A sliding bearing testing machine

Abstract

The present invention provides a sliding bearing testing machine, which belongs to the field of bearing testing. The sliding bearing testing machine includes a core shaft, a loading structure, and a rotational matching structure. The loading structure includes a loading accessory and a loading power device. The loading accessory includes a force-bearing portion and a connecting portion. The force-bearing portion is located radially outside the core shaft and has a space between the core shaft and the core shaft for accommodating the rotational matching structure. The connecting portion is fixedly connected between the force-bearing portion and the core shaft, and a force transmission structure is provided on the force-bearing portion. The present invention utilizes a loading power device to load the sliding bearing, and the loading force is evenly transmitted to the sliding bearing through the loading accessory, thereby preventing the end of the sliding bearing from tilting and improving the test accuracy.

Description

Technical Field

[0001] The invention belongs to the field of bearing testing, and in particular relates to a sliding bearing testing machine. Background Art

[0002] Currently, in the gearboxes of wind turbines, the bearings between the planetary gears and the pin shafts at their center are gradually being replaced by sliding bearings instead of rolling bearings. Sliding bearings have smaller radial dimensions than rolling bearings, which helps to reduce the overall volume and weight of the gearbox and reduce the manufacturing cost of the gearbox.

[0003] The sliding bearings used in the planetary gears of wind turbine gearboxes require testing during the development and production process to verify that their performance meets the required specifications. Sliding bearings used in wind turbine gearboxes are subject to eccentric wear, so if the test results are to accurately reflect the actual operating conditions of the sliding bearings, the actual operating conditions of the sliding bearings must be replicated during the testing process.

[0004] The general structure of a wind turbine gearbox is described in the planetary transmission mechanism and gearbox disclosed in Chinese invention patent application publication number CN119289047A. The gearbox includes a ring gear, a sun gear, planetary gears, and a planet carrier. The planetary gears are located between the ring gear and the sun gear and mesh with both. A pin is fixed to the planet carrier and passes through the center of the corresponding planetary gear. A sliding bearing is interference-fitted onto the pin, and the planetary gears and the sliding bearing have a clearance fit. Driven by the planet carrier, the pin revolves around the sun gear without rotating itself. During its revolution, the pin drives the planetary gears to revolve. Because the planetary gears mesh with the ring gear, they also rotate during their revolution, i.e., rotate relative to the sliding bearing. As the pin drives the planetary gears to revolve, it applies a force tangential to their orbital trajectory. Consequently, a portion of the sliding bearing is constantly in contact with the planetary gear, generating relative sliding friction. This portion is defined as its working area, while the portion of the sliding bearing that does not contact the planetary gear is the non-working area.

[0005] The working area of ​​the sliding bearings used in planetary gears in wind turbine gearboxes remains in the same location, which is the main cause of eccentric wear in sliding bearings. Currently, the working methods of most bearing testing machines cannot reflect the eccentric wear phenomenon of sliding bearings. The main reason is that, for ease of operation, current bearing testing machines generally use the pins that mount the sliding bearings to actively rotate, while the components that rotate relative to the pins are fixed. As a result, under radial load, the contact point between the sliding bearing and the components that rotate relative to it constantly changes. In other words, its working area will continuously move along the circumference, and the sliding bearing will be subjected to relatively uniform friction along the circumference, which is inconsistent with its actual working conditions.

[0006] A Chinese invention patent application with publication number CN118961203A discloses a sliding bearing testing machine capable of simulating actual working conditions. The sliding bearing testing machine comprises a base, a driving gear, a driven gear, a speed regulating assembly, and a radial load simulation mechanism disposed on the base. The driving gear and the driven gear are meshed, and the speed regulating assembly is used to input rotational power to the driving gear to rotate the driving gear, which in turn drives the driven gear to rotate. A pin is inserted through the center of the driven gear, and the sliding bearing to be tested is interference-fitted onto the pin, with a clearance fit between the sliding bearing and the driven gear. The radial load simulation mechanism comprises two vertically arranged oil cylinders, one at each axial end of the pin, with piston rods facing upward and connected to hinges. The hinges on the two oil cylinders are respectively connected to the axial ends of the pin. In this sliding bearing testing machine, the pin does not rotate, while the driven bearing rotates, thereby simulating the state of uneven wear of the sliding bearing. During the test, the two oil cylinders synchronously pull the ends of the pin downward, applying a radial load to the pin, simulating the actual load conditions of the sliding bearing.

