An adaptive parallel fixture and method suitable for bushing-disk testing

Abstract

The application discloses a self-adaptive parallel clamp and method suitable for bushing-disk test and belongs to the technical field of mechanical engineering, which comprises a supporting mechanism, a parallelism adjusting mechanism is arranged in the supporting mechanism, the lower end of the supporting mechanism is connected with a clamping rod, a sample clamping mechanism is arranged at the lower end of the clamping rod, and a motion mechanism is arranged at the lower end of the sample clamping mechanism. The self-adaptive parallel clamp is used to solve the parallelism error problem between the bushing and the disk, so that the horizontal load error and the measurement error of the friction force and the friction coefficient caused by the error are reduced, and more accurate face-face friction and wear disk test experiments are realized.

Description

Technical Field

[0001] This invention belongs to the field of mechanical engineering technology, specifically relating to an adaptive parallel fixture suitable for bushing-disc testing. Background Technology

[0002] The high-pressure compressor is one of the core components of an aero-engine, and its variable stator vane adjustment mechanism (VSV) contains multiple adjustment mechanisms composed of shafts, bushings, and other components. These mechanisms operate in harsh environments with high temperatures and variable gas loads. Therefore, researching reinforced metallic coatings with high-temperature wear resistance is particularly important. Such coatings are typically applied to the end faces and inner surfaces of bushings to enhance their wear resistance and service life.

[0003] To test the high-temperature tribological properties of the reinforced metal coating on the bushing end face, a bushing-disc test is required. This test requires relative contact movement between the bushing end face and the disk sample, but unlike the traditional ball-disc test, the face-to-face disk test has high requirements for the parallelism of the end faces of the two.

[0004] While existing technologies offer some solutions, they also have limitations. Patent application CN202010152813.8 discloses a bearing current-carrying friction testing device and method. However, it achieves face-to-face contact through an arc-shaped carbon plate, relying on the plate's ductility, and cannot handle large loads. Patent application CN202411988935.5 discloses a high-temperature, high-pressure fluid-lubricated rotating plane friction and wear testing device. It adds a spherical universal joint to the lower sample to ensure automatic contact, but it doesn't fix the lower sample after automatic contact; only the upper sample is fixed with a locking nut. This causes the lower end face to still experience slight left-right swaying due to wear during loading, and the degree of freedom of the single spherical universal joint cannot guarantee perfect face-to-face parallelism.

[0005] Therefore, a new solution is urgently needed. Summary of the Invention

[0006] The purpose of this invention is to provide an adaptive parallel fixture and method suitable for bushing-disc testing, which solves the problem of parallelism error between the bushing and the disc, thereby reducing the horizontal load error and the measurement error of friction force and friction coefficient caused by this error, and realizing a more accurate test of surface-to-surface friction and wear disc.

[0007] To achieve the above objectives, the present invention provides an adaptive parallel fixture suitable for bushing-disc testing, comprising a support mechanism, wherein a parallelism adjustment mechanism is provided inside the support mechanism, the lower end of the support mechanism is connected to a clamping rod, the lower end of the clamping rod is provided with a sample clamping mechanism, and the lower end of the sample clamping mechanism is provided with a motion mechanism.

[0008] Preferably, the support mechanism includes a ball joint upper flange, the lower end of which is connected to the top of the connecting column, the ball joint upper flange moves axially along the connecting column, and a spring is provided on the outside of the connecting column.

[0009] Preferably, the lower end of the connecting column is fixedly connected to the lower flange of the ball joint, and the connection part between the lower flange of the ball joint and the connecting column is provided with a threaded hole.

[0010] Preferably, the parallelism adjustment mechanism includes an upper ball joint, the upper end of which is connected to the upper flange of the ball joint, the lower end of which is connected to the upper end of the lower ball joint, and the lower end of which is connected to the lower flange of the ball joint.

[0011] Preferably, a locking structure is provided below the lower flange of the ball joint. The locking structure is connected to the clamping rod. The inner diameter of the locking structure is larger than the outer diameter of the clamping rod. The clamping rod passes through the locking structure and is sequentially connected to the lower ball joint and the upper ball joint.

[0012] Preferably, the sample clamping mechanism includes a clamp housing, the outer side of which is provided with a first threaded hole, and the inner side of which is provided with a second threaded hole.

