CN115078069A

CN115078069A - Line contact friction wear testing machine with calibration function

Info

Publication number: CN115078069A
Application number: CN202210682305.XA
Authority: CN
Inventors: 付洪宇; 斯杰里马赫·亚历山大; 张昊; 牛鹏豪; 胡晨星; 孙柏刚; 王字满; 郭意桥
Original assignee: Beijing Institute of Technology BIT
Current assignee: Beijing Institute of Technology BIT
Priority date: 2022-06-15
Filing date: 2022-06-15
Publication date: 2022-09-20

Abstract

The invention discloses a linear contact friction wear testing machine with a calibration function, which comprises: a base; a main shaft supported on the top of the base along the horizontal direction; the driving device is fixedly arranged on the base; the linear contact friction pair comprises a friction ring concentrically arranged at the end part of the main shaft and a friction plate the surface of which forms constant linear contact friction with the friction ring; the loading device is arranged on the base and the main shaft; the lubricating oil groove can swing around the axial lead and the longitudinal axis of the main shaft; the detection device is used for detecting the contact pressure and the friction force of the line contact friction pair; and the bottom end of the laser calibration device is installed on the base and used for calibrating the initial position of the loading device through laser. The testing machine can ensure the steady line contact friction of the friction pair, can ensure continuous and stable lubrication, and can calibrate the loading device before the test starts, thereby improving the accuracy of the test result.

Description

Line contact friction wear testing machine with calibration function

Technical Field

The invention relates to the technical field of friction tests, in particular to a linear contact friction wear testing machine with a calibration function.

Background

It is known that when two objects contact each other and there is relative motion between the contact surfaces, friction occurs between the two objects, which in turn causes different degrees of frictional wear. This phenomenon of frictional wear is both beneficial and detrimental and can be used in industrial processes to improve the surface roughness of objects, but can also substantially impair the performance and service life of the production machines. Therefore, if the friction and wear mechanism between the objects in mutual contact can be correctly mastered, social production practice can be guided on the basis of the mechanism, the problem of unnecessary resource loss is reduced, and the working efficiency of equipment is improved. Meanwhile, the method can also provide important reference basis for the research of tribology and related fields.

At present, the scientific community has not formed a complete theoretical system for the friction and wear phenomena between solids, and the research on the deep mechanism of the system is not mature, so that the theoretical analysis is difficult to determine each performance of the friction pair. However, in an industrial process, in order to correctly design the matching relationship between the friction members, it is necessary to correctly and effectively evaluate the friction characteristics of the friction pair. Therefore, it is necessary to design a proper friction and wear machine to obtain the friction coefficient, wear characteristics, etc. between the respective materials.

In the prior art, a friction and wear testing machine for a linear contact friction and wear test has the problems that the balance cannot be accurately kept and the linear contact cannot be stabilized between linear contact friction pairs because vibration is inevitably generated in the rotation process of a main shaft and the contact state between the friction pairs is damaged in the measurement process of a friction force sensor, and the problems can cause uneven load loading and inaccurate results. In addition, some studies need to consider the friction characteristics of the friction pair under stable lubrication conditions, but most friction and wear machines often cannot provide a continuous and stable lubrication environment.

Disclosure of Invention

In view of this, the present invention provides a linear contact friction wear testing machine with a calibration function, which can ensure constant linear contact friction of a friction pair by a release degree of freedom, can ensure a continuous and stable lubrication environment, and can calibrate a loading device before a test is started, thereby improving the accuracy of a test result.

The invention adopts the following specific technical scheme:

a line contact friction wear tester with a calibration function, the tester comprising:

a base;

a main shaft supported on the top of the base along the horizontal direction;

the driving device is fixedly arranged on the base and used for driving the main shaft to rotate;

the linear contact friction pair comprises a friction ring concentrically arranged at the end part of the main shaft and a friction plate of which the surface forms constant linear contact friction with the outer peripheral surface of the friction ring;

the loading device is arranged on the base and the main shaft and used for pushing the friction plate towards the direction of the friction ring so as to adjust the positive pressure between the friction plate and the friction ring;

the lubricating oil groove is arranged on the loading device, the top of the lubricating oil groove is provided with an opening, and the lubricating oil groove can swing around the axis line and the longitudinal axis of the main shaft and is used for containing lubricating oil; the axis line of the main shaft is vertically intersected with the longitudinal axis in a horizontal plane; the friction plate is detachably arranged on the inner bottom surface of the lubricating oil groove;

the detection device is used for detecting positive pressure and friction force between the friction plate and the friction ring;

the control device is in signal connection with the driving device and the detection device and is used for acquiring a detection signal of the detection device;

and the bottom end of the laser calibration device is installed on the base and positioned outside the loading device, and is used for calibrating the initial position of the loading device through laser.

Furthermore, the laser calibration device comprises three lasers and a laser fixing frame;

the laser fixing frame is a door-shaped support and comprises two vertical rods symmetrically arranged on two sides of the main shaft and a cross rod fixedly connected to the top ends of the two vertical rods; the center line of the cross rod is arranged in parallel with 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;

the vertical rods and the cross rods are respectively provided with the laser;

the laser mounted on the cross bar is used for emitting a vertical laser beam which faces the geometric center of the friction ring and propagates along the vertical direction; the laser mounted on the vertical rod is used for emitting a horizontal laser beam which faces the geometric center of the friction ring and propagates along the horizontal direction;

and the loading device is provided with light holes for passing through the vertical laser beams and the horizontal laser beams.

