CN111999061A

CN111999061A - Axial loading device for bearing test

Info

Publication number: CN111999061A
Application number: CN202011018520.7A
Authority: CN
Inventors: 余永健; 司东宏; 李明岩; 于海晓
Original assignee: Henan University of Science and Technology
Current assignee: Henan University of Science and Technology
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2020-11-27

Abstract

The invention provides an axial loading device for a bearing test, which comprises a damping unit, a loading unit, a clutch unit and a test bearing unit, wherein the clutch unit arranged in the axial loading device can realize that an axial loading mechanism is quickly separated from a test bearing when a test bearing roller is glued with an outer ring at a high temperature, and is loaded in a mode of a linear actuator, a lever and a permanent magnet, so that the aim of accurately and continuously adjusting the axial force applied to the test bearing in a larger range is fulfilled.

Description

Axial loading device for bearing test

Technical Field

The invention belongs to the technical field of bearing test equipment, and particularly relates to an axial loading device for a bearing test.

Background

The rolling bearing is widely applied to various mechanical equipment with remarkable advantages, the motion precision of the rolling bearing determines the precision and the performance of mechanical equipment, but the rolling bearing is one of the most prone to failure key parts in the mechanical equipment. There are many failure modes of the bearing, with the failure mode due to slippage accounting for the highest proportion of total failure; when the rolling bearing slides in operation, not only the friction coefficient is increased, but also a large amount of heat is generated, which influences the movement precision and the mechanical efficiency of the rolling bearing, and simultaneously reduces the service life of the rolling bearing. The occurrence of the slipping phenomenon of the rolling bearing can be effectively prevented by applying proper axial preload. In the research and development design and test of the bearing, the rolling bearing generates different degrees of skidding by changing the magnitude of the applied axial preload, the damage behavior of the working surface of the rolling bearing under different rolling-skidding ratios can be simulated, and a scientific basis is provided for the design and application of the bearing.

At present, most of the axial loading devices in the existing bearing test adopt springs to apply preload to the test bearing, or realize the axial loading to the test bearing through a hydraulic mechanism; when the spring is adopted to apply preload to the test bearing, because the spring has errors during manufacturing, accurate control cannot be carried out during loading, and equal axial force can not be applied to the test bearing by each spring; the loading force can be accurately controlled by using the loading of the hydraulic mechanism, but the hydraulic mechanism needs a set of complex hydraulic system; and when the outer ring of the test bearing and the roller are subjected to high-temperature gluing, the axial loading device used in the existing bearing test cannot be separated from the test bearing in time, so that the test result is influenced.

Disclosure of Invention

In order to solve the problem that the axial load is continuously and accurately adjusted within a certain range in a bearing test, the invention provides an axial loading device for the bearing test, aiming at the problem that the axial loading device adopted in the existing bearing test cannot be separated from a test bearing in time when the outer ring of the test bearing is glued with a roller at high temperature, and a clutch unit is arranged in the axial loading device; in order to avoid applying axial force to the test bearing by the gravity of the bearing seat cover and the outer ring of the test bearing, a lever mechanism is arranged in the axial loading device; aiming at the problem that the vibration generated in the test process influences the accurate quantitative loading of the axial force, a variable damping unit is arranged.

In order to achieve the purpose, the invention adopts the technical scheme that: an axial loading device for bearing test comprises,

the test bearing unit is used for mounting and supporting a test bearing, and a guide sleeve is arranged on the outer side of the top end of the test bearing unit;

the clutch unit comprises a bearing seat cover and a clutch, wherein the bearing seat cover is covered on the outer side of the test bearing and is used for applying axial loading force to the test bearing, the clutch is in sliding connection with the guide sleeve, a magnetic clutch mechanism which is matched with the bearing seat cover is arranged between the bearing seat cover and the clutch, and the bearing seat cover and the clutch can be connected in a closing mode when the clutch slides upwards along the outer wall of the guide sleeve;

the loading unit comprises a shifting fork arranged on the outer side of the clutch unit and a driving mechanism capable of driving the shifting fork to move up and down, the shifting fork is fixedly connected with the clutch, and the driving mechanism drives the clutch unit after being attracted to move down through the shifting fork so as to apply axial loading force to the test bearing;

and the damping unit is adjustable in damping and connected to one end of the shifting fork, and is used for slowing down vibration generated in the process that the shifting fork moves up and down.