[0007] During the testing process of the above-mentioned sliding bearing testing machine, it is necessary to ensure that the two cylinders have a high degree of synchronization. Otherwise, when the forces applied by the two cylinders deviate greatly, the sliding bearing will have different axial heights at both ends, causing the axial edge to be subjected to concentrated force and severe wear, seriously affecting the detection accuracy.

[0008] Generally, the synchronization accuracy of the cylinder is around 5%. When the loading force is large, the loading force deviation of the two cylinders will be more obvious, making the above phenomenon more likely to occur. However, trying to improve the synchronization accuracy of the cylinder will lead to a sharp increase in costs. Moreover, the synchronization accuracy cannot be further improved after being controlled to a certain level, resulting in deviations in the test that are difficult to eliminate, affecting the technical development of sliding bearings. Summary of the Invention

[0009] The purpose of the present invention is to provide a sliding bearing testing machine to solve the technical problem in the prior art that two oil cylinders are used to provide radial loads to sliding bearings, which results in deviations and poor accuracy of test results.

[0010] To achieve the above-mentioned purpose, the technical solution of the sliding bearing testing machine provided by the present invention is:

[0011] A sliding bearing testing machine includes a core shaft for installing a sliding bearing, a loading structure for radially loading the core shaft, and a rotational cooperation structure that can be sleeved on the outside of the core shaft and rotationally cooperate with the outer peripheral surface of the sliding bearing. The loading structure includes a loading accessory and a loading power device. The loading accessory includes a force-bearing part and a connecting part. The force-bearing part is located radially outside the core shaft and a space is left between the core shaft and the core shaft for accommodating the rotational cooperation structure. The connecting part is fixedly connected between the force-bearing part and the core shaft. The force-bearing part is provided with a force transmission structure for cooperating with the output end of the loading power device and bearing the radial thrust or radial pulling force applied by the loading power device. The line of action of the loading force on the force-bearing part passes through the central area of ​​the sliding bearing installation section on the core shaft.

[0012] As a further improvement, the force transmission structure is used to bear the thrust of the loading power device. A ball head is provided on one of the output end of the loading power device and the force transmission structure, and a ball socket that is embedded and matched with the ball head is provided on the other.

[0013] As a further improvement, the loading power device is located directly above the loading attachment, and the force transmission structure is used to withstand the vertical downward thrust of the loading power device.

[0014] As a further improvement, the sliding bearing testing machine also includes a rotating shaft, one axial end of the rotating shaft is provided with a transmission structure for rotating power input, and the other end is provided with a matching sleeve, the matching sleeve constitutes a rotating matching structure, one axial end of the force-bearing part is connected to the corresponding end of the core shaft through a connecting part, and the other end is in a suspended state.

[0015] As a further improvement, an oil supply channel is provided on the core shaft for providing lubricating oil to the sliding bearing and the rotating mating structure, a gap for oil drainage is left between the axial end face of the mating sleeve and the loading accessory, and at least one radially extending oil drain hole connecting the inner and outer sides of the mating sleeve is provided at the connection between the mating sleeve and the rotating shaft.

[0016] As a further improvement, the force-bearing part is a ring-shaped structure, which covers the oil drain hole. The radial clearance and axial clearance between the matching sleeve and the loading accessory and the oil drain hole are all connected, and the radial clearance constitutes a confluence channel for collecting and guiding the discharge of lubricating oil.

[0017] As a further improvement, an oil storage chamber for storing lubricating oil is provided at the center of the core shaft, and the oil storage chamber is connected to the outer surfaces of the axial ends of the sliding bearing mounting section on the core shaft. The loading accessory or the loading accessory and the core shaft are provided with an oil drain channel for discharging the lubricating oil in the oil storage chamber, and the outlet of the oil drain channel is connected to the confluence channel.

[0018] As a further improvement, a center hole is provided axially through the center of the core shaft, and the center hole constitutes the oil storage chamber. The connecting portion closes one axial end of the center hole of the core shaft, and a radially extending oil hole connecting the outside of the core shaft and the oil storage chamber is provided on the core shaft between the sliding bearing mounting section and the section for fixing the connecting portion. A gap is left between the axial end face of the core shaft and the axial end face of the rotating shaft for lubricating oil to flow into the mounting chamber, and the inlet of the oil drain channel is located on an end face of the connecting portion facing the center hole of the core shaft and is connected to the center hole of the core shaft.

[0019] As a further improvement, the sliding bearing testing machine also includes a guide member for axially guiding the loading accessory during the assembly process, a guide structure that cooperates with the guide member is provided on the force-bearing part, and a limit member is detachably installed on the guide member for limiting one axial end of the assembly consisting of the loading accessory and the core shaft after the assembly is axially assembled.

