A rack gear test device and method for rack train with adjustable center distance

Abstract

This invention belongs to the field of rail transit testing technology and discloses a gear-rail meshing test device and method for rack trains with adjustable center distance. The device includes a test rack fixed to a base surface and two guide rails located on both sides of the test rack. A mounting frame is provided above the test rack, slidingly engaging with the guide rails. A test gear and a drive device connected to the test gear are rotatably mounted on the mounting frame. The test gear passes through the mounting frame and meshes with the test rack. An adjustment structure is provided between the mounting frame and the test gear to adjust the center distance between the test rack and the test gear. This invention can more accurately simulate the change in the center distance of gear-rail meshing during rack train operation, thereby verifying the actual meshing performance within the range of center distance variation and obtaining more accurate and effective test data.

Description

Technical Field

[0001] This invention belongs to the field of rail transit testing technology, specifically relating to a gear and rail meshing test device and method for gear trains with adjustable center distance. Background Technology

[0002] A cogwheel train is a new type of rail transit vehicle used in mountain railways, particularly suitable for sightseeing routes in mountainous areas or tourist attractions. The cogwheel train uses a combination of racks and wheels, with gears on the bogies meshing with the racks, giving the train tremendous climbing ability.

[0003] Because the gear assembly meshing with the rack and rail is mounted on the bogie of the rack and rail train, friction between the train wheels and rails causes wheel wear. This passively reduces the center distance of the gear-rail meshing transmission, affecting the meshing state of the gear and rail, and indirectly impacting the smoothness of the rack and rail train's operation. In severe cases, gear jamming may occur, rendering the train unable to run. Therefore, it is necessary to conduct gear-rail meshing performance tests to study the meshing state of the gear and rail under different center distances, verify the design scheme, and provide accurate design basis for the effective iteration of the design scheme. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a gear tooth-rail meshing test device with adjustable center distance for gear trains, which can perform meshing performance tests of gears with different center distances.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A gear-rail meshing test device for a gear train with adjustable center distance includes a test gear rail fixed to a base surface and two guide rails located on both sides of the test gear rail. A mounting frame is provided above the test gear rail and slides with the guide rails. A test gear and a drive device connected to the test gear are rotatably mounted on the mounting frame. The test gear passes through the support frame and meshes with the test gear rail.

[0007] An adjustment structure for adjusting the center distance between the test gear and the test rack is provided between the mounting frame and the test gear.

[0008] In one possible implementation, the test gear is fixedly connected to a rotating shaft, and both ends of the rotating shaft are rotatably connected to bearing mounting brackets and connected to the mounting bracket body through the bearing mounting brackets;

[0009] The adjustment structure includes an adjustment bolt and a set of first tension adjustment components that connect the bearing mounting bracket to the mounting bracket body. The adjustment bolt is threaded into a first mounting hole at the bottom of the bearing mounting bracket and its bottom end protrudes from the first mounting hole and abuts against the top of the mounting bracket body. The first tension adjustment components are parallel to the axis of the adjustment bolt, so that when the first tension adjustment components allow the bearing mounting bracket and the mounting bracket body to move relative to each other, the bearing mounting bracket and the mounting bracket body can be moved relative to each other along the axis of the adjustment bolt by rotating the adjustment bolt.

[0010] In a possible implementation, the adjustment structure further includes at least two support pads of different thicknesses, which are used to insert between the bearing mounting bracket and the mounting bracket body.

[0011] In one possible implementation, the first tension adjustment component is a first bolt fastener.

[0012] In one possible implementation, the bearing mounting base is provided with a lifting ring for connecting a lifting device.

[0013] In one possible implementation, the two sides of the test toothed rail are respectively connected to the base surface by a plurality of fixing fasteners distributed along the length direction;

[0014] The fixing fastener includes an L-shaped connector, which has a vertical connecting part and a horizontal connecting part. The vertical connecting part is connected to the side of the test gear rail by a second bolt fastener, and the horizontal connecting part is connected to the base surface by a third bolt fastener.