Further, still include lever mechanism, this lever mechanism is including being used for installing fixed fork seat and the balance bolt of a plurality of detachable connection in shift fork one end to this axial loading device, the both ends of fork seat are connected to two fork arms of shift fork through the cylindric lock respectively, and the cylindric lock still is provided with bearing with the junction of shift fork arm, the balance bolt through installing a certain amount in the one end of shift fork is adjusted the height of the shift fork other end, in order to offset the axial force of being applyed to test bearing by the gravity of bearing housing lid and test bearing outer lane.

Furthermore, the magnetic clutch mechanism is composed of a plurality of armatures and a plurality of permanent magnets which are correspondingly arranged on the opposite end faces of the bearing seat cover and the clutch and are matched with each other, the permanent magnets are evenly distributed on the end face of the clutch along the circumferential direction, and the bottom of each permanent magnet is provided with an adjusting screw for adjusting the height of the permanent magnet.

Furthermore, the guide sleeve and the clutch are coaxially arranged and are in sliding connection through a linear bearing.

Further, the damping unit includes solid axle, hollow shaft and two circular slabs that the structure is the same and set up from top to bottom, has all seted up a plurality of convex through-holes on the terminal surface of each circular slab, and wherein, the circular slab that is located the bottom is connected to the one end of shift fork through solid hub connection, and the outside cover of solid axle is equipped with the bottom of hollow shaft and hollow shaft be connected to the circular slab that is located the top, through rotating the hollow shaft, adjusts the position relation of the convex through-hole on two circular slabs, and then realizes adjusting the damping of damping unit.

Furthermore, actuating mechanism includes pull rod, pull rod guide frame, linear actuator, extension spring and dynamometry pole, the pull rod slides and sets up in the pull rod guide frame, linear actuator is connected with the pull rod lower extreme and can drives the pull rod linear motion about in the pull rod guide frame, the extension spring lower extreme links to each other with the pull rod upper end, the extension spring upper end with the dynamometry pole lower extreme is connected, the upper end of dynamometry pole is connected to the shift fork.

Furthermore, the bearing seat cover is made of a non-ferromagnetic material, the armature is made of a ferromagnetic material, and threads matched with the bearing seat cover are arranged on the armature.

Further, the test bearing unit comprises a test bearing, a shaft and a conical screw, wherein a threaded through hole matched with the threaded part of the conical screw is axially formed in the shaft, a conical hole communicated with the threaded through hole is formed in the top end of the shaft, a plurality of cuboid notches are formed in the conical hole along the bus direction, the end of the conical screw is provided with an inclined plane, the conical screw is continuously screwed into the threaded through hole, the shaft is expanded at the conical hole, and the test bearing is loaded.

Furthermore, the test bearing is an angular contact ball bearing, the narrow end of the outer ring of the test bearing is in contact with a shaft shoulder of the shaft, and the wide end of the outer ring of the test bearing is in contact with a bearing seat cover.

Compared with the prior art, the invention has the beneficial effects that: the clutch unit can realize that when a roller of the test bearing is glued with an outer ring at high temperature, the axial loading mechanism is separated from the test bearing more quickly, and the linear actuator, the lever and the permanent magnet are loaded in a mode, so that the aim of accurately and continuously adjusting the axial force applied to the test bearing in a larger range is fulfilled.

