A constant line contact friction and wear test method

Abstract

The present invention discloses a constant line contact friction and wear test method, which includes: assembling a friction and wear tester; fixing a friction plate on the bottom of a lubricating oil tank, arranging a friction ring concentrically with a main shaft and fixing it on the end of the main shaft, so that the friction ring and the friction plate form constant line contact friction; filling the lubricating oil tank with lubricating oil; starting a driving device, and driving the main shaft and the friction ring to rotate at a predetermined speed through the driving device; applying pressure to the lubricating oil tank using a loading device, so that the positive pressure between the friction plate and the friction ring reaches a predetermined positive pressure; stopping and unloading when a predetermined time is reached. The above test method can ensure the constant line contact friction of the friction pair, ensure a continuous and stable lubrication environment, and improve the accuracy of the test results.

Description

Technical Field

[0001] The invention relates to the technical field of friction testing, and in particular to a constant line contact friction and wear testing method. Background Art

[0002] All kinds of frictional relative motion between two objects will produce friction and wear. There are many factors that affect wear, such as the material, surface shape, friction motion form, working conditions and lubrication method of the friction parts. This friction and wear phenomenon will weaken the performance of machinery and equipment, and also shorten the service life of parts. Therefore, if we can correctly understand the friction and wear mechanism between objects in contact with each other, we can use it as a basis to guide social production practice, reduce unnecessary resource loss problems, and improve equipment efficiency. At the same time, it can also provide an important reference for the research of tribology and related fields.

[0003] At present, the scientific community has not yet formed a complete theoretical system for the friction and wear phenomenon between solids, and the research on its deep mechanism is not yet mature. Therefore, it is difficult to determine the various properties of friction pairs through theoretical analysis. However, in the industrial production process, in order to correctly design the matching relationship between friction parts, it is necessary to correctly and effectively evaluate the friction characteristics of friction pairs. Therefore, it is necessary to design appropriate friction and wear test methods to study the friction coefficient, wear characteristics and other related indicators between the corresponding materials.

[0004] In the existing line contact friction and wear test method, a line contact friction and wear test is performed on the two test pieces by rotating one test piece relative to another test piece. Since the test piece will inevitably vibrate during the rotation process and the friction force sensor measurement process will destroy the contact state between the friction pairs, the existing test method has the problem that the line contact friction pairs cannot accurately maintain balance and stable line contact. This problem may cause uneven load loading and inaccurate results. In addition, the existing line contact friction and wear test process often cannot provide a continuous and stable lubrication environment. Summary of the invention

[0005] In view of this, the present invention provides a constant line contact friction and wear test method, which can ensure the constant line contact friction of the friction pair and can ensure a continuous and stable lubrication environment, thereby improving the accuracy of the test results.

[0006] The present invention adopts the following specific technical solutions:

[0007] A constant line contact friction and wear test method, the test method comprising the following steps:

[0008] Assemble a friction and wear testing machine, which includes a base, a spindle, a driving device, a loading device, a lubricating oil tank, a detection device and a control device; the spindle can be supported on the base so as to rotate around a horizontal axis; the driving device is fixedly installed on the base and is connected to the spindle by transmission; the loading device is installed on the base and the spindle and is used to apply positive pressure to the line contact friction pair; the lubricating oil tank is installed on the loading device so as to swing around the spindle axis and the longitudinal axis, and the spindle axis and the longitudinal axis intersect vertically in a horizontal plane; the detection device is used to detect the positive pressure and friction force of the line contact friction pair; the control device is connected to the detection device and the driving device by signal;

[0009] The friction plate is fixedly installed at the bottom of the lubricating oil groove, and the friction ring is arranged concentrically with the main shaft and fixedly installed at the end of the main shaft, so that the friction ring and the friction plate form a constant line contact friction;

[0010] Fill lubricating oil into the lubricating oil tank;

[0011] Turn on the driving device, and drive the main shaft and the friction ring to rotate at a predetermined speed through the driving device;

[0012] Applying pressure to the lubricating oil groove by using a loading device so that the positive pressure between the friction plate and the friction ring reaches a predetermined positive pressure;

[0013] When the scheduled time is reached, the machine will be shut down for unloading.

[0014] Furthermore, the driving device includes a motor, a transmission belt, a sleeve, a support plate and a swing bracket;

[0015] The motor is fixedly mounted on the base, and the output shaft of the motor is connected to the main shaft through the transmission belt;

[0016] The shaft sleeve is fixedly mounted on the base through the support plate;

[0017] The main shaft is installed in the sleeve through a bearing, and the axis of the main shaft is arranged parallel to the axis of the motor;

[0018] The swing bracket is mounted on one end of the sleeve close to the friction ring so as to be swingable around the axis of the main shaft, and is used to support the loading device; the swing bracket is a hollow block structure, and has at least four side surfaces evenly distributed along the circumferential direction;

[0019] The control device is connected to the motor signal and is used to control the motor and obtain the working state information of the motor.