Furthermore, the driving device comprises a motor, a transmission belt, a shaft sleeve, a supporting plate and a rotating frame;

the motor is fixedly arranged on the base and is in transmission connection with the main shaft through the transmission belt;

the shaft sleeve is fixedly arranged on the base through the supporting plate;

the main shaft is arranged in the shaft sleeve through a bearing, and the shaft axis of the main shaft is parallel to the shaft axis of the motor;

the rotating frame can be arranged at one end, close to the friction ring, of the shaft sleeve in a swinging mode around the axis line of the main shaft and is used for supporting the loading device; the rotating frame is of a hollow block structure and is provided with at least four side surfaces which are uniformly distributed along the circumferential direction;

the control device is in signal connection with the motor and is used for controlling the motor and acquiring the working state information of the motor.

Furthermore, the loading device comprises two adjustable outer rails, a loading outer frame, a loading bottom plate, a loading platform, a guiding force-dividing frame, an upper sliding rail, a fulcrum frame, a lever, a guiding seat, weights, a guiding rope and a loading rope;

the two adjustable outer rails are symmetrically distributed on two sides of the rotating frame and can slide along the axial direction of the main shaft, and the central axis of each adjustable outer rail is parallel to the axial lead 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 arranged between the two adjustable outer rails;

four corners inside the loading outer frame are provided with sliding guide rails extending along the vertical direction;

along the vertical direction, the loading platforms are arranged at the top of the loading bottom plate at intervals; the outer peripheral surfaces of the loading platform and the loading bottom plate are in sliding fit with the inner side surfaces of the sliding guide rails;

the detection device comprises a positive pressure sensor fixedly arranged on the top surface of the loading bottom plate, and the positive pressure sensor is used for detecting the positive pressure applied to the loading platform by the loading bottom plate;

the lubricating oil groove is fixedly arranged at 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 arranged at the top of the rotating frame, and the upper sliding rail is connected to the top of the rotating frame in a pressing mode;

the center of the top end of the guide force-dividing frame is fixedly arranged at the end part of the upper sliding rail and is of an inverted U-shaped structure, and a guide groove and a fixed pulley for guiding the loading rope are arranged on two sides of the guide force-dividing frame;

the central axis of the lever and the axis of the main shaft are positioned 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, the middle part of the lever is arranged at the top of the fulcrum frame through a hinge seat in a swinging manner, one end of the lever is hinged with a hoisting seat through a rotating shaft, and the other end of the lever is connected with the guide rope; the swing axis of the lever is parallel to the longitudinal axis; the top end of the hoisting seat can swing around the axis of the rotating shaft, and the axis of the rotating shaft is parallel to the longitudinal axis and is positioned in the same vertical plane; a rolling shaft is arranged at the bottom end of the hoisting seat, and the axis of the rolling shaft is parallel to the axis of the main shaft and is positioned in the same vertical plane;

the two loading ropes are parallel and are of closed loop structures, the tops of the two loading ropes are suspended on the rolling shafts, the bottoms of the two loading ropes are sleeved on the outer peripheral sides of the loading bottom plates, and the middle parts of the two loading ropes are guided through the guide grooves and the fixed pulleys of the guide force-dividing frame and the fixed pulleys on the two sides of the loading bottom plates;

the bottom end of the guide rope bypasses the guide seat and is connected with the weight;

the guide seat is fixedly arranged on the base and positioned at the bottom of the lever, and two fixed pulleys rotating around a horizontal axis are arranged inside the guide seat and used for controlling the middle part of the guide rope to extend along the horizontal direction through the two fixed pulleys;

the vertical rods are positioned on the outer side of the adjustable outer rail, and the transverse rods are positioned on the top side of the lever;

light holes which are penetrated through along the vertical direction are formed in the hoisting seat, the rotating shaft, the rolling shaft, the upper sliding rail and the guiding force-dividing frame and are used for transmitting the vertical laser beam;

and light holes which are communicated along the longitudinal axis are formed in the adjustable outer rail and the loading outer frame and are used for transmitting the horizontal laser beams.

Still further, the detection device further comprises a sensor support and a friction force sensor;

the sensor support is fixedly arranged on the base;

the friction force sensor is fixedly arranged at the top of the sensor support, is connected with the rotating frame and is used for detecting the friction force transmitted by the rotating frame.

Furthermore, the device also comprises a display device in signal connection with the control device and a rotating speed sensor arranged on the motor;

according to the signals acquired by the control device, the display device is used for displaying the working state information of the motor, and numerical values acquired by the friction force sensor and the positive pressure sensor;

the rotating speed sensor is in signal connection with the control device and is used for detecting the rotating speed of the motor.

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

the friction ring is mounted on the main shaft through a first locking bolt;

the friction plate is an annular plate provided with a central through hole and is arranged in the lubricating oil groove through a second locking bolt penetrating through the central through hole;

the friction plate can be reused by rotating.

Furthermore, the motor is fixedly arranged at the bottom of the base, and a rubber gasket is clamped between the motor and the base;

the base is provided with a gap for the transmission belt to pass through.