[0015] In a possible implementation, the third bolt fastener includes a shank with a bolt head, a nut, and at least one adjusting washer. The shank has an unthreaded section and a threaded section along its axial direction, and the diameter of the unthreaded section is smaller than the diameter of the threaded section.

[0016] The threaded section of the rod passes sequentially through the adjusting washer, the transverse connecting part of the L-shaped connector, and is connected to the nut, so as to adjust and change the meshing angle between the test gear and the test toothed rail by adjusting the adjusting washer.

[0017] In a possible implementation, multiple test toothed rails are provided along their length, and two adjacent test toothed rails are simultaneously connected by the vertical connecting part of the fixing fastener.

[0018] In one possible implementation, the mounting frame includes two support frames that are slidably engaged with one of the guide rails, the two supports are spaced apart and located on both sides of the test toothed rail, and the two ends of the two support frames are connected as one unit by a support beam.

[0019] On the other hand, a method for testing the meshing performance of gears and rails in a rack train is also provided, comprising a rack train gear meshing test device with an adjustable center distance based on any of the above technical solutions, including the following steps:

[0020] Step S1: Loosen the first bolt fastener so that the support frame and the bearing mounting frame can move vertically relative to each other;

[0021] Step S2: Connect the lifting ring on the bearing mounting bracket to the lifting device to raise the bearing mounting bracket, which is integrated with the test gear, to a lifting height;

[0022] Step S3: Screw in or out the adjusting bolt to the predetermined test position, which corresponds to the test gear position with the required test center distance. Place a support pad of the corresponding thickness between the bearing mounting bracket and the support bracket. Then, release the lifting device and tighten the first bolt fastener.

[0023] Step S4: Start the drive motor and make it rotate forward to drive the test gear to rotate, so that the test gear meshes with the tooth surface of the test tooth rail and moves forward along the test tooth rail. Collect the meshing backlash data during the meshing process until the end of the laid tooth rail is reached, stop the machine, then start the drive motor and make it rotate in reverse to perform the reciprocating test until one center distance test is completed.

[0024] Step S5: Repeat the above process when conducting tests with different center distances to verify the meshing performance of gears with different center distances.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The adjustable center distance gear-rail meshing test device of the present invention, through the symmetrical arrangement of the structure, makes the support method of the test gear and the relative position of the test gear and the test rail match the actual operation of the gear train, thereby obtaining more accurate and effective test data.

[0027] 2. The adjustable center distance gear-rail train meshing test device of the present invention can more accurately simulate the change of the center distance of gear-rail meshing during the operation of a gear train by controlling the adjusting bolt, thereby verifying the actual meshing performance within the range of center distance variation.

[0028] 3. The adjustable center distance gear tooth rail meshing test device of the present invention can verify the actual meshing performance of gear tooth rail under composite test conditions with different center distances, different tooth rail pitches, and different inclination angles by changing the installation spacing and angle of the test tooth rail.

[0029] 4. The test method for the meshing performance of gears and rails in a rack train of the present invention can verify the actual meshing performance of gears and rails under composite test conditions with different center distances, different rail pitches, and different inclination angles through a rack train gear and rail meshing test device. Attached Figure Description

[0030] Figure 1 This is a three-dimensional schematic diagram of a gear and tooth rail meshing test device for a gear train with adjustable center distance according to an embodiment of this application.

[0031] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0032] Figure 3 This is a top view of a gear and rail meshing test device for a rack train with adjustable center distance, according to an embodiment of this application.

[0033] Figure 4 for Figure 3 A cross-sectional view of section AA in the middle.

[0034] In the diagram: 1-Test gear rail; 2-Fixing fastener; 3-Guide rail; 4-Guide rail auxiliary slide; 5-Support frame; 6-Bearing mounting bracket; 7-Bearing seat cover; 8-Bearing end cover; 9-Adjusting bolt; 10-Rolling bearing; 11-Shaft; 12-Positioning wheel core; 13-Test gear; 14-Fixing pin; 15-Fixing side plate; 17-Large sprocket; 18-Positioning sleeve; 19-Small sprocket; 20-Support beam; 21-Chain; 22-Drive motor; 23-Lifting screw; 24-Support pad; 25-Adjusting washer. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0036] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0037] Please refer to Figure 1-4As shown, an embodiment of this application provides a gear meshing test device for a gear train with adjustable center distance, including a test gear 1 fixed to a base surface and two guide rails 3 located on both sides of the test gear 1. A mounting frame is provided above the test gear, which slides with the guide rails 3. A test gear 13 and a drive device connected to the test gear 13 are rotatably mounted on the mounting frame. The test gear 13 passes through a support frame 5 and meshes with the test gear 1. An adjustment structure for adjusting the center distance between the test gear 1 and the test gear 13 is provided between the mounting frame and the test gear 13.

