Friction and wear test system and method for simulated working conditions of aviation tail nozzle kinematic pair

Abstract

The present invention provides a friction and wear test system and method for simulated working conditions of aviation tail nozzle kinematic pairs, including a motion loading module, a fixture module and a frame; the vertical loading motor driving end is connected to the fixture base, the horizontal loading electric cylinder and the vertical loading electric cylinder are connected through a lower fixture, or the horizontal loading electric cylinder and the vertical loading electric cylinder are each connected to a lower fixture; the fixture base drives the workpiece to be tested to rotate and load on the horizontal plane through the vertical loading motor, the vertical loading electric cylinder drives the workpiece to be tested to move in the vertical direction, and the horizontal loading electric cylinder drives the workpiece to be tested to move in the horizontal direction. The wear test system disclosed in the present invention breaks through the limitation of the single experimental object of the previous special friction and wear testing machine, and can realize the testing of three types of kinematic pairs involved in the triangular pull rod and cam roller test pieces, namely the rotating pair, the ball-and-socket pair and the cam pair, thereby improving the test range of the testing machine.

Description

Technical Field

[0001] The present invention relates to the technical field of wear testing devices, and in particular to a friction and wear testing system and method for a simulated working condition of a kinematic pair of an aviation tail nozzle. Background Art

[0002] The latest generation of advanced fighter aircraft require that the engine tail nozzle movement adjustment speed is greater than 30° / s for hypersonic cruise and high maneuverability. The movement adjustment mechanism is subjected to aerodynamic loads exceeding 10,000 Newtons and high temperatures of nearly 1,000 degrees Celsius for a long time. In order to avoid the degradation or even failure of the service performance of key motion parts of the movement adjustment mechanism during the design life cycle, thereby limiting the adjustment accuracy, response performance, life and reliability of the overall equipment system, and even causing major engineering disasters, it is urgent to clarify the degradation mechanism of the tribological performance of moving parts and optimize the surface interface tribological design. However, there is no high-temperature and heavy-load simulated working condition tribological test system suitable for the research of aviation tail nozzle movement adjustment mechanism at home and abroad, which cannot provide experimental support for the above research, limiting technological breakthroughs.

[0003] Among the existing friction and wear testing machines, the universal friction and wear testing machine is the most widely used. This type of testing machine can only test the friction and wear performance of the material level, with limited loading forms and simple motion forms. It is confined to a certain point, line, or surface of the material sample to perform specific reciprocating, rotational, and micro-motion motions. However, the actual motion mechanism has multiple components and kinematic pairs, a single part has multiple kinematic pairs, and is subjected to force at multiple points. In addition, the parts have tolerance matching characteristics and the friction and heat generated by mutual motion are obvious. The material-level test and analysis conditions based on the universal friction and wear testing machine are too simplified, and the results obtained are significantly different from the friction and wear conditions of the actual service conditions of the moving parts and kinematic pairs of the actual mechanism, and are only suitable for basic theoretical research and analysis.

[0004] In order to overcome the testing capability defects of general-purpose material-level friction and wear testers, special sample-level friction and wear testers are often developed in fields such as aerospace with strict operating conditions and high reliability requirements. Such testers have obvious customized characteristics and are only suitable for friction and wear tests of single specific moving parts. There is still a lack of high-temperature and heavy-load friction and wear testers for the study of typical kinematic pairs of aviation tail nozzle motion adjustment mechanisms.

[0005] In a Chinese patent document with authorization announcement number CN106198286B, a piston pin swing pair friction and wear component testing device is disclosed, which is suitable for the friction and wear test of the piston pin swing pair of an internal combustion engine. The motion loading form is determined by the mechanical structure, and the force magnitude and direction of the component to be tested cannot be flexibly adjusted.

[0006] A Chinese patent document with publication number CN112378671A discloses a friction and wear test bench and method for the moving pair of a compressor stator blade adjustment mechanism, which is suitable for friction and wear testing of the moving pair of a compressor stator blade adjustment mechanism. The moving form of the moving parts involved is swinging, and the moving pair is a rotating pair. The movement form is single and cannot be applied to the test requirements of multiple moving pairs of the aviation tail nozzle movement adjustment mechanism.

[0007] A Chinese patent document with authorization announcement number CN101509859B discloses a friction and wear test device for a pin-shaft friction pair. The device simulates the friction and wear behavior of the pin-shaft friction pair by wearing the loading ears against the power shaft and the driven shaft. However, the loading form is single and does not take into account the force characteristics of the loading ears. Therefore, the invention cannot be effectively applied to the friction and wear test research of the aviation tail nozzle motion adjustment mechanism. Summary of the invention

[0008] In view of the defects in the prior art, the object of the present invention is to provide a friction and wear testing system and method for a simulated working condition of an aviation tail nozzle kinematic pair.