Has the advantages that:

(1) the testing machine provided by the invention is characterized in that a main shaft and a driving device for driving the main shaft to rotate are supported on a base, a linear contact friction pair comprises a friction ring arranged at the end part of the main shaft and a friction plate arranged in a lubricating oil groove, and the friction ring is driven to rotate by the main shaft so as to perform linear contact friction on the friction ring and the friction plate; the loading device is used for adjusting positive pressure between the friction plate and the friction ring, and friction tests under different pressure conditions are realized through the loading device; the lubricating oil groove can ensure the continuous and stable lubricating environment of the linear contact friction pair, and the friction plate can always keep a constant linear contact friction state with the friction ring through the swinging of the lubricating oil groove around the shaft axis and the longitudinal axis of the main shaft which are vertically crossed in the horizontal plane, and the friction ring and the friction plate can always have a better lubricating condition through the lubricating oil groove; the detection device is used for detecting positive pressure and friction force between the friction plate and the friction ring; the laser calibration device is used for calibrating the initial position of the loading device through laser, so that the positive pressure applied by the loading device just passes through the geometric center of the friction ring, and the loading is accurate in the friction and wear test process; therefore, when the linear contact friction and wear testing machine is used for a friction and wear test, the steady linear contact condition of the linear contact friction pair can be ensured by releasing the freedom degree, and the defect that the stable linear contact condition cannot be achieved due to point contact formed when the angle exists between the outer surface of the conventional friction ring and the friction plate is avoided; when the loading device has the swinging freedom degree, the loading force of the friction plate and the reaction force of the friction ring can form a restoring moment, so that the loading device swings towards the direction of reducing the angle, the friction plate can be close to the friction ring until the friction pair reaches stable line contact, and the accuracy of the friction and wear test result is improved.

(2) The testing machine provided by the invention emits laser to the geometric center of the friction ring through the three lasers of the laser calibration device, so that laser beams emitted by the lasers positioned at the top and at the two sides of the loading device are intersected at the geometric center of the friction ring, and the loading device is provided with the light transmitting holes for transmitting the laser beams, so that the initial position of the loading device can be calibrated through the light transmitting holes, the phenomenon that the mounting position of the loading device deviates is avoided, the loading device is accurately loaded, and the accuracy of a friction wear test is further improved.

(3) According to the testing machine, a shaft sleeve of the driving device is fixedly arranged on the base through the supporting plate, the main shaft is arranged in the shaft sleeve through the bearing, and the rotating installation of the main shaft is realized through the shaft sleeve and the supporting plate; the rotating frame is of a hollow block structure and can be arranged at one end, close to the friction ring, of the shaft sleeve in a swinging mode to support the loading device, the loading device can have swinging freedom degree around the axis of the main shaft through the rotating frame arranged on the shaft sleeve in a swinging mode, the loading device can swing along with the friction plate, and therefore the situation that the loading force is not perpendicular to the contact surface due to the fact that the friction plate swings around the axis of the main shaft due to the fact that the sensitive element of the friction force sensor deforms is avoided, the principle defect that the friction force measuring process of the friction force sensor can affect the contact state of the friction pair is overcome, the fact that positive pressure is perpendicular to the contact surface all the time in the friction force measuring process is guaranteed, and accuracy and repeatability of test results are improved.

(4) The loading device of the testing machine comprises two adjustable outer rails, a loading outer frame, a loading bottom plate, a loading platform, a guiding force-dividing frame, an upper sliding rail, a fulcrum frame, a lever, a guide seat, a weight, a guiding rope and a loading rope, wherein a light hole is formed in a part corresponding to a light path of a laser, so that the loading device can synchronously swing around the axis of a main shaft along with a rotating frame, the position of the loading device is calibrated through a laser beam emitted by the laser before a test, and the loading device can synchronously swing around a longitudinal axis along with the loading outer frame in the loading process, a linear contact friction pair and the loading device synchronously move, the acting force applied by the loading device just passes through the friction contact position of a friction ring and a friction plate, and the accuracy of a test result is further improved.

(5) Because the detection device comprises the friction force sensor and the positive pressure sensor, the friction force sensor is fixedly arranged between the sensor support and the rotating frame, and the positive pressure sensor is fixedly arranged on the top surface of the loading bottom plate, the friction force between the friction ring and the friction plate can be detected through the friction force sensor, and meanwhile, the positive pressure applied by the loading device can be detected through the positive pressure sensor.

(6) According to the testing machine, the friction plate is the annular plate provided with the central through hole and is arranged in the lubricating oil groove through the second locking bolt penetrating through the central through hole, so that after a single friction and abrasion test is completed, the friction plate can rotate around the axis of the central through hole and then is fixed, and the surface part of the friction plate not participating in friction is used as a friction pair contact surface of the next test, so that the friction plate can be repeatedly utilized for many times through rotation, the utilization rate of test materials can be greatly improved, and unnecessary waste is reduced.

(7) Because press from both sides between motor and base and be equipped with the rubber gasket, can keep apart the vibration of motor through the rubber gasket to weaken the motor during operation self vibration and the experimental error that causes.

Drawings

FIG. 1 is a schematic perspective view of a frictional wear testing machine according to the present invention;

fig. 2 is a schematic diagram of an explosive structure of the friction wear tester in fig. 1.