[0020] As a further improvement, the force-bearing portion is a ring-shaped structure with a horizontal axis, the guiding structure is located on the lower surface of the force-bearing portion, and the force transmission structure is located on the upper surface of the force-bearing portion.

[0021] The present invention provides a beneficial effect: the sliding bearing testing machine is an improvement over the prior art. This sliding bearing testing machine changes the method of radially loading the sliding bearing. A loading attachment and a core shaft form a structure for transmitting a loading force provided by a loading power device to the sliding bearing. This structure directs the line of action of the loading force through the center of the sliding bearing mounting section on the core shaft. This allows the radial load on the sliding bearing to be evenly distributed along its axial direction, preventing one end of the sliding bearing from tilting and affecting test accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the overall structure of the sliding bearing testing machine of Example 1 of the present invention;

[0023] Figure 2 Schematic diagram of the partial structure of Example 1 of the sliding bearing testing machine of the present invention;

[0024] Figure 3 Schematic diagram of the matching structure of the core shaft, sliding bearing and loading accessories in Example 1 of the sliding bearing testing machine of the present invention;

[0025] Figure 4 Schematic diagram of the structure of the rotating shaft in Example 1 of the sliding bearing testing machine of the present invention;

[0026] Figure 5 Schematic diagram of the structure of the loading power device in Example 1 of the sliding bearing testing machine of the present invention;

[0027] Figure 61 is a side view of the guide member in Example 1 of the sliding bearing testing machine of the present invention;

[0028] Figure 7 A top view of the guide member in Example 1 of the sliding bearing testing machine of the present invention;

[0029] Figure 8 Schematic diagram of the partial structure of the sliding bearing testing machine of Example 4 of the present invention;

[0030] Figure 9 Schematic diagram of the partial structure of Example 6 of the sliding bearing testing machine of the present invention;

[0031] Description of reference numerals:

[0032] 1. Upper seat; 2. Lower seat; 3. Core shaft; 31. Installation section; 32. Connection section; 33. Center hole; 4. Rotating shaft; 41. Main shaft; 42. Matching sleeve; 5. Support bearing; 6. Sealing piece; 7. Sliding bearing; 8. Loading accessories; 81. Loading sleeve; 82. Connecting piece; 83. Pressure cover; 84. Ball socket; 9. Loading power device; 91. Loading cylinder; 92. Loading lever; 93. Ball head; 10. Guide piece; 101. Guide groove; 102. Installation hole; 11. Stop plate; 12. Limiting piece; 13. Oil supply channel; 14. Oil injection channel; 15. Oil drain hole; 16. Converging channel; 17. Oil through hole; 18. Oil drain channel; 19. Wear-resistant part; 20. Bushing; 21. Driven gear; 22. Install bearing. DETAILED DESCRIPTION

[0033] The present invention is described in further detail below with reference to the examples.

[0034] In order to solve the problems in the prior art, the basic concept of the present invention is to use a loading power device to load the sliding bearing to improve the accuracy of the test results.

[0035] Specific embodiment 1 of the sliding bearing testing machine provided by the present invention:

[0036] See attached Figure 1 and attached Figure 2 The sliding bearing testing machine includes a mounting seat, a core shaft 3, a loading structure and a rotating shaft 4.

[0037] The mounting base includes an upper base body 1 and a lower base body 2, and the upper base body 1 and the lower base body 2 are fixedly connected to each other. Figure 4The rotating shaft 4 includes a main shaft body 41, a transmission structure and a mating sleeve 42, which are respectively provided at both ends of the main shaft body 41 and are integrally formed with the main shaft body 41. Two sets of support bearings 5 ​​are provided between the main shaft body 41 and the mounting seat to enable the main shaft body 41 to rotate on the mounting seat. The transmission structure is used for transmission connection with a rotary power source. The rotary power source can input a rotational driving force to the main shaft body 41 through the transmission structure, thereby rotating the main shaft body 41. When the main shaft body 41 rotates, it also drives the mating sleeve 42 to rotate with it.

[0038] The outer diameter of the mating sleeve 42 is larger than that of the main shaft body 41, allowing for a larger interior space. A blind hole is axially defined on the end surface of the main shaft body 41 where the mating sleeve 42 connects. This blind hole serves to reduce the overall weight of the rotating shaft 4. To prevent lubricating oil from entering the blind hole during use, the blind hole is machined and then sealed with a plug 6.