Drawings

FIG. 1 is a schematic structural diagram of an axial loading device for bearing test according to the present invention;

FIG. 2 is a top view of the axial loading device for testing a bearing of the present invention;

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a schematic structural diagram of a shifting fork in the axial loading device for the bearing test of the present invention;

FIG. 5 is a schematic structural diagram of a fork seat in the axial loading device for bearing test according to the present invention;

FIG. 6 is a schematic structural diagram of a clutch in the axial loading device for bearing test according to the present invention;

FIG. 7 is a schematic structural diagram of a bearing seat cover of the axial loading device for testing a bearing of the present invention;

FIG. 8 is a schematic structural diagram of a central shaft of the axial loading device for bearing test according to the present invention;

FIG. 9 is a schematic structural view of an axial loading device for bearing test according to the present invention, in which an included angle between a top damping plate and a bottom damping plate is 0 degree;

FIG. 10 is a schematic structural view of an axial loading device for bearing test according to the present invention, in which an included angle between a top damping plate and a bottom damping plate is 22.5 degrees;

FIG. 11 is a schematic structural view of an axial loading device for bearing test according to the present invention, in which an included angle between a top damping plate and a bottom damping plate is 45 degrees;

reference numerals: 1. damping cylinder, 2, top damping plate, 3, bottom damping plate, 4, pull rod, 5, pull rod guide frame, 6, linear actuator, 7, tension spring, 8, force measuring rod, 9, shifting fork, 901, oblong through hole, 902, threaded through hole, 903, balance bolt, 904, round through hole, 10, shifting fork seat, 11, cylindrical pin, 12, needle bearing, 13, guide sleeve, 14, clutch, 1401, countersunk head threaded through hole, 15, linear bearing, 16, bearing seat cover, 17, armature, 18, permanent magnet, 1801, adjusting screw, 19, test bearing, 20, shaft, 21, conical screw, 22, fiber grating sensor, 23, cuboid notch, 24 and circular arc through hole.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments, and all other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the protection scope of the present invention.

An axial loading device for bearing tests is shown in figures 1-3 and comprises a damping unit, a loading unit, a clutch unit and a test bearing unit;

the damping unit comprises a bottom damping plate 3, a top damping plate 2 and a damping oil cylinder 1, wherein the bottom damping plate 3 comprises a first circular plate and a solid shaft which is coaxially arranged with the first circular plate, the top damping plate 2 comprises a second circular plate and a hollow shaft which is coaxially arranged with the second circular plate, the diameter of the hollow shaft is larger than that of the solid shaft, the length of the hollow shaft is smaller than that of the solid shaft, and four arc-shaped through holes with the same size are uniformly distributed on the two circular plates along the circumferential direction; the top damping plate 2 is arranged above the bottom damping plate 3 and is in tight fit with the bottom damping plate 3, so that the top damping plate 2 can rotate around the central axis of the bottom damping plate 3 in the circumferential direction under the action of external force; change the size of long circular arc through-hole overlap portion through rotatory top layer damping plate 2, and then change the damping of damping plate in fluid, specifically: when the two circular arc-shaped through holes 24 are not overlapped, as shown in fig. 11, the damping is maximum; when half of the two circular arc-shaped through holes 24 are overlapped, as shown in fig. 10, the damping is half of that when the two circular arc-shaped through holes are completely overlapped; when the two circular arc-shaped through holes 24 completely overlap, as shown in fig. 9, the damping is minimal. And injecting a certain amount of liquid into the damping oil cylinder, placing the lower ends of the two damping plates which are coaxially installed in the damping oil cylinder 1, and connecting the lower ends of the two damping plates to a shifting fork 9 in the loading unit through the bottom damping plate 3 and the solid shaft.

The loading unit comprises a pull rod 4, a pull rod guide frame 5, a linear actuator 6, an extension spring 7, a force measuring rod 8 and a fiber grating sensor 22, wherein the pull rod 4 is arranged in the pull rod guide frame 5, the linear actuator 6 is connected with the lower end of the pull rod 4 and drives the pull rod 4 to move linearly up and down in the pull rod guide frame 5, the lower end of the extension spring 7 is connected with the upper end of the pull rod 4, the upper end of the extension spring 7 is connected with the lower end of the force measuring rod 8, a shifting fork 9 is connected with the upper end of the force measuring rod 8, and the fiber grating sensor 22 for measuring axial force is pasted on the force measuring rod 8.