Wherein, 1-a base, 2-a main support plate, 3-a secondary support plate, 4-a motor, 5-a transmission belt, 6-a main shaft, 7-a rotating frame, 8-an adjustable outer rail, 9-a loading outer frame, 10-a loading bottom plate, 11-a loading platform, 12-a guiding force-dividing frame, 13-a fulcrum frame, 14-a lever, 15-a guiding seat, 16-a weight, 17-a guiding rope, 18-a lubricating oil groove, 19-a friction ring, 20-a sensor support, 21-a friction force sensor, 22-a positive pressure sensor, 23-a first locking bolt, 24-a second locking bolt, 25-a friction plate, 26-an upper sliding rail, 27-a loading rope, 28-a shaft sleeve, 29-a guiding groove and 30-a fixed pulley, 31-hinged seat, 32-rotating shaft, 33-hoisting seat, 34-rolling shaft, 35-first laser, 36-second laser, 37-third laser, 38-first vertical rod, 39-second vertical rod, 40-cross rod and 41-light hole

Detailed Description

The invention is described in detail below by way of example with reference to the accompanying drawings.

The embodiment of the invention provides a linear contact friction wear testing machine with a calibration function, which comprises a base 1, a main shaft 6, a driving device, a linear contact friction pair, a loading device, a lubricating oil groove 18, a detection device, a control device and a laser calibration device, wherein the main shaft 6, the driving device, the linear contact friction pair, the loading device, the lubricating oil groove 18, the detection device and the control device are sequentially arranged in the base; the base 1 is the basis of a linear contact friction wear testing machine; for convenience of description, in the embodiment of the present invention, a direction from left to right of a page in fig. 1 of the specification is defined as a transverse direction, i.e., an axial direction of a principal axis, a direction from top to bottom of the page in fig. 1 of the specification is defined as a vertical direction, and a direction perpendicular to the page in fig. 1 of the specification is defined as a longitudinal direction, i.e., an extending direction of a longitudinal axis;

the main shaft 6 is supported on the top of the base 1 along the horizontal direction, the main shaft 6 has a shaft axis extending along the horizontal direction along the transverse direction, and is supported on the top of the base 1 in a manner of rotating around the shaft axis;

the driving device is fixedly arranged on the base 1 and used for driving the main shaft 6 to rotate and providing 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;

the line contact friction pair comprises a friction ring 19 concentrically arranged at the end part of the main shaft 6 and a friction plate 25 the surface of which forms a constant line contact friction with the outer peripheral surface of the friction ring 19; the friction ring 19 is arranged concentrically with the main shaft 6 and is detachably mounted at the end part of the main shaft 6; the outer peripheral surface of the friction ring 19 and the surface of the friction plate 25 form a constant line contact friction; the end face of the main shaft 6 is provided with a threaded hole; the friction ring 19 is mounted to the main shaft 6 by a first locking bolt 23; the end surface of the friction ring 19 is arranged in parallel with the end surface of the main shaft 6;

the loading device is arranged on the base 1 and the main shaft 6 and is used for pushing the friction plate 25 towards the friction ring 19 so as to adjust the positive pressure between the friction plate 25 and the friction ring 19;

the lubricating oil groove 18 is arranged on the loading device, the top of the lubricating oil groove is provided with an opening, the lubricating oil groove can swing around the axial lead and the longitudinal axis of the main shaft 6 and is used for containing lubricating oil to lubricate the friction part of the friction plate 25 and the friction ring 19; the axis of the main shaft 6 is vertically intersected with the longitudinal axis in a horizontal plane, namely, the axis of the main shaft 6 and the longitudinal axis are both in the same horizontal plane, and the axis of the main shaft 6 is vertically intersected with the longitudinal axis; the friction plate 25 is detachably mounted 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, 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 the lubricating oil groove 18 is in threaded connection with the threaded hole on the upper surface of the bottom plate through a second locking bolt 24 penetrating through the central through hole; the friction plate 25 can be reused by rotating; when the friction and wear test is carried out, lubricating oil can be contained in the lubricating oil groove 18;

the detection device is used for detecting the positive pressure and the friction force between the friction plate 25 and the friction ring 19;

and the bottom end of the laser calibration device is installed on the base 1 and is positioned on the outer side of the loading device, and the laser calibration device is used for calibrating the initial position of the loading device through laser.

The linear contact friction wear testing machine is characterized in that a main shaft 6 and a driving device for driving the main shaft 6 to rotate are supported on a base 1, a linear contact friction pair comprises a friction ring 19 arranged at the end part of the main shaft 6 and a friction plate 25 arranged in a lubricating oil groove 18, and the main shaft 6 drives the friction ring 19 to rotate so as to enable the friction ring 19 and the friction plate 25 to carry out linear contact friction; the loading device is used for adjusting positive pressure between the friction plate 25 and the friction ring 19, and friction tests 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 guarantee the continuous and stable lubricating environment of the line contact friction pair, the lubricating oil groove 18 can swing around the axis line of the main shaft 6 and can also swing around the longitudinal axis, the friction plate 25 and the friction ring 19 can always keep a constant line contact friction state through the swinging of the lubricating oil groove 18, and the friction ring 19 and the friction plate 25 can always have a better lubricating condition through the lubricating oil groove 18; the detection device is used for detecting the positive pressure and the friction force between the friction plate 25 and the friction ring 19; the laser calibration device is used for calibrating the initial position of the loading device through laser, so that the positive pressure applied by the loading device just passes through the geometric center of the friction ring 19, and the loading is accurate in the friction and wear test process; therefore, when the linear contact friction and wear testing machine is used for a friction and wear test, the steady linear contact condition of the linear contact friction pair can be ensured by releasing the degree of freedom, and the defects that when the outer surface of the conventional friction ring 19 and the friction plate 25 have an angle, the friction ring 19 and the friction plate 25 form point contact due to the existence of a gap and cannot achieve a stable linear contact condition are avoided; when the loading device has a swinging freedom degree, the loading force of the friction plate 25 and the reaction force of the friction ring 19 form a restoring moment, so that the loading device swings towards the direction of reducing the angle, the friction plate 25 is close to the friction ring 19 until the friction pair reaches stable line contact, and the accuracy of the friction and wear test result is improved.