[0020] Furthermore, the loading device includes two adjustable outer rails, a loading outer frame, a loading bottom plate, a loading platform, a guide force component frame, an upper slide rail, a fulcrum frame, a lever, a guide seat, a weight, a guide rope and a loading rope;

[0021] The two adjustable outer rails are symmetrically distributed on both sides of the swing bracket and can slide along the axial direction of the main shaft. The central axis of the adjustable outer rail is parallel to the axis of the main shaft and has the same height;

[0022] The loading outer frame capable of swinging around the longitudinal axis and the axis of the main shaft is installed between the two adjustable outer rails;

[0023] Sliding guide rails extending in the vertical direction are arranged at the four inner corners of the loading outer frame;

[0024] In the vertical direction, the loading platform is spaced apart from the top of the loading base plate; the outer peripheral surfaces of the loading platform and the loading base plate are both slidably matched with the inner side surface of the sliding guide rail;

[0025] The detection device comprises a positive pressure sensor fixedly mounted on the top surface of the loading base plate, and the positive pressure sensor is used to detect the positive pressure applied by the loading base plate to the object loading platform;

[0026] The lubricating oil tank is fixedly installed on the top of the loading platform;

[0027] The loading device drives the friction plate to apply positive pressure to the friction ring through the loading bottom plate;

[0028] The fulcrum frame is fixedly mounted on the top of the swing bracket, and the upper slide rail is pressed onto the top of the swing bracket;

[0029] The top end of the guide force component frame is fixedly mounted on the end of the upper slide rail and is an inverted U-shaped structure, with guide grooves and fixed pulleys for guiding the loading ropes being arranged on both sides;

[0030] The central axis of the lever and the axis of the main shaft are located in the same vertical plane, and the central axis of the upper slide rail and the central axis of the lever are arranged in parallel; the lever is arranged in parallel with the main shaft, and the middle part is swingably mounted on the top of the fulcrum frame through a hinge seat, one end of which is hinged to a hanging seat through a rotating shaft, and the other end is connected to the guide rope; the swing axis of the lever is parallel to the longitudinal axis; the top end of the hanging seat can swing around the axis of the rotating shaft, and the axis of the rotating shaft is parallel to the longitudinal axis and located in the same vertical plane; a roller is installed at the bottom end of the hanging seat, and the axis of the roller is parallel to the axis of the main shaft and located in the same vertical plane;

[0031] The loading rope is a closed loop structure, with the top suspended on the roller, the bottom sleeved on the outer peripheral side of the loading base plate, and the middle portion guided by the guide groove and fixed pulley of the guide force component frame, and the fixed pulleys on both sides of the loading base plate;

[0032] The bottom end of the guide rope passes around the guide seat and is connected to the weight;

[0033] The guide seat is fixedly mounted on the base and located at the bottom of the lever, and is internally provided with two fixed pulleys rotating around a horizontal axis for controlling the middle portion of the guide rope to extend in a horizontal direction through the two fixed pulleys.

[0034] Furthermore, the detection device also includes a sensor support and a friction sensor;

[0035] The sensor support is fixedly mounted on the base;

[0036] The friction force sensor is fixedly mounted on the top of the sensor support and connected to the swing bracket to detect the friction force transmitted by the swing bracket.

[0037] Furthermore, the friction and wear testing machine further comprises a display device connected to the control device by signal and a rotation speed sensor installed on the motor;

[0038] According to the signal obtained by the control device, the display device is used to display the working status information of the motor, the values ​​collected by the friction sensor and the positive pressure sensor;

[0039] The speed sensor is connected to the control device by signal and is used to detect the speed of the motor;

[0040] The motor is fixedly mounted on the bottom of the base, and a rubber gasket is sandwiched between the motor and the base;

[0041] The base is provided with a notch for the transmission belt to pass through.

[0042] Furthermore, a threaded hole is provided on the end surface of the main shaft; the friction ring is mounted on the main shaft through the first locking bolt;

[0043] The friction plate is an annular plate provided with a central through hole, and is mounted on the lubricating oil groove via a second locking bolt passing through the central through hole; the friction plate can be reused by rotating.

[0044] Beneficial effects:

[0045] (1) The constant line contact friction and wear test method of the present invention comprises: assembling a friction and wear testing machine; fixing a friction plate on the bottom of a lubricating oil tank, arranging a friction ring concentrically with a main shaft and fixing it on the end of the main shaft, so that the friction ring and the friction plate form a constant line contact friction; filling the lubricating oil tank with lubricating oil; starting a driving device, and driving the main shaft and the friction ring to rotate at a predetermined speed through the driving device; applying pressure to the lubricating oil tank by a loading device, so that the positive pressure between the friction plate and the friction ring reaches a predetermined positive pressure; and stopping and unloading after a predetermined time. The friction and wear tester assembled in the above test method steps is supported on the base with a main shaft and a driving device, the friction ring is installed on the end of the main shaft, the main shaft is driven to rotate by the driving device to drive the friction ring to rotate synchronously, and the friction plate is installed on the inner bottom of the lubricating oil groove, so that the friction ring and the friction plate are subjected to line contact friction; the friction test under different pressure conditions is realized by the positive pressure applied by the loading device; the lubricating oil groove can swing around the axis of the main shaft and the longitudinal axis, so that the friction plate and the friction ring can always maintain a constant line contact friction state; at the same time, the positive pressure and friction force between the friction plate and the friction ring can be detected by the detection device, so as to facilitate the real-time acquisition of test data. The above test method can realize the constant line contact friction between the friction ring and the friction plate constituting the line contact friction pair, ensure the continuous and stable lubrication environment of the line contact friction pair by the step of filling the lubricating oil into the lubricating oil, control the rotation speed of the friction ring by the driving device, and ensure the loading accuracy of the positive pressure between the friction plate and the friction ring by the loading device, so as to improve the accuracy of the test results.

