Anti-unbalance loading testing machine for aero-engine main shaft bearing test

Abstract

The invention discloses an anti-unbalance loading testing machine for aero-engine main shaft bearing test, which comprises a machine body, a core shaft and two test seats arranged in the machine body, the two test seats are coaxially and oppositely arranged, and test holes for the core shaft to penetrate through are formed in the two test seats in a penetrating manner; a test cavity for mounting an external to-be-tested bearing is formed between the inner peripheral wall of the test hole and the outer peripheral wall of the mandrel, and one of the test seats is provided with an axial loading structure for applying an axial load to the other test seat; a guide structure is arranged between the two test seats, the guide structure is used for being in linkage fit with the axial loading structure to correctly conduct the axial load so as to prevent unbalance loading, and the two test seats are both provided with radial loading structures used for applying radial loads to the corresponding test seats. The problem that a traditional aero-engine main shaft bearing test device is prone to unbalance loading when the bearing is subjected to axial loading and radial loading is solved.

Description

Technical Field

[0001] The invention relates to the technical field of bearing test fixtures, in particular to an anti-eccentric load testing machine for testing a main shaft bearing of an aero-engine. Background Art

[0002] As the core power unit of various aircraft, the performance of aircraft engines is directly related to the overall performance and flight safety of aircraft. As a key component of the engine, the main shaft bearing of aircraft engines is of vital importance. Once a failure occurs, it is very likely to cause the engine to stop running, and then cause a serious aviation accident. For this reason, various performance tests after its production are particularly critical. Aircraft engine bearings work under extremely complex and harsh working conditions. Large loads, high temperatures, ultra-high speeds and large diameters (high dn values) are their notable characteristics.

[0003] The load is mainly axial force, which comes from the strong thrust generated by the aircraft engine acting on the bearing; the radial force is formed by the centrifugal force generated by the high-speed rotation of the engine blades and various vibration conditions. In the traditional test structure, the axial loading and radial loading cylinders are fixed to the test bearing through the ball head. However, when the test shaft system is deformed, dry friction will occur between the ball head and the loading accessories. When the dry friction is greater than the load value generated by the bearing deformation, the bearing will generate additional internal force, resulting in a deviation between the actual loading force and the load force detected by the test. At the same time, the contact point of the ball head will also generate additional force; after radial loading, the bearing and the test mandrel will deform in the direction of the loading force, making it difficult to accurately load the axial force to the center of the bearing, thereby forming an eccentric load. Due to the unreasonable test structure, the test bearing is often damaged and cannot truly and accurately reflect the performance of the bearing, which has a serious impact on the performance evaluation of the aircraft engine. Especially when the bearing is subjected to axial load, the traditional aircraft engine main shaft bearing test device is very prone to axial load eccentricity, which greatly hinders the accurate testing and research of the performance of the aircraft engine main shaft bearing. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides an anti-eccentric load testing machine for testing aircraft engine main shaft bearings, in order to solve the problem that conventional aircraft engine main shaft bearing testing devices are prone to eccentric load when the bearings are subjected to axial and radial loads.

[0005] In order to achieve the above-mentioned purpose, the present invention provides an anti-eccentric load testing machine for testing aircraft engine main shaft bearings, comprising a machine body, a core shaft and two test seats arranged in the machine body, the two test seats are coaxial and relatively arranged, and both of the test seats are penetrated by a test hole for the core shaft to pass through, and a test cavity for installing an external bearing to be tested is formed between the inner circumferential wall of the test hole and the outer circumferential wall of the core shaft, one of the test seats is provided with an axial loading structure for applying an axial load to the other test seat, a guide structure for cooperating with the axial loading structure to correctly transmit the axial load to prevent eccentric load is provided between the two test seats, and both of the test seats are provided with a radial loading structure for applying a radial load to the corresponding test seat.