The friction plate 25 of the testing machine is an annular plate provided with a central through hole, and is arranged in the lubricating oil groove 18 through the second locking bolt 24 penetrating through the central through hole, so that after a single friction and abrasion test is completed, the friction plate 25 can be fixed after rotating around the axis of the central through hole, the surface part of the friction plate 25 not participating in friction is used as a friction pair contact surface of the next test, the friction plate 25 can be reused for many times through rotation, the utilization rate of test materials can be greatly improved, and unnecessary waste is reduced.

In one specific embodiment, as shown in the structure of fig. 1 and 2, the laser alignment device comprises three lasers and a laser holder; the laser fixing frame is a door-shaped support and comprises two vertical rods symmetrically arranged on two sides of the main shaft and a cross rod 40 fixedly connected to the top ends of the two vertical rods; the center line of the crossbar 40 is disposed parallel to the longitudinal axis; the three lasers can be a first laser 35, a second laser 36 and a third laser 37, the two vertical rods can be a first vertical rod 38 and a second vertical rod 39 which are symmetrically arranged by taking the axial lead of the main shaft 6 as a symmetry axis, 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 shaft 6; a laser is arranged on each vertical rod and each cross rod 40; a laser mounted to the crossbar 40 for emitting a vertical laser beam directed towards the geometric center of the friction ring and propagating in the vertical direction; the laser mounted on the vertical rod is used for emitting a horizontal laser beam which faces the geometric center of the friction ring 19 and propagates along the horizontal direction; a first laser 35 is arranged in the middle of the first vertical rod 38, a second laser 36 is arranged in the middle of the second vertical rod 38, and a third laser 37 is arranged in the middle of the cross rod 40; the first laser 35 and the second laser 36 are disposed oppositely and are used for emitting laser beams which are oppositely and longitudinally propagated; the third laser 37 is used to emit a laser beam propagating in the vertical direction downward; the loading device is provided with light holes for passing through the vertical laser beam and the horizontal laser beam. When the friction ring 19 is not mounted 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, and when the friction ring 19 is mounted 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 a point where the axial center and the radial center of the friction ring 19 intersect.

Above-mentioned testing machine passes through the three laser instrument of laser calibrating device and launches laser to the geometric centre of friction ring 19, the laser beam that makes the laser instrument transmission that is located loading device top and both sides intersect in the geometric centre of friction ring 19, be provided with the light trap 41 of transmission laser beam on loading device, thereby can calibrate loading device's initial position through light trap 41, the phenomenon that the mounted position is skew appears in the avoidance of loading device, make loading device loading accurate and to reducing under the effect of restoring moment contained angle direction swing between friction ring 19 and the friction plate 25 in order to guarantee the constant line contact, further improve the experimental accuracy of frictional wear.

In the testing machine, as shown in the structures of fig. 1 and 2, the driving device comprises a motor 4, a transmission belt 5, a shaft sleeve 28, a supporting plate and a rotating frame 7;

the motor 4 is fixedly arranged on the base 1, is in transmission connection with the main shaft 6 through a transmission belt 5 and is used for driving the main shaft 6 to rotate; the motor 4 can be fixedly arranged at the bottom of the base 1 through bolts, and a rubber gasket (not shown in the figure) is clamped between the motor 4 and the base 1; the base 1 is provided with a gap (not shown in the figure) for the transmission belt 5 to pass through;

the shaft sleeve 28 is fixedly arranged on the base 1 through a supporting plate; as shown in fig. 1 and 2, the support plate may include a main support plate 2 and a sub-support plate 3 disposed in a vertical direction; the main supporting plate 2 and the auxiliary supporting plate 3 form a frame structure with higher rigidity, and provide effective support for the main shaft 6; the main shaft 6 is arranged in the shaft sleeve 28 through a bearing, and the axial lead of the main shaft 6 is parallel to the axial lead of the motor 4; the rotating frame 7 is arranged at one end of the shaft sleeve 28 close to the friction ring 19 in a manner of swinging around the axial lead of the main shaft 6, is used for supporting the loading device and enables the loading device to have the freedom degree of rotation around the axial lead of the main shaft 6; the rotating frame 7 is of a hollow block structure and is provided with at least four side surfaces which are uniformly distributed along the circumferential direction; the rotating frame 7 is provided with a bearing through hole, a bearing is arranged in the bearing through hole, the bearing is sleeved on the outer peripheral side of the shaft sleeve 28, and the rotating frame 7 rotates relative to the shaft sleeve 28 through the bearing; the rotating axis of the rotating frame 7 is superposed with the axis of the main shaft 6; the control device is in signal connection with the motor 4 and is used for controlling the motor 4 and obtaining the working state information of the motor 4.

