CN102539264B - Assessing test machine for tribological properties of high polymer compound material - Google Patents

Abstract

The invention relates to a test machine for evaluating the tribological performance of polymer composite materials, which comprises a closed box body, and is characterized in that: a transmission shaft is arranged on the box body wall, and the shaft end of the transmission shaft extends out of the box body. The safety shaft, torque meter, and servo motor are connected in sequence with a coupling, and a rotation angle disk is installed on the safety shaft; one end of the transmission shaft extending into the box is connected with the sample shaft through a universal cross coupling, and surrounds the The sample shaft is equipped with an upper sample clamp and a lower sample clamp. The upper sample clamp is connected with a dowel rod. A displacement measuring rod in contact with the displacement sensor is installed on the rod extension. Its advantages are: it can simulate the real working conditions of the polymer composite material, conduct the tribological performance evaluation experiment of the polymer composite material, and detect the wear amount of the polymer composite material and the change of the friction coefficient with time in real time.

Description

Tribological Performance Evaluation Experimental Machine for Polymer Composite Materials

technical field

The invention relates to the field of machinery, in particular to a test machine for evaluating the tribological performance of high polymer composite materials, which can detect the tribological performance of high polymer composite materials under different loads, different swing speeds and different ambient temperatures.

Background technique

Functional polymer composite materials used in self-lubricating joint bearings, self-lubricating bushings and self-lubricating guide rails rely on the transfer film formed by the polymer (such as polytetrafluoroethylene) on the surface and the dual pair (metal) to achieve friction reduction. Relying on the synergistic effect of its matrix (such as phenolic resin, polyimide resin) and polymer reinforcement materials (such as aramid fiber, glass fiber, carbon fiber) doped in the matrix to achieve wear resistance.

Experimental machines for polymer composite materials such as "Low-speed Heavy-duty Fiber Braided Composite Self-lubricating Liner Performance Tester" (Chinese Patent ZL200810079552.0) disclose a fiber-woven composite used in low-speed and heavy-duty working conditions Self-lubricating pad performance testing machine, "High-speed light-load fiber braided composite self-lubricating pad performance testing machine" (Chinese patent ZL200810079554.X) discloses a fiber braided composite self-lubricating application in high-speed and light-load conditions In the gasket performance testing machine, the outer sphere used as the dual pair in the above patent is fixedly connected at both ends and simply supported in the middle of the rotating shaft of the box. When replacing the dual pair, the bearing and the rotating shaft need to be removed from one end of the box, and the test time is large. At the same time, in the process of sample preparation, the fiber braided composite needs to be bonded to the inner spherical surface of the fixture, the process is complicated, and the bonding quality is difficult to guarantee. A test machine for self-lubricating joint bearings and other parts, such as the document "Development of Bearing Wear Tester", proposes a test machine for joint bearings, such as "Helicopter Main Rotor Spherical Joint Bearing Fatigue Test Machine" (Chinese patent ZL200810079553. 5) discloses a fatigue testing machine applied to the main rotor system of a helicopter.

At present, parts with functional polymer composite materials as friction pairs are mostly used in special working conditions, such as high-speed light load, low-speed heavy load, reciprocating swing, high temperature, low temperature, etc., which are difficult to achieve or close to in conventional commercial testing machines. The working conditions of components, the evaluation of tribological properties of functional polymer composites and the development of experimental devices have attracted more and more attention.

Contents of the invention

The purpose of the present invention is to improve the friction and wear performance of high polymer composite materials in order to meet the requirements of engineering applications and the development and evaluation of high polymer composite materials, and provide a kind of experimental machine for testing the tribological properties of high polymer composite materials. Load, swing speed, ambient temperature and other working conditions to test the tribological properties of polymer composite materials.