[0038] Because the mounting frame is slidably mounted on two slide rails, the test gear 13 mounted on the mounting frame and the drive device can move as a whole. Driven by the drive device, the test gear 13 can advance along the test gear rail 1. The mounting frame provides support, and by setting an adjustment structure between it and the test gear 13, the center distance between the test gear 13 and the test gear rail 1 can be changed. This allows for corresponding meshing performance tests under different center distances, thus verifying the meshing performance of the gear and gear rail. Moreover, the symmetrical arrangement of the structure ensures that the support method of the test gear 13 and the relative position of the test gear 13 and the test gear rail 1 match the actual operation of the gear train, thereby obtaining more accurate and effective test data.

[0039] In one embodiment, the test gear 13 is fixedly connected to a rotating shaft 11, and the two ends of the rotating shaft 11 are respectively rotatably connected to bearing mounting brackets 6 and connected to the mounting bracket body through the bearing mounting brackets 6.

[0040] The test gear 13 is fixedly mounted on the rotating shaft 11, and the two ends of the rotating shaft 11 are connected to the bearing mounting brackets 6. Therefore, the test gear 13 can rotate on the bearing mounting brackets 6. Thus, under the drive of a drive device such as a drive motor 22, the rotating shaft 11 can be rotated through the chain 21. At the same time as the rotating shaft 11 rotates, the test gear 13 can also rotate synchronously, thereby realizing the drive of the test gear 13.

[0041] In a preferred embodiment of the adjustment structure, the adjustment structure includes an adjustment bolt 9 and a set of first tension adjustment components connecting the bearing mounting bracket 6 to the mounting bracket body. The adjustment bolt 9 is threaded into a first mounting hole at the bottom of the bearing mounting bracket 6 and its bottom end protrudes from the first mounting hole and abuts against the top of the mounting bracket body. The first tension adjustment components are parallel to the axial direction of the adjustment bolt 9, so that when the first tension adjustment components allow the bearing mounting bracket 6 and the mounting bracket body to move relative to each other, the bearing mounting bracket 6 and the mounting bracket body can be moved relative to each other along the axial direction of the adjustment bolt 9 by rotating the adjustment bolt 9.

[0042] The adjusting bolt 9 passes through the first mounting hole at the bottom of the bearing mounting seat, i.e., its base plate, with its bottom end abutting against the top of the mounting frame. This allows the bearing mounting seat, in a loose and movable state, to move relative to the mounting frame, thereby increasing the distance between them. The test gear 13 is mounted on the bearing mounting bracket 6, further increasing the distance between the test gear 13 and the test gear rail 1. This increased distance alters the center distance, enabling tests with different center distances. The first tension adjustment component allows the bearing mounting bracket 6 to be tightened or loosened from the mounting frame. In the loosened state, the mounting bracket and mounting frame can move relative to each other. This adjustment structure makes adjustment more convenient, and its design is simple and reasonable.

[0043] Furthermore, to improve the structural stability of the bearing mounting bracket 6 and the mounting frame body after adjustment by the adjusting bolt 9, the adjustment structure also includes at least two support pads 24 of different thicknesses. The support pads 24 are used to insert between the bearing mounting bracket 6 and the mounting frame body. Multiple support pads 24 of varying thicknesses are provided, allowing for the selection of a suitable support pad 24 based on the adjusted distance between the bearing mounting bracket 6 and the mounting frame body, thus ensuring a more stable and reliable adjusted device structure.

