CN108254183A - Crank connecting link loads the rolling bearing fatigue life test system of radially alternating load - Google Patents

Abstract

The invention relates to a rolling bearing fatigue life testing system with a radial alternating load loaded on a crank connecting rod. The system controls the rotation of the drive motor through a computer to drive the rolling bearing to rotate. In the radial alternating load loading unit of the crank connecting rod, the crank The connecting rod transmission mechanism converts the rotary motion of the rotary motor into linear motion, which can affect the stretching/compression of the spring. Due to the change of the stretching/compression of the spring, the spring will be able to exert different sizes and variable directions on the surface of the movable fixture. The force of the bearing can be loaded by adding multiple radial alternating load loading units of crank connecting rods in different areas of the movable fixture. The torque meter and temperature sensor are used to detect the performance of the rolling bearing during operation. Compared with the prior art, the invention can simply, conveniently and accurately realize the radial alternating load loading of the rolling bearing, and carry out the fatigue life test of the rolling bearing in combination with the real working conditions of the internal combustion engine.

Description

Fatigue life test system for rolling bearings with alternating radial loads on the crank connecting rod

technical field

The invention belongs to the field of life testing of engine rolling bearings, and relates to a rolling bearing fatigue life testing system in which crank connecting rods are loaded with radial alternating loads.

Background technique

Internal combustion engines are widely used in automobiles, ships, airplanes, tanks, railway locomotives, agricultural machinery, construction machinery, generator sets and other industries. As power equipment, they occupy a very important position in the national economy. The internal combustion engine includes several important friction pairs such as piston-cylinder liner, piston ring-cylinder liner, crankshaft-bearing and cam-tappet. Among them, the crankshaft bearing, including the main bearing and the connecting rod bearing (due to the working load of this type of bearing The size and direction of the internal combustion engine change with time, so it is usually called a dynamic load bearing), which is one of the most critical friction pairs of the internal combustion engine. It not only affects the reliability and fatigue life of the internal combustion engine, but also affects the potential for further strengthening of the internal combustion engine.

At present, the main bearings, camshaft bearings and connecting rod big end bearings of automobile engines mainly use sliding bearings, and the camshaft bearings of a few engines use rolling bearings. According to the theory of tribology, the energy loss of rolling friction is about an order of magnitude smaller than that of sliding friction. Therefore, under the same working conditions, the friction loss of rolling bearings is much smaller than that of sliding bearings, so bearing rolling has become an important attempt to reduce friction and consumption of engines.

The fatigue life and reliability of rolling bearings are the most important performance indicators of rolling bearings. However, due to too many factors affecting fatigue life and the theory of bearing fatigue life still needs to be perfected, life testing is the only effective way at present. Bearing test is an important verification process that is indispensable in the bearing design and manufacturing process. The load of the test bearing is an important parameter in the test of the bearing testing machine, and its accuracy directly affects the test results of the bearing. At present, the traditional rolling bearing test system has single loading characteristics and cannot realize variable load loading. In real internal combustion engines, dynamic rolling bearings are often under alternating loads. Therefore, it is difficult for traditional rolling bearing test systems to carry out fatigue life tests of engine dynamic rolling bearings.

Contents of the invention

The object of the present invention is to provide a rolling bearing fatigue life testing system with a crank connecting rod loaded with radial alternating loads in order to overcome the above-mentioned defects in the prior art.

The purpose of the present invention can be achieved through the following technical solutions:

A rolling bearing fatigue life testing system loaded with radial alternating loads on a crank connecting rod, used to measure the fatigue life of rolling bearings under radial alternating loads, the rolling bearings are composed of outer rings, inner rings and cages Composed of multiple rolling elements between the inner and outer rings, the system includes,

working platform,

drive motor, connected to the working platform,

The rotating shaft is connected with the drive motor, and the rotating shaft is provided with a torque meter,

Two fixing fixtures are connected on the working platform, and each fixing fixture holds a test rolling bearing inside,

The movable fixture is located between two fixed fixtures and is composed of two opposing movable sub-fixtures. The movable fixture holds at least one rolling bearing to be tested, and the rolling bearing to be tested and the rolling bearing to be tested are arranged coaxially. , and are set on the rotating shaft,

The temperature sensor is set in the movable fixture and is in contact with the tested rolling bearing,

The crank connecting rod radial alternating load loading unit is composed of four loading components acting on the movable fixture. Each loading component is composed of a rotating motor connected in sequence, a crank connecting rod transmission mechanism, a load loading spring and a connector. The above-mentioned connector is connected with the movable fixture, and the load-loading springs of the four loading components are arranged in the shape of a "ten", and the expansion and contraction direction of each load-loading spring is in the radial direction of the rotating shaft, and the crank-connecting rod transmission The mechanism is composed of a rotating wheel, a rocker and a reciprocating rod that are sequentially connected by transmission. The reciprocating rod is passed through a sleeve fixed on the working platform, and is slidably connected with the sleeve in the direction of expansion and contraction of the load-loaded spring. The free end of the reciprocating rod is connected with the load-loading spring through the connecting plate, and the running wheel is connected with the rotating motor in transmission.

