A Line Contact Friction and Wear Testing Machine with Automatic Loading Function

Abstract

The present invention discloses a line contact friction and wear testing machine with automatic loading function, including a base, a main shaft, a driving transmission mechanism, a line contact friction pair, an automatic loading mechanism, a lubricating oil tank, a detection mechanism and a control mechanism; the lubricating oil tank can swing around the axis and longitudinal axis of the main shaft; the friction plate is detachably mounted on the inner bottom surface of the lubricating oil tank; the detection mechanism is used to detect the positive pressure and friction between the friction plate and the friction ring; the control mechanism is connected with the driving transmission mechanism, the detection mechanism, and the automatic loading mechanism signal, and is used to control the driving transmission mechanism to achieve the preset speed of the main shaft, and according to the preset loading force and the positive pressure signal detected by the detection mechanism, control the automatic loading mechanism so that the positive pressure between the friction plate and the friction ring reaches the preset loading force. The above-mentioned testing machine can ensure the constant line contact friction of the friction pair, realize accurate loading, and ensure continuous and stable lubrication.

Description

Technical Field

[0001] The invention relates to the technical field of friction testing, and in particular to a line contact friction and wear testing machine with an automatic loading function. Background Art

[0002] As we all know, when two objects are in contact with each other and there is relative motion between the contact surfaces, friction will occur between the two, which will lead to different degrees of friction and wear. This friction and wear phenomenon has both benefits and disadvantages. In industrial production, it can be used to improve the surface roughness of objects, but it may also greatly weaken the performance and service life of production machines. 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 the friction pair 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 the friction pair. Therefore, it is necessary to obtain the friction coefficient, wear characteristics, etc. between the corresponding materials by designing a suitable friction and wear machine.

[0004] In the prior art, the friction and wear testing machine used for line contact friction and wear testing has the problem that the line contact friction pairs cannot accurately maintain balance and stable line contact, because the vibration is inevitably generated during the rotation of the main shaft and the friction sensor measurement process will destroy the contact state between the friction pairs. This problem may cause uneven load loading and inaccurate results. In addition, some studies need to consider the friction characteristics of the friction pairs under stable lubrication conditions, but most friction and wear machines often cannot provide a continuous and stable lubrication environment. Summary of the invention

[0005] In view of this, the present invention provides a line contact friction and wear testing machine with automatic loading function, which can ensure the constant line contact friction of the friction pair by releasing the degree of freedom, and can ensure a continuous and stable lubrication environment, thereby improving the accuracy of the results.

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

[0007] A line contact friction and wear testing machine with automatic loading function, the friction and wear testing machine comprising:

[0008] Base;

[0009] A main shaft is supported on the top of the base in a horizontal direction;

[0010] A driving transmission mechanism, fixedly mounted on the base, for driving the main shaft to rotate;

[0011] A line contact friction pair, comprising a friction ring concentrically mounted on the end of the main shaft and a friction plate whose surface forms a constant line contact friction with the outer peripheral surface of the friction ring;

[0012] an automatic loading mechanism, mounted on the base and the spindle, for applying positive pressure to the friction plate;

[0013] A lubricating oil tank is installed on the automatic loading mechanism, has an opening on the top, can swing around the axis of the main shaft and the longitudinal axis, and is used to contain lubricating oil; the axis of the main shaft and the longitudinal axis intersect vertically in a horizontal plane; the friction plate is detachably installed on the inner bottom surface of the lubricating oil tank;

[0014] A detection mechanism, used for detecting the normal pressure and friction force between the friction plate and the friction ring;

[0015] A control mechanism is connected to the drive transmission mechanism, the detection mechanism, and the automatic loading mechanism by signal, and is used to control the drive transmission mechanism to achieve a preset rotational speed of the main shaft, and to control the automatic loading mechanism so that the positive pressure between the friction plate and the friction ring reaches a preset loading force based on a preset loading force and a positive pressure signal detected by the detection mechanism.

[0016] Furthermore, the driving transmission mechanism includes a driving motor, a transmission mechanism, a sleeve, a support plate and an accessory frame;

[0017] The driving motor is fixedly mounted on the base and is connected to the main shaft through the transmission mechanism;

[0018] The shaft sleeve is fixedly mounted on the base through the support plate;

[0019] 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 drive motor;

[0020] The accessory frame 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 automatic loading mechanism; the accessory frame is a hollow block structure, and has at least four side surfaces evenly distributed along the circumferential direction;

[0021] The control mechanism is connected to the drive motor signal and is used to control the drive motor and obtain the working state information of the drive motor.