[0039] Combined with attachment Figure 3 The core shaft 3 is used to install the sliding bearing 7 to be tested. The sliding bearing 7 has an interference fit with the core shaft 3. The part of the core shaft 3 used to install the sliding bearing 7 is the sliding bearing 7 installation section 31. During the testing of the sliding bearing 7, the core shaft 3 needs to be inserted into the matching sleeve 42, and the sliding bearing 7 is completely inserted into the matching sleeve 42. A gap is left between the sliding bearing 7 and the matching sleeve 42. During the test, the core shaft 3 and the sliding bearing 7 are fixed and the matching sleeve 42 rotates relative to the sliding bearing 7. The matching sleeve 42 can constitute a rotating matching structure that slides with the outer surface of the sliding bearing 7.

[0040] The installation section 31 of the sliding bearing 7 is close to the end of the core shaft 3 installed in the matching sleeve 42, and the end of the core shaft 3 located outside the matching sleeve 42 serves as the connecting section 32 for connecting with the loading structure.

[0041] The loading structure includes a loading attachment 8 and a loading power unit 9. The loading attachment 8 is fixedly connected to the core shaft 3, while the loading power unit 9 is mounted on the upper base 1. The loading attachment 8 includes a force-bearing portion and a connecting portion. The force-bearing portion is a horizontally axial annular structure that fits over the outside of the core shaft 3. An annular space for accommodating the mating sleeve 42 is left between the force-bearing portion and the core shaft 3. After assembly, a gap is left between the inner side of the force-bearing portion and the outer side of the mating sleeve 42. The connecting portion connects between one axial end of the force-bearing portion and the connecting section 32 of the core shaft 3, sealing the corresponding ends of the force-bearing portion and the core shaft 3.

[0042] The loading attachment 8 can be processed as a whole, but in this embodiment, for the convenience of manufacturing, see the attached Figure 3The loading accessory 8 is divided into a loading sleeve 81, a connector 82 and a pressure cap 83, wherein the main part of the loading sleeve 81 constitutes the above-mentioned force-bearing part, and the connector 82 and the pressure cap 83 constitute the above-mentioned connecting part. Specifically, the connector 82 is a cap-shaped structure, the connecting section 32 of the core shaft 3 is inserted into the connector 82 and the two are fixedly connected by axial bolts, the connector 82 is inserted at one axial end of the loading sleeve 81, the end of the loading sleeve 81 for connecting to the connector 82 is provided with an inverted edge, and the mouth of the connector 82 is provided with an outverted edge for limiting the inverted edge on the axial inside, the pressure cap 83 is fixedly installed at the end of the connector 82 axially away from the core shaft 3 by bolts, the diameter of the pressure cap 83 is larger than the diameter of the connector 82, and the edge of the pressure cap 83 can limit the axial outside of the loading sleeve 81.

[0043] In this embodiment, the loading sleeve 81 and the connecting piece 82 are nested inside and outside, and the connecting piece 82 and the core shaft 3 are also nested inside and outside, which can better transmit the radial force between the three. Compared with simply connecting with bolts, the force transmission is more stable and reliable, and can ensure that higher test accuracy can be obtained under larger loads.

[0044] See attached Figure 5 The loading power device 9 includes a loading cylinder 91 and a loading lever 92. The loading cylinder 91 is fixedly mounted on the upper base 1 with its piston rod facing downward. The upper end of the loading lever 92 is fixed to the piston rod of the loading cylinder 91, and the lower end acts on the loading sleeve 81. The lower end of the loading lever 92 serves as the output end of the loading power device 9. The upper side of the loading sleeve 81 is provided with a force transmission structure for cooperating with the output end of the loading power device 9. The force transmission structure is specifically a ball socket 84. The lower end of the loading lever 92 is provided with a ball head 93 that is embedded and matched with the ball socket 84. Both the ball socket 84 and the ball head 93 are hemispherical structures.

[0045] The piston rod of the loading cylinder 91 extends, causing the loading lever 92 to move downward, thereby applying a vertical downward thrust to the loading sleeve 81. This thrust is also directed toward the axis of the loading sleeve 81. Because of the downward thrust, the weight of the loading attachment 8 and the core shaft 3 also acts downward. As a result, the combined force acting on the loading attachment 8, the core shaft 3, and the sliding bearing 7 is downward, causing the lower side of the sliding bearing 7 to contact the inner side of the mating sleeve 42. The portion of the sliding bearing 7 that contacts the mating sleeve 42 is its working area, while the remaining portion is the non-working area.

