A Line Contact Friction and Wear Testing Machine with Calibration Function

Abstract

The present invention discloses a line contact friction and wear testing machine with calibration function, comprising: a base; a main shaft, supported on the top of the base in the horizontal direction; a driving device, fixedly mounted on the base; 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 friction ring; a loading device mounted on the base and the main shaft; a lubricating oil tank, capable of swinging around the axis and longitudinal axis of the main shaft; a detection device, used to detect the contact pressure and friction force of the line contact friction pair; a laser calibration device, the bottom end of which is mounted on the base, used to calibrate the initial position of the loading device by laser. The above-mentioned testing machine can ensure the constant line contact friction of the friction pair and can ensure continuous and stable lubrication. The loading device can be calibrated before the test starts, which improves 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 line contact friction and wear testing machine with a calibration 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 a calibration function, which can ensure the constant line contact friction of the friction pair by releasing the degree of freedom, can ensure a continuous and stable lubrication environment, and can calibrate the loading device before the test starts, thereby improving the accuracy of the test results.

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

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

[0008] Pedestal;

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

[0010] A driving device, 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] a loading device, mounted on the base and the main shaft, for pushing the friction plate toward the friction ring to adjust the normal pressure between the friction plate and the friction ring;

[0013] A lubricating oil tank is installed on the loading device, 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 device, used for detecting the normal pressure and friction force between the friction plate and the friction ring;

[0015] A control device, connected to the driving device and the detection device by signals, and used to obtain a detection signal from the detection device;

[0016] A laser calibration device, the bottom end of which is mounted on the base and located outside the loading device, is used to calibrate the initial position of the loading device by laser.

[0017] Furthermore, the laser calibration device includes three lasers and a laser fixing frame;

[0018] The laser fixture is a door-shaped bracket, comprising two vertical rods symmetrically arranged on both sides of the main axis and a cross rod fixedly connected to the top ends of the two vertical rods; the center line of the cross rod is arranged parallel to the longitudinal axis;

[0019] The bottom ends of the two vertical rods can be adjustably mounted on the top surface of the base along the axial position of the main shaft;

[0020] A laser is installed on each of the vertical rod and the horizontal rod;

[0021] The laser installed on the horizontal rod is used to emit a vertical laser beam toward the geometric center of the friction ring and propagating in the vertical direction; the laser installed on the vertical rod is used to emit a horizontal laser beam toward the geometric center of the friction ring and propagating in the horizontal direction;

[0022] The loading device is provided with light-transmitting holes for passing the vertical laser beam and the horizontal laser beam.

[0023] Furthermore, the driving device includes a motor, a transmission belt, a sleeve, a support plate and a rotating frame;

[0024] The motor is fixedly mounted on the base and is connected to the main shaft through the transmission belt;

[0025] The shaft sleeve is fixedly mounted on the base through the support plate;

[0026] 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;

[0027] The rotating frame is mounted on one end of the sleeve close to the friction ring so as to be able to swing around the axis of the main shaft, and is used to support the loading device; the rotating frame is a hollow block structure, and has at least four side surfaces evenly distributed along the circumferential direction;

[0028] The control device is connected to the motor signal and is used to control the motor and obtain the working status information of the motor.

[0029] 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;

[0030] The two adjustable outer rails are symmetrically distributed on both sides of the rotating 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;

[0031] 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;

[0032] Sliding guide rails extending in the vertical direction are arranged at the four inner corners of the loading outer frame;

[0033] 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;

[0034] 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;

[0035] The lubricating oil tank is fixedly installed on the top of the loading platform;

[0036] The loading device drives the friction plate to apply positive pressure to the friction ring through the loading bottom plate;

[0037] The fulcrum frame is fixedly installed on the top of the rotating frame, and the upper slide rail is pressed onto the top of the rotating frame;

[0038] The top center of the guide force component frame is fixedly installed 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 arranged on both sides;

[0039] 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;