[0044] Specifically, the first tension adjustment component is a first bolt fastener. The first bolt fastener is a commonly used connecting component; using such a bolt fastener as the connection and adjustment component makes it more convenient, practical, and easy to replace. Of course, loosening and adjustment are achieved using the nut on it.

[0045] In another embodiment, the bearing mounting base is provided with a lifting ring for connecting a lifting device.

[0046] In this way, the components above the bearing mounting bracket 6 can be lifted by connecting the lifting ring through the lifting device, which makes it easier to initially adjust the distance between the bearing mounting bracket 6 and the mounting frame. After the initial adjustment, the center distance of the required test can be finely adjusted by adjusting the adjusting bolt 9, and the test gear 13 can be finely adjusted to the predetermined test position, which can also be the position of the bearing mounting bracket 6.

[0047] In the embodiments of this application, the two sides of the test gear 1 are respectively connected to the base surface by a plurality of fixing fasteners 2 distributed along the length direction; the fixing fastener 2 includes an L-shaped connector, the L-shaped connector having a vertical connecting part and a horizontal connecting part, the vertical connecting part being connected to the side of the test gear 1 by a second bolt fastener, and the horizontal connecting part being connected to the base surface by a third bolt fastener.

[0048] With such fasteners 2, the test gear 1 can be installed more securely on the base surface, and it is also easy to disassemble and assemble, making it more convenient and practical.

[0049] Furthermore, in order to adjust the meshing angle between the test gear 13 and the test gear rail 1, the third bolt fastener includes a rod with a bolt head, a nut, and at least one adjusting washer 25. The rod has an unthreaded section and a threaded section along its axial direction, and the diameter of the unthreaded section is smaller than the diameter of the threaded section. The threaded section of the rod passes through the adjusting washer 25, the transverse connecting part of the L-shaped connector, and is connected to the nut in sequence, so as to adjust and change the meshing angle between the test gear 13 and the test gear rail 1 by adjusting the adjusting washer 25.

[0050] In this way, the meshing angle between the test gear 13 and the test gear rail 1 can be adjusted by increasing or decreasing the number of adjusting shims 25. Since there are fixing fasteners 2 on both sides of the test gear rail 1, the meshing angle between the test gear 13 and the test gear rail 1 can be adjusted by increasing or decreasing the number of adjusting shims 25 on one or both fixing fasteners 2.

[0051] In some embodiments, multiple test toothed rails 1 are provided along their length, and two adjacent test toothed rails 1 are connected simultaneously through the vertical connecting part of the fixing fastener 2.

[0052] In this way, multiple test toothed rails 1 can be connected together by the fastener 2 to form a toothed rail of the required length, which also facilitates disassembly and assembly.

[0053] In the specific implementation process, the mounting frame includes two support frames 5, each slidably engaged with one of the guide rails 3. The two supports are spaced apart and located on both sides of the test gear rail 1. The two ends of the two support frames 5 are connected as one unit by a support beam 20. This structure makes the mounting frame more stable and simple in design.

[0054] In addition, the pitch of the toothed rail can be changed by increasing or decreasing the distance between the end faces of the two test toothed rails 1.

[0055] Embodiments of this application also provide a method for testing the meshing performance of gears and rails in a rack train, and a rack train gear meshing test device with adjustable center distance based on any of the above technical solutions, comprising the following steps:

[0056] Step S1: Loosen the first bolt fastener so that the support frame 5 and the bearing mounting frame 6 can move vertically relative to each other;

[0057] Step S2: Connect the lifting ring on the bearing mounting bracket 6 to the lifting device to raise the bearing mounting bracket 6, which is connected to the test gear 13, to a lifting height;

[0058] Step S3: Screw in or out the adjusting bolt 9 to the predetermined test position, which corresponds to the test gear 13 position with the required test center distance. Place the support pad 24 of the corresponding thickness between the bearing mounting bracket 6 and the support bracket 5. Then, release the lifting device and tighten the first bolt fastener.

[0059] Step S4: Start the drive motor 22 and make it rotate forward to drive the test gear 13 to rotate, so that the test gear 13 meshes with the tooth surface of the test tooth rail 1 and moves forward along the test tooth rail 1. Collect the meshing backlash data during the meshing process until the end of the laid tooth rail is reached, stop the machine, then start the drive motor 22 and make it rotate in reverse to perform the reciprocating test until the experiment of one center distance is completed.