Because the shaft sleeve 28 of the driving device is fixedly arranged on the base 1 through the supporting plate, the main shaft 6 is arranged in the shaft sleeve 28 through a bearing, and the rotating installation of the main shaft 6 is realized through the shaft sleeve 28 and the supporting plate; the rotating frame 7 is of a hollow block structure and can be arranged at one end of the shaft sleeve 28 in a swinging mode to support the loading device, the loading device is enabled to have a swinging freedom degree around the axis of the main shaft 6, the loading device can swing along with the friction plate 25, and therefore the situation that the loading force is not vertical to the contact surface due to the fact that the friction plate 25 swings around the axis of the main shaft 6 due to deformation of the sensitive element of the friction force sensor is avoided, the principle defect that the friction force measuring process of the friction force sensor 21 can affect the contact state of the friction pair is overcome, the fact that the positive pressure is always vertical to the contact surface in the friction force measuring process is guaranteed, and accuracy and repeatability of a test result are improved.

Because press from both sides between motor 4 and base 1 and be equipped with through the rubber gasket, can keep apart the vibration of motor 4 through the rubber gasket to weaken the test error that motor 4 during operation self vibration and cause.

Further, as shown in the structure of fig. 1 and 2, the loading device comprises two adjustable outer rails 8, a loading outer frame 9, a loading bottom plate 10, a loading platform 11, a guide force-dividing frame 12, an upper sliding 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;

the two adjustable outer rails 8 are symmetrically distributed on two sides of the rotating frame 7 and can slide along the axial direction of the main shaft 6, and the central axis of each adjustable outer rail 8 is parallel to the axial lead of the main shaft 6 and has the same height; as shown in the structure of fig. 1 and 2, a fixed sliding block 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 is in sliding fit with the fixed sliding block to realize sliding adjustment of the adjustable outer rail 8 relative to the rotating frame 7; the fixed slide block and the rotating frame 7 can be in a split structure or an integral structure; the axial position of the loading outer frame 9 along the main shaft 6 can be adjusted through the adjustable outer rail 8;

a loading outer frame 9 which can swing around the longitudinal axis and the axis of the main shaft 6 is arranged between the two adjustable outer rails 8; a mounting hole is formed in one end, facing the lubricating oil groove 18, of the adjustable outer rail 8, namely one end, far away from the rotating frame 7, of the adjustable outer rail 8, and the axis line of the mounting hole is overlapped with the longitudinal axis; the loading outer frame 9 is provided with a rotating shaft corresponding to the mounting hole, and the loading outer frame 9 is arranged between the two symmetrically arranged adjustable outer rails 8 through the rotating fit of the rotating shaft and the mounting hole; a bearing can be arranged between the rotating shaft and the mounting hole; through the rotational fit 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;

four corners inside the loading outer frame 9 are provided with sliding guide rails which extend along the vertical direction and are parallel to each other; the loading outer frame 9 is of a frame structure, and four vertical sliding guide rails are arranged on the inner side of the frame structure and used for guiding the movement directions of the loading bottom plate 10 and the loading platform 11;

in the vertical direction, the loading platforms 11 are arranged at intervals on the top of the loading base plate 10; the outer peripheral surfaces of the loading platform 11 and the loading bottom plate 10 are in sliding fit with the inner side surfaces of the sliding guide rails; fixed pulleys in rolling fit with the loading ropes 27 are symmetrically arranged on two sides of the loading bottom plate 10;

the detection device comprises a positive pressure sensor 22 fixedly arranged on the top surface of the loading baseplate 10; a positive pressure sensor 22 is installed between the loading baseplate 10 and the loading platform 11, and is used for detecting the positive pressure applied to the loading platform 11 by the loading baseplate 10 so as to measure the positive pressure between the friction plate 25 and the friction ring 19;

the lubricating oil groove 18 is fixedly arranged at the top of the object platform 11;

the loading device drives the friction plate 25 to apply positive pressure to the friction ring 19 through the loading bottom plate 10;

the fulcrum frame 13 is fixedly arranged at the top of the rotating frame 7, and the upper slide rail 26 is pressed on the top of the rotating frame 7; the fulcrum frame 13 may be an H-shaped structure;

the top center of the guiding force-dividing frame 12 is fixedly arranged at the end part of the upper slide rail 26, and is of an inverted U-shaped structure, and two sides of the guiding force-dividing frame are provided with a guide groove 29 and a fixed pulley 30 for guiding the loading rope 27;

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 axis of the upper slide rail 26 and the central axis of the lever 14 are arranged in parallel; the lever 14 is arranged in parallel with the main shaft 6, the middle part of the lever is arranged at the top of the fulcrum frame 13 in a swinging way through a hinge seat 31, one end of the lever is hinged with a hoisting seat 33 through a rotating shaft 32, and the other end of the lever is connected with a guide rope 17; the axis of oscillation of the lever 14 is parallel to the longitudinal axis; the top end of the hoisting 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 positioned in the same vertical plane; the bottom end of the hoisting seat 33 is provided with a roller 34 which is 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 is positioned in the same vertical plane;

the two loading ropes 27 are parallel and are in a closed loop structure, the tops of the two loading ropes 27 are hung on the rollers 34, the bottoms of the two loading ropes 27 are sleeved on the outer peripheral side of the loading base plate 10, and the middle parts of the two loading ropes are guided by the guide grooves 29 and the fixed pulleys 30 of the guide force-dividing frame 12 and the fixed pulleys 30 on the two sides of the loading base plate 10; during the loading process, the two loading ropes 27 are in a tight state, and can transmit the loading force generated by the lever 14 to the loading base plate 10; two loading ropes 27 with the same length are adopted, so that the laser beams emitted by the third laser 37 just pass through the middle of the two loading ropes 27, and the blocking of the laser beams by the loading ropes 27 is avoided;