[0040] The two loading ropes are parallel and both have a closed loop structure, with the tops suspended on the rollers and the bottoms sleeved on the outer peripheral side of the loading base plate, and the middle parts are guided by the guide grooves and fixed pulleys of the guide force component frame and the fixed pulleys on both sides of the loading base plate;

[0041] The bottom end of the guide rope passes around the guide seat and is connected to the weight;

[0042] The guide seat is fixedly mounted on the base and located at the bottom of the lever, and is provided with two fixed pulleys rotating around a horizontal axis, and is used to control the middle part of the guide rope to extend in the horizontal direction through the two fixed pulleys;

[0043] The vertical rod is located on the outside of the adjustable outer rail, and the horizontal rod is located on the top side of the lever;

[0044] The hanging seat, the rotating shaft, the roller, the upper slide rail, and the guide force component frame are all provided with light-transmitting holes penetrating in the vertical direction for transmitting the vertical laser beam;

[0045] The adjustable outer rail and the loading outer frame are both provided with light-transmitting holes penetrating along the longitudinal axis for transmitting the horizontal laser beam.

[0046] Furthermore, the detection device also includes a sensor support and a friction sensor;

[0047] The sensor support is fixedly mounted on the base;

[0048] The friction force sensor is fixedly mounted on the top of the sensor support and connected to the rotating frame, and is used to detect the friction force transmitted by the rotating frame.

[0049] Furthermore, it also includes a display device connected to the control device signal and a speed sensor installed on the motor;

[0050] 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;

[0051] The rotation speed sensor is signal-connected to the control device and is used to detect the rotation speed of the motor.

[0052] Furthermore, the end surface of the main shaft is provided with a threaded hole;

[0053] The friction ring is mounted on the main shaft via a first locking bolt;

[0054] 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;

[0055] The friction plate can be reused by rotating.

[0056] Furthermore, the motor is fixedly mounted on the bottom of the base, and a rubber gasket is sandwiched between the motor and the base;

[0057] The base is provided with a notch for the transmission belt to pass through.

[0058] Beneficial effects:

[0059] (1) The testing machine of the present invention supports a main shaft and a driving device for driving the main shaft to rotate on a base. The line contact friction pair includes a friction ring installed on the end of the main shaft and a friction plate installed in a lubricating oil groove. The friction ring is driven to rotate by the main shaft so that the friction ring and the friction plate are in line contact friction. The loading device is used to adjust the positive pressure between the friction plate and the friction ring, and the friction test under different pressure conditions is realized by the loading device. The lubricating oil groove can ensure a continuous and stable lubrication environment for the line contact friction pair, and the lubricating oil groove can swing around the axis of the main shaft and the longitudinal axis that intersect vertically in the horizontal plane, so that the friction plate and the friction ring can always maintain a constant line contact friction state, and the lubricating oil groove can ensure that the friction ring and the friction plate always have good lubrication conditions; the detection device is used to detect the positive pressure between the friction plate and the friction ring force and friction force; the laser calibration device is used to calibrate the initial position of the loading device through a laser, so that the positive pressure applied by the loading device just passes through the geometric center of the friction ring, so that the loading is accurate during the friction and wear test; 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 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 loading device 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 loading device swings in the 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, thereby improving the accuracy of the friction and wear test results.

[0060] (2) The testing machine of the present invention emits lasers to the geometric center of the friction ring through the three lasers of the laser calibration device, so that the laser beams emitted by the lasers located at the top and both sides of the loading device converge at the geometric center of the friction ring. A light-transmitting hole for transmitting the laser beam is provided on the loading device, so that the initial position of the loading device can be calibrated through the light-transmitting hole, thereby avoiding the phenomenon of deviation of the installation position of the loading device, making the loading of the loading device accurate, and further improving the accuracy of the friction and wear test.