[0009] According to the present invention, a friction and wear test system for a simulated working condition of a kinematic pair of an aviation tail nozzle is provided, comprising: a kinematic loading module, a fixture module and a frame; the kinematic loading module is fixedly mounted on the frame, and the fixture module is mounted on the kinematic loading module;

[0010] The motion loading module includes a horizontal loading electric cylinder, a vertical loading electric cylinder and a vertical loading motor, and the fixture module includes a fixture base and a lower fixture; the driving end of the vertical loading motor is connected to the fixture base, and the horizontal loading electric cylinder and the vertical loading electric cylinder are connected through the lower fixture, or the horizontal loading electric cylinder and the vertical loading electric cylinder are each connected to a lower fixture;

[0011] The fixture base drives the workpiece to be measured to rotate and load on a horizontal plane through a vertical loading motor, the vertical loading electric cylinder drives the workpiece to be measured to move in a vertical direction, and the horizontal loading electric cylinder drives the workpiece to be measured to move in a horizontal direction.

[0012] Preferably, the motion loading module further comprises a horizontal loading electric cylinder base, a horizontal loading electric cylinder guide rail, a horizontal loading electric cylinder frame, a counterweight, a grooved shaft wheel, a counterweight steel wire, and a counterweight slideway;

[0013] The horizontal loading electric cylinder is slidably mounted on the electric cylinder guide rail through the horizontal loading electric cylinder base, the electric cylinder guide rail is extended in the vertical direction, the electric cylinder guide rail is fixedly mounted on the frame, the grooved shaft wheel is rotatably mounted on the frame, one end of the counterweight steel wire is connected to the horizontal loading electric cylinder base, and the other end of the counterweight steel wire passes through the grooved shaft wheel and is fixedly connected to the counterweight block slidably set in the counterweight block slide groove, and the counterweight block slide groove is fixedly set on the frame.

[0014] Preferably, the weight of the counterweight block is equal to the sum of the weights of the horizontal loading electric cylinder, the horizontal loading electric cylinder base and the horizontal loading electric cylinder frame.

[0015] Preferably, the motion loading module further comprises a vertical loading electric cylinder base and a vertical loading electric cylinder guide rail;

[0016] The vertical loading electric cylinder guide rail is fixedly mounted on the frame, the vertical loading electric cylinder guide rail is extended in the horizontal direction, the vertical loading electric cylinder is mounted on the vertical loading electric cylinder guide rail through the vertical loading electric cylinder base, and moves in the horizontal direction along the vertical loading electric cylinder guide rail.

[0017] Preferably, the wear testing system further comprises a measurement and control module;

[0018] The measurement and control module collects and controls the load data and motion state of each motion loading module.

[0019] Preferably, the wear testing system further comprises a temperature control module and an electrical module;

[0020] The temperature control module adjusts the temperature of the test area, and the electrical module supplies power to other modules.

[0021] Preferably, the wear testing system comprises the following steps of testing the workpiece under test of the rotating pair: the fixture base is rotatably connected to one end of the workpiece under test, the other end of the workpiece under test is rotatably connected to the lower fixture, the lower fixture is respectively connected to the horizontal loading electric cylinder and the vertical loading electric cylinder, the vertical loading electric cylinder applies a preset load to the workpiece under test according to the measurement and control module, and the horizontal loading electric cylinder drives the workpiece under test to perform reciprocating motion, so that the workpiece under test and the fixture base and the lower fixture rotate.

[0022] Preferably, the wear test system testing method for the cam roller pair workpiece includes: the fixture base is rotatably connected to one end of the cam skeleton, the driving end of the horizontal loading electric cylinder is rotatably connected to the other end of the cam, the driving end of the vertical loading electric cylinder is rotatably connected to the roller assembly, the horizontal loading electric cylinder drives the cam skeleton to contact the roller assembly and move relative to each other, and the horizontal loading electric cylinder and the vertical loading electric cylinder jointly apply a preset load to the workpiece under test according to the measurement and control module;

[0023] The vertical loading electric cylinder is connected to the sensor and the guide rail of the measurement and control module through the fixture module, and the vertical loading electric cylinder base and the vertical loading electric cylinder guide rail are constrained by geometric conditions so that horizontal slippage does not occur.

[0024] Preferably, the testing method of the wear testing system for the ball-and-socket pair workpiece includes: the fixture base is rotatably connected to one end of the workpiece to be measured, the other end of the workpiece to be measured is connected to the vertical loading electric cylinder through the lower fixture, the lower fixture and the workpiece to be measured are rotatably connected through the ball-and-socket connection unit, the vertical loading motor drives the fixture base to rotate, and the vertical loading electric cylinder applies a load to the workpiece to be measured according to the measurement and control module.

[0025] A friction and wear test method for a simulated working condition of a kinematic pair of an aviation tail nozzle provided by the present invention comprises the following steps:

[0026] Step S1: Start the electrical module to transmit power to the motion loading module, the fixture module, the measurement and control module, and the temperature control module, input the preset working conditions into the measurement and control module, connect the workpiece to be measured to the motion loading module through the fixture module, and place the workpiece to be measured, the fixture module, and the motion loading module in the temperature control module;

[0027] Step S2: the measurement and control module sends the preset temperature control information to the temperature control module, and the temperature control module turns on the heating in the temperature control box and feeds back the temperature information to the measurement and control module in real time;

[0028] Step S3: When the temperature control module reaches the preset temperature, the measurement and control module sends a loading start signal to the motion loading module, and the motion loading module starts loading and feeds back the load information to the measurement and control module in real time;

[0029] Step S4: When the motion loading module reaches a preset load, the measurement and control module sends a motion start signal to the motion loading module, and the motion loading module starts the motion and feeds back the motion information to the measurement and control module in real time;

[0030] Step S5: After the motion loading module completes the specified number of motion loading cycles, the measurement and control module sends an unloading cooling signal to the motion loading module and the temperature control module. The motion loading module stops moving and returns to the preset position and completes unloading. The temperature control module stops heating and starts heat dissipation and cooling. When the temperature of the temperature control module drops to the preset safety temperature, the measurement and control module prompts the test to terminate.