[0022] Furthermore, the automatic loading mechanism 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 spring, a nut, a screw, a torque motor, a speed reducer and a loading rope;

[0023] The two adjustable outer rails are symmetrically distributed on both sides of the accessory frame 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;

[0024] 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;

[0025] Sliding guide rails extending in the vertical direction are arranged at the four inner corners of the loading outer frame;

[0026] 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;

[0027] The detection mechanism 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 loading platform;

[0028] The lubricating oil tank is fixedly installed on the top of the loading platform;

[0029] The automatic loading mechanism drives the friction plate to apply positive pressure to the friction ring through the loading bottom plate;

[0030] The fulcrum frame is fixedly mounted on the top of the accessory frame, and the upper slide rail is pressed onto the top of the accessory frame;

[0031] 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;

[0032] 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 top of the spring; the swing axis of the lever is parallel to the longitudinal axis; the top 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;

[0033] 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;

[0034] The bottom end of the spring is fixedly connected to the nut; the nut is spirally matched with the screw; the axis of the screw is arranged along the vertical direction;

[0035] The torque motor and the reducer are both fixedly mounted on the top surface of the base, and the torque motor and the screw are transmitted through the reducer;

[0036] The torque motor is signal-connected to the control mechanism.

[0037] Furthermore, the detection mechanism also includes a sensor support and a friction sensor;

[0038] The sensor support is fixedly mounted on the base;

[0039] The friction force sensor is fixedly mounted on the top of the sensor support and connected to the accessory frame for detecting the friction force transmitted by the accessory frame.

[0040] Furthermore, it also includes a display device connected to the control mechanism signal;

[0041] According to the signal acquired by the control mechanism, the display device is used to display the working status information of the drive motor, the working status information of the torque motor, and the values ​​collected by the friction sensor and the positive pressure sensor.

[0042] Furthermore, the transmission mechanism is a belt transmission mechanism, a gear transmission mechanism and a chain transmission mechanism;

[0043] The reducer is a bevel gear reducer or a worm gear reducer.

[0044] Furthermore, the end surface of the main shaft is provided with a threaded hole;

[0045] The friction ring is mounted on the main shaft through a first locking bolt.

[0046] Furthermore, the friction plate is an annular plate provided with a central through hole, and is mounted on the lubricating oil groove by a second locking bolt passing through the central through hole;

[0047] The friction plate can be reused by rotating.

[0048] Furthermore, it also includes a speed sensor installed on the drive motor;

[0049] The rotation speed sensor is connected to the control mechanism signal and is used to detect the rotation speed of the drive motor.

[0050] Furthermore, the driving motor is fixedly mounted on the bottom of the base, and a rubber gasket is sandwiched between the driving motor and the base;

[0051] The base is provided with a notch for the transmission mechanism to pass through.

[0052] Beneficial effects:

[0053] (1) The line contact friction and wear testing machine of the present invention supports a main shaft and a driving transmission mechanism for driving the main shaft to rotate on a base. The line contact friction pair includes a friction ring installed concentrically at the end of the main shaft and a friction plate installed in a lubricating oil groove. The driving transmission mechanism drives the main shaft to rotate, and drives the friction ring to rotate through the main shaft, so that the friction ring and the friction plate perform line contact friction; the automatic loading mechanism is used to apply positive pressure to the friction plate, and friction tests under different pressure conditions are realized through the automatic loading mechanism; the lubricating oil groove can ensure a continuous and stable lubrication environment for the line contact friction pair, and the friction plate always maintains a constant line contact friction state with the friction ring through the swing of the lubricating oil groove around the axis center line and the longitudinal axis of the main shaft that intersect vertically in the horizontal plane, and the friction ring and the friction plate always have good lubrication conditions through the lubricating oil groove; the detection mechanism is used to detect the positive pressure and friction force between the friction plate and the friction ring; the control The mechanism realizes the preset rotation speed of the main shaft by controlling the driving transmission mechanism, and controls the automatic loading mechanism to load according to the preset loading force, and realizes real-time feedback adjustment through the detection of the positive pressure by the detection mechanism, so as to realize automatic and accurate loading; therefore, when the above-mentioned line contact friction and wear testing machine performs the friction and wear test, the constant line contact of the line contact friction pair can be ensured by releasing the degree of freedom, so as to avoid the defect that the point contact is formed when there is an angle between the outer surface of the existing friction ring and the friction plate, and the stable line contact condition cannot be achieved; when the automatic loading mechanism has the degree of freedom of swinging, the loading force of the friction plate and the reaction force of the friction ring will form a restoring torque, so that the automatic loading mechanism swings in the direction of reducing the angle, and the friction plate will get close to the friction ring until the friction pair reaches a stable line contact, and accurate loading can be realized through feedback adjustment, so as to improve the accuracy of the friction and wear test.

