A fixture for contact wire and carbon slide wear testing and a clamping method thereof

Abstract

The present invention discloses a fixture for testing the wear of contact lines and carbon slide plates, and a clamping method thereof, comprising a fixture disk having a plurality of guide grooves arranged along its circumferential array, a fixture block being slidably connected in each guide groove, a carbon slide plate sample being clamped between each fixture block and the fixture disk, a wedge block being embedded between the plurality of fixture blocks, a main shaft being installed in the fixture disk, the end of the main shaft extending into the wedge block, a gas-electric slip ring being provided at the top of the wedge block, a gas-electric slip ring stud being passed through the inside of the gas-electric slip ring, the gas-electric slip ring stud extending into the inside of the main shaft and being threadedly connected to the main shaft. After the fixture of the present invention completes clamping of the carbon slide plate, it rotates as a whole to test the high-speed rail contact line sample. The fixture block further locks the carbon slide plate under the action of centrifugal force, thereby preventing it from loosening. At the same time, the spring pins installed in the seam holes of the carbon slide plate and the spring pressure plate between the fixture block and the fixture block improve the reliability of the contact.

Description

Technical Field

[0001] The present invention relates to a wear testing device and a clamping method thereof, in particular to a fixture for wear testing of a contact line and a carbon slide plate and a clamping method thereof. Background Art

[0002] High-speed rail's catenary system is subject to the combined effects of high voltage, high current, high-speed friction, and high suspension tension, which can easily lead to abnormal wear. To develop new high-speed rail conductor materials, current-carrying testing equipment is required to test them. Existing carbon slides are all rectangular strips. Processing them into discs allows for pin-on-disc friction testing with high-speed rail conductor specimens. However, carbon slides are difficult to directly process into discs, and rectangular strip-shaped carbon slide specimens are difficult to clamp on the testing machine. Furthermore, the high currents during testing can cause high temperatures, which can affect the lifespan of sensors and equipment.

[0003] For example, patent 201920820497.X discloses a pantograph fatigue test device that can be used to test the wear of the carbon slide under certain conditions. During the test, the high-speed rail conductor sample is wound into a closed circular ring and makes ring-block contact with the carbon slide. Initially, it is point contact. As the wear increases, wear marks with shallow sides and deep middle will gradually form on the carbon slide. The conductor sample wears slowly and the test efficiency is low.

[0004] For example, patent 202111084425.1 discloses an experimental device for the friction loss between high-strength high-speed rail contact wires and pantographs, which can be used to simulate the actual working conditions of the pantograph and the contact network. However, the actual high-speed rail wires are relatively thick, with a commonly used cross-sectional area of ​​130 to 150 square millimeters, which makes it difficult to wind them into a curved shape that can be guided by a pulley set. Moreover, the experimental device mainly tests the pantograph. A certain point on the wire can only be worn once per rotation, and the wear time is long, making it impossible to perform wear tests on the wire material. Summary of the Invention

[0005] Purpose of the invention: The purpose of the present invention is to provide a fixture and a clamping method for contact wire and carbon slide wear testing, which has a simple testing process and high testing efficiency.

[0006] Technical solution: The present invention includes a fixture disk, which has multiple guide grooves along its circumferential array, and a fixture block is slidably connected in each guide groove. A carbon skateboard sample is clamped between each fixture block and the fixture disk, and wedge blocks are embedded between multiple fixture blocks. A main shaft is installed in the fixture disk, and the end of the main shaft extends into the wedge block. An air-electric slip ring is provided on the top of the wedge block, and an air-electric slip ring stud runs through the inside of the air-electric slip ring. The air-electric slip ring stud extends into the inside of the main shaft and is threadedly connected to the main shaft.

[0007] A heat sink is installed at the bottom of the fixture disk, and an air loop is provided on the surface of the heat sink. The air flow enters the threaded hole of the main shaft through the air-electric slip ring stud, flows into the air loop from the annular groove at the bottom of the threaded hole, and is finally discharged from the outlet, taking away a large amount of heat, alleviating the high heat phenomenon during the test and extending the life of the equipment and sensors.

[0008] A threaded hole is provided inside the main shaft, and the gas-electric slip ring stud is threadedly connected to the threaded hole. A ring groove is provided on the side wall of the lower part of the threaded hole, and the ring groove is communicated with the heat dissipation plate.

[0009] The main shaft passes through the heat dissipation plate and is connected to the motor, and the clamping plate is driven to rotate by the motor.