[0031] Step S6: Remove the workpiece to be tested from the fixture module, and turn off the electrical module to power off the test system.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The wear test system disclosed in the present invention breaks through the limitation of the single experimental object of previous special friction and wear testers, and can test the three types of kinematic pairs involved in the triangular pull rod and cam roller test pieces, namely the rotating pair, the ball-and-socket pair and the cam pair, thereby improving the test range of the test machine.

[0034] 2. The motion loading module in the present invention has two degrees of freedom of motion and adopts a combined force loading method, which can realize programmable adjustment of the magnitude and direction of the plane force. The counterweight form overcomes the limitations of the previous large-load electric rod loading system with slow response and poor accuracy;

[0035] Other beneficial effects of the present invention will be explained in the specific implementation manner through the introduction of specific technical features and technical solutions. Through the introduction of these technical features and technical solutions, those skilled in the art should be able to understand the beneficial technical effects brought about by the technical features and technical solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0037] Figure 1 A top view of a triangular tie rod specimen in the present invention;

[0038] Figure 2 It is an isometric view of the cam roller sample of the present invention;

[0039] Figure 3 This is a functional structure diagram of the friction and wear test system for simulating working conditions of typical kinematic pairs of an aviation tail nozzle in the present invention;

[0040] Figure 4 This is a front view of the motion loading module of the friction and wear test system for the typical motion pair simulation working condition of the aviation tail nozzle of the present invention;

[0041] Figure 5 This is a schematic diagram of the mechanism movement of the friction and wear test system for the simulated working condition of a typical motion pair of an aviation tail nozzle of the present invention, and its motion loading module triangular pull rod friction and wear test;

[0042] Figure 6 This is a schematic diagram of the mechanism movement of the cam roller friction and wear test of the motion loading module of the typical motion pair simulation working condition friction and wear test system of the aviation tail nozzle of the present invention;

[0043] Figure 7 This is a front view of the module distribution of the friction and wear test system for the typical motion pair simulation working conditions of the aviation tail nozzle;

[0044] Figure 8 It is a schematic diagram of the support base structure in the present invention;

[0045] Fig. 9It is a schematic diagram of the structure of the replaceable clamping device in the present invention;

[0046] Fig.10 It is a structural schematic diagram of the roller cam pair wear test fixture in the present invention;

[0047] Fig.11 It is a structural schematic diagram of the lower fixture module in the roller cam pair wear test fixture of the present invention;

[0048] Fig.12 It is a structural schematic diagram of the ball pair rotating pair wear test fixture in the present invention;

[0049] Fig.13 It is a schematic diagram of the contact surface of the clamp in the present invention.

[0050] Description of reference numerals:

[0051] Typical motion pair specimen of aviation tail nozzle 1; triangular tie rod 101; ball-and-socket pair 102; pin rotation pair 103; cam frame 104; roller assembly 105; motion loading module 2; horizontal loading electric cylinder 201; loading electric cylinder base 202; horizontal loading electric cylinder guide rail 203; horizontal loading electric cylinder frame 204; counterweight block 205; grooved shaft wheel 206; counterweight steel wire 207; counterweight block slide 208; vertical loading electric cylinder 209; vertical loading electric cylinder base 210; vertical loading electric cylinder guide rail 211; fixture module 3; Clamp base 31; support seat 311; mounting hole 3110; mounting groove 3111; replaceable clamping device 312; pin 313; washer 314; hexagonal half-thread bolt 315; pull rod pin 316; pin retaining ring 317; lower clamp 32; U-shaped clamp head 321; screw 322; nut 323; bushing 324; lower clamp pin 325; lower clamp washer 326; ear plate seat 351; ball socket 352; ball socket pin 353; ball socket washer 354; ball socket pin 355; measurement and control module 4; temperature control module 5; electrical module 6; frame 7. DETAILED DESCRIPTION

[0052] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0053] The present invention discloses a friction and wear test system for simulated working conditions of aviation tail nozzle kinematic pair, which is suitable for friction and wear test of typical kinematic pair of aviation tail nozzle sample 1 typical kinematic pair, referring to Figure 1 and Figure 2As shown, it includes a triangular tie rod 101, a ball-and-socket pair 102, a pin rotation pair 103, a cam skeleton 104, and a roller assembly 105. The test system consists of a motion loading module 2, a fixture module 3, a measurement and control module 4, a temperature control module 5, an electrical module 6, and a frame 7. It can simulate the specific trajectory of a typical motion pair specimen 1 of an aviation tail nozzle, a low-frequency periodic motion form of 1Hz level, a multi-contact multi-directional combination, a large load of 10,000 Newtons, complex forces, and a high temperature condition of nearly one thousand degrees Celsius, and carry out friction and wear tests.

[0054] Specifically, refer to Figure 3 and Figure 4 As shown, the test system includes: a motion loading module 2 , a fixture module 3 and a frame; the motion loading module 2 is fixedly mounted on the frame, and the fixture module 3 is mounted on the motion loading module 2 .