the bottom end of the guide rope 17 bypasses the guide seat 15 and is connected with a weight 16 for loading;

the guide seat 15 is fixedly arranged on the base 1 and positioned at the bottom of the other end of the lever 14, two fixed pulleys rotating around a horizontal axis are arranged in the guide seat, and the middle part of the guide rope 17 is controlled by the two fixed pulleys to extend along the horizontal direction; the central axes of the two fixed pulleys mounted inside the guide holder 15 are arranged in parallel and may be arranged in parallel with the longitudinal axis, so that the guide rope 17 is wound around the portion between the two fixed pulleys inside the guide holder 15 and is parallel with 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;

the vertical rod is positioned at the outer side of the adjustable outer rail 8, and the cross rod 40 is positioned at the top side of the lever 14; as shown in the structure of fig. 1, two adjustable outer rails 8 are respectively arranged on two sides of a main shaft 6, and a vertical rod is respectively arranged outside each adjustable outer rail 8, and the vertical rods are respectively a first vertical rod 38 and a second vertical rod 39; a cross bar 40 is arranged at the top of the lever 14;

light holes 41 which penetrate through in the vertical direction are formed in the hoisting seat 33, the rotating shaft 32, the rolling shaft 34, the upper sliding rail 26 and the guiding force-dividing frame 12 and are used for transmitting vertical laser beams emitted by the third laser 35;

light holes 41 which penetrate along the longitudinal axis are formed in the adjustable outer rail 8, the loading outer frame 9 and the rotating shaft which is used for rotatably connecting the adjustable outer rail 8 and the loading outer frame 9, and are used for transmitting horizontal laser beams emitted by the first laser 35 and the second laser 36.

The testing machine is provided with light holes 41 on the parts corresponding to the light path of the laser, and the rotating shaft and the rolling shaft adopted in the loading device can adopt a cylindrical pin shaft with a through hole in the middle so as to form the light holes 41; when calibration is carried out, the laser is started, the position of the loading device is adjusted, laser generated by the first laser 35 and the second laser 36 passes through the adjustable slide rail 8, the loading outer frame 9 and the light hole 41 of the rotating shaft arranged between the adjustable slide rail 8 and the loading outer frame 9, so that the laser irradiates on the circumferential surface of the friction ring 19 to form a light spot, the light spot is ensured to be in the middle position of the circumferential surface, and the rotating shaft of the loading device can be ensured to pass through the axial center and the radial center of the friction ring 19; the position of the lever 14 is adjusted, so that laser generated by the third laser 37 penetrates through the hoisting base 33, the rotating shaft 32, the rolling shaft 34, the upper sliding rail 26 and the light-transmitting hole 41 of the guide force-dividing rod 12, the laser forms a light spot on the circumferential surface of the friction ring, the light spot is ensured to be in the middle position of the circumferential surface of the friction ring, and accurate loading of loading force can be ensured. By adopting the structure, the loading device can synchronously swing around the axis of the main shaft 6 along with the rotating frame 7, the position of the loading device is calibrated through the laser beam emitted by the laser before the test, and the loading device can synchronously swing around the longitudinal axis along with the loading outer frame 9 in the loading process, so that the linear contact friction pair and the loading device synchronously move, the acting force applied by the loading device just passes through the friction contact position of the friction ring 19 and the friction plate 25, and the accuracy of the test result is further improved.

Specifically, the detection device further includes a sensor mount 20 and a frictional force sensor 21; the sensor support 20 is fixedly arranged on the base 1; the sensor support 20 can be in an L-shaped structure, the top end of the sensor support is provided with a small hole for installing the friction force sensor 21, and the friction force sensor 21 is fixedly installed at the top of the sensor support 20, is connected with the rotating frame 7 and is used for detecting the friction force transmitted by the rotating frame 7; the friction force sensor 21 can be connected with the rotating frame 7 through a T-shaped plate, and when the rotating frame 7 is subjected to the friction force transmitted by the friction plate 25, the friction force sensor 21 generates a corresponding deformation signal due to the pulling force; the positive pressure sensor 22 is fixedly installed on the top surface of the loading base plate 10 and is used for detecting the positive pressure applied to the loading platform 11 by the loading base plate 10; when the loading base plate 10 is subjected to a loading force, the loading base plate 10 slides upwards 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 generates a deformation signal due to the corresponding extrusion deformation caused by the loading force; the control device is in signal connection with a friction sensor 21 and a positive pressure sensor 22.

Since the detecting means includes the friction sensor 21 and the positive pressure sensor 22, the friction sensor 21 is fixedly installed between the sensor support 20 and the turret 7, and the positive pressure sensor 22 is fixedly installed on the top surface of the loading baseplate 10, 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 means can be detected by the positive pressure sensor 22.

On the basis of the various embodiments, the testing machine further comprises a display device in signal connection with the control device and a rotating speed sensor installed on the motor 4; the display device and the control device may be of unitary construction; and according to the signals acquired by the control device, the display device is used for displaying the working state information of the motor 4 and the numerical values acquired by the friction force sensor 21 and the positive pressure sensor 22. The rotation speed sensor is in signal connection with the control device and is used for detecting the rotation speed of the motor 4.