[0061] (3) In the testing machine of the present invention, the shaft sleeve of the driving device is fixedly installed on the base through the support plate, and the main shaft is installed in the shaft sleeve through the bearing. The rotation installation of the main shaft is realized by the shaft sleeve and the support plate. Since the rotating frame is a hollow block structure, it can be swingably installed on one end of the shaft sleeve close to the friction ring to support the loading device. By swinging the rotating frame installed on the shaft sleeve, the loading device can have the freedom of swinging around the axis of the main shaft, so that the loading device can swing with the friction plate, 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, thereby 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.

[0062] (4) In the testing machine of the present invention, the loading device is 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 guide seat, a weight, a guide rope and a loading rope, and a light-transmitting hole is provided on the component corresponding to the optical path of the laser, thereby ensuring that the loading device can swing synchronously with the rotating frame around the axis of the main shaft, and the position of the loading device is calibrated by the laser beam emitted by the laser before the test, 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 loading device move synchronously, so that the force applied by the loading device just passes through the friction contact position between the friction ring and the friction plate, further improving the accuracy of the test results.

[0063] (5) Since the detection device includes a friction sensor and a positive pressure sensor, the friction sensor is fixedly installed between the sensor support and the rotating frame, and the positive pressure sensor is fixedly installed on the top surface of the loading base plate. Therefore, 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 by the loading device can be detected by the positive pressure sensor.

[0064] (6) In the testing machine of the present invention, since the friction plate is an annular plate provided with a central through hole and is mounted in the lubricating oil groove 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.

[0065] (7) Since a rubber gasket is sandwiched between the motor and the base, the vibration of the motor can be isolated by the rubber gasket, thereby reducing the test error caused by the motor's own vibration when working. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 It is a schematic diagram of the three-dimensional structure of the friction and wear testing machine of the present invention;

[0067] Figure 2 for Figure 1 Schematic diagram of the exploded structure of the friction and wear testing machine.

[0068] Among them, 1-base, 2-main support plate, 3-auxiliary support plate, 4-motor, 5-transmission belt, 6-spindle, 7-rotating 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-guide seat, 16-weight, 17-guide rope, 18-lubricating oil tank, 19-friction ring, 20-sensor support, 21-friction sensor, 2 2-positive pressure sensor, 23-first locking bolt, 24-second locking bolt, 25-friction plate, 26-upper slide rail, 27-loading rope, 28-shaft sleeve, 29-guide groove, 30-fixed pulley, 31-hinged seat, 32-rotating shaft, 33-lifting seat, 34-roller, 35-first laser, 36-second laser, 37-third laser, 38-first vertical rod, 39-second vertical rod, 40-cross rod, 41-light transmission hole DETAILED DESCRIPTION

[0069] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0070] The embodiment of the present invention provides a line contact friction and wear testing machine with a calibration function, such as Figure 1 and Figure 2 As shown in the structure, the test machine includes a base 1, a spindle 6, a driving device, a line contact friction pair, a loading device, a lubricating oil tank 18, a detection device, a control device and a laser calibration device; the base 1 is the basis of the line contact friction and wear tester; for the convenience of description, in the embodiment of the present invention, the 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 direction in which the longitudinal axis extends;

[0071] The main shaft 6 is supported on the top of the base 1 in the horizontal direction. The main shaft 6 has an axis extending in the horizontal direction and is supported on the top of the base 1 so as to be rotatable around the axis.

[0072] The driving device 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 device can control and adjust the rotation speed of the main shaft 6, so as to control the rotation speed of the friction ring 19 rotating with the main shaft 6;

[0073] The line contact friction pair comprises a friction ring 19 concentrically mounted on the end of the main shaft 6 and a friction plate 25 whose surface forms a constant line contact friction with the outer peripheral surface of the friction ring 19; the friction ring 19 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 19 and the surface of the friction plate 25; a threaded hole is arranged on the end surface of the main shaft 6; the friction ring 19 is mounted on the main shaft 6 through a first locking bolt 23; the end surface of the friction ring 19 is arranged parallel to the end surface of the main shaft 6;