[0010] Pin holes are drilled at the seams between the carbon slide plate samples, and spring pins are installed in the pin holes.

[0011] A nut is installed at the bottom of the gas-electric slip ring, and the nut is located on the top of the wedge block and presses the wedge block.

[0012] The clamp blocks are connected to each other via springs.

[0013] A spring pressing piece is installed on the surface of the fixture block that contacts the carbon slide sample, and the fixture block contacts the carbon slide sample through the spring pressing piece.

[0014] A method for clamping a contact wire and a carbon slide wear test fixture, characterized by comprising the following steps:

[0015] Step 1: Slide the fixture blocks into the fixture plate along the guide grooves, and use springs to connect the multiple fixture blocks to each other;

[0016] Step 2: Place the carbon slide plate sample into the fixture plate, and support the wedge block between multiple fixture blocks, with the center hole of the wedge block aligned with the main shaft for positioning;

[0017] Step 3: Install the nut and the pneumatic slip ring, press the wedge block below the nut downward, and push the fixture block to move around along the guide groove to clamp the carbon slide specimen;

[0018] Step 4: Install spring pins at the joints of the carbon slide sample;

[0019] Step 5: Grind the carbon slide plate sample. After grinding, use a double-acting cylinder to clamp the high-speed rail conductor sample and rub the high-speed rail conductor sample against the carbon slide plate sample to complete the test.

[0020] Beneficial effects: The present invention only needs to cut the existing carbon skateboard into rectangular strip samples of equal length to carry out the test, and there is no need to prepare it into other shapes. The process is simplified, the testing process is simple, and the effect is high; a multi-path parallel method is adopted, and the current can be transmitted to the carbon skateboard sample through multiple paths. The multi-path parallel method can reduce the Joule heat generated by large current during the test; after the fixture completes the clamping of the carbon skateboard, it rotates as a whole to test the high-speed rail contact line sample. The fixture block will further lock the carbon skateboard under the action of centrifugal force, which plays a role in preventing loosening. At the same time, the spring pin installed in the carbon skateboard joint hole and the spring pressure plate between the fixture block improve the contact reliability, and the joints between the four carbon skateboards are filled with conductive paste, so the four carbon skateboard samples are of equal potential. When the contact line sample rubs through the gap between the two carbon skateboards, it is not easy to generate an arc due to the carbon skateboard joint; the air flow flows out from the air loop in the heat sink in turn, taking away a large amount of heat, alleviating the high heat phenomenon during the test and extending the life of the equipment and sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0022] Figure 2 yes Figure 1 sectional view of

[0023] Figure 3 It is a structural schematic diagram of the clamping plate of the present invention;

[0024] Figure 4 It is a structural schematic diagram of the heat dissipation plate of the present invention;

[0025] Figure 5 It is a structural schematic diagram of the fixture block of the present invention;

[0026] Figure 6 Schematic diagram of the experimental process of the present invention. DETAILED DESCRIPTION

[0027] The present invention will be further described below with reference to the accompanying drawings.

[0028] like Figures 1 to 6 As shown, the present invention includes a fixture plate 1 and a heat sink 8. The heat sink 8 is provided on the bottom plate of the fixture plate 1. The heat sink 8 and the fixture plate 1 are connected as a whole by multiple bolts. The main shaft 2 runs through the fixture plate 1 and the heat sink 8. Figure 3As shown, the upper surface of the fixture disk 1 is provided with a cavity. Each sidewall of the cavity is provided with a through groove extending radially outward from the fixture disk 1. The bottom of each through groove is provided with a guide groove 101 radially extending from the fixture disk 1. The guide groove 101 extends through the bottom of the fixture disk 1. A fixture block 3 is slidably connected within each guide groove 101. A carbon slide plate specimen 9 is provided between each fixture block 3 and the corresponding inner wall of the cavity. Pin holes are drilled at the seams between two adjacent carbon slide plate specimens 9. Spring pins 10 are installed in the pin holes. The installation height of the spring pins 10 must not exceed the friction plane. A wedge block 4 is embedded in the space enclosed by the four fixture blocks 3. The wedge block 4 is supported on the inclined surfaces of the four fixture blocks 3. Adjacent fixture blocks 3 are connected to each other via springs 7.