[0054] (2) In the line contact friction and wear testing machine of the present invention, the shaft sleeve of the driving transmission mechanism is fixedly installed on the base through the support plate, and the main shaft is installed in the shaft sleeve through the bearing. The rotational installation of the main shaft is realized by the shaft sleeve and the support plate. Since the accessory frame is a hollow block structure, it can be swingably installed on one end of the shaft sleeve close to the friction ring, so that the automatic loading mechanism has the freedom of swinging around the axis of the main shaft, so that the automatic loading mechanism can swing with the friction plate under the friction force between the friction plate and the friction ring, thereby avoiding the deformation of the sensitive element of the friction 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 measurement process, ensuring that the positive pressure is always perpendicular to the contact surface during the friction measurement process, and improving the accuracy and repeatability of the test results.

[0055] (3) The line contact friction and wear testing machine of the present invention has an automatic loading mechanism composed of 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 spring, a nut, a screw, a torque motor, a reducer and a loading rope, which ensures that the automatic loading mechanism can swing synchronously with the accessory frame around the axis 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 line contact friction pair and the automatic loading mechanism move synchronously, so that the force applied by the automatic loading mechanism just passes through the friction contact position between the friction ring and the friction plate, further improving the accuracy of the test results; at the same time, a spring is used at the end of the lever for loading, and the spring can buffer the loading between the lever and the nut; the torque motor is controlled by the control mechanism for loading, and combined with the positive pressure feedback of the detection mechanism, the load applied by the torque motor to the lever can be accurately controlled, which is conducive to improving the accuracy of the test results.

[0056] (4) Since the detection mechanism includes a friction sensor and a positive pressure sensor, the friction sensor is fixedly installed between the sensor support and the accessory frame, and the positive pressure sensor is fixedly installed on the top surface of the loading base plate, the friction force between the friction ring and the friction plate can be detected by the friction sensor, and at the same time, the positive pressure applied between the friction ring and the friction plate by the automatic loading mechanism can be detected in real time by the positive pressure sensor.

[0057] (5) In the line contact friction and wear testing machine of the present invention, since the friction plate is an annular plate provided with a central through hole and is installed in the lubricating oil tank by means of a second locking bolt passing through the central through hole, after a single friction and wear test is completed, the friction plate can be rotated around the axis of its central through hole 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, so that the friction plate can be repeatedly used by rotation, which can greatly improve the utilization rate of the test materials and reduce unnecessary waste.

[0058] (6) Since a rubber gasket is sandwiched between the drive motor and the base, the vibration of the drive motor can be isolated by the rubber gasket, thereby reducing the test error caused by the vibration of the drive motor itself when it is working. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 It is a three-dimensional structural schematic diagram of the line contact friction and wear testing machine of the present invention;

[0060] Figure 2 for Figure 1 Schematic diagram of the exploded structure of the centerline contact friction and wear testing machine.

[0061] Among them, 1-base, 2-main support plate, 3-auxiliary support plate, 4-drive motor, 5-transmission belt, 6-spindle, 7-accessory frame, 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-spring, 16-nut, 17-screw, 18-torque motor, 19-reducer, 20-lubricating oil groove, 21-friction ring, 22-friction plate, 23-sensor support, 24-friction force sensor, 25-positive pressure sensor, 26-first locking bolt, 27-second locking bolt, 28-sleeve, 29-guide groove, 30-fixed pulley, 31-articulated seat, 32-rotating shaft, 33-lifting seat, 34-roller, 35-upper slide rail, 36-loading rope DETAILED DESCRIPTION

[0062] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0063] The embodiment of the present invention provides a line contact friction and wear testing machine with automatic loading function, such as Figure 1 and Figure 2 As shown in the structure, the line contact friction and wear testing machine includes a base 1, a main shaft 6, a driving transmission mechanism, a line contact friction pair, an automatic loading mechanism, a lubricating oil tank 20, a detection mechanism and a control mechanism; the base 1 is the basis of the line contact friction and wear testing machine and can be made of a steel plate; for the convenience of description, in the embodiment of the present invention, the base 1 is the base ... Figure 1 The direction from left to right on the page is defined as the horizontal direction, which is the axis of the main axis. Figure 1 The direction from top to bottom of the page is defined as the vertical direction, perpendicular to the Figure 1 The direction of the page is defined as the longitudinal direction, which is the extension direction of the longitudinal axis.