[0046] Therefore, the above test method can ensure the constant line contact condition of the line contact friction pair, ensure a continuous and stable lubrication environment, and improve the accuracy of the friction and wear test results.

[0047] (2) The test method of the present invention is carried out by a friction and wear testing machine. The friction and wear testing machine has a shaft sleeve installed on the base through a support plate. The main shaft is rotatably installed in the shaft sleeve and driven by a motor. Since the swing bracket is swingably installed on the shaft sleeve and the supporting loading device has the swing freedom around the axis of the main shaft, the friction plate can swing with the friction ring under the friction with the friction ring, thereby avoiding the deformation of the sensitive element of the friction force sensor causing the friction plate to swing around the axis of the main shaft, causing the loading force to be not perpendicular to the contact surface, and overcoming the principle defect that the friction sensor will affect the contact state of the friction pair during the friction force measurement process, ensuring that the positive pressure is always perpendicular to the contact surface during the friction force measurement process, and improving the test results. The accuracy and repeatability of the test are ensured; the loading device is composed of two adjustable outer rails, a loading outer frame, a loading base plate, a loading platform, a guide force component frame, an upper slide rail, a fulcrum frame, a lever, a guide seat, a weight, a guide rope and a loading rope. Since the loading outer frame can be installed between the two adjustable outer rails in a swingable manner around the longitudinal axis, and the adjustable outer rail can swing with the swing bracket around the axis center line of the main shaft, it is ensured that the friction plate can swing synchronously with the swing bracket around the axis center line of the main shaft, and can also swing synchronously with the loading outer frame around the longitudinal axis during the loading process, so that the friction plate and the loading device move synchronously, and the force applied by the loading device just passes through the friction contact position between the friction ring and the friction plate, thereby further improving the accuracy of the test results.

[0048] (3) The test method of the present invention can measure the friction force between the friction plate and the friction ring in real time through the friction force sensor of the detection device, and can measure the positive pressure applied between the friction plate and the friction ring by the loading device in real time through the positive pressure sensor of the detection device. The friction and positive pressure data measured in real time can be used to analyze and study the mechanism of friction and wear, and the friction characteristics of the friction pair can be further evaluated and predicted, which can provide a theoretical basis for engineering applications.

[0049] (4) In the test method of the present invention, the friction ring is fixed to the main shaft by the first locking bolt, and the friction plate is installed in the lubricating oil tank by the second locking bolt. After a single friction and wear test is completed, the friction plate can be rotated to a certain angle and then fixed, and the surface portion of the friction plate that does not participate in the friction is used as the friction pair contact surface of the next test to avoid replacing a new friction plate. The friction plate can be repeatedly used by rotating it, which not only avoids the test error caused by different surface processing quality when replacing the friction plate, but also reduces the waste of test pieces, greatly improves the utilization rate of the test pieces, reduces unnecessary waste, and is conducive to saving test costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a flow chart of the constant line contact friction and wear test method of the present invention;

[0051] Figure 2It is a structural schematic diagram of a testing machine used in the constant line contact friction and wear testing method of the present invention;

[0052] Figure 3 for Figure 2 Schematic diagram of the explosion structure of the test machine.

[0053] Among them, 1-base, 2-main support plate, 3-auxiliary support plate, 4-motor, 5-transmission belt, 6-spindle, 7-swing bracket, 8-adjustable outer rail, 9-loading outer frame, 10-loading bottom plate, 11-carrying platform, 12-guide component frame, 13-fulcrum frame, 14-lever, 15-guide seat, 16-weight, 17-guide rope, 18-lubricating oil groove, 19-friction ring, 20-sensor support, 21-friction force sensor, 22-positive pressure sensor, 23-first locking bolt, 24-second locking bolt, 25-friction plate, 26-upper slide rail, 27-loading rope, 28-bushing, 29-guide groove, 30-fixed pulley, 31-articulated seat, 32-rotating shaft, 33-lifting seat, 34-roller DETAILED DESCRIPTION

[0054] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0055] The embodiment of the present invention provides a constant line contact friction and wear test method, such as Figure 1 As shown, the test method includes the following steps:

[0056] Step S10, assembling a friction and wear testing machine; the specific structure of the friction and wear testing machine is as follows Figure 2 and Figure 3 For the convenience of explanation, in the embodiments of the present invention, the Figure 2 The direction from left to right in the middle page is defined as the horizontal direction, which is the axial direction of the main axis 6. Figure 2 The direction from top to bottom of the page is defined as the vertical direction, perpendicular to the Figure 2The direction of the middle page is defined as the longitudinal direction, which is the extension direction of the longitudinal axis; the friction and wear testing machine includes a base 1, a spindle 6, a driving device, a loading device, a lubricating oil tank 18, a detection device and a control device; the base 1 is the foundation of the friction and wear testing machine; the spindle 6 can be supported on the base 1 so as to rotate around a horizontal axis, and the spindle 6 extends in the transverse direction; the driving device is fixedly installed on the base 1, and is connected to the spindle 6 for driving the spindle 6 to rotate, and the speed of the spindle 6 can be adjusted by the driving device; the spindle 6 is used to fix the friction ring 19 constituting the line contact friction pair; the loading device is installed on the base 1 and the spindle 6, and is used to apply positive pressure to the line contact friction pair; The lubricating oil groove 18 can be installed on the loading device so as to swing around the axis and longitudinal axis of the main shaft 6. The axis and longitudinal axis of the main shaft 6 intersect vertically in the horizontal plane, that is, the axis and longitudinal axis of the main shaft 6 are both in the same horizontal plane and the axis and longitudinal axis of the main shaft 6 intersect vertically; an opening is provided at the top of the lubricating oil groove 18, so that the friction ring 19 can enter the lubricating oil groove 18 to contact and rub with the friction plate 25, and lubricating oil forming a lubricating environment is contained inside; the detection device is used to detect the positive pressure and friction force of the line contact friction pair; the control device is connected with the detection device and the drive device by signal, and is used to control the drive device and obtain the detection signal of the detection device;

[0057] Step S20, fix the friction plate 25 to the bottom of the lubricating oil groove 18, arrange the friction ring 19 concentrically with the main shaft 6 and fix it to the end of the main shaft 6, so that the friction ring 19 and the friction plate 25 form a constant line contact friction; the line contact friction pair is composed of the friction ring 19 and the friction plate 25, and a constant line contact friction is formed between the outer peripheral surface of the friction ring 19 and the surface of the friction plate 25; the friction plate 25 can be an annular plate provided with a central through hole, and is installed in the lubricating oil groove 18 by a second locking bolt 24 penetrated through the central through hole; the friction plate 25 can be repeatedly used by rotating; the friction ring 19 is arranged concentrically with the main shaft 6 and can be detachably installed at the end of the main shaft 6; in order to facilitate the fixed installation of the friction ring 19, a threaded hole is arranged on the end face of the main shaft 6, and the friction ring 19 is installed on the main shaft 6 by a first locking bolt 23 threadedly connected to the threaded hole at the end of the main shaft 6; the end face of the friction ring 19 is arranged parallel to the end face of the main shaft 6;

[0058] Step S30, adding lubricating oil into the lubricating oil tank 18, the type and depth of the lubricating oil in the lubricating oil tank 18 are determined according to the test conditions;

[0059] Step S40, turning on the driving device, and driving the main shaft 6 and the friction ring 19 to rotate at a predetermined speed through the driving device; the driving device can make the speed of the friction ring 19 reach a predetermined speed, and the predetermined speed is determined according to the speed required by the test method;

[0060] Step S50, applying pressure to the lubricating oil groove 18 by using a loading device so that the positive pressure between the friction plate 25 and the friction ring 19 reaches a predetermined positive pressure; the positive pressure between the friction plate 25 and the friction ring 19 is applied by the loading device, and the predetermined positive pressure between the friction plate 25 and the friction ring 19 is determined according to the test conditions;

[0061] Step S60, when the predetermined time is reached, the machine is stopped and unloaded; when the friction plate 25 and the friction ring 19 are tested at a predetermined rotation speed and a predetermined positive pressure, and the friction time reaches the predetermined time required by the test conditions, the driving device is controlled to stop rotating, the loading device is unloaded, and the friction plate 25 and the friction ring 19 are disassembled, so as to measure, analyze and study the friction surfaces of the friction plate and the friction ring, etc., and the friction coefficient can also be calculated through the collected data, and the wear characteristics can be analyzed.

[0062] When the above-mentioned constant line contact friction and wear test method is used for testing, it is first necessary to assemble a friction and wear testing machine, on which a main shaft 6 and a driving device are supported on a base 1 of the friction and wear testing machine, a friction ring 19 is installed on the end of the main shaft 6, and the main shaft 6 is driven to rotate by the driving device, thereby driving the friction ring 19 to rotate synchronously, and a friction plate 25 is installed on the inner bottom of the lubricating oil groove 18, so that the friction ring 19 and the friction plate 25 are in line contact friction; the positive pressure applied by the loading device is used to realize friction tests under different pressure conditions; the lubricating oil groove 18 can swing around the axis and longitudinal axis of the main shaft 6, so that the friction plate 25 can always maintain a constant line contact friction state with the friction ring 19; at the same time, the positive pressure and friction force between the friction plate 25 and the friction ring 19 can be detected by the detection device, so as to facilitate the real-time acquisition of test data. The steps of the above-mentioned test method can achieve steady-state line contact friction between the friction ring 19 and the friction plate 25 that constitute the line contact friction pair. The continuous and stable lubrication environment of the line contact friction pair is ensured by adding lubricating oil into the lubricating oil. The rotation speed of the friction ring 19 is controlled by the driving device, and the loading accuracy of the positive pressure between the friction plate 25 and the friction ring 19 is ensured by the loading device, thereby improving the accuracy of the test results.

[0063] Therefore, the above test method can ensure the constant line contact condition of the line contact friction pair, ensure a continuous and stable lubrication environment, and improve the accuracy of the friction and wear test results.