[0060] Step S5: Repeat the above process when conducting tests with different center distances to verify the meshing performance of gears with different center distances.

[0061] Specifically, backlash data was collected according to the relevant provisions of the GB / Z 18620.2-2008 Inspection Implementation Specification. In gear and gear rack design, a minimum backlash at the installation center distance is specified. Backlash data collected at different center distances is compared with the specified value. If the value is greater than the specified value, normal meshing is possible; if it is less, the meshing state will be affected, and in severe cases, it may lead to tooth jamming. Therefore, the meshing performance of the gear and gear rack can be verified by collecting backlash data at different center distances.

[0062] Preferred specific embodiments:

[0063] Please refer to Figure 1-4 As shown, a gear meshing test device for a rack train with adjustable center distance mainly includes a test rack 1, a fixing fastener 2, a guide rail 3, a guide rail pair slide 4, a support frame 5, a bearing mounting frame 6, a bearing seat cover 7, a bearing end cover 8, an adjusting bolt 9, a rolling bearing 10, a rotating shaft 11, a positioning wheel core 12, a test gear 13, a fixing pin block 14, a fixing side plate 15, a positioning key, a large sprocket 17, a positioning sleeve 18, a small sprocket 19, a support beam 20, a chain 21, a drive motor 22, a lifting screw 23, a support pad 24, an adjusting washer 25, and several bolts and screws connecting fasteners.

[0064] Installation method: The test gear 1 has pre-drilled bolt holes. After placing it in the predetermined installation position, the fixing fasteners 2 are symmetrically placed on both sides of the test gear 1. Fixing fasteners 2 are also arranged at the connection points of the two test gear 1 parts. The test gear 1 and fixing fasteners 2 are fixed together by bolts. Simultaneously, the fixing fasteners 2 are fixed to the foundation by bolts, thus completing the installation of the test gear 1. The guide rails 3 are symmetrically arranged on both sides of the test gear 1. The guide rails 3 have a series of countersunk bolt holes pre-drilled according to standards. After placing the guide rails 3 in the predetermined installation position, they are fixed to the foundation by bolts. The guide rail pair slide 4 is installed according to the standard requirements of the guide rail pair.

[0065] The base plate of the support frame 5 is provided with threaded holes, which are symmetrically arranged along the left and right symmetrical planes of the bearing mounting frame 6 and the support beam 20, and symmetrically arranged along the front and rear symmetrical planes of the support frame 5. The guide rail slide 4 is provided with threaded holes corresponding to the above positions. After positioning according to the corresponding relationship, the support frame 5 is connected to the guide rail slide 4 by screws, allowing the support frame 5 to reciprocate on the guide rail 3. The support frame 5 is symmetrically arranged along both sides of the test gear rail 1. Bolt holes are also provided on the upper and lower right sides of the support frame 5 and on both sides of the support beam 20. The support beam 20 is installed between the upper and lower sides of the support frame 5 by bolts, achieving the engagement of the two support frames 5. The base plate of the bearing mounting frame 6 and the upper plate of the support frame 5 are symmetrically arranged with bolt holes along the front and rear symmetrical planes of the support frame 5. Two threaded holes for installing adjusting bolts 9 are arranged on the symmetrical planes of the front and rear bolt holes. After screwing the adjusting bolts 9 in to a certain length, the two bearing mounting frames 6 and the support frame 5 are fixed by bolts.

[0066] The positioning wheel core 12 is fitted into the front side of the rotating shaft 11, and the cylindrical surfaces of the two are press-fitted. Axial positioning is achieved by the shoulder on the rotating shaft 11. The positioning wheel core 12 and the fixed side plate 15 are each provided with 8 pin grooves on their mating sides with the test gear 13. The test gear 13 is provided with 8 corresponding pin holes. The fixed pin block 14 is installed in the pin groove on the side of the positioning wheel core 12. The test gear 13 is installed on the positioning wheel core 12 through the fixed pin block 14. The fixed side plate 15 is installed on the positioning wheel core 12, so that the pin groove on the side of the fixed side plate 15 faces the fixed pin block 14, and the contact sides of the positioning wheel core 12, the test gear 13, and the fixed side plate 15 are in close contact. Threaded holes are provided between the positioning wheel core 12 and the fixed side plate 15. The positioning wheel core 12, the test gear 13, the fixed pin block 14, and the fixed side plate 15 are fixed into a whole by screw connection.