Preferably, the runner is a gear-type runner, and the output shaft of the rotary motor is connected with a worm matching the gear of the runner, and the runner is connected to the rotary motor through the worm.

Preferably, the runner is provided with a plurality of eccentric rocker connection positions in the radial direction, the rocker is hingedly connected to the reciprocating rod head to tail in sequence, and the free end of the rocker is connected to the rocker alternatively bit hinged connection.

Preferably, two rolling bearings to be tested are clamped in the movable fixture.

Preferably, the movable fixture is composed of an upper movable sub-fixture and a lower movable sub-fixture facing up and down, the bottom of the upper movable sub-fixture is provided with an upper arc groove, and the top of the lower movable sub-fixture is provided with There is a lower arc-shaped groove, and the upper arc-shaped groove and the lower arc-shaped groove cooperate to form a clamping part that matches the rolling bearing. The crank connecting rod radial alternating load loading unit is composed of an upper loading assembly, a lower loading assembly, and a left loading assembly. component and the right loading component, the upper loading component is set above the upper movable sub-fixture and acts on the top of the upper movable sub-fixture, and the lower loading component is set under the lower movable sub-fixture and acts on the lower movable sub-fixture The bottom of the fixture, the left loading assembly is set on the left side of the movable fixture and acts on the connection between the upper movable sub-fixture and the lower movable sub-fixture, and the right loading component is set on the right side of the movable fixture and acts on the upper The connection between the movable sub-fixture and the lower movable sub-fixture.

Preferably, the temperature sensor is arranged in the upper arc groove or the lower arc groove, and is in contact with the outer ring of the rolling bearing.

Preferably, the above-mentioned rotating shaft is transmission-connected with the driving motor through a coupling.

Preferably, the system further includes a controller communicated with the driving motor, the temperature sensor, the torque meter and the rotating motor respectively.

Preferably, the system further includes an oil supply mechanism for providing lubricating oil for the rolling bearings to be tested and the rolling bearings to be tested, and the said oil supply mechanism is communicated with the controller.

The computer controls the rotation of the drive motor to drive the rolling bearing to run at a given speed. In the radial alternating load loading unit of the crank connecting rod, the rotation of the rotating motor is controlled by a computer, and the rotating motion of the rotating motor is converted into a linear motion through the crank connecting rod transmission mechanism, which can affect the tension/compression of the spring. Due to the change of the tension/compression of the spring, the spring will be able to exert a force of different magnitudes and variable directions on the surface of the movable fixture. The bearing alternating load can be realized by adding multiple crank connecting rod radial alternating load loading units in different regions of the movable fixture. The computer controls the oil supply during the operation of the rolling bearing through the oil supply mechanism, and the torque meter and temperature sensor can be used to detect the performance of the rolling bearing during operation.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The computer controls the rotation angle of the rotating motor, and then changes the compression/stretch of the spring to control the spring force, so that the alternating load of the rolling bearing in two relative directions (such as the up and down direction) can be realized.

(2) Combined with the real working conditions of the internal combustion engine, the loading of the real working condition load of the internal combustion engine can be realized by controlling the rotation angle of the rotating electrical machine and the variation of time through the computer. Using the test system is helpful to carry out the engine dynamic load rolling bearing fatigue life test.

(3) Through the crank-link mechanism, the alternating load can be loaded in one rotation direction of the rotary motor, which saves the step of changing the rotation direction of the rotary motor, and is simple and reliable.

(4) By providing a plurality of eccentric rocker connection positions in the radial direction on the runner, different levels of load loading can be achieved through a set of equipment.

(5) By setting the worm, self-locking can be realized, which avoids the influence of the reaction force of the load-loading spring on the load-loading accuracy and the running stability of the rotary motor.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a schematic diagram of the crank connecting rod radial alternating load loading unit of the present invention.