[0013] Preferably, the fixture outer shell is provided with a fixture inner shell, and the fixture inner shell is fixed to the fixture outer shell by bolts.

[0014] Preferably, a bushing is provided between the outer shell of the clamp and the inner shell of the clamp, the end face of the bushing is horizontal and located below the inner shell of the clamp.

[0015] Preferably, the motion mechanism includes a disc sample, the lower end of which is connected to a disc, and the lower end of which is connected to a lower flange of the disc.

[0016] Preferably, the lower end of the under-panel flange is connected to the output shaft of the servo motor.

[0017] The present invention also provides a method for using an adaptive parallel fixture suitable for bushing-disc tests, comprising the following steps:

[0018] Step S1: First, place the bushing inside the fixture housing with the bushing end face facing down. Then, insert the fixture inner housing into the bushing inner hole and screw in the internal hexagonal screw through the first threaded hole on the outside of the fixture housing to fix the fixture inner housing and the fixture housing to the specified torque. Then, screw in the internal hexagonal set screw through the second threaded hole in the center of the fixture housing to further lock the fixture inner housing, ensuring that the bushing end face is horizontal and exposed below the fixture inner housing. Finally, tighten and fix the assembled bushing fixture to the lower end of the clamping rod to form the sample clamping mechanism.

[0019] Step S2: Pass the sample clamping mechanism (including clamping rod 4) through the locking structure, use the inner hole of the locking structure to constrain the horizontal movement of the clamping rod, and connect the upper end of the clamping rod to the lower ball joint to ensure a stable connection.

[0020] Step S3: The support mechanism (including the upper flange of the ball joint, spring, connecting column, lower flange of the ball joint, etc.) is controlled by the motor to apply downward pressure, so that the end face of the bushing slowly descends and slightly contacts the surface of the disk sample; by using the double ball joint mechanism composed of the upper and lower ball joints inside the support mechanism, the end faces of the bushing and the disk sample are gradually made to reach a parallel state through multi-dimensional degree of freedom adjustment.

[0021] Step S4: After the bushing is completely parallel to the end face of the disc sample, tighten the locking structure and clamping rod with bolts to completely constrain the horizontal degree of freedom of the sample clamping mechanism and ensure that the parallelism remains unchanged during the test. Start the servo motor to drive the disc sample to perform relative friction and wear motion with the bushing according to preset parameters (such as speed and load), and record the test data such as friction force, friction coefficient, and wear amount at the same time.

[0022] Therefore, the present invention employs the above-mentioned adaptive parallel fixture and method suitable for bushing-disc tests, and compared with the prior art, the present invention has the following significant advantages:

[0023] (1) This invention achieves adaptive surface-to-surface parallel alignment through a double ball joint structure and is fixed by a locking structure. This effectively solves the problem of horizontal force variation caused by low end-face parallelism, thereby reducing the error in measuring friction force and friction coefficient;

[0024] (2) The present invention fixes the clamping rod by locking structure, which ensures that the two sample pieces maintain constant parallelism during loading, avoids slight swaying caused by wear, and thus ensures the stability of the experiment and the reliability of the results.

[0025] (3) The present invention fully locks the bushing with multiple internal hex bolts, so that the end face of the bushing is completely horizontal and located on the outermost side. This not only improves the stability of clamping, but also facilitates high-precision friction and wear tests, which helps to obtain more accurate data.

[0026] (4) The present invention allows spring compression during loading, providing a flexible vertical loading mechanism while ensuring the stability of the entire system;

[0027] (5) This invention is applicable to the high-temperature friction and wear performance testing of the reinforced metal coating on the bushing end face in the adjustable stator vane adjustment mechanism (VSV) of a high-pressure compressor. Its precise parallel adjustment function and stable clamping method are of great significance for studying the wear resistance of materials under high-temperature environments.

[0028] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of an adaptive parallel fixture suitable for bushing-disc testing according to the present invention;

[0030] Figure 2 This is a schematic diagram of the bushing fixture structure of an adaptive parallel fixture suitable for bushing-disc testing according to the present invention.

[0031] Figure Labels

[0032] 1. Spring; 2. Lower flange of ball joint; 3. Locking structure; 4. Clamping rod; 5. Bushing fixture; 501. Fixture housing; 502. Fixture inner housing; 503. First threaded hole; 504. Second threaded hole; 6. Disc; 7. Disc sample; 8. Lower flange of disc; 9. Bushing; 10. Servo motor; 11. Lower ball joint; 12. Upper ball joint; 13. Connecting column; 14. Upper flange of ball joint. Detailed Implementation

[0033] 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, not all embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used in the present invention should have the ordinary meaning understood by those skilled in the art.