[0064] The main shaft 6 is arranged in the horizontal direction and supported on the top of the base 1 so as to be rotatable around the axis; the axial direction and the lateral direction of the main shaft 6 coincide with each other;

[0065] The driving transmission mechanism is fixedly mounted on the base 1, and is used to drive the main shaft 6 to rotate, and provide power for the rotation of the main shaft 6; the driving transmission mechanism can control and adjust the rotation speed of the main shaft 6, so as to control the rotation speed of the friction ring 21 rotating with the main shaft 6;

[0066] The line contact friction pair comprises a friction ring 21 concentrically mounted on the end of the main shaft 6 and a friction plate 22 whose surface forms a constant line contact friction with the outer peripheral surface of the friction ring 21; the friction ring 21 is concentrically arranged with the main shaft 6 and detachably mounted on the end of the main shaft 6; a constant line contact friction is formed between the outer peripheral surface of the friction ring 21 and the surface of the friction plate 22; a threaded hole is arranged on the end surface of the main shaft 6; the friction ring 21 is mounted on the main shaft 6 through a first locking bolt 26; the end surface of the friction ring 21 is arranged parallel to the end surface of the main shaft 6;

[0067] The automatic loading mechanism is installed on the base 1 and the main shaft 6, and is used to apply positive pressure to the friction plate 22, so that there is positive pressure between the friction plate 22 and the friction ring 21; the automatic loading mechanism can automatically load according to the preset loading force, which has the advantages of accurate loading and labor saving;

[0068] The lubricating oil groove 20 is installed on the automatic loading mechanism, and an opening is provided on the top, which can swing around the axis and longitudinal axis of the main shaft 6, and is used to contain lubricating oil to lubricate the friction parts of the friction plate 22 and the friction ring 21; 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; the friction plate 22 is detachably installed on the inner bottom surface of the lubricating oil groove 20; the friction plate 22 is an annular plate provided with a central through hole, and the upper surface of the bottom plate of the lubricating oil groove 20 can be provided with a threaded hole (not shown in the figure), and is installed in the lubricating oil groove 20 by threading the second locking bolt 27 penetrated through the central through hole and the threaded hole on the upper surface of the bottom plate; the friction plate 22 can be repeatedly used by rotating; when conducting a friction and wear test, the lubricating oil groove 20 can contain lubricating oil;

[0069] The detection mechanism is used to detect the normal pressure and friction force between the friction plate 22 and the friction ring 21;

[0070] The control mechanism is connected to the drive transmission mechanism, the detection mechanism and the automatic loading mechanism by signal, and is used to control the drive transmission mechanism to achieve the preset speed of the main shaft 6, and control the automatic loading mechanism to make the positive pressure between the friction plate 22 and the friction ring 21 reach the preset loading force according to the preset loading force and the positive pressure signal detected by the detection mechanism. The preset loading force can be pre-stored in the control mechanism, or input into the control mechanism during the test.

[0071] The above-mentioned line contact friction and wear testing machine supports a main shaft 6 and a driving transmission mechanism for driving the main shaft 6 to rotate on the base 1. The line contact friction pair includes a friction ring 21 concentrically installed at the end of the main shaft 6 and a friction plate 22 installed in the lubricating oil groove 20. The driving transmission mechanism drives the main shaft 6 to rotate, and drives the friction ring 21 to rotate through the main shaft 6, so that the friction ring 21 and the friction plate 22 are in line contact friction; the automatic loading mechanism is used to apply positive pressure to the friction plate 22 and the friction ring 21. The automatic loading mechanism can automatically apply a predetermined positive pressure between the friction ring 21 and the friction plate 22 to achieve friction tests under different pressure conditions; the lubricating oil groove 20 can ensure a continuous and stable lubrication environment for the line contact friction pair. The lubricating oil groove 20 can swing around the axis of the main shaft 6 and around the longitudinal axis, so that the friction plate 22 always maintains a constant line contact friction state with the friction ring 21, and the lubricating oil groove 20 can make the friction ring 21 and the friction plate 22 always have good lubrication conditions; the detection mechanism is used to detect the friction The positive pressure and friction force between the wiper plate 22 and the friction ring 21; the control mechanism realizes the preset speed of the main shaft 6 by controlling the driving transmission mechanism, and controls the automatic loading mechanism to load according to the preset loading force, and realizes real-time feedback adjustment through the detection of the positive pressure by the detection mechanism, so as to realize automatic and accurate loading; therefore, when the above-mentioned line contact friction and wear testing machine is conducting a friction and wear test, the constant line contact of the line contact friction pair can be ensured by releasing the degree of freedom, avoiding the defect that the outer surface of the existing friction ring 21 and the friction plate 22 form point contact due to the existence of a gap and cannot reach a stable line contact condition; when the automatic loading mechanism has a swinging degree of freedom, the loading force of the friction plate 22 and the reaction force of the friction ring 21 will form a restoring torque, so that the automatic loading mechanism swings in the direction of reducing the angle, and the friction plate 22 will get close to the friction ring 21 until the friction pair reaches a stable line contact, and accurate loading can be realized through feedback adjustment, thereby improving the accuracy of the friction and wear test.