The display device is convenient for displaying various working parameters and collected parameters of the testing machine; the rotational speed of the motor 4 can be detected conveniently by means of a rotational speed sensor and the relative speed between the friction plate 25 and the friction ring 19 can be monitored and regulated by means of a rotational speed sensor and a control device.

In the test process of the tester, the loading force is transmitted to the loading base plate 10 through the loading rope 27, the loading base plate 10 moves upwards along the sliding guide rail because of being limited by the sliding guide rail of the loading outer frame 9, and the positive pressure sensor 22 moves along with the loading base plate 10, so that the loading platform 11 is pushed to move upwards. The lubricant sump 18 is fixed to the loading platform 11 and moves upward with the loading platform 11. Because the friction plate 25 is located at the inner bottom of the lubricating oil groove 18, the friction plate 25 moves upwards along with the lubricating oil groove 18, after the end face of the friction plate 25 is tangent to and completely attached to the outer peripheral face of the friction ring 19, the loading bottom plate 10 cannot move upwards any more, the friction pair is subjected to corresponding loading force, the friction pair is in a line contact state, and the loading process is completed. When the peripheral surface of the friction ring 19 is not tangent to the end surface of the friction plate 25 due to external factors, the friction pair is out of a linear contact state, a certain included angle appears between the corresponding binding surfaces, and a rotation moment is formed between the two planes; because the friction ring 19 is a fixed structure, the rotating torque finally acts on the loading device, so that the loading outer frame swings around the rotating shaft in the direction of reducing the included angle of the binding surface, and the end surface of the friction plate 25 correspondingly swings along with the loading outer frame; when the outer peripheral surface of the friction ring 19 is again brought into contact with the end surface of the friction plate 25, the rotational moment acting between the two planes disappears, and the friction pair resumes the line contact state. When the motor 4 operates, the friction ring 19 rotates along with the spindle 6, the outer circumferential surface of the friction ring 19 and the end surface of the friction plate 25 are always tangent under the action of the restoring moment, and therefore the friction ring 19 and the friction plate 25 are always in a stable linear contact state.

The constant line contact friction between the friction ring 19 and the friction plate 25 can be realized by adopting the testing machine. On the basis, the rotating speed of the friction ring 19 is controlled by adjusting the rotating speed of the motor 4, the positive pressure is controlled by controlling the mass of the weight 16 of the loading device, so that the friction and wear conditions of the linear contact friction pair under different rotating speeds and different positive pressure conditions are detected, and the accuracy of the test result is improved.

In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a line contact friction wear test machine with calibration function which characterized in that includes:

a base;

a main shaft supported on the top of the base along the horizontal direction;

2. The testing machine of claim 1, wherein the laser calibration device comprises three lasers and a laser mount;

the vertical rods and the cross rods are respectively provided with the laser;

3. The testing machine of claim 2, wherein the drive means comprises a motor, a drive belt, a bushing, a support plate, and a turret;

the shaft sleeve is fixedly arranged on the base through the supporting plate;

4. The testing machine of claim 3, wherein the loading device comprises two adjustable outer rails, a loading outer frame, a loading base plate, a loading platform, a guiding force-dividing frame, an upper sliding rail, a fulcrum frame, a lever, a guide seat, a weight, a guide rope and a loading rope;

the central axis of the lever and the axial lead of the main shaft are positioned in the same vertical plane, and the central line of the upper sliding rail and the central axis of the lever are arranged in parallel; the lever is arranged in parallel with the main shaft, the middle part of the lever is arranged at the top of the fulcrum frame through a hinge seat in a swinging manner, one end of the lever is hinged with a hoisting seat through a rotating shaft, and the other end of the lever is connected with the guide rope; the swing axis of the lever is parallel to the longitudinal axis; the top end of the hoisting seat can swing around the axis of the rotating shaft, and the axis of the rotating shaft is parallel to the longitudinal axis and is positioned in the same vertical plane; a rolling shaft is arranged at the bottom end of the hoisting seat, and the axis of the rolling shaft is parallel to the axis of the main shaft and is positioned in the same vertical plane;

the two loading ropes are parallel and are of a closed-loop structure, the top of each loading rope is suspended on the corresponding rolling shaft, the bottom of each loading rope is sleeved on the outer peripheral side of the corresponding loading bottom plate, and the middle of each loading rope is guided through the guide groove and the fixed pulley of the corresponding guide force-dividing frame and the fixed pulleys on the two sides of the corresponding loading bottom plate;

5. The testing machine of claim 4, wherein the detection device further comprises a sensor mount and a friction sensor;

the sensor support is fixedly arranged on the base;

6. The testing machine of claim 5, further comprising a display device in signal connection with the control device and a rotational speed sensor mounted to the motor;

the rotating speed sensor is in signal connection with the control device and used for detecting the rotating speed of the motor.

7. The testing machine of any one of claims 1 to 6, wherein the end face of the spindle is provided with a threaded bore;

the friction ring is mounted on the main shaft through a first locking bolt;

the friction plate can be reused by rotating.

8. The testing machine of any one of claims 3 to 6, wherein the motor is fixedly mounted at the bottom of the base, and a rubber gasket is clamped between the motor and the base;

the base is provided with a notch for the transmission belt to pass through.