[0074] The loading device is installed on the base 1 and the main shaft 6, and is used to push the friction plate 25 toward the friction ring 19 to adjust the positive pressure between the friction plate 25 and the friction ring 19;

[0075] The lubricating oil groove 18 is installed on the loading device, 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 25 and the friction ring 19; 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 25 is detachably installed on the inner bottom surface of the lubricating oil groove 18; the friction plate 25 is an annular plate provided with a central through hole, and the upper surface of the bottom plate of the lubricating oil groove 18 can be provided with a threaded hole (not shown in the figure), and is installed in the lubricating oil groove 18 by threading the second locking bolt 24 penetrated through the central through hole and the threaded hole on the upper surface of the bottom plate; the friction plate 25 can be reused by rotating; when conducting a friction and wear test, the lubricating oil groove 18 can contain lubricating oil;

[0076] The detection device is used to detect the normal pressure and friction between the friction plate 25 and the friction ring 19;

[0077] The control device is signal-connected with the driving device and the detection device to obtain the detection signal of the detection device;

[0078] The laser calibration device has its bottom end mounted on the base 1 and is located outside the loading device, and is used to calibrate the initial position of the loading device by laser.

[0079] The above-mentioned line contact friction and wear testing machine supports a main shaft 6 and a driving device for driving the main shaft 6 to rotate on the base 1. The line contact friction pair includes a friction ring 19 installed at the end of the main shaft 6 and a friction plate 25 installed in the lubricating oil groove 18. The friction ring 19 is driven to rotate by the main shaft 6, so that the friction ring 19 and the friction plate 25 are in line contact friction; the loading device is used to adjust the positive pressure between the friction plate 25 and the friction ring 19, and the friction test of the friction ring 19 and the friction plate 25 under different pressure conditions can be realized through the loading device; the lubricating oil groove 18 can ensure a continuous and stable lubrication environment for the line contact friction pair. The lubricating oil groove 18 can swing around the axis of the main shaft 6 and around the longitudinal axis. The swing of the lubricating oil groove 18 can make the friction plate 25 always maintain a constant line contact friction state with the friction ring 19, and the lubricating oil groove 18 can make the friction ring 19 and the friction plate 25 always have good lubrication conditions; the detection device is used to detect the friction The positive pressure and friction force between the plate 25 and the friction ring 19; the laser calibration device is used to calibrate the initial position of the loading device through a laser, so that the positive pressure applied by the loading device just passes through the geometric center of the friction ring 19, so that the loading is accurate during the friction and wear test; 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, thereby avoiding the defect that when there is an angle between the outer surface of the friction ring 19 and the friction plate 25, the friction ring 19 and the friction plate 25 form a point contact due to the existence of a gap, and the stable line contact condition cannot be achieved; when the loading device has a swinging degree of freedom, the loading force of the friction plate 25 and the reaction force of the friction ring 19 will form a restoring torque, so that the loading device swings in the direction of reducing the angle, and the friction plate 25 will get close to the friction ring 19 until the friction pair reaches a stable line contact, thereby improving the accuracy of the friction and wear test results.

[0080] The friction plate 25 of the above-mentioned testing machine is 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. Therefore, after a single friction and wear test is completed, the friction plate 25 can be rotated around the axis of its central through hole and then fixed, and the surface portion of the friction plate 25 that does not participate in the friction is used as the friction pair contact surface of the next test, so that the friction plate 25 can be repeatedly used by rotation, which can greatly improve the utilization rate of the test material and reduce unnecessary waste.