[0072] The friction plate 22 of the above-mentioned line contact friction and wear testing machine is an annular plate provided with a central through hole, and is installed in the lubricating oil groove 20 by a second locking bolt 27 penetrated through the central through hole. Therefore, after a single friction and wear test is completed, the friction plate 22 can be rotated around the axis of its central through hole and then fixed, and the surface portion of the friction plate 22 that does not participate in the friction is used as the friction pair contact surface of the next test, so that the friction plate 22 can be repeatedly used by rotation, which can greatly improve the utilization rate of the test material and reduce unnecessary waste.

[0073] In a specific implementation manner, Figure 1 and Figure 2 As shown in the structure, the drive transmission mechanism includes a drive motor 4, a transmission mechanism, a sleeve 28, a support plate and an accessory frame 7;

[0074] The driving motor 4 is fixedly mounted on the base 1, and is connected to the main shaft 6 through a transmission mechanism, so as to drive the main shaft 6 to rotate; the driving motor 4 can be fixedly mounted on the bottom of the base 1 by bolts, and a rubber gasket (not shown in the figure) is sandwiched between the driving motor 4 and the base 1; the base 1 is provided with a notch for the transmission mechanism to pass through; the transmission mechanism can be a belt transmission mechanism, a gear transmission mechanism or a chain transmission mechanism;

[0075] The shaft sleeve 28 is fixedly mounted on the base 1 through a support plate; Figure 1 and Figure 2 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 frame structure with high rigidity to provide effective support for the main shaft 6; the main shaft 6 is installed in the sleeve 28 through a bearing, and the axis of the main shaft 6 is arranged parallel to the axis of the drive motor 4; the accessory frame 7 can be installed on the end of the sleeve 28 close to the friction ring 21 and can swing around the axis of the main shaft 6, which is used to support the automatic loading mechanism and enable the automatic loading mechanism to have a degree of freedom of rotation around the axis of the main shaft 6; the accessory frame 7 is a hollow block structure and has at least four side surfaces evenly distributed along the circumferential direction; the accessory frame 7 is provided with a bearing through hole, and a bearing is installed in the bearing through hole, which is arranged on the outer peripheral side of the sleeve 28 through the bearing sleeve, and the accessory frame 7 is rotated relative to the sleeve 28 through the bearing; the rotation axis of the accessory frame 7 coincides with the axis of the main shaft 6; the control mechanism is connected to the drive motor 4 signal to control the drive motor 4 and obtain the working status information of the drive motor 4.

[0076] Since the shaft sleeve of the driving transmission mechanism is fixedly installed on the base 1 through the support plate, the main shaft 6 is installed in the shaft sleeve 28 through the bearing, and the rotation installation of the main shaft 6 is realized by the shaft sleeve 28 and the support plate; since the accessory frame 7 is a hollow block structure, it can be swingably installed on one end of the shaft sleeve 28, so that the automatic loading mechanism has the freedom of swinging around the axis of the main shaft 6, so that the automatic loading mechanism can swing with the friction plate 22 under the friction force between the friction plate 22 and the friction ring 19, thereby avoiding the deformation of the sensitive element of the friction sensor causing the friction plate 22 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 24 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 accuracy and repeatability of the test results.

[0077] Since a rubber gasket is sandwiched between the driving motor 4 and the base 1 , the vibration of the driving motor 4 can be isolated by the rubber gasket, thereby reducing the test error caused by the vibration of the driving motor 4 itself when working.