[0055] The motion loading module 2 includes a horizontal loading electric cylinder 201, a vertical loading electric cylinder 209 and a vertical loading motor, and the clamp module 3 includes a clamp base 31 and a lower clamp 32; the vertical loading motor driving end is connected to the clamp base 31, and the horizontal loading electric cylinder 201 and the vertical loading electric cylinder 209 are connected through the lower clamp 32, or the horizontal loading electric cylinder 201 and the vertical loading electric cylinder 209 are each connected to the lower clamp 32.

[0056] The fixture base 31 drives the workpiece to be measured to rotate and load on the horizontal plane through the vertical loading motor, the vertical loading electric cylinder 209 drives the workpiece to be measured to move in the vertical direction, and the horizontal loading electric cylinder 201 drives the workpiece to be measured to move in the horizontal direction.

[0057] The motion loading module 2 also includes a horizontal loading electric cylinder base 202, a horizontal loading electric cylinder guide rail 203, a horizontal loading electric cylinder frame 204, a counterweight block 205, a grooved shaft wheel 206, a counterweight steel wire 207, and a counterweight block slide 208;

[0058] The horizontal loading electric cylinder 201 is slidably installed on the electric cylinder guide rail through the horizontal loading electric cylinder base 202, the electric cylinder guide rail is extended in the vertical direction, the electric cylinder guide rail is fixedly installed on the frame, the grooved shaft wheel 206 is rotatably installed on the frame, one end of the counterweight steel wire 207 is connected to the horizontal loading electric cylinder base 202, and the other end of the counterweight steel wire 207 passes through the grooved shaft wheel 206 and is fixedly connected to the counterweight block 205 slidingly set in the counterweight block slide groove 208, and the counterweight block slide groove 208 is fixedly set on the frame.

[0059] The weight of the counterweight 205 is equal to the sum of the weights of the horizontal loading electric cylinder 201, the horizontal loading electric cylinder base 202 and the horizontal loading electric cylinder frame 204. The steel wire 207 passes through the grooved shaft wheel 206 fixed on the frame 7, one end of which is connected to the horizontal loading electric cylinder frame 204 where the horizontal loading electric cylinder 201 is fixed, and the other end is connected to the counterweight 205. The counterweight slide 208 is fixed on the frame 7 to limit the counterweight 205 to move only in the vertical direction relative to the frame 7. The connection point between the steel wire 207 and the horizontal loading electric cylinder frame 204 is located in the vertical direction where the center of mass of the horizontal loading electric cylinder 201, the horizontal loading electric cylinder base 202 and the horizontal loading electric cylinder frame 204 is located. The mass of the counterweight 205 is equal to the horizontal loading electric cylinder 201. The sum of the masses of the horizontal loading electric cylinder 201, the horizontal loading electric cylinder base 202 and the horizontal loading electric cylinder frame 204 is consistent, which can achieve the self-weight offset of the horizontal loading electric cylinder 201 and related parts, and avoid the vertical loading electric cylinder 209 always bearing the self-weight load of the horizontal loading electric cylinder 201 and related parts, so that the load applied by the fixture module 3 to the typical motion pair specimen 1 of the aviation tail nozzle is composed of the output force of the horizontal loading electric cylinder 201 and the vertical loading electric cylinder 209, thereby improving the loading accuracy of the friction and wear test system of the typical motion pair of the aviation tail nozzle simulated working condition.

[0060] The motion loading module 2 also includes a vertical loading electric cylinder base 210 and a vertical loading electric cylinder guide rail 211; the vertical loading electric cylinder guide rail 211 is fixedly installed on the frame, and the vertical loading electric cylinder guide rail 211 is extended in the horizontal direction. The vertical loading electric cylinder 209 is installed on the vertical loading electric cylinder guide rail 211 through the vertical loading electric cylinder base 210, and moves in the horizontal direction along the vertical loading electric cylinder guide rail 211.

[0061] The wear test system also includes a measurement and control module 4, a temperature control module 5 and an electrical module 6; the measurement and control module 4 collects and controls the load data and motion state of each motion loading module 2, the temperature control module 5 adjusts the temperature of the test area, and the electrical module 6 supplies power to other modules.

[0062] The schematic diagram of the mechanism motion when testing the friction and wear performance of the revolute pair and the spherical pair on the triangular tie rod 101 test piece is as follows: Figure 5 As shown, under the control of the measurement and control module 4, the vertical loading electric cylinder 209 performs load output control, and the horizontal loading electric cylinder 201 performs electric cylinder telescopic motion control, so as to realize the preset motion trajectory and test load of the triangular pull rod 101 test piece.

[0063] The testing method of the wear testing system for the workpiece under test of the rotating pair includes: the fixture base 31 is rotatably connected to one end of the workpiece under test, and the other end of the workpiece under test is rotatably connected to the lower fixture 32, and the lower fixture 32 is respectively connected to the horizontal loading electric cylinder 201 and the vertical loading electric cylinder 209, and the vertical loading electric cylinder 209 applies a preset load to the workpiece under test according to the measurement and control module, and the horizontal loading electric cylinder 201 drives the workpiece under test to reciprocate, so that the workpiece under test and the fixture base 31 and the lower fixture 32 rotate.