[0081] In a specific implementation manner, Figure 1 and Figure 2As shown in the structure, the laser calibration device includes three lasers and a laser fixing frame; the laser fixing frame is a door-type bracket, including two vertical rods symmetrically arranged on both sides of the main axis and a cross bar 40 fixedly connected to the top ends of the two vertical rods; the center line of the cross bar 40 is arranged parallel to the longitudinal axis; wherein the three lasers may be a first laser 35, a second laser 36 and a third laser 37, and the two vertical rods may be a first vertical rod 38 and a second vertical rod 39 symmetrically arranged with the axis center line of the main axis 6 as the axis of symmetry, the first vertical rod 38 and the second vertical rod 39 both extend in the vertical direction, and the bottom ends of the two vertical rods can be adjustably mounted on the top surface of the base 1 along the axial position of the main axis 6; a laser is mounted on each of the vertical rod and the cross bar 40. The laser mounted on the crossbar 40 is used to emit a vertical laser beam that is directed toward the geometric center of the friction ring and propagates in the vertical direction; the laser mounted on the vertical bar is used to emit a horizontal laser beam that is directed toward the geometric center of the friction ring 19 and propagates in the horizontal direction; a first laser 35 is mounted in the middle of the first vertical bar 38, a second laser 36 is mounted in the middle of the second vertical bar 38, and a third laser 37 is mounted in the middle of the crossbar 40; the first laser 35 and the second laser 36 are arranged opposite to each other and are used to emit laser beams that propagate oppositely and longitudinally; the third laser 37 is used to emit a laser beam that propagates in the vertical direction downwardly; a light-transmitting hole for passing the vertical laser beam and the horizontal laser beam is provided in the loading device. When the friction ring 19 is not installed on the spindle 6, the three laser beams emitted by the first laser 35, the second laser 36 and the third laser 37 converge at the geometric center of the friction ring. When the friction ring 19 is installed on the spindle 6, the laser beams emitted by the first laser 35, the second laser 36 and the third laser 37 are blocked by the friction ring 19, so that the laser beams emitted by the first laser 35, the second laser 36 and the third laser 37 are irradiated on the outer peripheral surface corresponding to the geometric center of the friction ring 19. The geometric center of the friction ring 19 is the point where the axial center and the radial center of the friction ring 19 intersect.

[0082] The above-mentioned testing machine emits lasers to the geometric center of the friction ring 19 through the three lasers of the laser calibration device, so that the laser beams emitted by the lasers located at the top and both sides of the loading device converge at the geometric center of the friction ring 19. A light-transmitting hole 41 for transmitting the laser beam is provided on the loading device, so that the initial position of the loading device can be calibrated through the light-transmitting hole 41 to avoid the phenomenon of deviation of the installation position of the loading device, so that the loading device is loaded accurately and swings in the direction of reducing the angle between the friction ring 19 and the friction plate 25 under the action of the restoring torque to ensure constant line contact, thereby further improving the accuracy of the friction and wear test.

[0083] In the above test machine, Figure 1 and Figure 2 As shown in the structure, the driving device includes a motor 4, a transmission belt 5, a sleeve 28, a support plate and a rotating frame 7;

[0084] The motor 4 is fixedly mounted on the base 1, and is connected to the main shaft 6 through the transmission belt 5, so as to drive the main shaft 6 to rotate; the 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 motor 4 and the base 1; the base 1 is provided with a notch (not shown in the figure) for the transmission belt 5 to pass through;

[0085] 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 motor 4; the rotating frame 7 can be installed on the end of the sleeve 28 close to the friction ring 19 in a swingable manner around the axis of the main shaft 6, and is used to support the loading device and enable the loading device to have a degree of rotational freedom around the axis of the main shaft 6; the rotating frame 7 is a hollow block structure and has at least four side surfaces evenly distributed along the circumferential direction; the rotating 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 rotation of the rotating frame 7 relative to the sleeve 28 is realized by the bearing; the rotation axis of the rotating frame 7 coincides with the axis of the main shaft 6; the control device is connected to the motor 4 signal for controlling the motor 4 and obtaining the working status information of the motor 4.