[0064] In the above test method, the friction ring 19 is fixedly installed on the main shaft 6 by the first locking bolt 23, and the friction plate 25 is installed on the lubricating oil groove 18 by the second locking bolt 24. After a single friction and wear test is completed, the friction plate 25 can be rotated by a certain angle and then fixed, and the surface part of the friction plate 25 that does not participate in the friction is used as the friction pair contact surface of the next test to avoid replacing a new friction plate 25. By rotating the friction plate 25, the same friction plate 25 can be reused multiple times, which not only avoids the test error caused by different surface processing quality when replacing the friction plate 25, but also reduces the waste of test pieces, greatly improves the utilization rate of the test pieces, reduces unnecessary waste, and is conducive to saving test costs.

[0065] In a specific implementation manner, Figure 2 and Figure 3 As shown in the structure, in step S10 of assembling the friction and wear testing machine, the driving device includes a motor 4, a transmission belt 5, a sleeve 28, a support plate and a swing bracket 7;

[0066] The motor 4 is fixedly mounted on the base 1, and the output shaft of the motor 4 is connected to the main shaft 6 through the transmission belt 5; the motor 4 is fixedly mounted on the bottom of the base 1, and a rubber gasket is sandwiched between the motor 4 and the base 1; the base 1 is provided with a notch for the transmission belt 5 to pass through;

[0067] The shaft sleeve 28 is fixedly mounted on the base 1 through a support plate; Figure 2 and Figure 3 As shown in the structure, the support plate may include a main support plate 2 and a secondary support plate 3 arranged in the vertical direction; the main support plate 2 and the secondary support plate 3 form a highly rigid frame structure to provide effective support for the main shaft 6;

[0068] The main shaft 6 is installed in the shaft sleeve 28 through a bearing, and the axis of the main shaft 6 is arranged parallel to the axis of the motor 4;

[0069] The swing bracket 7 can be installed on one end of the sleeve 28 close to the friction ring 19 so as to swing around the axis of the main shaft 6, and is used to support the loading device and enable the loading device to have the freedom of swinging around the axis of the main shaft 6; the swing bracket 7 is a hollow block structure, and has at least four side surfaces evenly distributed along the circumferential direction; the swing bracket 7 is provided with a bearing through hole, and a bearing is installed in the bearing through hole, and the bearing is sleeved on the outer peripheral side of the sleeve 28, and the swing bracket 7 is rotated relative to the sleeve 28 through the bearing; the rotation axis of the swing bracket 7 coincides with the axis of the main shaft 6;

[0070] The control device is connected to the motor 4 signal, and is used to control the motor 4 and obtain the working state information of the motor 4;

[0071] like Figure 2 and Figure 3As shown in the structure, the loading device includes two adjustable outer rails 8, a loading outer frame 9, a loading bottom plate 10, a loading platform 11, a guide force component frame 12, an upper slide rail 26, a fulcrum frame 13, a lever 14, a guide seat 15, a weight 16, a guide rope 17 and a loading rope 27;

[0072] The two adjustable outer rails 8 are symmetrically distributed on both sides of the swing bracket 7 and can slide along the axial direction of the main shaft 6. The central axis of the adjustable outer rail 8 is parallel to the axis of the main shaft 6 and has the same height; Figure 2 and Figure 3 As shown in the structure, a fixed slider is fixedly installed on the surface of one side corresponding to the swing bracket 7 and the adjustable outer rail 8, and the adjustable outer rail 8 and the fixed slider are slidably matched to realize the sliding adjustment of the adjustable outer rail 8 relative to the swing bracket 7; the fixed slider and the swing bracket 7 can be a separate structure or an integral structure; the axial position adjustment of the loading outer frame 9 along the main shaft 6 can be realized through the adjustable outer rail 8;

[0073] A loading outer frame 9 capable of swinging around the longitudinal axis and the axis center line of the main shaft 6 is installed between the two adjustable outer rails 8; a mounting hole is provided at one end of the adjustable outer rail 8 facing the lubricating oil groove 18, that is, at one end of the adjustable outer rail 8 away from the swing bracket 7, and the axis center line of the mounting hole coincides with the longitudinal axis; the loading outer frame 9 is provided with a rotating shaft 32 corresponding to the position of the mounting hole, and the loading outer frame 9 is installed between the two symmetrically arranged adjustable outer rails 8 through the rotational cooperation between the rotating shaft 32 and the mounting hole; a bearing can also be installed between the rotating shaft 32 and the mounting hole; through the rotational cooperation between the adjustable outer rail 8 and the loading outer frame 9, the swinging freedom of the loading device along the longitudinal axis can be released;

[0074] Sliding guide rails extending in the vertical direction are arranged at the four inner corners of the loading outer frame 9; the loading outer frame 9 is a frame structure, and four vertical sliding guide rails are arranged inside the frame structure to guide the movement direction of the loading base plate 10 and the loading platform 11;

[0075] In the vertical direction, the loading platform 11 is arranged at intervals on the top of the loading base plate 10; the outer peripheral surfaces of the loading platform 11 and the loading base plate 10 are both slidably matched with the inner side surface of the sliding guide rail; fixed pulleys 30 are symmetrically arranged on both sides of the loading base plate 10 to roll with the loading rope 27;

[0076] The detection device includes a positive pressure sensor 22 fixedly mounted on the top surface of the loading base plate 10; the positive pressure sensor 22 is installed between the loading base plate 10 and the loading platform 11, and is used to detect the positive pressure applied by the loading base plate 10 to the loading platform 11, thereby measuring the positive pressure between the friction plate 25 and the friction ring 19;