[0064] The testing method of the wear testing system for the ball-and-socket pair workpiece includes: the fixture base 31 is rotatably connected to one end of the workpiece to be measured, the other end of the workpiece to be measured is connected to the vertical loading electric cylinder 209 through the lower fixture 32, the lower fixture 32 is rotatably connected to the workpiece to be measured through the ball-and-socket connection unit, the vertical loading motor drives the fixture base 31 to rotate, and the vertical loading electric cylinder 209 applies a load to the workpiece to be measured according to the measurement and control module 4.

[0065] The schematic diagram of the mechanism movement when testing the friction and wear performance of the cam pair on the cam roller specimen is as follows: Figure 6 As shown, the testing method of the cam roller pair workpiece by the wear testing system includes: the fixture base 31 is rotatably connected to one end of the cam skeleton 104, the driving end of the horizontal loading electric cylinder 201 is rotatably connected to the other end of the cam skeleton 104, the driving end of the vertical loading electric cylinder is rotatably connected to the roller assembly 105, and the vertical loading electric cylinder 2-9 is connected to the sensor and guide rail of the measurement and control module 4 through the fixture module 3. The vertical loading electric cylinder base 210 and the vertical loading electric cylinder guide rail 211 are constrained by geometric conditions so that horizontal slip will not occur, thereby improving the stiffness of the test system when the horizontal loading electric cylinder 201 is loaded, thereby improving the loading stability of the motion loading module 2. Under the control of the measurement and control module 4, the vertical loading electric cylinder 2-9 performs electric cylinder telescopic motion control, and the horizontal loading electric cylinder 201 performs load output control, thereby realizing the preset motion trajectory and test load of the cam roller test piece.

[0066] The present invention also discloses a friction and wear test method for a simulated working condition of an aviation tail nozzle motion pair, referring to Figure 7 As shown, the following steps are included:

[0067] Step S1: Start the electrical module 6 to transmit power to the motion loading module 2, the fixture module 3, the measurement and control module 4, and the temperature control module 5, input the preset working conditions into the measurement and control module 4, connect the workpiece to be measured to the motion loading module 2 through the fixture module 3, and place the workpiece to be measured, the fixture module 3, and the motion loading module 2 in the temperature control module 5;

[0068] Step S2: the measurement and control module 4 sends the preset temperature control information to the temperature control module 5, and the temperature control module 5 turns on the heating in the temperature control box and feeds back the temperature information to the measurement and control module 4 in real time;

[0069] Step S3: When the temperature control module 5 reaches the preset temperature, the measurement and control module 4 sends a loading start signal to the motion loading module 2, and the motion loading module 2 starts loading and feeds back the load information to the measurement and control module 4 in real time;

[0070] Step S4: When the motion loading module 2 reaches a preset load, the measurement and control module 4 sends a motion start signal to the motion loading module 2, and the motion loading module 2 starts the motion and feeds back the motion information to the measurement and control module 4 in real time;

[0071] Step S5: After the motion loading module 2 completes the specified number of motion loading cycles, the measurement and control module 4 sends an unloading cooling signal to the motion loading module 2 and the temperature control module 5, the motion loading module 2 stops moving back to the preset position and completes unloading, the temperature control module 5 stops heating and starts heat dissipation and cooling, and after the temperature of the temperature control module 5 drops to the preset safety temperature, the measurement and control module 4 prompts the termination of the test;

[0072] Step S6: remove the workpiece to be tested from the fixture module 3, and turn off the electrical module 6 to power off the test system.

[0073] The present invention further discloses a specific structure of the clamp module 3, referring to Figure 8 and Fig. 9 The fixture module includes a fixture base 31 and a lower fixture 32, the fixture base 31 includes a support seat 311 and a replaceable clamping device 312 detachably mounted on the support seat 311, the replaceable clamping device 312 is rotatably connected to the workpiece to be measured through a rotating shaft, and the lower fixture 32 is rotatably connected to the workpiece to be measured through a rotating shaft or a ball head; the friction surfaces of the replaceable clamping device 312 and the lower fixture 32 that contact the workpiece to be measured are provided with a CrN-CrAlN coating.

[0074] The support seat 311 is provided with a plurality of mounting holes 3110 and mounting grooves 3111, and the replaceable clamping device 312 can be embedded in the mounting grooves 3111 and fixed in the mounting holes 3110 by hexagonal half-thread bolts 315. The base height of the replaceable clamping device 312 is 12 mm, and the depth of the mounting groove 3111 is about 8 mm lower than the plane of the clamp base 31, ensuring that most of the replaceable clamping part is loaded into the mounting groove 3111, ensuring that the clamping is firm.

[0075] The following describes the structure of the fixture according to the type of workpiece being measured:

[0076] 1) For the wear test fixture of roller cam pair, refer to Fig.10 and Fig.11 As shown, the connection relationship between the workpiece to be measured and the replaceable clamping device 312 and the lower clamp 32 is all connected by rotating the shaft. The clamp base 31 and one of the lower clamps 32 are respectively connected to the two ends of the cam, and the other lower clamp 32 is connected to the roller.

[0077] The replaceable clamping device 312 includes an articulated support, which is provided with a rotation connection hole. The workpiece to be measured is rotatably connected to the articulated support through a pin 313 inserted in the rotation connection hole, and washers 314 are fixed at both ends of the pin 313. The inner diameter of the washer 314 is about 0.5 mm larger than the inner diameter of the pin 313, which increases the contact area of ​​the pin 313 to reduce the pressure concentration on the surface of the pin 313 and avoid damage.