[0086] Since the shaft sleeve 28 of the driving device is fixedly mounted on the base 1 through the support plate, and the main shaft 6 is mounted in the shaft sleeve 28 through the bearing, the rotation installation of the main shaft 6 is realized by the shaft sleeve 28 and the support plate; since the rotating frame 7 is a hollow block structure, it can be swingably mounted on one end of the shaft sleeve 28 to support the loading device, and enable the loading device to have the freedom of swinging around the axis of the main shaft 6, so that the loading device can swing with the friction plate 25, thereby avoiding the deformation of the sensitive element of the friction sensor causing the friction plate 25 to swing around the axis of the main shaft 6, resulting in the loading force being 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 accuracy and repeatability of the test results.

[0087] Since a rubber gasket is sandwiched between the motor 4 and the base 1 , the vibration of the motor 4 can be isolated through the rubber gasket, thereby reducing the test error caused by the vibration of the motor 4 itself when it is working.

[0088] Furthermore, if Figure 1 and Figure 2As 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;

[0089] The two adjustable outer rails 8 are symmetrically distributed on both sides of the rotating frame 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 1 and Figure 2 As shown in the structure, a fixed slider is fixedly installed on the surface of one side of the rotating 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 rotating frame 7; the fixed slider and the rotating 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;

[0090] 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 rotating 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 loading device along the longitudinal axis can be released;

[0091] 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;

[0092] 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 27 are symmetrically arranged on both sides of the loading base plate 10;

[0093] 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, so as to measure the positive pressure between the friction plate 25 and the friction ring 19;

[0094] The lubricating oil tank 18 is fixedly mounted on the top of the loading platform 11;

[0095] The loading device drives the friction plate 25 to apply positive pressure to the friction ring 19 through the loading base plate 10;

[0096] The fulcrum frame 13 is fixedly mounted on the top of the rotating frame 7, and the upper slide rail 26 is pressed against the top of the rotating frame 7; the fulcrum frame 13 may be an H-shaped structure;

[0097] The top center of the guide force component frame 12 is fixedly installed on the end of the upper slide rail 26, and is an inverted U-shaped structure. A guide groove 29 and a fixed pulley 30 for guiding the loading rope 27 are provided on both sides.

[0098] 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 is arranged in parallel with the central axis of the lever 14; 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 with 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 arranged in parallel with the main shaft 6, and the axis of the roller 34 is parallel to the axis of the main shaft 6 and located in the same vertical plane;

[0099] The two loading ropes 27 are parallel and both have a closed loop structure. The tops of the two loading ropes 27 are suspended on the rollers 34, and the bottoms are sleeved on the outer peripheral side of the loading base plate 10. The middle part is 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 two loading ropes 27 are in a taut state, and the loading force generated by the lever 14 can be transmitted to the loading base plate 10. By using two loading ropes 27 of the same length, the laser beam emitted by the third laser 37 can pass through the middle of the two loading ropes 27, avoiding the blocking of the laser beam by the loading ropes 27.

[0100] The bottom end of the guide rope 17 passes around the guide seat 15 and is connected to a loading weight 16;

[0101] The guide seat 15 is fixedly installed on the base 1 and is located at the bottom of the other end of the lever 14. Two fixed pulleys are arranged inside the guide seat 15 to rotate around a horizontal axis. The middle part of the guide rope 17 is controlled to extend in the horizontal direction through the two fixed pulleys. The central axes of the two fixed pulleys 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 passes around the part between the two fixed pulleys in the guide seat 15 and is parallel to the axis 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.

[0102] The vertical rod is located outside the adjustable outer rail 8, and the crossbar 40 is located on the top side of the lever 14; Figure 1 As shown in the structure, an adjustable outer rail 8 is provided on both sides of the main shaft 6, and a vertical rod is provided on the outer side of each adjustable outer rail 8, and the vertical rods are respectively a first vertical rod 38 and a second vertical rod 39; a cross rod 40 is provided on the top of the lever 14;

[0103] A light-transmitting hole 41 penetrating in the vertical direction is provided on the hanging seat 33, the rotating shaft 32, the roller 34, the upper slide rail 26, and the guide force component frame 12, for transmitting the vertical laser beam emitted by the third laser 35;

[0104] The adjustable outer rail 8 , the loading outer frame 9 and the rotating shaft for rotatably connecting the adjustable outer rail 8 and the loading outer frame 9 are all provided with light-transmitting holes 41 penetrating along the longitudinal axis for transmitting the horizontal laser beams emitted by the first laser 35 and the second laser 36 .