[0077] The lubricating oil tank 18 is fixedly mounted on the top of the loading platform 11;

[0078] The loading device drives the friction plate 25 to apply positive pressure to the friction ring 19 through the loading base plate 10;

[0079] The fulcrum frame 13 is fixedly mounted on the top of the swing bracket 7, and the upper slide rail 26 is pressed against the top of the swing bracket 7; the fulcrum frame 13 may be an H-shaped structure;

[0080] The top of the guide force component frame 12 is fixedly mounted on the end of the upper slide rail 26 and is an inverted U-shaped structure, with guide grooves 29 and fixed pulleys 30 for guiding the loading rope 27 provided on both sides;

[0081] The central axis of the lever 14 and the axis of the main shaft 6 are located in the same vertical plane, and the central line of the upper slide rail 26 and the central axis of the lever 14 are arranged in parallel; the lever 14 is arranged in parallel with the main shaft 6, and the middle part is swingably mounted on the top of the fulcrum frame 13 through a hinge seat 31, one end of which is hinged to a hanging seat 33 through a rotating shaft 32, and the other end is connected to a guide rope 17; the swing axis of the lever 14 is parallel to the longitudinal axis; the top end of the hanging seat 33 can swing around the axis of the rotating shaft 32, and the axis of the rotating shaft 32 is parallel to the longitudinal axis and located in the same vertical plane; the bottom end of the hanging seat 33 is installed with a roller 34, and the axis of the roller 34 is parallel to the axis of the main shaft 6 and located in the same vertical plane;

[0082] The loading rope 27 is a closed loop structure, with the top suspended on the roller 34, the bottom sleeved on the outer peripheral side of the loading base plate 10, and the middle portion guided by the guide groove 29 and the fixed pulley 30 of the guide force component frame 12, as well as the fixed pulleys 30 on both sides of the loading base plate 10; during the loading process, the loading rope 27 is in a taut state, and the loading force generated by the lever 14 can be transmitted to the loading base plate 10; when two loading ropes 27 are used, the lengths of the two loading ropes 27 are the same;

[0083] The bottom end of the guide rope 17 passes around the guide seat 15 and is connected to the weight 16;

[0084] The guide seat 15 is fixedly installed on the base 1 and is located at the bottom of the lever 14. Two fixed pulleys 30 that rotate around a horizontal axis are arranged inside the guide seat 15, which are used to control the middle part of the guide rope 17 to extend in the horizontal direction through the two fixed pulleys 30; the central axes of the two fixed pulleys 30 installed inside the guide seat 15 are arranged in parallel and can be arranged in parallel with the longitudinal axis, so that the guide rope 17 bypasses the part between the two fixed pulleys 30 in the guide seat 15 and is parallel to the axis center line of the main shaft 6; the loading force generated by the gravity of the weight 16 is transmitted to the lever 14 through the guide rope 17.

[0085] The above test method is carried out by a friction and wear testing machine. A sleeve 28 is installed on the base 1 through a support plate. The main shaft 6 is rotatably installed in the sleeve 28 and driven by a motor 4. Since the swing bracket 7 is swingably installed on the sleeve 28 and supports the loading device to have the swing freedom around the axis of the main shaft 6, the loading outer frame 9 can be made to have the swing freedom along the longitudinal axis, so that the friction plate 25 can swing with the friction ring 19 under the friction with the friction ring 19, thereby avoiding the deformation of the sensitive element of the friction force sensor causing the friction plate 25 to swing around the axis of the main shaft 6, causing the loading force to be not perpendicular to the contact surface, and overcoming the principle defect that the friction sensor 21 will affect the contact state of the friction pair during the friction measurement process, ensuring that the positive pressure is always perpendicular to the contact surface during the friction measurement process, and improving the test results. Accuracy and repeatability; the loading device is composed of two adjustable outer rails 8, a loading outer frame 9, a loading base plate 10, a loading platform 11, a guide force component frame 12, an upper slide rail 26, a fulcrum frame 13, a lever 14, a guide seat 15, a weight 16, a guide rope 17 and a loading rope 27. Since the loading outer frame 9 can be installed between the two adjustable outer rails 8 in a swingable manner around the longitudinal axis, and the adjustable outer rail 8 can swing around the axis center line of the main shaft 6 with the swing bracket 7, it is ensured that the friction plate 25 of the loading device can swing synchronously with the swing bracket 7 around the axis center line of the main shaft 6, and can also swing synchronously with the loading outer frame 9 around the longitudinal axis during the loading process, so that the friction plate 25 moves synchronously with the loading device, so that the force applied by the loading device just passes through the friction contact position between the friction ring 19 and the friction plate 25, further improving the accuracy of the test results.

[0086] Since a rubber gasket is sandwiched between the motor 4 and the base 1 , the vibration of the motor 4 can be isolated by the rubber gasket, thereby reducing the test error caused by the vibration of the motor 4 itself when it is working.