[0034] Example 1

[0035] like Figures 1-2 As shown, an adaptive parallel fixture for bushing-disc testing according to the present invention includes an upper ball joint flange 14, a spring 1 wrapped around the outside of a connecting column 13, the top of the spring 1 connected to the upper ball joint flange 14, the bottom of the spring 1 connected to a lower ball joint flange 2, and the lower ball joint flange 2 connected to the bottom of the connecting column 13. A threaded hole is provided at the connection between the lower ball joint flange 2 and the connecting column 13. The lower ball joint flange 2 is fixedly connected to the connecting column 13 for positioning and supporting the connecting column 13. The connecting column 13 extends through the entire device, supporting the connection between the upper and lower components.

[0036] Spring 1 is located on the outside of connecting column 13. A hole is provided at the lower end of the upper ball joint flange 14 where it connects to the connecting column 13. The upper ball joint flange 14 moves axially along the connecting column 13 through the hole to accommodate parallelism adjustments between different sample pieces. The lower ball joint flange 2 is a solid recess connected to the connecting column 13. The arrangement of spring 1 around the connecting column 13 allows for cushioning and pressure adjustment during loading, ensuring the stability of the entire device. The solid recess design on the lower ball joint flange 2 provides additional support points, enhancing the overall structural stability and reliability, and preventing displacement or deformation caused by external loads.

[0037] The lower end of the upper flange 14 of the ball joint is connected to the upper end of the upper ball joint 12, and the lower end of the upper ball joint 12 is connected to the upper end of the lower ball joint 11. The upper ball joint 12 and the lower ball joint 11 are used to flexibly adjust the parallelism between the two sample pieces, ensuring that the two sample pieces can make completely parallel contact face to face. The lower end of the lower ball joint 11 is connected to the lower flange 2 of the ball joint.

[0038] The lower end of the lower flange 2 of the ball joint is connected to the locking structure 3. A clamping rod 4 is provided below the locking structure 3. The inner diameter of the locking structure 3 is slightly larger than the outer diameter of the clamping rod 4. The clamping rod 4 passes through the locking structure 3 and is connected to the lower ball joint 11 and the upper ball joint 12 in sequence. After the upper ball joint 12 and the lower ball joint 11 complete the initial alignment of the two samples, they are pressed down. Since the inner diameter of the locking structure 3 is slightly larger than the outer diameter of the clamping rod 4, the parallelism of the samples can be adjusted by changing the position of the locking structure 3. After the adjustment is completed, the clamping rod 4 is fixed to the locking structure 3 with bolts.

[0039] The lower end of the clamping rod 4 is connected to the bushing clamp 5. The bushing clamp 5 includes a clamp housing 501, and the outer side of the clamp housing 501 is provided with a first threaded hole 503 that matches a full-threaded hex socket head cap screw. A clamp inner housing 502 is provided inside the clamp housing 501. The clamp inner housing 502 is placed inside the clamp housing 501 and is fixed by a full-threaded hex socket head cap screw. The center of the clamp housing 501 is provided with a second threaded hole 504 that matches a full-threaded hex socket head cap screw. The clamp inner housing 502 and the clamp housing 501 are fixed by a full-threaded hex socket head cap screw.

[0040] During installation, first place the bushing 9 inside the fixture housing 501, then place the fixture inner housing 502 inside the bushing 9. Next, use a full-threaded hex socket head cap screw to secure the fixture inner housing 502 to the fixture housing 501. Finally, use a hex socket set screw to fix the fixture inner housing 502 and the fixture housing 501 in place, ensuring that the end face of the bushing 9 is completely horizontal and located below the fixture inner housing 502. This design securely positions the bushing 9 between the fixture housing 501 and the fixture inner housing 502.

[0041] A disc sample 7 is positioned below the bushing 9, and the disc sample 7 moves in relative contact with the bushing 9. The lower end of the disc sample 7 is mounted on the disc 6, and the lower end of the disc 6 is connected to the lower flange 8. The lower end of the lower flange 8 is connected to the output shaft of the servo motor 10. The servo motor 10 serves as a power source to provide power for the loading process.