The technical solution adopted by the present invention to solve its technical problems is as follows:

The present invention comprises a closed box body, a transmission shaft is supported by a bearing group on the box body wall, and the shaft end of the transmission shaft protruding from one end of the box body is connected with the output end of the safety shaft through a coupling, The input end of the safety shaft is connected to the output shaft of the torque meter through a coupling, and the input shaft of the torque meter is connected to the output shaft of the servo motor through a coupling. A rotation angle disk is installed on the safety shaft, and the surface of the rotation angle disk There are two circular arc grooves symmetrically on the top, and the first iron stopper and the second iron stopper are respectively arranged in the two arc grooves. In the radial direction, the first travel switch and the first travel switch are installed on both sides of the rotary angle plate. The second travel switch; the shaft end of the transmission shaft extending into the box is connected to the sample shaft through a universal cross coupling, and an upper sample clamp and a lower sample clamp are arranged around the sample shaft. The sample fixture is connected with a dowel bar, one end of the dowel bar extends out of the box, and there is a bearing set between the dowel bar and the box wall to support, and the end of the dowel bar protruding out of the box is installed with a heat-insulating shaft. The pressure sensor is in contact with the force-measuring end of a pressure sensor, and the pressure sensor is fixedly connected to the piston of a hydraulic cylinder. A displacement measuring rod is installed on the extending part of the dowel rod, and the displacement measuring rod is in contact with the displacement sensor.

The axes of the transmission shaft and the dowel rod are located in the same plane and are perpendicular to each other;

There is a seal between the transmission shaft and the wall of the closed box, and there is a seal between the dowel and the wall of the closed box;

A high-temperature heater, a low-temperature refrigerator and an environment box temperature sensor are arranged in the box.

The beneficial effects of the present invention are: the present invention can simulate the real working conditions of the polymer composite material, including load, swing speed, temperature, etc.; it can conduct the tribological performance evaluation experiment of the polymer composite material, and can detect the high polymer composite material in real time. The wear amount and friction coefficient of composite materials change with time. At the same time, it has the advantages of simple sample preparation, easy standardization, convenient disassembly and assembly, and high experimental efficiency. the

Description of drawings

Fig. 1 is a structural schematic diagram of the experimental machine for evaluating the tribological properties of polymer composite materials;

Fig. 2 is the A-A direction view of Fig. 1;

Figure 3 is a sample diagram.

In the figure: 1. Servo motor, 2. First coupling, 3. Torque meter, 4. Second coupling, 5. Rotation angle disc, 6. First limit switch, 7. Third coupling Device, 8. Closed box, 9. Drive shaft, 10. First seal, 11. First box hole, 12. First bearing group, 13. Cross shaft universal coupling, 14. Safety shaft , 15. dowel bar, 16. upper sample fixture, 17. upper sample, 18. sample shaft, 19. lower sample fixture, 20. support seat, 21. lower sample, 22. lower sample temperature Sensor, 23. Upper sample temperature sensor, 24. Second seal, 25. Second bearing group, 26. Second box hole, 27. Heat insulation shaft, 28. Displacement sensor, 29. Pressure sensor, 30. Load hydraulic cylinder, 31. high temperature heater, 32. low temperature refrigerator, 33. environment box temperature sensor, 34. first iron stopper, 35. displacement measuring rod, 36. second iron stopper, 37. second travel switch.