[0078] Furthermore, the automatic loading mechanism 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 35, a fulcrum frame 13, a lever 14, a spring 15, a nut 16, a screw 17, a torque motor 18, a speed reducer 19 and a loading rope 36;

[0079] The two adjustable outer rails 8 are symmetrically distributed on both sides of the accessory frame 7 and can slide along the axial direction of the main shaft 6. The central axis of the adjustable outer rails 8 is parallel to the axis of the main shaft 6 and has the same height; Figure 1 and Figure 2 As shown in the structure, a fixed slider is fixedly installed on the surface of one side of the accessory frame 7 corresponding to 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 accessory frame 7; the fixed slider and the accessory frame 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;

[0080] 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 20, that is, at one end of the adjustable outer rail 8 away from the accessory frame 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 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 and the mounting hole; a bearing can also be installed between the rotating shaft 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 automatic loading mechanism along the longitudinal axis can be released;

[0081] The four inner corners of the loading outer frame 9 are provided with sliding guide rails extending in the vertical direction and parallel to each other; the loading outer frame 9 is a frame structure, and four vertical sliding guide rails are provided inside the frame structure for guiding the movement direction of the loading base plate 10 and the loading platform 11;

[0082] 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 slidably matched with the inner side surface of the sliding guide rail; fixed pulleys that roll with the loading rope 36 are symmetrically arranged on both sides of the loading base plate 10;

[0083] The detection mechanism includes a positive pressure sensor 25 fixedly mounted on the top surface of the loading base plate 10; the positive pressure sensor 25 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, so as to measure the positive pressure between the friction plate 22 and the friction ring 21;

[0084] The lubricating oil tank 20 is fixedly mounted on the top of the loading platform 11;

[0085] The automatic loading mechanism drives the friction plate 22 to apply positive pressure to the friction ring 21 through the loading base plate 10;

[0086] The fulcrum frame 13 is fixedly mounted on the top of the accessory frame 7, and the upper slide rail 35 is pressed against the top of the accessory frame 7; the fulcrum frame 13 may be an H-shaped structure;

[0087] The top of the guide force component frame 12 is fixedly mounted on the end of the upper slide rail 35, and is an inverted U-shaped structure, with guide grooves 29 and fixed pulleys 30 for guiding the loading rope 36 provided on both sides thereof, for guiding the loading rope 36;

[0088] The lever 14 is arranged parallel to 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 the top of the spring 15; the swing axis of the lever 14 is parallel to the longitudinal axis; the top 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 is located in the same vertical plane; the bottom end of the hanging seat 33 is installed with a roller 34 arranged parallel to the main shaft 6, and the axis of the roller 34 is parallel to the axis of the main shaft 6 and is located in the same vertical plane;

[0089] The loading rope 36 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 part guided by the guide groove 29 and the fixed pulley 30 of the guide force component frame 12, and the fixed pulleys 30 on both sides of the loading base plate 10; during the loading process, the loading rope 36 is in a taut state, and the loading force generated by the lever 14 can be transmitted to the loading base plate 10; Figure 1 and Figure 2 As shown in the structure, when two loading ropes 36 are used, the two loading ropes 36 have the same length;

[0090] The bottom end of the spring 15 is fixedly connected to the nut 16, which can be made of a steel plate with a central threaded hole; the nut 16 is spirally matched with the screw 17, and the axis of the screw 17 is arranged along the vertical direction; thereby, the rotational motion of the screw 17 is converted into a linear reciprocating motion along the vertical direction, thereby pulling the lever 14 to swing and realize loading;

[0091] The torque motor 18 and the reducer 19 are both fixedly mounted on the top surface of the base 1, and the torque motor 18 and the screw 17 are transmitted through the reducer 19; the torque motor 18 is connected to the control mechanism signal. The reducer 19 can be a bevel gear reducer or a worm gear reducer.

[0092] The automatic loading mechanism of the above-mentioned line contact friction and wear tester is composed of 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 35, a fulcrum frame 13, a lever 14, a spring 15, a nut 16, a screw 17, a torque motor 18, a reducer 19 and a loading rope 36, which ensures that the automatic loading mechanism can swing synchronously with the accessory frame 7 around the axis 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 line contact friction pair and the automatic loading mechanism move synchronously, so that the force applied by the automatic loading mechanism just passes through the friction contact position between the friction ring 21 and the friction plate 22, further improving the accuracy of the test results. At the same time, a spring 15 is used at the end of the lever 14 for loading, and the spring 15 can buffer the loading between the lever 14 and the nut 16; the torque motor 18 is controlled by the control mechanism to load, and combined with the positive pressure feedback of the detection mechanism, the load applied by the torque motor 18 to the lever can be accurately controlled, which is conducive to improving the accuracy of the test results.

[0093] Specifically, the detection mechanism also includes a sensor support 23 and a friction sensor 24; the sensor support 23 is fixedly mounted on the base 1; the sensor support 23 can be an L-shaped structure, with a small hole for mounting the friction sensor 24 on the top; the friction sensor 24 is fixedly mounted on the top of the sensor support 23 and connected to the accessory frame 7 to detect the friction transmitted by the accessory frame 7; the friction sensor 24 can be connected to the accessory frame 7 through a T-shaped plate, and when the accessory frame 7 is subjected to the friction transmitted by the friction plate 22, the friction sensor 24 Due to the tensile force, a corresponding deformation signal will be generated; the positive pressure sensor 25 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 25 contacts the loading platform 11; when the loading process is completed, the positive pressure sensor 25 is squeezed and deformed accordingly by the loading force, and a deformation signal is generated; the control mechanism is connected to the friction force sensor 24 and the positive pressure sensor 25 signal.