In the figure, 1 is the computer, 2 is the driving motor, 3 is the coupling, 4 is the torque meter, 5 is the fixed fixture A, 6 is the oil supply mechanism, 7 is the radial alternating load loading unit of the crank connecting rod, 8 is the Movable fixture, 81 is the upper movable sub-fixture, 82 is the lower movable sub-fixture, 9 is the fixed fixture B, 10 is the rotating shaft, 11 is the accompanying rolling bearing B, 12 is the tested rolling bearing B, 13 is the tested rolling bearing A, 14 15 is the working platform, 16 is the temperature sensor, 17 is the rotating motor A, 181 is the runner A, 182 is the rocker A, 183 is the reciprocating rod A, 184 is the sleeve A, 185 is the connecting plate A, 19 is load spring A, 20 is connector A, 21 is rotating motor B, 221 is runner B, 222 is rocker B, 223 is reciprocating rod B, 224 is sleeve B, 225 is connecting plate B , 23 is load spring B, 24 is connector B, 25 connector C, 26 is load spring C, 27 is rotating motor C, 281 is runner C, 282 is rocker C, 283 is reciprocating rod C, 284 is a sleeve C, 285 is a connecting plate C, 29 is a connector D, 30 is a load spring D, 311 is a runner D, 312 is a rocker D, 313 is a reciprocating rod D, 314 is a sleeve D, 315 is The connecting plate D, 32 is a rotating electrical machine D.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Example 1

A rolling bearing fatigue life test system loaded with radial alternating loads on a crank connecting rod, as shown in Figures 1-2, is used to measure the fatigue life of rolling bearings under radial alternating loads. The rolling bearings are composed of outer rings, The inner ring and a plurality of rolling elements distributed between the inner ring and the outer ring through the cage,

The system includes,

working platform 15,

Drive motor 2 is connected on the work platform 15,

The rotating shaft 10 is connected to the driving motor 2, preferably through a coupling 3, and the rotating shaft 10 is provided with a torque meter 4.

Two fixing fixtures—fixing fixture A5 and fixing fixture B9 are connected to the working platform 15. The fixing fixture A5 holds the test rolling bearing A14, and the fixing fixture B9 holds the test rolling bearing B11 and the test rolling bearing A14. The rolling bearing B 11 and the accompanying test play the role of supporting the rotating shaft 10 .

The movable fixture 8 is located between the fixed fixture A5 and the fixed fixture B9, and is not in contact with the two. It is composed of an upper movable sub-fixture A81 and a lower movable sub-fixture B82. The tested rolling bearings, in this embodiment, hold two tested rolling bearings, namely the tested rolling bearing A13 and the tested rolling bearing B12, each of the tested rolling bearings and the accompanying test rolling bearings are arranged coaxially, and are both sleeved on the rotating shaft 10,

The temperature sensor 16 is arranged in the movable fixture 8 and is in contact with each tested rolling bearing,

The crank connecting rod radial alternating load loading unit 7 is composed of four loading components acting on the movable fixture, and each loading component is composed of a rotating motor connected in sequence, a crank connecting rod transmission mechanism, a load loading spring and a connector. The connector is connected with the movable fixture, and the load springs of the four loading components are set in the shape of a "cross", and the expansion and contraction direction of each load spring is in the radial direction of the rotation axis, and the crank connecting rod The transmission mechanism is composed of a rotating wheel, a rocker and a reciprocating rod that are sequentially connected by transmission. The reciprocating rod is passed through the sleeve fixed on the working platform 15, and is slidably connected with the sleeve in the direction of the load-loaded spring expansion and contraction. The free end of the reciprocating rod is connected to the load-loading spring through the connecting plate, and the running wheel is connected to the rotating motor in transmission.

In this embodiment, as shown in Figure 2, the movable fixture is composed of an upper movable sub-fixture and a lower movable sub-fixture up and down, the bottom of the upper movable sub-fixture is provided with an upper arc groove, and the lower movable sub-fixture The top of the sub-fixture is provided with a lower arc groove, and the upper arc groove and the lower arc groove cooperate to form a clamping part that matches the rolling bearing. The temperature sensor 16 is set in the upper arc groove or the lower arc groove, and is connected outer ring contact. The crank connecting rod radial alternating load loading unit 7 is composed of an upper loading assembly, a lower loading assembly, a left loading assembly and a right loading assembly.

