece 68 is connected to a horizontally placed horizontal hydraulic cylinder 61. The top of the piston rod 73 of the horizontal hydraulic cylinder 61 is welded to the cylinder body of the vertical hydraulic cylinder 62 perpendicular to it. The top of the piston rod 73 of the vertical hydraulic cylinder 62 is fixedly installed with an image acquisition device 63.

[0043] In addition, the sliders 67 of the front DIC displacement measurement mechanism 6 and the rear DIC displacement measurement mechanism 7 can optionally be installed with a rotary self-locking structure 66. The rotary self-locking structure 66 is composed of a threaded cylinder and a knob. The threaded cylinder is inserted into the slider 67, and the knob is located at the top of the threaded cylinder.

[0044] The top of the connecting member 68 is welded with a horizontally placed horizontal hydraulic cylinder 61. The top of the piston rod of the horizontal hydraulic cylinder 61 is welded to the cylinder block of the vertical hydraulic cylinder 62. A camera 63 is fixedly installed at the top of the piston rod of the vertical hydraulic cylinder 62, and the camera 63 faces the front of the specimen. Preferably, the specimen 3 includes rubber 31 and cords 32 embedded inside the rubber 31 and arranged at a certain angle and spacing. The types, arrangement angles, and spacings of the cords 32 simulate the corresponding components of different types of real tires; the thickness of the specimen 3 is the same as that of the corresponding components of the tire; the specimen 3 has been vulcanized under the same vulcanization conditions as the corresponding tire components before measuring the coefficient of thermal expansion.

[0045] See Figure 8 , the slider 65 at the bottom of the rear DIC displacement measuring mechanism 7 is welded to a horizontally placed support plate 71. A hydraulic cylinder is welded to the top of the support plate 71. The hydraulic cylinder includes components such as a vertical cylinder block 72, a piston rod 73, and a horizontal cylinder block 74. Among them, the bottom 72 of the vertical cylinder block is welded to the top of the support plate 71. An image acquisition device 63 is fixedly installed at the end of the horizontal cylinder block 74, and the camera 63 faces the top of the specimen; the piston rod 73 is formed by welding a vertical rod, a right-angle elbow, and a horizontal rod. The vertical rod and the horizontal rod are respectively connected to the vertical cylinder block 72 and the horizontal cylinder block 74.

[0046] A base cabinet 11 is also provided inside the main body 1. A control panel 9 is installed on the outer wall of the base cabinet 11; inside the base cabinet 11, a host of the DIC displacement measuring mechanism, a motor for providing heat source for the heating tube 2, and a control device are installed. The control device is communicatively connected to the motor, the electromagnetic retardation device, and the control panel 9 installed on the outer wall of the base cabinet 11. The user can adjust the temperature of the heating box through the control panel 9 and control the operation of the electromagnetic retardation device through the control device. The DIC displacement measuring mechanism is also provided with a driving mechanism connected to the control device to adjust the position of the image acquisition device of the DIC displacement measuring mechanism to ensure a clear image of the specimen is captured.

[0047] Example 1:

[0048] In this example, the measurement process of the tire composite material coefficient of thermal expansion measurement system is as follows: Before the measurement starts, speckles are sprayed on the front and top of the specimen 3. When the transparent door of the main body 1 is opened, at the moment of opening the door, the control device issues an instruction, and the electromagnetic retardation device 64 of the front DIC displacement measuring mechanism 6 is powered on. The movable iron core originally inserted into the connecting member 68 pops out, and then the connecting member 68 rotates under the gravity of the convex block 65 until the convex block 65 is inserted into the bottom of the fan-shaped hole of the slider 67 to prevent the door from touching the front DIC displacement measuring mechanism 6.