[0078] The lower fixture 32 connected to the cam includes a U-shaped fixture head 321, and a rotation connection hole is opened on the U-shaped fixture head 321. The workpiece to be measured is rotationally connected to the U-shaped fixture head 321 through a lower fixture pin 325 inserted in the rotation connection hole. The inner distance of the U-shaped fixture head 321 is equal to the width of the cam. The lower fixture pin 325 is inserted into the U-shaped fixture head 321 and the cam so that the U-shaped fixture head 321 and the cam can rotate relative to each other. The lower fixture washer 326 is fixed to one side of the lower fixture pin 325.

[0079] The lower clamp connected to the roller includes a nut 323, a screw 322 and a bushing 324. The bushing 324 is sleeved on the screw 322. The sleeve is coaxial with the inner diameter of the roller. The nut 323 can be fixed at one end of the screw 322 to facilitate positioning and disassembly.

[0080] 2) For the wear test fixture of ball pairs, refer to Fig.12 As shown, the workpiece to be measured is a tripod tie rod 101, one end of the tripod tie rod 101 is rotationally connected to the replaceable clamping device 312 through a rotating shaft, and the other end of the tripod tie rod 101 is rotationally connected to the lower clamp 32 through a ball pair.

[0081] The replaceable device includes an articulated support, which is provided with a rotatable connection hole. The workpiece to be measured is rotatably connected to the articulated support via a pull rod pin 316 inserted into the rotatable connection hole, and a pin retaining spring 317 is fixed to the end of the pull rod pin 316.

[0082] The lower fixture 32 can also be composed of a pair of ear plate seats 351, a ball socket 352, a ball socket pin 353, a ball socket washer 354 and a ball socket pin 355. The ear plate seat 351 is provided with a rotation connection hole, the ball socket 352 is located between the pair of ear plate seats 351, the ball socket pin 353 is respectively penetrated in the ear plate seat 351 and the ball socket 352, the ball socket washer 354 is slidably sleeved on one side of the ball socket pin 353, and the ball socket pin 355 is inserted in the ball socket pin 353 on the side of the ball socket washer 354 for easy disassembly. A connection hole is provided at one end of the workpiece to be measured, and the ball socket 352 is built in the connection hole, and the workpiece to be measured can be rotated in multiple directions through the ball socket 352.

[0083] Reference Fig.13 As shown, the base material of the detachable clamping device and the lower clamp 32 in the device is a high-temperature alloy GH2747. Grooves are arranged along the circumferential direction on the wall of the rotating connection hole of the detachable clamping device and the lower clamp 32. The characteristic dimensions of the grooves are 0.2 mm deep and 0.2 mm wide, which is convenient for guiding the wear debris into the grooves to reduce the abrasive wear with the surface coating, so as to improve the life of the clamp coating. The CrN-CrAlN high-temperature stable anti-oxidation and wear-resistant coating with a tetragonal grain structure on the surface has anti-oxidation and wear-resistant properties in the test high-temperature environment of 800°C and the low-frequency reciprocating motion form of 1HZ, which can improve the life of the clamp. The contact surface processing method includes the following steps:

[0084] Step S1, rough machining the contact surface, turning the fixture to rotate the connecting hole, boring the circumferential groove in the hole, the machining accuracy is 15μm, and the surface roughness is Ra0.8;

[0085] Step S2, finishing the contact surface, performing precision boring on the circumferential groove structure to a surface roughness of Ra0.08, and performing mirror grinding on the connection surface to a surface roughness of Ra0.01, to facilitate subsequent coating preparation;

[0086] Step S3: Surface cleaning: spray the surface with detergent for 10 minutes at 50°C to remove surface oil stains, then place the surface in deionized water for ultrasonic cleaning at room temperature for 5 minutes, and then naturally dry it and sandblast it at room temperature for 15 minutes, then place it in anhydrous ethanol for cleaning at room temperature for 5 minutes, and then naturally dry it and place it in N2 atmosphere for plasma cleaning;

[0087] Step S4: vacuum drying, placing the fixture in a vacuum chamber, maintaining a vacuum degree of 1Pa for 20 minutes to ensure that the fixture surface is dry;

[0088] Step S5: Coating preparation, maintaining the vacuum degree of the vacuum chamber less than 5x10 -3Pa, use high-energy Ar+ particles to bombard the surface of the fixture contact surface for sputtering cleaning, use cathode arc evaporation technology, control the fixture negative bias voltage at -40V to 160V, maintain the chamber temperature at 400℃, and introduce 99.99% high-purity N2. First, use Cr target material to deposit for 20 minutes to prepare a CrN coating with a thickness of 0.5μm-0.7μm as the bottom layer. On the basis of the bottom layer, use CrAl target material to deposit for 40 minutes to prepare a CrAlN coating with a thickness of 1.5-3μm.