The upper loading assembly is arranged on the top of the upper movable sub-fixture 81 and acts on the top of the upper movable sub-fixture 81. It is composed of a rotating motor A17, a crank-link transmission mechanism A, a load loading spring A19 and a connector A20 connected in sequence, and the crank The connecting rod transmission mechanism A is composed of the runner A181, the rocker A182 and the reciprocating rod A183 which are sequentially connected in transmission. A19 is slidingly connected in the telescopic direction, the free end of the reciprocating rod A183 is connected with the load loading spring A19 through the connecting plate A185, and the runner A181 is connected with the rotary motor A17 through transmission. The left loading assembly is arranged on the left side of the movable fixture 8 and acts on the junction of the upper movable sub-fixture 81 and the lower movable sub-fixture 82, and the rotating motor B21, crank-link transmission mechanism B, load loading spring B23 and Connector B24, crank-link transmission mechanism B is composed of runner B221, rocker B222 and reciprocating rod B223 connected in sequence, reciprocating rod B223 is installed in sleeve B224 fixed on working platform 15, and The barrel B224 is slidably connected in the telescopic direction of the load loading spring B23, the free end of the reciprocating rod B223 is connected to the load loading spring B23 through the connecting plate B225, and the runner B221 is transmission connected to the rotating motor B21. The right loading assembly is arranged on the right side of the movable clamp 8 and acts on the junction of the upper movable sub-fixture 81 and the lower movable sub-fixture 82, and is connected by a rotary motor C27, a crank-link transmission mechanism C, a load loading spring C26 and Connector C25, the crank-link transmission mechanism C is composed of the runner C281, the rocker C282 and the reciprocating rod C283 which are sequentially connected by transmission. The barrel C284 is slidably connected in the telescoping direction of the load loading spring C26, the free end of the reciprocating rod C283 is connected to the load loading spring C26 through the connecting plate C285, and the runner C281 is drivingly connected to the rotating motor C27. The lower loading assembly is arranged under the upper movable sub-fixture 81 and acts on the bottom of the lower movable sub-fixture 81. It is composed of a rotary motor A32, a crank-link transmission mechanism A, a load loading spring A30 and a connector A29 connected in sequence, and the crank The connecting rod transmission mechanism A is composed of a runner A311, a rocker A312 and a reciprocating rod A313 which are sequentially connected by transmission. The reciprocating rod A313 is passed through the sleeve A314 fixed on the working platform 15, and is loaded with the sleeve A314 in a load-loaded spring. The A30 is slidingly connected in the telescopic direction, the free end of the reciprocating rod A313 is connected with the load loading spring A30 through the connecting plate A315, and the runner A311 is connected with the rotating motor A32 through transmission. In this embodiment, each runner is a gear-type runner, and the output shafts of the rotary motor A, the rotary motor B, the rotary motor C and the rotary motor D are respectively provided with worms A and worms matched with the corresponding runners. B, worm C and worm D, each runner is connected to the rotating motor through a corresponding worm. In this implementation, each runner is provided with a plurality of eccentric rocker connection positions along the radial direction, and the rocker is hingedly connected with the reciprocating rod head to tail sequentially, and the free end of the rocker is hingedly connected with the rocker connection position one by one.

The system also includes a controller, the controller is respectively connected with the drive motor, temperature sensor, torque meter and rotating motor in communication, the temperature sensor 16 and the torque meter 4 can collect signals during the running of the rolling bearing, and monitor the running condition of the rolling bearing. The controller can for computer 1. The system also includes an oil supply mechanism for providing lubricating oil for the accompanying rolling bearing and the tested rolling bearing. The oil supply mechanism communicates with the controller, and the oil supply mechanism 6 communicates with the controller to realize oil supply to the rolling bearings. .

The computer controls the rotation of the drive motor to drive the rolling bearing to run at a given speed. In the radial alternating load loading unit of the crank connecting rod, the rotation of the rotating motor is controlled by a computer, and the rotating motion of the rotating motor is converted into a linear motion through the crank connecting rod transmission mechanism, which can affect the tension/compression of the spring. Due to the change of the tension/compression of the spring, the spring will be able to exert a force of different magnitudes and variable directions on the surface of the movable fixture. The bearing alternating load can be realized by adding multiple crank connecting rod radial alternating load loading units in different regions of the movable fixture. The computer controls the oil supply during the operation of the rolling bearing through the oil supply mechanism, and the torque meter and temperature sensor can be used to detect the performance of the rolling bearing during operation.

The above descriptions of the embodiments are for those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments, and apply the general principles described here to other embodiments without creative efforts. Therefore, the present invention is not limited to the above-mentioned embodiments. Improvements and modifications made by those skilled in the art according to the disclosure of the present invention without departing from the scope of the present invention should fall within the protection scope of the present invention.