As shown in fig. 4-6, two threaded through holes are formed in a fork handle of a fork 9, an oblong through hole 901, a circular through hole 904 and a threaded through hole 902 are formed in a fork arm, the threaded through hole 902 formed in the fork handle is connected to the upper end of a force measuring rod 8 and the upper end of a bottom damping plate 3, a cylindrical pin 11 is installed in the oblong through hole 901 and connected to a clutch 14 and the fork 9 through the cylindrical pin 11, a needle bearing 12 is installed at the circular through hole 904 on the fork arm, two ends of a fork base 10 are installed at an inner ring of the needle bearing 12 through the cylindrical pin 11, the fork base 10 is fixedly installed on a bearing test device through a bolt, a balance bolt is installed at the threaded through hole 902 on the right side of the fork arm, and the balance bolt and the fork base 10 form a lever mechanism in the present invention, which the principle is as follows: the height of the other end of the shifting fork is adjusted by installing a certain number of balance bolts at one end of the shifting fork, so that the axial force applied to the test bearing by the gravity of the bearing seat cover and the outer ring of the test bearing is offset.

The clutch unit comprises a guide sleeve 13, a clutch 14, a linear bearing 15, a bearing seat cover 16, an armature 17 and a permanent magnet 18, wherein the armature 17 and the permanent magnet 18 are made of ferromagnetic materials, the guide sleeve 13 is arranged in a shifting fork arm of a shifting fork 9 and is arranged above a bearing test device, two round holes with the same size are formed in the side face of the clutch 14, the round holes are connected with the shifting fork 9 through a cylindrical pin 11, the clutch 14 and the shifting fork 9 are concentrically arranged on the outer side of the guide sleeve 13, and a gap is radially reserved between the clutch 14 and the shifting fork 9, as shown in fig. 7, three countersunk head thread through holes 1401 are respectively formed in the four corners of the top face of the clutch 14, and axial; the bearing seat cover 16 is made of non-ferromagnetic materials, so that the test bearing can be protected, and the test bearing is prevented from being magnetized to adsorb particles, so that the abrasion of the test bearing is aggravated, and the test result is influenced; the linear bearing 15 is concentrically arranged between the clutch 14 and the guide sleeve 13, the bearing seat cover 16 is arranged above the clutch 14 and is concentric with the clutch 14, and a certain interval is reserved between the bearing seat cover 16 and the clutch 14 in the vertical direction, so that when the shifting fork 9 is lifted upwards, the clutch 14 can be driven to move upwards; the four threaded through holes 902 arranged on the bearing seat cover 16 are respectively provided with the armatures 17, the armatures 17 are provided with threads, the permanent magnets 18 are arranged in the countersunk threaded through holes 1401, the adjusting screws 1801 are arranged below the permanent magnets 18 and are connected with the clutch 14, and the distance between each permanent magnet 18 and each armature 17 is adjusted by rotating the screws so that the magnetic force between each permanent magnet 18 and each armature 17 is equal; when the permanent magnet 18 needs to be taken out, the adjusting screw 1801 is rotated to eject the permanent magnet 18 downward and upward.

The test bearing unit comprises a test bearing 19, a shaft 20 and a conical screw 21, as shown in fig. 8, a threaded through hole matched with the threaded part of the conical screw 21 is axially formed in the shaft 20, a conical hole communicated with the threaded through hole is formed in the top end of the shaft, a plurality of cuboid notches are formed in the conical hole along the bus direction, an inclined plane is formed in the end part of the conical screw, the conical screw is continuously screwed into the threaded through hole, the shaft expands at the conical hole, the shaft 20 and the test bearing 19 are in transition fit, the test bearing is loaded, and the conical screw 21 can be screwed out when the test bearing 19 needs to be replaced or the test bearing 19 needs to be dismounted.