[0094] Since the detection mechanism includes a friction sensor 24 and a positive pressure sensor 25, the friction sensor 24 is fixedly installed between the sensor support 23 and the accessory frame 7, and the positive pressure sensor 25 is fixedly installed on the top surface of the loading base plate 10. Therefore, the friction force between the friction ring 21 and the friction plate 22 can be detected by the friction sensor 24, and at the same time, the positive pressure sensor 25 can detect the positive pressure applied between the friction ring 21 and the friction plate 22 by the automatic loading mechanism.

[0095] On the basis of the above various embodiments, the above-mentioned line contact friction and wear testing machine further includes a display device connected to the control mechanism signal and a speed sensor installed on the drive motor 4; the display device and the control mechanism can be an integral structure; according to the signal obtained by the control mechanism, the display device is used to display the working state information of the drive motor 4, the working state information of the torque motor 18, and the values ​​collected by the friction sensor 24 and the positive pressure sensor 25. The speed sensor is connected to the control mechanism signal and is used to detect the speed of the drive motor 4.

[0096] The display device can be used to conveniently display various working parameters and collected parameters of the test machine; the speed sensor can be used to conveniently detect the speed of the drive motor 4, and the speed sensor and the control mechanism can monitor and adjust the relative speed between the friction plate 22 and the friction ring 21.

[0097] During the test using the above-mentioned line contact friction and wear tester, the torque motor 18 is connected to the control mechanism by electrical signals, receives the preset loading force signal of the control mechanism, and applies external force to the lever 14 through the torque motor 18. At the same time, the positive pressure sensor obtains the loading force in real time and feeds it back to the control mechanism. The control mechanism compares the loading force with the preset loading force, and outputs a correction signal to the torque motor 18 in real time to complete the feedback control process of the loading force. The loading force is transmitted to the loading base plate 10 through the loading rope 36. The loading base plate 10 moves upward along the sliding guide rail due to the slide rail restriction of the loading outer frame 9. The positive pressure sensor 25 moves with the loading base plate 10, and then contacts and pushes the loading platform 11 to move upward. The lubricating oil tank 20 is fixed on the loading platform 11 and moves upward with the loading platform 11. Since the friction plate 22 is located at the inner bottom of the lubricating oil groove 20, the friction plate 22 moves upward with the lubricating oil groove 20. After the end face of the friction plate 22 is tangent to and completely fits with the outer peripheral surface of the friction ring 21, 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 line contact state, and the loading process is completed.

[0098] When the outer surface of the friction ring 21 or the friction plate 22 is not tangent to the end surface of the friction plate 22 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 21 is a fixed structure, the rotation torque finally acts on the automatic loading mechanism, causing the loading outer frame 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 22 swings accordingly with the loading outer frame; when the outer surface of the friction ring 21 and the end surface of the friction plate 22 are tangent again, the rotation torque acting between the two planes disappears, and the friction pair resumes the line contact state. When the drive motor 4 is running, the friction ring 21 rotates with the main shaft 6, and the outer surface of the friction ring 21 and the end surface of the friction plate 22 are always tangent under the action of the above-mentioned restoring torque, so that the friction ring 21 and the friction plate 22 are always in a stable line contact state.

[0099] The above-mentioned line contact friction and wear tester can realize the constant line contact friction between the friction ring 21 and the friction plate 22. On this basis, the rotation speed of the friction ring 21 is controlled by adjusting the rotation speed of the drive motor 4, and the size of the positive pressure is controlled by controlling the rotation angle of the torque motor 18 in the automatic loading mechanism, thereby realizing the detection of the friction and wear conditions of the line contact friction pair under different rotation speeds and different positive pressure conditions, and improving the accuracy of the test results. Before loading the end of the lever by the rotation angle of the torque motor 18, the torque motor 18 can be calibrated in advance to obtain the corresponding relationship between the rotation angle of the torque motor 18 and the positive pressure value, and then the rotation angle of the torque motor 18 is controlled according to the corresponding relationship to realize accurate loading of the positive pressure.