[0029] like Figure 2 As shown, the spindle 2 passes through the heat sink 8 and the fixture plate 1. The fixture plate 1 and the spindle 2 are keyed to transmit torque. The top of the spindle 2 extends from the fixture plate 1, and its end extends into the wedge block 4. The inside of the gas-electric slip ring 6 is penetrated by a gas-electric slip ring stud 601. The bottom of the gas-electric slip ring 6 is connected to a nut 5. The nut 5 extends from the bottom of the gas-electric slip ring stud 601 and connects to the threaded hole inside the spindle 2, so that the nut 5 presses the wedge block 4, and then presses the carbon slide plate specimen 9 through the fixture block 3. The hole wall at the bottom of the threaded hole is provided with an annular groove, which connects to the heat sink 8 through the annular groove for heat dissipation.

[0030] like Figure 4 As shown, a spiral air loop 801 is provided on the surface where the heat sink 8 contacts the fixture disk 1. The center of the loop is an air inlet, and the end of the loop is an air outlet, which is provided on the outer wall of the heat sink 8. The air flows into the threaded hole of the main shaft 2 from the air-electric slip ring stud 601, and flows into the air loop 801 from the annular groove at the bottom of the threaded hole, and is finally discharged from the outlet, taking away a large amount of heat, alleviating the high heat phenomenon during the test, and extending the life of the equipment and sensors.

[0031] like Figure 5 As shown, the fixture block 3 has a trapezoidal structure, with a rectangular groove on its vertical surface. A spring pressure piece 301 is fixed in place by screws in the rectangular groove. The spring pressure piece 301 contacts the carbon slide specimen 9, and its inclined surface presses against the wedge block 4. A T-shaped block is provided at the bottom of the fixture block 3, which slides within the T-shaped guide groove to install the fixture block 3 on the fixture plate 1.

[0032] Thermal conductive silicone grease is applied between the upper end surface of the heat dissipation plate 8 and the lower end surface of the fixture plate 1, electrical contact grease is applied between the inclined surface of the wedge block 4 and the inclined surface of the fixture block 3, and conductive paste is applied between the side surface of the carbon slide sample 9 and the inner wall of the fixture body 1.

[0033] like Figure 6As shown, the fixture is installed on the top of the box 11 and supported by ceramic bearings. A motor 14 is installed in the box 11. The motor 14 transmits torque to the main shaft 2 through an insulating coupling. A double-acting cylinder 12 is installed on the top of the box 11 to clamp the high-speed rail conductor sample 13. The double-acting cylinder 12 is loaded and pressed down to make the high-speed rail conductor sample 13 contact with the carbon slide plate sample 9. Before carrying out the test, the double-acting cylinder 12 is used to clamp the oilstone rod for loading and pressing, and the four carbon slide plate samples 9 are polished. Then the double-acting cylinder 12 is used to clamp the high-speed rail conductor sample 13 for testing to ensure that the contact line sample has a lower end face circular runout during the test. After the fixture completes clamping the carbon slide, it rotates as a whole to test the high-speed rail contact line sample. The fixture block 3 will further lock the carbon slide under the action of centrifugal force to prevent it from loosening. At the same time, the spring pin installed in the carbon slide joint hole and the spring pressure plate connected to the fixture block improve the contact reliability, and the joints between the four carbon slides are filled with conductive paste, so the four carbon slide samples are of the same potential. When the contact line sample rubs through the gap between the two carbon slides, it is not easy to generate an arc due to the carbon slide joint.

[0034] The fixture of the present invention adopts a multi-path parallel method, and current can be transmitted to the carbon slide plate sample through multiple paths, including: after the gas-electric slip ring stud is energized, the current flows through the gas-electric slip ring, the nut, the wedge block, the fixture block, and then flows into the carbon slide plate sample; the current flows through the gas-electric slip ring stud, the main shaft, the contact surface between the fixture disk and the carbon slide plate (including the bottom surface and the side wall) and then flows into the carbon slide plate sample; and the contact surface between two adjacent carbon slide plate samples. This multi-path parallel method can reduce the Joule heat generated by large current during the test process.

[0035] The clamping method of the present invention is:

[0036] Step 1: Slide the four clamp blocks into the clamp plate along the guide grooves, and use springs to connect the four clamp blocks to each other;

[0037] Step 2: Place the carbon slide plate sample into the fixture plate, and support the wedge block on the inclined surfaces of the four fixture blocks, with the center hole of the wedge block aligned with the main shaft for positioning;

[0038] Step 3: Install the nut and the gas-electric slip ring, tighten the nut, and press the wedge block below the nut downward, pushing the four clamp blocks to move around along the guide groove to clamp the carbon slide specimen;

[0039] Step 4: After clamping the carbon slide sample, drill joint holes at the joints of the four carbon slide samples and install spring pins inside the joint holes;

[0040] Step 5. After installation, apply thermal grease between the upper end of the heat sink and the lower end of the fixture, apply electrical contact grease between the wedge block and the fixture block, and apply conductive paste on all surfaces of the carbon slide specimen and the inner wall of the fixture.