The working principle of the axial loading device is as follows: the axial loading device is arranged on bearing test equipment through a shifting fork seat 10, and a test bearing 19 is concentrically arranged in a bearing seat cover 16; lifting the shifting fork 9 to enable the clutch 14 to move upwards, reducing the air gap between the permanent magnet 18 and the armature 17, enabling the clutch and the bearing seat cover 16 to attract each other through magnetic force, and enabling the spring 7 to be in a stretching state; adjusting a balance bolt 903 at the right end of the shifting fork to enable the shifting fork 9 to be in a balanced state, and offsetting the axial force exerted on the test bearing 19 by the gravity of the bearing seat cover 16 and the outer ring of the test bearing 19; starting the linear actuator 6 to enable the pull rod 4 to drive the shifting fork 9 to move downwards, driving the bearing seat cover 16 to move downwards by the clutch 14 connected with the shifting fork 9 under the action of the magnetic force of the permanent magnet 18, and applying an axial force to the test bearing 19 by the downward movement of the bearing seat cover 16; vibrations generated during the application of the axial force may be damped by the damping unit; the applied axial force is measured by the fiber grating sensor 22 and transmitted to the computer, ensuring that the magnetic force between the permanent magnet 18 and the armature 17 is always greater than the applied axial force; starting a motor to drive the test bearing 19 to rotate, wherein the inner ring of the test bearing 19 rotates at the moment, and the outer ring is static; along with the increase of the rotating speed of the motor for rotating the driving shaft, the temperature between the roller of the test bearing 19 and the inner and outer roller paths can be increased; when the temperature reaches a certain value, the roller of the test bearing is glued with the inner raceway and the outer raceway at high temperature, and the roller drives the outer ring of the test bearing to rotate; when the rotating torque generated by the rotation of the outer ring of the test bearing is larger than the shearing torque between the permanent magnet and the armature, the permanent magnet 18 in the clutch 14 and the armature 17 in the bearing seat cover 16 are staggered with each other, so that the magnetic force of the mutual attraction between the clutch 14 and the bearing seat cover 16 disappears; under the action of the resilience force of the extension spring 7 and the applied axial force, the shifting fork 9 drives the clutch 14 to move downwards and return to the initial position; the clutch 14 disengages from the bearing block cover 16 and relieves the axial force exerted by the test bearing 19.

The working process of the invention is as follows:

the shifting fork 9 is lifted upwards, the clutch 14 is moved upwards linearly under the action of the linear bearing 15, the air gap between the permanent magnet 18 and the armature 17 is reduced, and the permanent magnet 18 in the clutch 14 and the armature 17 in the bearing seat cover 16 are attracted mutually through magnetic force; and adjusting a balance bolt 903 at the right end of the shifting fork 9 to enable the shifting fork 9 of the clutch unit to be in a balanced state, offsetting the axial force applied to the test bearing 19 by the gravity of the bearing seat cover 16 and the outer ring of the test bearing 19, and enabling the tension spring 7 in the loading unit to be in a tension state at the moment.

Starting the linear actuator 6 to drive the pull rod 4 to move linearly in the pull rod guide frame 5, so that the shifting fork 9 tends to move downwards, the clutch 14 connected with the shifting fork 9 drives the bearing seat cover 16 to move downwards under the action of the magnetic force of the permanent magnet 18, and the bearing seat cover 16 drives the outer ring of the test bearing 19 to move downwards so as to apply axial force to the test bearing 19; the vibration generated in the process of applying the axial force can be reduced by the damping unit, and the size of the overlapped part of the long circular arc-shaped through hole can be changed by rotating the top damping plate 2, so that the damping of the damping plate in oil liquid is changed; the applied axial force is measured by the fiber grating sensor 22 and transmitted to the computer, and quantitative and accurate loading of the axial force is adjusted and completed by observing data transmitted to the computer, and at the moment, the axial pre-tightening force of the test bearing 19 is applied.