[0049] After opening the cabinet door 161, place the specimen 3 closely against the limit plate 4 and horizontally on the measuring table 10, and ensure that the front and top of the speckle sprayed on the specimen 3 face the cameras 63 of the front DIC displacement measuring mechanism 6 and the rear DIC displacement measuring mechanism 7 respectively. Adjust the front DIC displacement measuring mechanism 6 so that the moving iron core of the electromagnetic blocking device 64 is inserted into the connecting piece 68 to keep the front DIC displacement measuring mechanism 6 in a vertical state. Move the sliders 67 of the front DIC displacement measuring mechanism 6 and the rear DIC displacement measuring mechanism 7 so that the two image acquisition devices 63 can face the specimen 3 directly, and rotate the knob of the self-locking structure 66 so that the threaded cylinder rotates and pushes out to contact the C-shaped steel slide rail to fix the slider 67. By adjusting the position of the hydraulic cylinder piston rod, adjust the imaging of the specimen 3 in the camera 63 to ensure clear imaging. Set the temperature and heating rate through the control panel 9, and then close the cabinet door 161 to start the measurement.

[0050] The DIC displacement measurement system records and processes in real time the change rates of the length and volume of the specimen 3 with temperature until the measurement is completed. The specific process includes that the front DIC displacement measuring mechanism 6 and the DIC displacement measuring mechanism collect the front view and top view images of the specimen 3 changing with temperature in real time, and perform image processing and recognition on the images to obtain the linear change values and volume change values of the specimen 3 at different temperatures. The linear change values include the change values of the length, width, and height of the specimen 3; and calculate the linear change rate and volume change rate according to the initial linear length and initial volume, and thus draw the linear change rate - temperature curve of the specimen 3 as Figure 10 shown, and draw the volume change rate - temperature curve as Figure 11 shown. In the Figure 10 linear change rate - temperature curve, Figure 11 the slope of each point in the volume change rate - temperature curve is the linear expansion coefficient and volume expansion coefficient of the specimen 3 at that temperature.

[0051] After the measurement is completed, the electromagnetic blocking device 64 of the front DIC displacement measuring mechanism 6 is powered on, and the originally inserted moving iron core pops out. Subsequently, the connecting piece 68 rotates under the gravity of the convex block 65 until the convex block 65 is inserted into the bottom of the fan-shaped hole of the slider 67. Open the cabinet door 161, take out the specimen and close the cabinet door 161.

[0052] The above embodiments of the present invention do not constitute a limitation to the protection scope of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. Tire composite material thermal expansion coefficient measurement system, characterized in that: It includes: A main body; A heating box arranged inside the main body; A heating pipe installed on the side wall of the heating box; A measuring table arranged at the bottom of the heating box; A specimen arranged on the measuring table; A DIC displacement measurement mechanism installed on the heating box; The DIC displacement measurement mechanism includes a front DIC displacement measurement mechanism arranged at the front of the heating box and a rear DIC displacement measurement mechanism arranged at the top of the heating box; both the front DIC displacement measurement mechanism and the rear DIC displacement measurement mechanism are equipped with image acquisition devices; The image acquisition device real-time collects the front view and top view images of the specimen as the temperature changes, thereby drawing the linear change rate - temperature curve and volume change rate - temperature curve of the specimen, and obtaining the linear expansion coefficient and volume expansion coefficient of the specimen based on the linear change rate - temperature curve and volume change rate - temperature curve; A door is arranged in the front view direction of the heating box; The main body is provided with a front slide rail and a rear slide rail, and rollers are arranged inside both the front slide rail and the rear slide rail; the bottoms of the front DIC displacement measurement mechanism and the rear DIC displacement measurement mechanism are both sliders, and the sliders are respectively inserted into the front slide rail and the rear slide rail, and the upper and lower surfaces of the sliders are in contact with the outer surfaces of the rollers inside the slide rails, so that the sliders can slide inside the slide rails; A through hole is opened in the middle of the slider, and a connecting piece is inserted into the through hole and connected to the slider; a rectangular opening is opened directly above the bottom of the connecting piece, and a convex block is fixedly connected to the right side of the bottom; The slider is provided with a fan-shaped groove communicating with the through hole in the middle, and the convex block of the connecting piece is arranged in the fan-shaped groove; An electromagnetic blocking device is installed at the corresponding position of the fan-shaped groove and the rectangular opening of the connecting piece. The electromagnetic blocking device includes a spring and a movable iron core. In the power-off state, the movable iron core is inserted into the rectangular opening of the connecting piece under the action of the spring; after being powered on, the movable iron core contracts under the action of electromagnetic suction and disengages from the rectangular opening of the connecting piece; subsequently, the connecting piece rotates under the gravity of the convex block until the convex block is inserted into the bottom of the fan-shaped groove of the slider to prevent the door from touching the front DIC displacement measurement mechanism; The bottom of the fan-shaped groove is concave-shaped, and its size is the same as that of the convex block of the connecting piece.