[0087] Furthermore, in the friction and wear testing machine used in the above test method, the detection device also includes a sensor support 20 and a friction sensor 21; the sensor support 20 is fixedly installed on the base 1; the sensor support 20 can be an L-shaped structure, with a small hole on the top for installing the friction sensor 21, the friction sensor 21 is fixedly installed on the top of the sensor support 20, and is connected to the swing bracket 7, for detecting the friction force transmitted by the swing bracket 7. The friction sensor 21 can be connected to the swing bracket 7 through a T-shaped plate. When the swing bracket 7 is subjected to the friction force transmitted by the friction plate 25, the friction sensor 21 will generate a corresponding deformation signal due to the tension; the positive pressure sensor 22 is fixedly installed on the top surface of the loading base plate 10, and is used to detect the positive pressure applied by the loading base plate 10 to the loading platform 11; when the loading base plate 10 is subjected to the loading force, the loading base plate 10 will slide upward under the action of the loading force, so that the positive pressure sensor 22 contacts the loading platform 11; when the loading process is completed, the positive pressure sensor 22 is squeezed and deformed accordingly by the loading force, and a deformation signal is generated; the control device is connected to the friction sensor 21 and the positive pressure sensor 22 signals, and is used to obtain real-time measurement of positive pressure and friction.

[0088] The above test method can measure the friction force between the friction plate 25 and the friction ring 19 in real time through the friction force sensor 21 of the detection device, and can measure the positive pressure applied by the loading device between the friction plate 25 and the friction ring 19 in real time through the positive pressure sensor 22 of the detection device. The real-time measured friction force and positive pressure data can be used to analyze and study the mechanism of friction and wear, and further evaluate and predict the friction characteristics of the friction pair, which can provide a theoretical basis for engineering applications.

[0089] On the basis of the various embodiments described above, the friction and wear testing machine used in the above test method also includes a display device (not shown in the figure) connected to the control device signal and a speed sensor (not shown in the figure) installed on the motor 4; according to the signal obtained by the control device, the display device is used to display the working status information of the motor 4, the values ​​collected by the friction force sensor 21 and the positive pressure sensor 22; the speed sensor is connected to the control device signal and is used to detect the speed of the motor 4.

[0090] The display device is provided to facilitate displaying various working parameters of the testing machine and the collected detection values; the rotation speed of the motor 4 can be conveniently detected by the rotation speed sensor, and the relative speed between the friction plate 25 and the friction ring 19 can be monitored and adjusted by the rotation speed sensor and the control device.

[0091] During the test using the above test method, the loading force is transmitted to the loading base plate 10 through the loading rope 27. The loading base plate 10 moves upward along the sliding guide rail due to the limitation of the sliding guide rail of the loading outer frame 9. The positive pressure sensor 22 moves with the loading base plate 10, thereby pushing the loading platform 11 to move upward. The lubricating oil groove 18 is fixed on the loading platform 11 and moves upward with the loading platform 11. Since the friction plate 25 is fixedly installed on the inner bottom of the lubricating oil groove 18, the friction plate 25 moves upward with the lubricating oil groove 18. After the surface of the friction plate 25 is tangent to and completely fits the outer peripheral surface of the friction ring 19, the loading base plate 10 can no longer move upward, the friction pair is subjected to the corresponding loading force, the friction pair is in a linear contact state, and the loading process is completed. When the outer surface of the friction ring 19 is not tangent to the surface of the friction plate 25 due to external factors, the friction pair is out of line contact, and a certain angle appears on the corresponding contact surface, and a rotation torque is generated between the two planes; since the friction ring 19 is a fixed structure, the rotation torque finally acts on the loading device, causing the loading outer frame to swing around its rotation axis 32 in the direction of reducing the angle of the contact surface, and the end surface of the friction plate 25 swings accordingly with the loading outer frame; when the outer surface of the friction ring 19 is tangent to the end surface of the friction plate 25 again, the rotation torque acting between the two planes disappears, and the friction pair resumes the line contact state. When the motor 4 is running, the friction ring 19 rotates with the main shaft 6, and the outer surface of the friction ring 19 and the end surface of the friction plate 25 will always be tangent under the action of the above-mentioned restoring torque, so that the friction ring 19 and the friction plate 25 are always in a stable line contact state.

[0092] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A constant line contact friction and wear test method, characterized in that: The following steps are involved: Assemble a friction and wear testing machine, which includes a base, a spindle, a driving device, a loading device, a lubricating oil tank, a detection device and a control device; the spindle can be supported on the base so as to rotate around a horizontal axis; the driving device is fixedly installed on the base and is connected to the spindle by transmission; the loading device is installed on the base and the spindle and is used to apply positive pressure to the line contact friction pair; the lubricating oil tank is installed on the loading device so as to swing around the spindle axis and the longitudinal axis, and the spindle axis and the longitudinal axis intersect vertically in a horizontal plane; The detection device is used to detect the normal pressure and friction force of the line contact friction pair; the control device is connected with the detection device and the drive device by signal; The friction plate is fixedly installed at the bottom of the lubricating oil groove, and the friction ring is arranged concentrically with the main shaft and fixedly installed at the end of the main shaft. The lubricating oil groove can swing around the axis and longitudinal axis of the main shaft, so that the friction plate and the friction ring can always maintain a constant linear contact friction state; When the outer peripheral surface of the friction ring and the surface of the friction plate are not tangent due to external factors, the friction pair is out of line contact, and a certain angle appears on the corresponding contact surface, and a rotation torque is generated between the two planes; since the friction ring is a fixed structure, the rotation torque finally acts on the loading device, causing the loading device to swing around its rotation axis in the direction of reducing the angle of the contact surface, and the end surface of the friction plate swings accordingly with the loading device; when the outer peripheral surface of the friction ring and the end surface of the friction plate are tangent again, the rotation torque acting between the two planes disappears, and the friction pair resumes the line contact state; Fill lubricating oil into the lubricating oil tank; Turn on the driving device, and drive the main shaft and the friction ring to rotate at a predetermined speed through the driving device; Applying pressure to the lubricating oil groove by using a loading device so that the positive pressure between the friction plate and the friction ring reaches a predetermined positive pressure; When the scheduled time is reached, the machine will be shut down for unloading.