[0006] The advantages of adopting the above technical solution are: installing the external bearing to be tested in the test cavity formed between the inner peripheral wall of the test hole of the two test seats and the outer peripheral wall of the core shaft, and fixing the bearing through a connecting device (such as a collar or mounting ring in the prior art, connecting the inner peripheral wall of the collar and the outer ring of the bearing through connecting bolts, and connecting the outer peripheral wall of the collar and the inner peripheral wall of the test hole through connecting bolts). At this time, the core shaft passes through two coaxial and relatively arranged test seats, and the axial loading structure arranged on one of the test seats is started. The axial loading structure starts to work and applies an axial load to the other test seat. In this process, the axial force generated by the axial loading structure does not act directly on the test seat, but is connected to the test seat through the guide structure. The structure is coordinated and coordinated, so that the axial load can be correctly transmitted along the predetermined path. The guide structure is like a precise track, guiding the axial force to accurately act on the test bearing, ensuring that the bearing will not be biased when bearing the axial load. At the same time or after the axial loading, the radial loading structures on the two test seats are started respectively to apply radial loads to the corresponding test seats. The radial loading structure accurately controls the magnitude and direction of the applied radial force according to the test requirements, so that the test bearing can bear a reasonable radial load on the basis of bearing the axial load, simulating the stress of the bearing when the aircraft engine is actually running. During the entire test process, the axial loading structure, the guide structure and the radial loading structure work together. The guide structure continuously monitors and adjusts the transmission direction of the axial load to ensure that it is always accurate; the radial loading structure adjusts the radial load size in real time according to the test requirements, and acts on the test bearing together with the axial load; the test seat and the mandrel stably support the test bearing to ensure the stability of the test environment. Through the close cooperation of various structures, the performance test of the main shaft bearing of the aircraft engine under the action of axial and radial loads is completed, and the test data is accurately obtained, providing a reliable basis for evaluating the bearing performance.

[0007] The above technology uses a uniquely designed axial loading structure and a guide structure to ensure that when an axial load is applied to the test bearing, the load is accurately transmitted to the center of the bearing, avoiding the phenomenon that the axial force in the traditional test device cannot be loaded to the center of the bearing and forms an eccentric load, which greatly improves the accuracy of the test. Since the axial loading structure and the outer ring of the bearing are together, the deformation caused by the radial loading force will cause the loading device and the test bearing to move together, thereby reducing the introduction of eccentric loads; the radial loading structure can accurately apply radial loads to the corresponding test seat, and in the entire loading process, the synergistic effect of the guide structure and the axial loading structure makes The test bearings can remain stable when subjected to axial and radial loads, effectively reducing the damage to the test bearings caused by off-center loads, thereby improving the reliability of the test and more realistically reflecting the performance of the aircraft engine main shaft bearings; since additional damage to the test bearings caused by off-center loads is effectively avoided, not only the test costs are reduced, but also the wear and tear on the test equipment is reduced, the overall service life of the test equipment is extended, and the equipment utilization efficiency is improved; accurate bearing test results can provide a reliable basis for the design optimization and performance improvement of aircraft engines, help to develop aircraft engines with better performance, safer and more stable operation, and promote technological progress in the aviation field.

[0008] The present invention is further configured as follows: loading blocks are provided on both sides of the two test seats, and axial loading cylinders are provided on the two loading blocks on one of the test seats, and the axial loading cylinder is an axial loading structure, and the guide structure includes two guide rods, and the starting ends of the two guide rods are coaxially connected to the output ends of the two axial loading cylinders, and the ends of the two guide rods are respectively connected to the two loading blocks of the other test seat.