2. The tire composite material thermal expansion coefficient measurement system according to claim 1, characterized in that: The specimen includes rubber and cords embedded inside the rubber and arranged at a certain angle and spacing. The types, arrangement angles and spacings of the cords simulate the corresponding components of different types of real tires; the thickness of the specimen is the same as that of the corresponding components of the tire; the specimen has been vulcanized under the same vulcanization conditions as the corresponding tire components before measuring the thermal expansion coefficient.

3. The tire composite material thermal expansion coefficient measurement system according to claim 1, characterized in that: The front DIC displacement measurement mechanism and the rear DIC displacement measurement mechanism collect the front view and top view images of the specimen changing with temperature in real time, and perform image processing and recognition on the images to obtain the linear change values and volume change values of the specimen at different temperatures. The linear change values include the change values of the length, width, and height of the specimen; and based on the initial linear length and initial volume, the linear change rate and volume change rate are calculated; thereby, the linear change rate-temperature curve and volume change rate-temperature curve of the specimen are plotted; according to the slopes of each point on the linear change rate-temperature curve and volume change rate-temperature curve, the linear expansion coefficient and volume expansion coefficient of the specimen can be obtained.

4. The tire composite material coefficient of thermal expansion measurement system according to claim 1, characterized in that The cabinet door is made of transparent material.

5. The tire composite material thermal expansion coefficient measurement system according to claim 1, wherein: The front DIC displacement measurement mechanism includes a connecting piece, a horizontal hydraulic cylinder, a vertical hydraulic cylinder, and an image acquisition device; a horizontally placed horizontal hydraulic cylinder is connected to the top of the connecting piece, the top of the piston rod of the horizontal hydraulic cylinder is welded to the cylinder body of the vertical hydraulic cylinder perpendicular thereto, and an image acquisition device is fixedly installed at the top of the piston rod of the vertical hydraulic cylinder.

6. The tire composite material thermal expansion coefficient measurement system according to claim 1, wherein: The sliders of the front DIC displacement measurement mechanism and the rear DIC displacement measurement mechanism are both equipped with a rotary self-locking structure, and the rotary self-locking structure is composed of a threaded cylinder and a knob. The threaded cylinder is inserted into the slider, and the knob is located at the top of the threaded cylinder.

7. The tire composite material thermal expansion coefficient measurement system according to claim 1, wherein: The rear DIC displacement measurement mechanism includes a horizontally placed support plate fixedly connected to the slider. A hydraulic cylinder is welded to the top of the support plate. The hydraulic cylinder includes a vertical cylinder body, a piston rod, and a horizontal cylinder body; wherein, the bottom of the vertical cylinder body is welded to the top of the support plate, and an image acquisition device is fixedly installed at the end of the horizontal cylinder body; the piston rod is formed by welding a vertical rod, a right-angle elbow, and a horizontal rod, and the vertical rod and the horizontal rod are respectively connected to the vertical cylinder body and the horizontal cylinder body.

8. The tire composite material thermal expansion coefficient measurement system according to claim 1, wherein: A bottom cabinet is further provided inside the main body, and a control panel is installed on the outer wall of the bottom cabinet; inside the bottom cabinet, a host of the DIC displacement measurement mechanism, a motor for providing heat source for the heating pipe, and a control device are installed, and the control device is communicatively connected to the control panel installed on the outer wall of the bottom cabinet.

Images