2. The test method according to claim 1, characterized in that: The driving device includes a motor, a transmission belt, a shaft sleeve, a support plate and a swing bracket; The motor is fixedly mounted on the base, and the output shaft of the motor is connected to the main shaft through the transmission belt; The shaft sleeve is fixedly mounted on the base through the support plate; The main shaft is installed in the sleeve through a bearing, and the axis of the main shaft is arranged parallel to the axis of the motor; The swing bracket is mounted on one end of the sleeve close to the friction ring so as to be swingable around the axis of the main shaft, and is used to support the loading device; the swing bracket is a hollow block structure, and has at least four side surfaces evenly distributed along the circumferential direction; The control device is connected to the motor signal and is used to control the motor and obtain the working state information of the motor.

3. The test method according to claim 2, characterized in that: The loading device comprises two adjustable outer rails, a loading outer frame, a loading bottom plate, a loading platform, a guide force component frame, an upper slide rail, a fulcrum frame, a lever, a guide seat, a weight, a guide rope and a loading rope; The two adjustable outer rails are symmetrically distributed on both sides of the swing bracket and can slide along the axial direction of the main shaft. The central axis of the adjustable outer rail is parallel to the axis of the main shaft and has the same height; The loading outer frame capable of swinging around the longitudinal axis and the axis of the main shaft is installed between the two adjustable outer rails; Sliding guide rails extending in the vertical direction are arranged at the four inner corners of the loading outer frame; In the vertical direction, the loading platform is spaced apart from the top of the loading base plate; the outer peripheral surfaces of the loading platform and the loading base plate are both slidably matched with the inner side surface of the sliding guide rail; The detection device comprises a positive pressure sensor fixedly mounted on the top surface of the loading base plate, and the positive pressure sensor is used to detect the positive pressure applied by the loading base plate to the object loading platform; The lubricating oil tank is fixedly installed on the top of the loading platform; The loading device drives the friction plate to apply positive pressure to the friction ring through the loading bottom plate; The fulcrum frame is fixedly mounted on the top of the swing bracket, and the upper slide rail is pressed onto the top of the swing bracket; The top end of the guide force component frame is fixedly mounted on the end of the upper slide rail and is an inverted U-shaped structure, with guide grooves and fixed pulleys for guiding the loading ropes being arranged on both sides; The central axis of the lever and the axis of the main shaft are located in the same vertical plane, and the central axis of the upper slide rail and the central axis of the lever are arranged in parallel; the lever is arranged in parallel with the main shaft, and the middle part is swingably mounted on the top of the fulcrum frame through a hinge seat, one end is hinged with a hanging seat through a rotating shaft, and the other end is connected to the guide rope; the swing axis of the lever is parallel to the longitudinal axis; the top end of the hanging seat can swing around the axis of the rotating shaft, and the axis of the rotating shaft is parallel to the longitudinal axis and located in the same vertical plane; a roller is installed at the bottom end of the hanging seat, and the axis of the roller is parallel to the axis of the main shaft and located in the same vertical plane; The loading rope is a closed loop structure, with the top suspended on the roller, the bottom sleeved on the outer peripheral side of the loading base plate, and the middle portion guided by the guide groove and fixed pulley of the guide force component frame, and the fixed pulleys on both sides of the loading base plate; The bottom end of the guide rope passes around the guide seat and is connected to the weight; The guide seat is fixedly mounted on the base and located at the bottom of the lever, and is internally provided with two fixed pulleys rotating around a horizontal axis for controlling the middle portion of the guide rope to extend in a horizontal direction through the two fixed pulleys.

4. The test method according to claim 3, characterized in that: The detection device also includes a sensor support and a friction sensor; The sensor support is fixedly mounted on the base; The friction force sensor is fixedly mounted on the top of the sensor support and connected to the swing bracket to detect the friction force transmitted by the swing bracket.

5. The test method according to claim 4, characterized in that: The friction and wear testing machine also includes a display device connected to the control device by signal and a speed sensor installed on the motor; According to the signal obtained by the control device, the display device is used to display the working status information of the motor, the values ​​collected by the friction sensor and the positive pressure sensor; The speed sensor is connected to the control device by signal and is used to detect the speed of the motor; The motor is fixedly mounted on the bottom of the base, and a rubber gasket is sandwiched between the motor and the base; The base is provided with a notch for the transmission belt to pass through.

6. The test method according to any one of claims 1 to 5, characterized in that: The end surface of the main shaft is provided with a threaded hole; the friction ring is mounted on the main shaft through a first locking bolt; The friction plate is provided with a central through hole and is mounted on the lubricating oil groove via a second locking bolt passing through the central through hole; the friction plate can be reused by rotating.

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