[0089] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0090] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A friction and wear test system for simulated working conditions of aviation tail nozzle kinematic pairs, the test system tests the rotary pair and ball-socket-ball pair of the triangular tie rod of the tested workpiece and the cam-roller pair of the cam roller of the tested workpiece; characterized in that: include: A motion loading module (2), a fixture module (3), a measurement and control module (4) and a frame (7); the motion loading module (2) is fixedly mounted on the frame (7); The motion loading module (2) comprises a horizontal loading electric cylinder (201), a vertical loading electric cylinder (209) and a vertical loading motor, and the clamp module (3) comprises a clamp base (31), a first lower clamp, a second lower clamp and a third lower clamp; The fixture base (31) drives the workpiece to be measured to rotate and load on a horizontal plane via a vertical loading motor, the vertical loading electric cylinder (209) drives the workpiece to be measured to move in a vertical direction, and the horizontal loading electric cylinder (201) drives the workpiece to be measured to move in a horizontal direction; The clamp base (31) comprises a support base (311) and a first replaceable clamping device and a second replaceable clamping device detachably mounted on the support base (311); When the wear test system tests the rotating pair of the triangular pull rod, the system comprises: the fixture base (31) is rotatably connected to one end of the triangular pull rod, the other end of the triangular pull rod is rotatably connected to the first lower fixture, the first lower fixture is respectively connected to the horizontal loading electric cylinder (201) and the vertical loading electric cylinder (209), the vertical loading electric cylinder (209) applies a preset load to the triangular pull rod according to the measurement and control module (4), and the horizontal loading electric cylinder (201) drives the triangular pull rod to reciprocate, so that the triangular pull rod, the fixture base (31) and the first lower fixture rotate; One end of the triangular pull rod (101) is rotatably connected to the first replaceable clamping device via a rotating shaft, and the other end of the triangular pull rod (101) is rotatably connected to the first lower clamp via a ball pair; The first replaceable clamping device comprises a first hinged support, the first hinged support is provided with a rotation connection hole, the triangular pull rod is rotationally connected to the first hinged support via a pull rod pin (316) inserted into the rotation connection hole, and a pin retaining spring (317) is fixed to the end of the pull rod pin (316); The first lower clamp is composed of a pair of ear plate seats (351), a ball socket (352), a ball socket pin (353), a ball socket washer (354) and a ball socket pin (355); a rotation connection hole is provided on the ear plate seat (351); the ball socket (352) is located between the pair of ear plate seats (351); the ball socket pin (353) is respectively inserted into the ear plate seat (351) and the ball socket (352); the ball socket washer (354) is slidably sleeved on one side of the ball socket pin (353); the ball socket pin (355) is inserted into the side of the ball socket pin (353) close to the ball socket washer (354); a connection hole is provided at one end of the triangular pull rod; the ball socket (352) is built in the connection hole; the triangular pull rod rotates in multiple directions through the ball socket (352); When the wear test system tests the ball-and-socket pair of the triangular tie rod, the system comprises: the fixture base (31) is rotatably connected to one end of the triangular tie rod, the other end of the triangular tie rod is connected to the vertical loading electric cylinder (209) via the first lower fixture, the first lower fixture is rotatably connected to the triangular tie rod via the ball-and-socket connection unit, the vertical loading motor drives the fixture base (31) to rotate, and the vertical loading electric cylinder (209) applies a load to the triangular tie rod according to the measurement and control module (4); One end of the triangular pull rod (101) is rotatably connected to the first replaceable clamping device via a rotating shaft, and the other end of the triangular pull rod (101) is rotatably connected to the first lower clamp via a ball pair; The first replaceable clamping device comprises a first hinged support, the first hinged support is provided with a rotation connection hole, the triangular pull rod is rotationally connected to the first hinged support via a pull rod pin (316) inserted into the rotation connection hole, and a pin retaining spring (317) is fixed to the end of the pull rod pin (316); The first lower clamp is composed of a pair of ear plate seats (351), a ball socket (352), a ball socket pin (353), a ball socket washer (354) and a ball socket pin (355); a rotation connection hole is provided on the ear plate seat (351); the ball socket (352) is located between the pair of ear plate seats (351); the ball socket pin (353) is respectively inserted into the ear plate seat (351) and the ball socket (352); the ball socket washer (354) is slidably sleeved on one side of the ball socket pin (353); the ball socket pin (355) is inserted into the side of the ball socket pin (353) close to the ball socket washer (354); a connection hole is provided at one end of the triangular pull rod; the ball socket (352) is built in the connection hole; the triangular pull rod rotates in multiple directions through the ball socket (352); When the wear test system tests the cam roller pair of the cam roller, the system comprises: the fixture base (31) is rotatably connected to one end of the cam frame (104), the drive end of the horizontal loading electric cylinder (201) is rotatably connected to the other end of the cam frame (104), the drive end of the vertical loading electric cylinder (209) is rotatably connected to the roller assembly (105), the horizontal loading electric cylinder (201) drives the cam frame (104) and the roller assembly (105) to contact and move relative to each other, and the horizontal loading electric cylinder (201) and the vertical loading electric cylinder (209) jointly apply a preset load to the cam roller according to the measurement and control module (4); The vertical loading electric cylinder (209) is connected to the sensor and guide rail of the measurement and control module (4) via the fixture module (3), and the vertical loading electric cylinder base (210) and the vertical loading electric cylinder guide rail (211) are constrained by geometric conditions so that horizontal slip does not occur; The clamp base (31) and the second lower clamp are respectively connected to two ends of the cam, and the third lower clamp is connected to the roller; The second replaceable clamping device comprises a second hinged support, the second hinged support is provided with a rotation connection hole, the cam roller is rotationally connected to the second hinged support via a pin (313) inserted into the rotation connection hole, washers (314) are fixed at both ends of the pin (313); The second lower clamp comprises a U-shaped clamp head (321), the U-shaped clamp head (321) is provided with a rotation connection hole, the cam roller is rotationally connected to the U-shaped clamp head (321) via a lower clamp pin (325) inserted into the rotation connection hole; the inner side distance of the U-shaped clamp head (321) is equal to the width of the cam, the lower clamp pin (325) is inserted into the U-shaped clamp head (321) and the cam, so that the U-shaped clamp head (321) and the cam can rotate relative to each other, and the lower clamp washer (326) is fixed to one side of the lower clamp pin (325); The third lower clamp comprises a nut (323), a screw (322) and a bushing (324); the bushing (324) is sleeved on the screw (322); the bushing (324) is coaxial with the inner diameter of the roller; and the nut (323) is fixed to one end of the screw (322).