[0009] The advantages of adopting the above technical solution are as follows: the axial loading cylinder is arranged on the loading block of one test seat, and through the coaxial connection with the guide rod, it is ensured that the axial load can be accurately transmitted to the loading block of another test seat along the straight line direction determined by the guide rod. Through this structural design, the axial force is greatly avoided from being offset during the transmission process, and the problem that the axial force is difficult to be accurately loaded to the center of the bearing in the traditional test device is effectively solved, so that the test bearing can remain stable when bearing the axial load, which significantly improves the accuracy of the test and lays a solid foundation for obtaining reliable bearing performance data; t is the guide rod as the core component of the guide structure, the starting end of which is coaxially connected to the output end of the axial loading cylinder, and the end is connected to the loading block of another test seat, so as to construct a stable and accurate axial load transmission path. During the entire test process, the guide rod can continuously guide and constrain the force output by the axial loading cylinder, effectively reducing the test error caused by the force transmission deviation. At the same time, this stable load transmission path helps to maintain the dynamic balance of the test system, so that the test bearing can still work normally under complex load environments, and improves the reliability of the test results; the layout of the axial loading cylinder and the guide rod makes the test operation more convenient. During the test, the operator can easily adjust the axial load applied to the test bearing by controlling the output force of the axial loading cylinder. At the same time, due to the guiding effect of the guide rod, the load adjustment process is smoother and more accurate, without the need for complex calibration operations; at the same time, since the axial force is transmitted through two high-rigidity guide rods, the fulcrum of the guide structure is much larger than the fulcrum of the outer ring of the test bearing. When an offset load occurs, the offset load first acts on the guide structure. Since the offset load is not large, it will not affect the performance of the guide structure, thereby preventing the offset load from swinging, thereby preventing the offset load from being transmitted to the test bearing and causing damage to the test bearing; the above technology uses two sets of loading mechanisms to reduce the range of the sensor and improve the control accuracy. The loading cylinder uses synchronous control to reduce the error. When the two loading cylinders deviate, the load sensor will feedback the difference control system to adjust the pressure of the two cylinders so that the output load of the two cylinders is consistent. During the adjustment process, the guide mechanism plays a protective role to prevent the occurrence of offset loads.

[0010] The present invention further provides that: the guide structure also includes a linear bearing arranged on the loading block, and each of the linear bearings is connected and cooperated with a respective adjacent guide rod.

[0011] The advantages of adopting the above technical solution are as follows: in the above technology, a linear bearing is arranged on the loading block, and it is connected and matched with the adjacent guide rod, which greatly improves the guiding accuracy of the guiding structure. The linear bearing can provide high-precision linear constraints for the movement of the guide rod, further reducing the slight deviation that may occur in the guide rod during the transmission of the axial load, ensuring that the axial force is always transmitted to the test seat along a precise path, thereby more accurately applying the axial load to the test bearing, further improving the accuracy and reliability of the test results, and making the test data more truly reflect the performance of the main shaft bearing of the aircraft engine under actual working conditions. The use of linear bearings and guide rods can significantly reduce the friction resistance between the two. Compared with the traditional direct contact method, the rolling element structure inside the linear bearing greatly reduces the friction coefficient of the guide rod during movement, which not only helps the axial loading cylinder to output the axial load more smoothly and reduce energy loss, but also effectively avoids the wear and heating of the guide rod caused by excessive friction, prolongs the service life of the guide rod and the entire test device, and also makes the load transmission during the test more stable and efficient.

[0012] The present invention further provides: a load sensor is provided at the end of the guide rod, the load sensor is installed on an adjacent loading block and a detection shaft is provided at the detection end of the load sensor, the detection shaft is coaxially connected to the guide rod and the detection shaft and the guide rod are connected by a pin.

[0013] The above technical solution is beneficial in that: a load sensor is set at the end of the guide rod, and the detection shaft is connected to the guide rod through a coaxial connection, which can measure the actual value of the axial load in the transmission process in real time and accurately. The load sensor can convert the detected force signal into an electrical signal to provide accurate load data for the test personnel, which helps to gain a deep understanding of the axial load size borne by the test bearing under different working conditions, and provides rich and accurate data support for the comprehensive evaluation of bearing performance, so that R&D personnel can optimize the bearing design and improve performance based on reliable data. The detection shaft and the guide rod are connected by pins and remain coaxial, ensuring the stability and consistency of load transmission. The pin connection method can effectively prevent relative displacement or loosening between the detection shaft and the guide rod, and ensure that the load sensor can accurately measure the axial force transmitted by the guide rod. This is crucial to maintaining the high precision of load measurement during the test, avoiding measurement errors caused by unstable connections, further improving the credibility and repeatability of the test results, and providing a solid guarantee for the accurate performance test of the main shaft bearing of an aircraft engine.