[0067] The positioning key is installed in the keyway of the rotating shaft 11. The large sprocket 17 is mounted on the rotating shaft 11 with its side close to the shaft shoulder. The positioning sleeve 18 is close to the other side of the large sprocket 17. The large sprocket 17 is axially positioned by the shaft shoulder on the rotating shaft 11 and the positioning sleeve 18, and circumferentially positioned by the positioning key. Rolling bearings 10 are installed at both ends of the rotating shaft 11. The inner ring of the front rolling bearing 10 is close to the side of the positioning sleeve 18, and the inner ring of the rear rolling bearing 10 is close to the side of the shaft shoulder on the rotating shaft 11. The chain 21 is pre-fitted onto the large sprocket 17. This completes the installation of a series of parts, including the rolling bearing 10, rotating shaft 11, positioning wheel core 12, test gear 13, fixing pin block 14, fixing side plate 15, positioning key, large sprocket 17, positioning sleeve 18, and chain 21.

[0068] The aforementioned rotating shaft 11 and its components are mounted on two bearing mounting brackets 6 via two side rolling bearings 10. The outer ring sides of the two end rolling bearings 10 are close to the inner side of the grooves in the bearing mounting brackets 6, and the teeth on the test gear 13 fall into the tooth grooves of the test gear rail 1. The contact plate between the two side bearing seat covers 7 and the bearing mounting brackets 6 is provided with bolt holes, and six screw holes are evenly distributed on the outer side. The two are fixed by bolt connection. The flange of the bearing end cover 8 is pressed against the outer ring sides of the two end rolling bearings 10 and fixed with screws. The two side bearing seat covers 7 are provided with lifting screw holes, and two lifting screws 23 are screwed in. The plate on the support beam 20 is provided with bolt holes. The drive motor 22 is installed and fixed on the support beam 20 by bolt connection. The chain 21 is fitted onto the small sprocket 19, and the sprocket 19 is installed on the output shaft of the drive motor 22 by key connection.

[0069] During the specific test, the fastening bolts between the base plate of the bearing mounting bracket 6 and the upper plate of the support frame 5 are loosened. After the lifting screws 23 on both sides are lifted to a certain height by the hoisting device at the test site, the adjusting bolts 9 are screwed in or out to the predetermined test position. The corresponding support pads 24 are placed between the base plate of the bearing mounting bracket 6 and the upper plate of the support frame 5. The hoisting device is lowered, and after the base plate of the bearing mounting bracket 6 and the upper plate of the support frame 5 are securely fastened, the drive motor 22 is started to rotate forward, driving the test gear 13 to rotate, so that the test gear 13 meshes with the tooth surface of the test tooth rail 1 and moves forward along the test tooth rail 1. The meshing backlash data is collected during the meshing process until the end of the tooth rail is reached. The machine is stopped, and the drive motor 22 is started to rotate in reverse to realize the reciprocating test process on the tooth rail. After a certain center distance test is completed, the above process is repeated to verify the meshing performance of gears and tooth rails with different center distances.

[0070] Increase or decrease the distance between the two test gear 1 parts to change the pitch between the test gear 1 teeth; add or remove the adjusting washers 25 of the bolted connection below the single-sided fixing fastener 2 of the fixed test gear 1 to change the meshing angle between the test gear 13 and the test gear 1.

[0071] This embodiment can simulate and verify the gear and rack meshing performance of a rack train under comprehensive working conditions such as natural wear, installation error, and geological changes.