2. The aviation tail nozzle kinematic pair simulated working condition friction and wear test system according to claim 1, characterized in that: The motion loading module (2) further comprises a horizontal loading electric cylinder base (202), a horizontal loading electric cylinder guide rail (203), a horizontal loading electric cylinder frame (204), a counterweight (205), a grooved shaft wheel (206), a counterweight steel wire (207), and a counterweight slide groove (208); The horizontal loading electric cylinder (201) is slidably mounted on an electric cylinder guide rail via the horizontal loading electric cylinder base (202); the electric cylinder guide rail is extended in a vertical direction; the electric cylinder guide rail is fixedly mounted on a frame (7); the grooved shaft wheel (206) is rotatably mounted on the frame (7); one end of the counterweight steel wire (207) is connected to the horizontal loading electric cylinder base (202); the other end of the counterweight steel wire (207) passes through the grooved shaft wheel (206) and is fixedly connected to a counterweight block (205) slidably mounted in a counterweight block slide groove (208); and the counterweight block slide groove (208) is fixedly mounted on the frame (7).

3. The aviation tail nozzle kinematic pair simulated working condition friction and wear testing system according to claim 2, characterized in that: The weight of the counterweight (205), the horizontal loading electric cylinder (201), the horizontal loading electric cylinder base (202) and the horizontal loading electric cylinder frame (204) is equal to the sum of the weights.

4. The aviation tail nozzle kinematic pair simulated working condition friction and wear testing system according to claim 1, characterized in that: The motion loading module (2) further comprises a vertical loading electric cylinder base (210) and a vertical loading electric cylinder guide rail (211); The vertical loading electric cylinder guide rail (211) is fixedly mounted on the frame (7); the vertical loading electric cylinder guide rail (211) is extended in the horizontal direction; the vertical loading electric cylinder (209) is mounted on the vertical loading electric cylinder guide rail (211) via the vertical loading electric cylinder base (210), and moves in the horizontal direction along the vertical loading electric cylinder guide rail (211).

5. The aviation tail nozzle kinematic pair simulated working condition friction and wear testing system according to claim 1, characterized in that: The measurement and control module (4) collects and controls the load data and motion state of the motion loading module (2).

6. The aviation tail nozzle kinematic pair simulated working condition friction and wear testing system according to claim 1, characterized in that: The wear testing system further comprises a temperature control module (5) and an electrical module (6); The temperature control module (5) adjusts the temperature of the test area, and the electrical module (6) supplies power to other modules.

7. A friction and wear test method for a simulated working condition of an aircraft tail nozzle kinematic pair, based on the friction and wear test system for a simulated working condition of an aircraft tail nozzle kinematic pair according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step S1: starting the electrical module (6) to transmit power to the motion loading module (2), the measurement and control module (4), and the temperature control module (5), inputting a preset working condition into the measurement and control module (4), connecting the workpiece to be measured to the motion loading module (2) via the fixture module (3), and placing the workpiece to be measured, the fixture module (3), and the motion loading module (2) in the temperature control module (5); Step S2: the measurement and control module (4) sends the preset temperature control information to the temperature control module (5), and the temperature control module (5) turns on the heating in the temperature control box and feeds back the temperature information to the measurement and control module (4) in real time; Step S3: When the temperature control module (5) reaches a preset temperature, the measurement and control module (4) sends a loading start signal to the motion loading module (2), and the motion loading module (2) starts loading and feeds back load information to the measurement and control module (4) in real time; Step S4: When the motion loading module (2) reaches a preset load, the measurement and control module (4) sends a motion start signal to the motion loading module (2), and the motion loading module (2) starts the motion and feeds back the motion information to the measurement and control module (4) in real time; Step S5: After the motion loading module (2) completes a specified number of motion loading cycles, the measurement and control module (4) sends an unloading cooling signal to the motion loading module (2) and the temperature control module (5), the motion loading module (2) stops moving and returns to a preset position and completes unloading, the temperature control module (5) stops heating and starts heat dissipation and cooling, and after the temperature of the temperature control module (5) drops to a preset safety temperature, the measurement and control module (4) prompts the termination of the test; Step S6: Remove the workpiece to be tested from the fixture module (3), turn off the electrical module (6) and power off the test system.

Images