[0014] The present invention further provides that: a plurality of the loading blocks are each provided with a heat-insulating and shock-absorbing plate.

[0015] The advantages of adopting the above technical solution are: in the above technology, the heat-insulating and shock-absorbing plate is set on the loading block, which can effectively resist the high temperature attack from the simulated working conditions of the aircraft engine. Since the high temperature generated by the aircraft engine during operation will be transmitted through the test seat and the loading block, the heat-insulating and shock-absorbing plate can greatly reduce the rate of heat transfer to the axial loading cylinder, the guide rod and other key components. This not only helps to maintain the normal operating temperature of these components and prevent problems such as material performance degradation and structural deformation caused by overheating, but also ensures the output accuracy of the axial loading cylinder and the guiding stability of the guide rod, thereby ensuring the accuracy and reliability of the entire test process.

[0016] The present invention further provides that: the radial loading structure includes a radial loading cylinder arranged on the machine body, the output end of the radial loading cylinder is connected and matched with the corresponding test seat top wall, and the output end of the radial loading cylinder is arranged vertically relative to the core shaft.

[0017] The above technical solution is beneficial in that: the radial loading cylinder is arranged on the body, and its output end is connected to the top wall of the corresponding test seat and is relatively perpendicular to the core shaft. This design can accurately control the radial load applied to the test seat. The vertically arranged output end can ensure that the radial force acts on the test seat accurately and then is transmitted to the test bearing, avoiding the test error caused by the loading angle deviation. The test personnel can accurately simulate the different radial load conditions that the main shaft bearing of the aircraft engine bears in actual operation by adjusting the output force of the radial loading cylinder, which provides a reliable means for in-depth research on the performance of the bearing under complex radial force conditions. Through the radial loading structure, the test machine can more realistically simulate the actual working environment of the main shaft bearing of the aircraft engine. When the aircraft engine is running, the bearing is not only subjected to axial force, but also to the centrifugal force generated by the high-speed rotation of the fan blades and the radial force caused by various vibrations. The radial loading structure in this patent can accurately apply radial loads, work in conjunction with the axial loading structure, and fully and accurately reproduce the complex stress state of the bearing in the engine, so that the test results are closer to the performance of the bearing in actual use, and provide more valuable reference data for the optimization design and quality evaluation of the bearing.

[0018] The present invention is further provided with: a connecting seat is provided on the top wall of the test seat, a swing block is provided on the output end of the radial loading cylinder, a swing groove is provided on the swing block along the length direction of the core shaft, a connecting plate is swingably provided in the swing groove, the connecting plate is connected to the connecting seat and the connecting plate and the connecting seat are relatively vertically arranged, and a connecting pin is movably connected between the connecting plate and the swing groove.

[0019] The above technical solution is beneficial in that: in the above technology, a connecting seat is set on the top wall of the test seat, and the output end of the radial loading cylinder is connected to the connecting seat through a swing block, a swing groove and a connecting plate. This unique structure greatly improves the flexibility of radial load application. The swing groove on the swing block cooperates with the movable connection between the connecting plate and the connecting pin, allowing the output end of the radial loading cylinder to swing flexibly within a certain range. During the test, when the test seat is slightly displaced due to various factors (such as shaft deformation, vibration, etc.), the structure can automatically adapt and continue to accurately apply the radial load to the test seat, ensuring the stability and accuracy of the radial force on the test bearing, avoiding load deviation caused by the displacement of the test seat, thereby improving the reliability of the test data; at the same time, the swing fulcrum of the radial loading cylinder is originally away from the axis. When the main shaft bearing of the aircraft engine is tested, it is affected by the high temperature environment and the stress generated during the loading process. The test shaft system will inevitably undergo thermal deformation and loading deformation, which will cause the two test bearings to move along the axis. At this time, since the swing fulcrum of the radial loading cylinder is far away from the axis, when the bearing is displaced, the radial loading cylinder can sensitively follow the swing. From the perspective of error control, the farther the swing fulcrum is from the axis, the smaller the error value caused by the swing of the radial loading cylinder when the bearing has the same displacement, and the error value can be strictly controlled within the control accuracy value of the equipment, which greatly improves the accuracy of radial loading and ensures that the stress condition of the test bearing when bearing radial load is closer to the actual working condition, providing a strong guarantee for obtaining high-precision test data. When displacement deformation occurs during the test, since the radial swing fulcrum is far away from the axis, the force generated by a very small deformation can drive the radial loading cylinder to swing. This sensitive response mechanism enables the radial loading cylinder to quickly adapt to the deformation of the test shaft system and continuously provide a stable and accurate radial load for the test bearing. Compared with traditional test devices, this design can better cope with complex and changeable test conditions, effectively avoid the problem of inaccurate radial load application caused by shaft system deformation, further improve the reliability and repeatability of the test, and make the test results more truly reflect the performance of the main shaft bearing of the aircraft engine in actual operation.