Detailed ways

Fig. 1, Fig. 2 and Fig. 3 are an embodiment disclosed by the present invention, two holes are opened on the airtight box body 8: the first box body hole 11 and the second box body hole 26. The axes of the first box hole 11 and the second box hole 26 are located in a plane and are perpendicular to each other. The first box hole 11 supports the transmission shaft 9 through the first bearing group 12, and one end of the transmission shaft 9 extends outside the airtight box 8, and the end of the extended end of the transmission shaft 9 is connected to the safety shaft through the third coupling 7. 14 is connected to the output end, the input end of the safety shaft 14 is connected to the output shaft of the torque meter 3 through the second coupling 4, and the input shaft of the torque meter 3 is connected to the output shaft of the servo motor 1 through the first coupling 2. The rotation angle disc 5 is installed and fixedly connected to the output end of the safety shaft 14, and two arc grooves are symmetrically opened on the disc surface of the rotation angle disc, and the first iron stopper 34 and the second iron stopper 36 are respectively fixed on the rotation angle circle. In the two arc-shaped grooves of the disc 5, in the radial direction, the first travel switch 6 and the second travel switch 37 are installed on both sides of the rotation angle disc 5. A first seal 10 is used to seal between the transmission shaft 9 and the first box hole 11 of the airtight box 8 . One end of the transmission shaft 9 extends into the airtight box 8, and the shaft end of the extension end of the transmission shaft 9 is fixedly connected to the input end of the cross shaft universal joint 13, and the output end of the cross shaft type universal joint 13 is connected to the test There is a detachable connection between the sample shafts 18. The detachable connection here refers to that after the two connected parts are connected together, the two are fixed to each other without any relative movement. When needed, the two connected parts can be connected together. Take apart and separate. Cooperating with the sample axis 18 are the upper sample 17 and the lower sample 21, the material, size and manufacturing process of the upper sample 17 and the lower sample 21 are exactly the same, and the upper and lower sides of both are concentric with the sample axis 18 The inner circular arc shape, the inner material is fiber braided composite material, the outer material is stainless steel (other metal materials can also be selected), and the fiber braided composite material is bonded to the inner wall of the outer material with resin. Holes are machined in the middle of the sides of the upper sample 17 and the lower sample 21, and the upper sample temperature sensor 23 and the lower sample temperature sensor 22 are installed respectively. The upper sample 17 and the lower sample 21 are installed and fixed in the arc-shaped grooves of the upper sample holder 16 and the lower sample holder 19 respectively. The lower sample clamp 19 is fixed on the support base 20, and the support base 20 is fixed on the bottom wall of the box body. The upper sample holder 16 and the dowel 15 are detachably connected. The dowel 15 is radially supported by the second bearing group 25 and extends out of the upper part of the airtight box 8 through the second box hole 26. The dowel 15 and The second box hole 26 of the airtight box 8 is sealed with a second sealing member 24 . The extended end of the dowel rod 15 is fixedly connected with the lower shaft end of the heat insulating shaft 27, and the upper shaft end of the heat insulating shaft 27 is in contact with the force measuring end of the pressure sensor 29, and the pressure sensor 29 is fixedly connected with the piston of the loading hydraulic cylinder 30. The displacement measuring rod 35 is fixedly connected to the right side of the extended end of the dowel rod 15, and the measuring head of the displacement sensor 28 is in contact with the displacement measuring rod 35. In the airtight box 8, a high-temperature heater 31, a low-temperature refrigerator 32, and an environment box temperature sensor 33 are installed.

When loading, feed high-pressure oil into the loading hydraulic cylinder 30, and the piston of the loading hydraulic cylinder 30 passes through the pressure sensor 29, heat insulation shaft 27, dowel 15, upper sample clamp 16, upper sample 17, sample shaft 18, lower The sample 21, the lower sample clamp 19, and the support seat 20 finally transmit the load to the bottom wall of the closed box 8, thereby realizing the connection between the upper sample 17 and the sample shaft 18, and the connection between the sample shaft 18 and the lower sample 21. between loads. the

The servo motor 1 starts, and through the first shaft coupling 2, the torque meter 3, and the second shaft coupling 4, the safety shaft 14 and the rotation angle disc 5 fixedly connected to the safety shaft 14 are driven to rotate counterclockwise. When the first stopper 34 on the disk 5 is in contact with the first travel switch 6, the servo motor 1 is rotated in the opposite direction through the control system, that is, clockwise. When the servo motor 1 passes through the first coupling 2 and the torque meter 3 1. The second shaft coupling 4 drives the safety shaft 14 and the rotation angle disc 5 fixedly connected to the safety shaft 14 to rotate clockwise. When the second stop iron 36 on the rotation angle disc 5 contacts with the travel switch 37, The servo motor 1 is rotated counterclockwise by the control system, and clockwise and counterclockwise mentioned here are viewed from the side of the servo motor 1 to the direction of the rotation angle disc 5 . The swing frequency of the sample shaft 18 can be adjusted by adjusting the rotational speed of the servo motor through the control system, and the swing frequency and swing angle adjustment of the sample shaft 18 can be realized by adjusting the positions of the first iron stopper 34 and the second iron stopper 36 of the rotation angle disc 5 , to realize the motion mode simulation for the tribological performance evaluation of polymer composites.