[0042] An adaptive parallel fixture method for bushing-disc testing includes the following steps:

[0043] Step S1: First, place the bushing 9 inside the fixture housing 501 with the end face of the bushing 9 facing down; then, insert the fixture inner housing 502 into the inner hole of the bushing 9, and screw in the internal hexagon socket head cap screw through the first threaded hole 503 on the outside of the fixture housing 501 to fix the fixture inner housing 502 and the fixture housing 501 with the specified torque; then, screw in the internal hexagon socket head cap set screw through the second threaded hole 504 in the center of the fixture housing 501 to further lock the fixture inner housing 502, ensuring that the end face of the bushing 9 is horizontal and exposed below the fixture inner housing 502; finally, tighten and fix the assembled bushing fixture 5 and the lower end of the clamping rod 4 to form a sample clamping mechanism.

[0044] Step S2: Pass the sample clamping mechanism (including clamping rod 4) through the locking structure 3, and use the inner hole of the locking structure 3 to constrain the horizontal movement of the clamping rod 4; at the same time, connect the upper end of the clamping rod 4 to the lower ball joint 11 to ensure a stable connection.

[0045] Step S3: The motor controls the support mechanism (including the upper flange 14 of the ball joint, spring 1, connecting column 13, lower flange 2 of the ball joint, etc.) to apply downward pressure, so that the end face of the bushing 9 slowly descends and slightly contacts the surface of the disk sample 7; using the double ball joint mechanism composed of the upper ball joint 12 and the lower ball joint 11 inside the support mechanism, the end faces of the bushing 9 and the disk sample 7 are gradually made parallel through multi-dimensional degree of freedom adjustment.

[0046] Step S4: After the bushing 9 is completely parallel to the end face of the disc sample 7, tighten the locking structure 3 and the clamping rod 4 with bolts to completely constrain the horizontal degree of freedom of the sample clamping mechanism and ensure that the parallelism remains unchanged during the test. Start the servo motor 10 to drive the disc sample 7 to perform relative friction and wear motion with the bushing 9 according to preset parameters (such as speed and load), and record the test data such as friction force, friction coefficient, and wear amount at the same time.

[0047] Therefore, the present invention adopts the above-mentioned adaptive parallel fixture and method suitable for bushing-disc tests, which solves the problem of parallelism error between bushing and disk, thereby reducing the horizontal load error and friction force and friction coefficient measurement error caused by this error, and realizing a more accurate surface-to-surface friction wear disk test.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. An adaptive parallel fixture suitable for bushing-disc tests, characterized in that, The system includes a support mechanism, which includes an upper flange of a ball joint. The lower end of the upper flange of the ball joint is connected to the top of a connecting column. The upper flange of the ball joint moves axially along the connecting column. A spring is provided on the outside of the connecting column. The lower end of the connecting column is fixedly connected to a lower flange of the ball joint. A threaded hole is provided at the connection between the lower flange of the ball joint and the connecting column. The lower flange of the ball joint has a solid recessed structure. The support mechanism is equipped with a parallelism adjustment mechanism, which includes an upper ball joint and a lower ball joint. The upper end of the upper ball joint is connected to the upper flange of the ball joint, the lower end of the upper ball joint is connected to the upper end of the lower ball joint, and the lower end of the lower ball joint is connected to the lower flange of the ball joint. A locking structure is located below the lower flange of the ball joint. The inner diameter of the locking structure is larger than the outer diameter of the clamping rod. The locking structure is connected to the clamping rod. After passing through the locking structure, the clamping rod is sequentially connected to the lower ball joint and the upper ball joint. The lower end of the support mechanism is connected to the clamping rod. The lower end of the clamping rod is provided with a sample clamping mechanism. The sample clamping mechanism includes a clamp housing. The outer side of the clamp housing is provided with a first threaded hole. The inner side of the clamp housing is provided with a second threaded hole. The inner side of the clamp housing is provided with a clamp inner shell. A bushing is provided between the clamp housing and the clamp inner shell. The end face of the bushing is horizontally positioned and exposed below the clamp inner shell. The lower end of the sample clamping mechanism is provided with a motion mechanism, which includes a disc sample. The lower end of the disc sample is connected to the disc, the lower end of the disc is connected to the lower flange of the disc, and the lower end of the lower flange of the disc is connected to the output shaft of a servo motor.

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