[0100] 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 line contact friction and wear testing machine with automatic loading function, characterized in that: include: Base; A main shaft is supported on the top of the base in a horizontal direction; A driving transmission mechanism, fixedly mounted on the base, for driving the main shaft to rotate; A line contact friction pair, comprising a friction ring concentrically mounted on the end of the main shaft and a friction plate whose surface forms a constant line contact friction with the outer peripheral surface of the friction ring; an automatic loading mechanism, mounted on the base and the spindle, for applying positive pressure to the friction plate; A lubricating oil groove is installed on the loading mechanism, has an opening on the top, can swing around the axis of the main shaft and the longitudinal axis, and is used to contain lubricating oil; the axis of the main shaft and the longitudinal axis intersect vertically in a horizontal plane; the friction plate is detachably installed on the inner bottom surface of the lubricating oil groove; When the line contact friction and wear testing machine is conducting a friction and wear test, the line contact friction pair can be ensured to be in a constant line contact state by releasing the degree of freedom, thereby avoiding the defect that a point contact is formed when there is an angle between the outer surface of the existing friction ring and the friction plate, and a stable line contact condition cannot be achieved; when the automatic loading mechanism has a swinging degree of freedom, the loading force of the friction plate and the reaction force of the friction ring will form a restoring torque, so that the automatic loading mechanism swings in a direction of reducing the angle, and the friction plate will get closer to the friction ring until the friction pair reaches a stable line contact; A detection mechanism, used for detecting the normal pressure and friction force between the friction plate and the friction ring; A control mechanism is connected to the drive transmission mechanism, the detection mechanism, and the automatic loading mechanism by signal, and is used to control the drive transmission mechanism to achieve a preset rotational speed of the main shaft, and to control the automatic loading mechanism so that the positive pressure between the friction plate and the friction ring reaches a preset loading force based on a preset loading force and a positive pressure signal detected by the detection mechanism.

2. The line contact friction and wear testing machine according to claim 1, characterized in that: The driving transmission mechanism includes a driving motor, a transmission mechanism, a sleeve, a support plate and an accessory frame; The driving motor is fixedly mounted on the base and is connected to the main shaft through the transmission mechanism; 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 drive motor; The accessory frame 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 mechanism; the accessory frame is a hollow block structure, and has at least four side surfaces evenly distributed along the circumferential direction; The control mechanism is connected to the drive motor signal and is used to control the drive motor and obtain the working state information of the drive motor.

3. The line contact friction and wear testing machine according to claim 2, characterized in that: The loading mechanism 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 spring, a nut, a screw, a torque motor, a reducer and a loading rope; The two adjustable outer rails are symmetrically distributed on both sides of the accessory frame 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 mechanism 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 loading platform; The lubricating oil tank is fixedly installed on the top of the loading platform; The loading mechanism 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 accessory frame, and the upper slide rail is pressed onto the top of the accessory frame; 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 top of the spring; the swing axis of the lever is parallel to the longitudinal axis; the top 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 spring is fixedly connected to the nut; the nut is spirally matched with the screw; the axis of the screw is arranged along the vertical direction; The torque motor and the reducer are both fixedly mounted on the top surface of the base, and the torque motor and the screw are transmitted through the reducer; The torque motor is signal-connected to the control mechanism.

4. The line contact friction and wear testing machine according to claim 3, characterized in that: The detection mechanism 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 accessory frame for detecting the friction force transmitted by the accessory frame.

5. The line contact friction and wear testing machine according to claim 4, characterized in that: It also includes a display device connected to the control mechanism signal; according to the signal obtained by the control mechanism, the display device is used to display the working status information of the drive motor, the working status information of the torque motor, and the values ​​collected by the friction sensor and the positive pressure sensor.

6. The line contact friction and wear testing machine according to claim 3, characterized in that: The transmission mechanism is a belt transmission mechanism, a gear transmission mechanism or a chain transmission mechanism; The reducer is a bevel gear reducer or a worm gear reducer.

7. The line contact friction and wear testing machine 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.

8. The line contact friction and wear testing machine according to any one of claims 1 to 5, characterized in that: The friction plate is an annular plate provided with a central through hole, and is mounted on the lubricating oil groove by a second locking bolt passing through the central through hole; The friction plate can be reused by rotating.

9. The line contact friction and wear testing machine according to any one of claims 2 to 5, characterized in that: Also includes a speed sensor installed on the drive motor; The rotation speed sensor is connected to the control mechanism signal and is used to detect the rotation speed of the drive motor.

10. The line contact friction and wear testing machine according to any one of claims 2 to 5, characterized in that: The driving motor is fixedly mounted on the bottom of the base, and a rubber gasket is sandwiched between the driving motor and the base; The base is provided with a notch for the transmission mechanism to pass through.

Images