[0105] The above-mentioned testing machine is provided with light-transmitting holes 41 on the components corresponding to the optical path of the laser. The rotating shaft and roller used in the loading device can adopt cylindrical pin shafts with through holes in the middle to form the light-transmitting holes 41. When calibrating, the laser is started, and the position of the loading device is adjusted so that the lasers generated by the first laser 35 and the second laser 36 pass through the light-transmitting holes 41 of the adjustable slide rail 8, the loading outer frame 9, and the rotating shaft installed between the adjustable slide rail 8 and the loading outer frame 9, so that the lasers are irradiated on the circumferential surface of the friction ring 19 to form light spots, and it is ensured that the light spots are in the middle position of the circumferential surface, so that the rotating shaft of the loading device passes through the axial center and radial center of the friction ring 19; the position of the lever 14 is adjusted so that the lasers generated by the third laser 37 pass through the light-transmitting holes 41 of the lifting seat 33, the rotating shaft 32, the roller 34, the upper slide rail 26, and the guide force component rod 12, so that the lasers form light spots on the circumferential surface of the friction ring, and it is ensured that the light spots are in the middle position of the circumferential surface of the friction ring, so that the loading force can be accurately loaded. The above structure ensures that the loading device can swing synchronously with the rotating frame 7 around the axis of the main shaft 6, and the position of the loading device is calibrated by the laser beam emitted by the laser before the test. It 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 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.

[0106] Specifically, the detection device also includes a sensor support 20 and a friction sensor 21; the sensor support 20 is fixedly mounted on the base 1; the sensor support 20 can be an L-shaped structure, with a small hole for mounting the friction sensor 21 on the top, the friction sensor 21 is fixedly mounted on the top of the sensor support 20, and is connected to the rotating frame 7, and is used to detect the friction transmitted by the rotating frame 7; the friction sensor 21 can be connected to the rotating frame 7 through a T-shaped plate, and when the rotating frame 7 is subjected to the friction transmitted by the friction plate 25, the friction sensor 21 Due to the tensile force, a corresponding deformation signal will be generated; 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 force sensor 21 and the positive pressure sensor 22 signal.

[0107] Since the detection device includes a friction sensor 21 and a positive pressure sensor 22, the friction sensor 21 is fixedly installed between the sensor support 20 and the rotating frame 7, and the positive pressure sensor 22 is fixedly installed on the top surface of the loading base plate 10. Therefore, the friction force between the friction ring 19 and the friction plate 25 can be detected by the friction sensor 21, and at the same time, the positive pressure applied by the loading device can be detected by the positive pressure sensor 22.

[0108] On the basis of the above various embodiments, the above test machine further includes a display device connected to the control device signal and a speed sensor installed on the motor 4; the display device and the control device can be an integral structure; according to the signal obtained by the control device, the display device is used to display the working state information of the motor 4, the values ​​collected by the friction 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.

[0109] The display device can be used to conveniently display various operating parameters and collected parameters of the test machine; the speed sensor can be used to conveniently detect the speed of the motor 4, and the speed sensor and the control device can monitor and adjust the relative speed between the friction plate 25 and the friction ring 19.

[0110] During the test using the above-mentioned testing machine, 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 restriction 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 located at the inner bottom of the lubricating oil groove 18, the friction plate 25 moves upward with the lubricating oil groove 18. After the end face of the friction plate 25 is tangent to the outer peripheral surface of the friction ring 19 and is completely fitted, 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 and the end surface of the friction plate 25 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 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 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 and the end surface of the friction plate 25 are tangent 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.