Starting a motor to drive the test bearing 19 to rotate, wherein the inner ring of the test bearing 19 rotates at the moment, and the outer ring is static; along with the increase of the rotating speed of the motor, the temperature between the roller of the test bearing 19 and the inner and outer raceways will increase; when the temperature rises to a certain value, the roller of the test bearing 19 and the inner and outer raceways can generate a high-temperature gluing phenomenon, and the roller drives the outer ring of the test bearing 19 to rotate; when the rotating torque generated by the rotation of the outer ring of the test bearing 19 is larger than the shearing torque between the permanent magnet 18 and the armature 17, the armature 17 in the bearing seat cover 16 and the permanent magnet 18 in the clutch 14 are staggered with each other, and the magnetic force between the two disappears; the shifting fork 9 drives the clutch 14 to rapidly move downwards under the resilience of the tension spring 7 and the downward axial force exerted by the linear actuator 6, the clutch 14 and the bearing block cover 16 are separated from each other, and the exerted axial pre-tightening force is unloaded.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An axial loading device for bearing test is characterized by comprising,

2. The axial loading device for the bearing test is characterized by further comprising a lever mechanism, wherein the lever mechanism comprises a shifting fork seat and a plurality of detachable balance bolts, the shifting fork seat is used for fixedly mounting the axial loading device, the balance bolts are detachably connected to one end of a shifting fork, two ends of the shifting fork seat are respectively connected to two shifting fork arms of the shifting fork through cylindrical pins, needle bearings are further arranged at the joints of the cylindrical pins and the shifting fork arms, and the balance bolts are mounted at one end of the shifting fork in a certain number to adjust the height of the other end of the shifting fork so as to counteract the axial force applied to the test bearing by the gravity of a bearing seat cover and an outer ring of the test bearing.

3. The axial loading device for the bearing test is characterized in that the magnetic clutch mechanism consists of a plurality of armatures and a plurality of permanent magnets which are correspondingly arranged on opposite end faces of the bearing seat cover and the clutch and are matched with each other, the permanent magnets are uniformly distributed on the end face of the clutch along the circumferential direction, and an adjusting screw for adjusting the height of each permanent magnet is arranged at the bottom of each permanent magnet.

4. The axial loading device for the bearing test is characterized in that the guide sleeve and the clutch are coaxially arranged and are in sliding connection through a linear bearing.

5. The axial loading device for the bearing test according to claim 1, wherein the damping unit comprises a solid shaft, a hollow shaft and two circular plates which are identical in structure and are arranged up and down, a plurality of circular arc-shaped through holes are formed in the end face of each circular plate, the circular plate located at the bottom is connected to one end of the shifting fork through the solid shaft, the hollow shaft is sleeved on the outer side of the solid shaft, the bottom end of the hollow shaft is connected to the circular plate located at the top, the position relation of the circular arc-shaped through holes in the two circular plates is adjusted by rotating the hollow shaft, and accordingly the damping of the damping unit is adjusted.

6. The axial loading device for the bearing test is characterized in that the driving mechanism comprises a pull rod, a pull rod guide frame, a linear actuator, an extension spring and a force measuring rod, the pull rod is slidably arranged in the pull rod guide frame, the linear actuator is connected with the lower end of the pull rod and can drive the pull rod to linearly move up and down in the pull rod guide frame, the lower end of the extension spring is connected with the upper end of the pull rod, the upper end of the extension spring is connected with the lower end of the force measuring rod, and the shifting fork is connected with the upper end of the force measuring rod.

7. The axial loading device for bearing test as claimed in claim 1, wherein the bearing seat cover is made of non-ferromagnetic material, the armature is made of ferromagnetic material, and the armature is provided with a thread which is matched with the bearing seat cover for installation.

8. The axial loading device for the bearing test as claimed in claim 1, wherein the test bearing unit comprises a test bearing, a shaft and a conical screw, a threaded through hole matched with the threaded part of the conical screw is axially formed in the shaft, a conical hole communicated with the threaded through hole is formed in the top end of the shaft, a plurality of cuboid notches are formed in the conical hole along the direction of a bus, an inclined plane is formed in the end part of the conical screw, and the conical screw is continuously screwed into the threaded through hole to expand the shaft at the conical hole, so that the test bearing is loaded.

9. The axial loading unit for bearing testing as claimed in claim 8, wherein the test bearing is an angular contact ball bearing having an outer race narrow end in contact with a shaft shoulder of the shaft and an outer race wide end in contact with a bearing housing cap.