[0041] Step 6. Use a double-acting cylinder to clamp the oilstone rod, and the double-acting cylinder is loaded and pressed down to grind the upper end surface of the carbon slide sample. After grinding, use the double-acting cylinder to clamp the high-speed rail conductor sample, and the double-acting cylinder is pressed down and loaded. The high-speed rail conductor sample and the carbon slide sample rub against each other to complete the test. During the test, the high-speed rail conductor sample remains stationary, and the fixture disk drives the carbon slider to rotate at high speed. The fixture block continues to clamp the carbon slider under the action of centrifugal force, which can prevent loosening. After the test is completed and the carbon slide sample is taken out, the fixture block will be reset under the action of the spring.

Claims

1. A fixture for contact wire and carbon slide wear testing, characterized in that: The fixture comprises a fixture plate, wherein the fixture plate has a plurality of guide grooves arranged in a circumferential array, a fixture block is slidably connected in each guide groove, a carbon slide sample is clamped between each fixture block and the fixture plate, a wedge block is embedded between the plurality of fixture blocks, a main shaft is installed in the fixture plate, the end of the main shaft extends into the wedge block, a gas-electric slip ring is provided on the top of the wedge block, a gas-electric slip ring stud is passed through the inside of the gas-electric slip ring, the gas-electric slip ring stud extends into the inside of the main shaft and is threadedly connected to the main shaft; A nut is installed at the bottom of the gas-electric slip ring, and the nut is located on the top of the wedge block and presses the wedge block; The fixture adopts a multi-path parallel connection method, and the current is transmitted to the carbon slide sample through multiple paths, including: after the gas-electric slip ring stud is energized, the current flows through the gas-electric slip ring, nut, wedge block, fixture block and then flows into the carbon slide sample; The current flows through the contact surface between the gas-electric slip ring stud, the main shaft, the fixture plate and the carbon slide plate, and then flows into the carbon slide plate sample; and the contact surface between two adjacent carbon slide plate samples.

2. A fixture for contact wire and carbon slide wear testing according to claim 1, characterized in that: A heat dissipation plate is installed at the bottom of the fixture plate, and an air loop is provided on the surface of the heat dissipation plate.

3. A fixture for contact wire and carbon slide wear testing according to claim 2, characterized in that: A threaded hole is provided inside the main shaft, and the gas-electric slip ring stud is threadedly connected to the threaded hole. A ring groove is provided on the side wall of the lower part of the threaded hole, and the ring groove is communicated with the heat dissipation plate.

4. A fixture for contact wire and carbon slide wear testing according to claim 3, characterized in that: The main shaft passes through the heat dissipation plate and is connected to the motor.

5. The fixture for contact wire and carbon slide wear test according to claim 1, characterized in that: Pin holes are drilled at the seams between the carbon slide plate samples, and spring pins are installed in the pin holes.

6. The fixture for contact wire and carbon slide wear test according to claim 1, characterized in that: The clamp blocks are connected to each other via springs.

7. A fixture for contact wire and carbon slide wear testing according to claim 1 or 6, characterized in that: A spring pressing piece is installed on the surface of the fixture block that contacts the carbon slide plate sample.

8. A clamping method for a contact wire and carbon slide wear test fixture according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: Slide the fixture blocks into the fixture plate along the guide grooves, and use springs to connect the multiple fixture blocks to each other; Step 2: Place the carbon slide plate sample into the fixture plate, and support the wedge block between multiple fixture blocks, with the center hole of the wedge block aligned with the main shaft for positioning; Step 3: Install the nut and the pneumatic slip ring, press the wedge block below the nut downward, and push the fixture block to move around along the guide groove to clamp the carbon slide specimen; Step 4: Install spring pins at the joints of the carbon slide sample; Step 5: Grind the carbon slide plate sample. After grinding, use a double-acting cylinder to clamp the high-speed rail conductor sample and rub the high-speed rail conductor sample against the carbon slide plate sample to complete the test.

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