[0020] The present invention further provides that: a servo motor for driving the core shaft to rotate axially is arranged on the machine body.

[0021] The advantages of adopting the above technical solution are: the servo motor installed on the machine body is used to drive the mandrel to rotate axially, which can highly simulate the actual working state of the main shaft of the aircraft engine. When the aircraft engine is running, the main shaft is in continuous axial operation, driving the bearing to work synchronously. This test machine realizes the axial operation of the mandrel through the servo motor, so that the test bearing undergoes dynamic working conditions similar to those in actual use while bearing axial and radial loads, thereby more comprehensively and realistically testing the performance of the bearing in a complex operating environment, and providing more practical test data for evaluating the reliability of the bearing in the aircraft engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a front cross-sectional view of the present invention; Figure 2 It is a side sectional view of the present invention; Figure 3 A three-dimensional view of the test seat and its linkage structure in the present invention; Figure 4 It is a three-dimensional view of the matching state of the test seat and the axial loading structure in the present invention. DETAILED DESCRIPTION

[0023] The present invention provides an anti-eccentric load test machine for testing the main shaft bearing of an aircraft engine, comprising a machine body 1, a core shaft 11 and two test seats 2 arranged in the machine body 1, the two test seats 2 are coaxial and arranged opposite to each other, the two test seats 2 are penetrated by a test hole 21 for the core shaft 11 to pass through, and a test cavity 22 for installing a bearing to be tested from the outside is formed between the inner peripheral wall of the test hole 21 and the outer peripheral wall of the core shaft 11, one of the test seats 2 is provided with an axial loading structure for applying an axial load to the other test seat 2, and a device for cooperating with the axial loading structure to correctly transmit the axial load to prevent the eccentric load from being applied to the main shaft bearing of an aircraft engine. The guide structure of the anti-biased load, the two test seats 2 are provided with radial loading structures for applying radial loads to the corresponding test seats 2, the two test seats 2 are provided with loading blocks 23 on both sides, the two loading blocks 23 on one of the test seats 2 are provided with axial loading cylinders 3, the axial loading cylinders 3 are the axial loading structure, the guide structure includes two guide rods 31, the starting ends of the two guide rods 31 are respectively coaxially connected to the output ends of the two axial loading cylinders 3, the ends of the two guide rods 31 are respectively connected to the two loading blocks 23 of the other test seat 2, the guide structure also includes a setting on the loading block 2 3, each of the linear bearings 32 is connected and matched with the respective adjacent guide rods 31, a load sensor 33 is arranged at the end of the guide rod 31, the load sensor 33 is installed on the adjacent loading block 23, and a detection shaft 331 is arranged at the detection end of the load sensor 33, the detection shaft 331 is coaxially connected with the guide rod 31, and the detection shaft 331 is connected with the guide rod 31 through a pin 332, and a plurality of the loading blocks 23 are provided with a heat insulation and shock absorbing plate 231, and the radial loading structure includes a radial loading cylinder 4 arranged on the machine body 1, and the output end of the radial loading cylinder 4 is connected to the corresponding test The top wall of the test seat 2 is connected and matched, and the output end of the radial loading cylinder 4 is arranged perpendicularly to the core shaft 11. The top wall of the test seat 2 is provided with a connecting seat 24, and the output end of the radial loading cylinder 4 is provided with a swing block 41. The swing block 41 is provided with a swing groove 42 along the length direction of the core shaft 11, and a connecting plate 241 is swingably arranged in the swing groove 42. The connecting plate 241 is connected to the connecting seat 24 and the connecting plate 241 and the connecting seat 24 are arranged perpendicularly to each other. A connecting pin 43 is movably connected between the connecting plate 241 and the swing groove 42, and a servo motor 12 for driving the core shaft 11 to make axial movement is provided on the machine body 1.