[0111] The above-mentioned testing machine can realize the constant line contact friction between the friction ring 19 and the friction plate 25. On this basis, the rotation speed of the friction ring 19 is controlled by adjusting the rotation speed of the motor 4, and the magnitude of the positive pressure is controlled by controlling the mass of the weight 16 of the loading device, 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.

[0112] 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 linear contact friction and wear testing machine with calibration function, characterized in that: include: Pedestal; A main shaft is supported on the top of the base in a horizontal direction; A driving device, 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; a loading device, mounted on the base and the main shaft, for pushing the friction plate toward the friction ring to adjust the normal pressure between the friction plate and the friction ring; A lubricating oil tank is installed on the loading device, 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; 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 loading device 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 loading device 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, thereby improving the accuracy of the friction and wear test results; A detection device, used for detecting the normal pressure and friction force between the friction plate and the friction ring; A control device, connected to the driving device and the detection device by signals, and used to obtain a detection signal from the detection device; A laser calibration device, the bottom end of which is mounted on the base and located outside the loading device, is used to calibrate the initial position of the loading device by laser.

2. The testing machine according to claim 1, characterized in that: The laser calibration device includes three lasers and a laser fixing frame; The laser fixture is a door-shaped bracket, comprising two vertical rods symmetrically arranged on both sides of the main axis and a cross rod fixedly connected to the top ends of the two vertical rods; the center line of the cross rod is arranged parallel to the longitudinal axis; The bottom ends of the two vertical rods can be adjustably mounted on the top surface of the base along the axial position of the main shaft; A laser is installed on each of the vertical rod and the horizontal rod; The laser installed on the horizontal rod is used to emit a vertical laser beam toward the geometric center of the friction ring and propagating in the vertical direction; the laser installed on the vertical rod is used to emit a horizontal laser beam toward the geometric center of the friction ring and propagating in the horizontal direction; The loading device is provided with light-transmitting holes for passing the vertical laser beam and the horizontal laser beam.

3. The testing machine according to claim 2, characterized in that: The driving device includes a motor, a transmission belt, a shaft sleeve, a support plate and a rotating frame; The motor is fixedly mounted on the base and 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 rotating frame is mounted on one end of the sleeve close to the friction ring so as to be able to swing around the axis of the main shaft, and is used to support the loading device; the rotating frame 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 status information of the motor.

4. The testing machine according to claim 3, 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 rotating 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; A shaft that can rotate around the longitudinal axis and the axis of the main shaft is installed between the two adjustable outer rails. The loading outer frame is oscillating; 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 installed on the top of the rotating frame, and the upper slide rail is pressed onto the top of the rotating frame; The top center of the guide force component frame is fixedly installed 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 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 two loading ropes are parallel and both have a closed loop structure, with the tops suspended on the rollers and the bottoms sleeved on the outer peripheral side of the loading base plate, and the middle parts are guided by the guide grooves and fixed pulleys 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 provided with two fixed pulleys rotating around a horizontal axis, and is used to control the middle part of the guide rope to extend in the horizontal direction through the two fixed pulleys; The vertical rod is located on the outer side of the adjustable outer rail, and the horizontal rod is located on the top side of the lever; The hanging seat, the rotating shaft, the roller, the upper slide rail, and the guide force component frame are all provided with light-transmitting holes penetrating in the vertical direction for transmitting the vertical laser beam; The adjustable outer rail and the loading outer frame are both provided with light-transmitting holes penetrating along the longitudinal axis for transmitting the horizontal laser beam.

5. The testing machine according to claim 4, 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 rotating frame, and is used to detect the friction force transmitted by the rotating frame.

6. The testing machine according to claim 5, characterized in that: It also includes a display device connected to the control device 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 rotation speed sensor is signal-connected to the control device and is used to detect the rotation speed of the motor.

7. The testing machine according to any one of claims 1 to 6, 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 by a first locking bolt; 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 penetrating the central through hole; The friction plate can be reused by rotating.

8. The testing machine according to any one of claims 3 to 6, characterized in that: 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.

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