Claims (9)

1. A rolling bearing fatigue life testing system loaded with radial alternating loads on crank connecting rods, used to measure the fatigue life of rolling bearings under radial alternating loads, the rolling bearings are composed of outer rings, inner rings and cages Composed of a plurality of rolling elements distributed between the inner ring and the outer ring, it is characterized in that the system includes, working platform, drive motor, connected to the working platform, The rotating shaft is connected with the drive motor, and the rotating shaft is provided with a torque meter, Two fixed fixtures are connected on the working platform, and each fixed fixture clamps a rolling bearing to accompany the test. The movable fixture is located between the two fixed fixtures and consists of two opposite movable sub-fixtures. The movable fixture At least one rolling bearing to be tested is held inside, and the rolling bearing to be tested and the rolling bearing to be tested are arranged coaxially and are both sleeved on the rotating shaft. The temperature sensor is set in the movable fixture and is in contact with the tested rolling bearing, The crank connecting rod radial alternating load loading unit is composed of four loading components acting on the movable fixture. Each loading component is composed of a rotating motor connected in sequence, a crank connecting rod transmission mechanism, a load loading spring and a connector. The above-mentioned connector is connected with the movable fixture, and the load-loading springs of the four loading components are arranged in the shape of a "ten", and the expansion and contraction direction of each load-loading spring is in the radial direction of the rotating shaft, and the crank-connecting rod transmission The mechanism is composed of a rotating wheel, a rocker and a reciprocating rod that are sequentially connected by transmission. The reciprocating rod is passed through a sleeve fixed on the working platform, and is slidably connected with the sleeve in the direction of expansion and contraction of the load-loaded spring. The free end of the reciprocating rod is connected with the load-loading spring through the connecting plate, and the running wheel is connected with the rotating motor in transmission. 2. The rolling bearing fatigue life test system according to claim 1, wherein the crank connecting rod is loaded with radial alternating load, wherein the runner is a gear-type runner, and the output shaft of the rotating electrical machine is connected to There is a worm matched with the gear of the running wheel, and the running wheel is connected with the rotating motor through the worm. 3. The rolling bearing fatigue life test system according to claim 1, wherein the crank connecting rod is loaded with radial alternating load, wherein the runner is provided with a plurality of eccentric rocker connection positions along the radial direction, The rocker is hingedly connected with the reciprocating rod head to tail sequentially, and the free end of the rocker is hingedly connected with the connecting position of the rocker alternatively. 4 . The rolling bearing fatigue life testing system with radial alternating load applied to the crank connecting rod according to claim 1 , wherein two rolling bearings to be tested are clamped in the movable fixture. 5. The rolling bearing fatigue life test system according to claim 1, wherein the crank connecting rod is loaded with radial alternating load, wherein the movable fixture is composed of an upper movable sub-fixture and a lower movable sub-fixture which are opposed up and down, The bottom of the upper movable sub-fixture is provided with an upper arc-shaped groove, and the top of the lower movable sub-fixture is provided with a lower arc-shaped groove. part, the crank connecting rod radial alternating load loading unit is composed of an upper loading assembly, a lower loading assembly, a left loading assembly and a right loading assembly, and the upper loading assembly is arranged above the upper movable sub-clamp and acts on The top of the upper movable sub-fixture, the lower loading assembly is arranged under the lower movable sub-fixture and acts on the bottom of the lower movable sub-fixture, and the left loading assembly is arranged on the left side of the movable fixture and acts on the upper movable sub-fixture and the joint of the lower movable clamp, the right loading assembly is arranged on the right side of the movable clamp and acts on the joint of the upper movable clamp and the lower movable clamp. 6. The rolling bearing fatigue life test system according to claim 1, wherein the crank connecting rod is loaded with radial alternating load, wherein the temperature sensor is arranged in the upper arc groove or the lower arc groove, and is connected with the rolling bearing outer ring contact. 7 . The rolling bearing fatigue life testing system with radial alternating load applied to the crank connecting rod according to claim 1 , wherein the rotating shaft is connected to the driving motor through a coupling. 7 . 8. The rolling bearing fatigue life testing system with crank connecting rod loaded with radial alternating load according to claim 1, characterized in that, the system also includes a control system connected in communication with the drive motor, temperature sensor, torque meter and rotating motor respectively device. 9. The rolling bearing fatigue life testing system with crank connecting rod loaded with radial alternating load according to claim 8, characterized in that the system also includes an oil supply mechanism for providing lubricating oil for the accompanying rolling bearing and the rolling bearing being tested , the oil supply mechanism communicates with the controller.