When the upper sample 17 and the sample shaft 18 wear and tear, the upper sample 17, the upper sample clamp 16, and the dowel 15 will have a downward displacement, which will be transmitted to the displacement sensor 28 through the displacement measuring rod 35. When the test When wear occurs between the sample shaft 18 and the lower sample 21, the sample shaft 18, the upper sample 17, the upper sample clamp 16, and the dowel 15 will generate a downward displacement, which will be transmitted to the displacement through the displacement measuring rod 35. The wear amount data detected by the sensor 28 , that is, the displacement sensor 28 is the sum of the wear amount of the upper sample 17 and the sample shaft 18 , and the wear amount of the sample shaft 18 and the lower sample 21 . When the wear between the sample shaft 18 and the lower sample 21 results in a downward displacement of the sample shaft 18, since the sample shaft 18 and the rotary shaft 9 are connected by a cross shaft universal joint 13, The specimen axis 18 remains horizontal under the clamping constraints of the upper specimen 17 and the lower specimen 21 .

Before the experiment, the friction torque limit value is set through the control system. When the upper sample 17 or the lower sample 21 is severely worn and the friction torque exceeds the set friction torque limit value, the experimental machine stops running. When the torque between the upper sample 17 and the sample shaft 18, or between the sample shaft 18 and the lower sample 21 suddenly increases and exceeds the detection range of the torque meter, the safety shaft will be cut off, which can protect the torque instrument function.

When it is necessary to simulate the ambient temperature, when the temperature is high, the target temperature is set by the control system, and the high temperature heater 31 is operated. When the environmental box temperature sensor 33 detects that the ambient temperature reaches the target temperature, the high temperature heater 31 stops running. When the temperature is low, the target temperature is set by the control device, and the low-temperature refrigerator 32 is operated. When the environmental box temperature sensor 33 detects that the ambient temperature reaches the target temperature, the low-temperature refrigerator 32 stops running.

Claims (4)

1. A testing machine for evaluating the tribological performance of polymer composite materials, comprising a closed box, characterized in that: a transmission shaft is supported on the box wall by a bearing group, and the transmission shaft extends out of the box The shaft end at one end is connected to the output end of the safety shaft through a coupling, the input end of the safety shaft is connected to the output shaft of the torque meter through a coupling, and the input shaft of the torque meter is connected to the output shaft of the servo motor through a coupling , a rotation angle disk is installed on the safety shaft, and two circular arc grooves are symmetrically opened on the disk surface of the rotation angle disk, and a first iron stopper and a second iron stopper are respectively arranged in the two arc grooves. In the radial direction, the first travel switch and the second travel switch are installed on both sides of the rotation angle disc; the shaft end of the drive shaft extending into the box is connected to the sample shaft through a universal cross coupling. An upper sample fixture and a lower sample fixture are arranged around the sample axis. The upper sample fixture is connected with a dowel bar, one end of the dowel bar extends out of the box, and there is a bearing group between the dowel bar and the box wall. The end of the dowel rod protruding from the box is installed with a heat-insulating shaft, which is in contact with the force-measuring end of a pressure sensor. The pressure sensor is fixedly connected to a hydraulic cylinder piston. The displacement measuring rod is in contact with the displacement sensor. 2. The testing machine for evaluating the tribological properties of polymer composite materials according to claim 1, wherein the axes of the transmission shaft and the dowel rod are located in the same plane and are perpendicular to each other. 3. The experimental machine for evaluating the tribological properties of polymer composite materials according to claim 1, characterized in that: there is a seal between the transmission shaft and the wall of the closed box, and there is a seal between the dowel rod and the wall of the closed box. There is a seal between them. 4. The experimental machine for evaluating the tribological properties of polymer composite materials according to claim 1, characterized in that: a high-temperature heater, a low-temperature refrigerator and an environmental box temperature sensor are arranged in the box.

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