[0024] The bearing to be tested in the above technology is marked as 5 in the attached drawing of the specification.

[0025] The basic principles and main features of the present invention and the advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which shall fall within the scope of the present invention to be protected. The scope of protection of the present invention shall be defined by the attached claims and their equivalents.

Claims

1. An anti-eccentric load testing machine for testing the main shaft bearing of an aircraft engine, characterized in that: It includes a machine body, a core shaft and two test seats arranged in the machine body, the two test seats are coaxial and arranged opposite to each other, and the two test seats are penetrated by a test hole for the core shaft to pass through, and a test cavity for installing an external bearing to be tested is formed between the inner circumferential wall of the test hole and the outer circumferential wall of the core shaft, one of the test seats is provided with an axial loading structure for applying an axial load to the other test seat, and a guide structure is provided between the two test seats for cooperating with the axial loading structure to correctly transmit the axial load to prevent unbalanced loading, and the two test seats are provided with a radial loading structure for applying a radial load to the corresponding test seat.

2. The anti-eccentric load testing machine for testing the main shaft bearing of an aircraft engine according to claim 1, characterized in that: Loading blocks are arranged on both sides of the two test seats, and axial loading cylinders are arranged on the two loading blocks on one of the test seats. The axial loading cylinder is an axial loading structure, and the guide structure includes two guide rods. The starting ends of the two guide rods are coaxially connected to the output ends of the two axial loading cylinders, and the ends of the two guide rods are respectively connected to the two loading blocks of the other test seat.

3. The anti-eccentric load testing machine for testing the main shaft bearing of an aircraft engine according to claim 2, characterized in that: The guide structure also includes a linear bearing arranged on the loading block, and each of the linear bearings is connected and matched with a respective adjacent guide rod.

4. The anti-eccentric load testing machine for testing the main shaft bearing of an aircraft engine according to claim 3, characterized in that: A load sensor is arranged at the end of the guide rod, the load sensor is installed on an adjacent loading block and a detection shaft is arranged at the detection end of the load sensor, the detection shaft is coaxially connected to the guide rod and the detection shaft and the guide rod are connected by a pin.

5. The anti-eccentric load testing machine for testing the main shaft bearing of an aircraft engine according to claim 2, characterized in that: A plurality of the loading blocks are each provided with a heat-insulating and shock-absorbing plate.

6. The anti-eccentric load testing machine for testing the main shaft bearing of an aircraft engine according to claim 1, characterized in that: The radial loading structure comprises a radial loading cylinder arranged on the machine body, wherein the output end of the radial loading cylinder is connected and matched with the top wall of the corresponding test seat, and the output end of the radial loading cylinder is arranged vertically relative to the core shaft.

7. The anti-eccentric load testing machine for testing the main shaft bearing of an aircraft engine according to claim 6, characterized in that: A connecting seat is provided on the top wall of the test seat, and a swing block is provided on the output end of the radial loading cylinder. A swing groove is opened on the swing block along the length direction of the core shaft, and a connecting plate is swingably provided in the swing groove. The connecting plate is connected to the connecting seat and the connecting plate and the connecting seat are relatively vertically arranged, and a connecting pin is movably connected between the connecting plate and the swing groove.

8. The anti-eccentric load testing machine for testing the main shaft bearing of an aircraft engine according to claim 1, characterized in that: The machine body is provided with a servo motor for driving the core shaft to perform axial rotation.

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