[0072] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A rack gear test device for rack and pinion trains with adjustable center distance, characterized in that: It includes a test gear rail fixed to a base surface and two guide rails located on both sides of the test gear rail. Above the test gear rail is a mounting frame that slides with the guide rails. A test gear and a drive device connected to the test gear are rotatably mounted on the mounting frame. The test gear passes through the support frame and meshes with the test gear rail. An adjustment structure for adjusting the center distance between the test gear and the test tooth track is provided between the mounting frame and the test gear. The test gear rack is connected to the base surface on both sides by multiple fixing fasteners distributed along its length. Each fixing fastener includes an L-shaped connector with a vertical connecting portion and a horizontal connecting portion. The vertical connecting portion is connected to the side of the test gear rack via a second bolt fastener, and the horizontal connecting portion is connected to the base surface via a third bolt fastener. The third bolt fastener includes a rod with a bolt head, a nut, and at least one adjusting washer. The rod has an unthreaded section and a threaded section along its axial direction, with the diameter of the unthreaded section being smaller than the diameter of the threaded section. The threaded section of the rod passes sequentially through the adjusting washer, the horizontal connecting portion of the L-shaped connector, and connects to the nut, thereby adjusting the meshing angle between the test gear and the test gear rack by adjusting the washer.

2. The rack and pinion test device of claim 1, wherein: The test gear is fixedly connected to a rotating shaft, and the two ends of the rotating shaft are respectively rotatably connected to bearing mounting brackets and connected to the mounting bracket body through the bearing mounting brackets; The adjustment structure includes an adjustment bolt and a set of first tension adjustment components that connect the bearing mounting bracket to the mounting bracket body. The adjustment bolt is threaded into a first mounting hole at the bottom of the bearing mounting bracket and its bottom end protrudes from the first mounting hole and abuts against the top of the mounting bracket body. The first tension adjustment components are parallel to the axis of the adjustment bolt, so that when the first tension adjustment components allow the bearing mounting bracket and the mounting bracket body to move relative to each other, the bearing mounting bracket and the mounting bracket body can be moved relative to each other along the axis of the adjustment bolt by rotating the adjustment bolt.

3. The rack and pinion test device of claim 2, wherein: The adjustment structure also includes at least two support pads of different thicknesses, which are used to insert between the bearing mounting bracket and the mounting bracket body.

4. The center distance adjustable rack train gear rack meshing test device according to claim 3, characterized in that: The first tension adjustment component is a first bolt fastener.

5. The rack and pinion train gear and rack meshing test device with adjustable center distance according to claim 2, characterized in that: The bearing mounting base is provided with a lifting ring for connecting a lifting device.

6. The center distance adjustable rack train gear rack meshing test device according to any one of claims 1-5, characterized in that: The test toothed rails are provided in multiple ways along their length, and two adjacent test toothed rails are connected simultaneously through the vertical connecting part of the fixing fastener.

7. The center distance adjustable rack and pinion train gear and rack meshing test device according to claim 1, characterized in that: The mounting frame includes two support frames that are slidably engaged with one of the guide rails. The two supports are spaced apart and located on both sides of the test toothed rail. The two ends of the two support frames are connected as one unit by a support beam.

8. A rack railway gear rack meshing performance test method based on the rack railway gear rack meshing test device with adjustable center distance according to any one of claims 1-7, characterized in that: Includes the following steps: Step S1: Loosen the first bolt fastener so that the support frame and the bearing mounting frame can move vertically relative to each other; Step S2: Connect the lifting ring on the bearing mounting bracket to the lifting device to raise the bearing mounting bracket, which is integrated with the test gear, to a lifting height; Step S3: Screw in or out the adjusting bolt to the predetermined test position, which corresponds to the test gear position with the required test center distance. Place a support pad of the corresponding thickness between the bearing mounting bracket and the support bracket. Then, release the lifting device and tighten the first bolt fastener. Step S4: Start the drive motor and make it rotate forward to drive the test gear to rotate, so that the test gear meshes with the tooth surface of the test tooth rail and moves forward along the test tooth rail. Collect the meshing backlash data during the meshing process until the end of the laid tooth rail is reached, stop the machine, then start the drive motor and make it rotate in reverse to perform the reciprocating test until one center distance test is completed. Step S5: Repeat the above process when conducting tests with different center distances to verify the meshing performance of gears with different center distances.

Images