[0046] The fit of the socket 84 and the ball head 93 allows the thrust force to be precisely directed to a single point at the bottom of the socket 84, improving loading accuracy. If there is a slight misalignment in the installation of the loading power unit 9, the fit of the socket 84 and the ball head 93 automatically corrects the misalignment, ensuring that the force application point remains at the bottom of the socket 84.

[0047] By setting the ball socket 84 on the loading sleeve 81 , the loading sleeve 81 can be conveniently formed by machining. In other implementations of this embodiment, the ball socket 84 can also be set at the lower end of the loading rod 92 and the ball head 93 can be set on the loading sleeve 81 .

[0048] In this embodiment, the position of the ball socket 84 corresponds to the axial center area of ​​the installation section 31 of the sliding bearing 7 in the axial direction. In this way, the line of action of the loading force on the loading sleeve 81 will pass through the axial center area of ​​the installation section 31 of the sliding bearing 7, thereby ensuring that the force on the working area of ​​the sliding bearing 7 is uniform, and avoiding the phenomenon that the core shaft 3 rises after the force is deflected, so that only the axial end of the sliding bearing 7 contacts the matching sleeve 42.

[0049] Before testing, the sliding bearing 7 must be assembled onto the core shaft 3, then the core shaft 3 must be connected to the loading attachment 8, and finally the assembly consisting of the sliding bearing 7, core shaft 3, and loading attachment 8 must be moved axially to assemble with the rotating shaft 4. A guide 10 is fixedly mounted on the lower base 2. The guide 10 is used to axially guide the assembly during the axial movement of the loading attachment 8, core shaft 3, and sliding bearing 7. The loading sleeve 81 is provided with a guide structure that cooperates with the guide 10.

[0050] Specifically, see the attached Figure 6 and attached Figure 7 A rectangular guide groove 101 is provided on the guide member 10, and the guide structure on the loading sleeve 81 is a rectangular strip protrusion adapted to the guide groove 101. The cooperation between the guide structure and the guide groove 101 can not only enable the guide member 10 to guide the loading sleeve 81, but also position the loading sleeve 81 in the circumferential direction to prevent the loading accessory 8 from rotating.

[0051] The guide member 10 has a mounting hole 102 at the bottom of the guide groove 101. A countersunk bolt threadedly connected to the lower base 2 is provided in the mounting hole 102, thereby securing the guide member 10 to the lower base 2. Stop plates 11 are bolted to both end surfaces of the guide member 10 in the direction of guiding the loading attachment 8. The stop plates 11 are located on both sides of the base on the lower base 2 for mounting the guide member 10 and engage with the base to prevent the guide member 10 from moving.

[0052] A limit member 12 is detachably provided in the guide groove 101 by means of bolts. The limit member 12 is located at one end of the loading accessory 8 away from the rotating shaft 4 and limits the end to prevent the loading accessory 8 from axial movement.

[0053] Lubricating oil is used to reduce friction and wear between the sliding bearing 7 and the mating sleeve 42, and the lubricating oil is always in a flowing state, using dynamic pressure to maintain a certain distance between the sliding bearing 7 and the mating sleeve 42. The flowing lubricating oil can also take away the friction heat and friction debris generated by the relative rotation of the sliding bearing 7 and the mating sleeve 42.

[0054] The core shaft 3 is provided with an oil supply passage 13 for supplying lubricating oil between the sliding bearing 7 and the mating sleeve 42. This oil supply passage 13 comprises an annular groove and multiple branches spaced axially along the circumference of the core shaft 3. One end of each branch communicates with the oil outlet hole in the sliding bearing 7 via a radial channel, while the other end of each branch communicates with the annular groove via a radial channel. The annular groove is provided in the connecting section 32 of the core shaft 3. Because the connecting section 32 is inserted into the connector 82, the sidewalls of the annular groove and the inner surface of the connector 82 together form a channel for the circumferential flow of lubricating oil.

[0055] The loading attachment 8 is provided with an oil injection channel 14 for injecting lubricating oil into the annular groove. The oil injection channel 14 is distributed on both the connecting piece 82 and the loading sleeve 81, and the inlet of the oil injection channel 14, that is, the oil injection port, is provided on the axial end face of the loading sleeve 81. The axial end face of the loading sleeve 81 is a plane, so it can facilitate the oil injection operation.

[0056] The oil outlet hole on the sliding bearing 7 is located in the middle thereof. After the lubricating oil enters between the sliding bearing 7 and the matching sleeve 42 , it flows toward the axial ends of the sliding bearing 7 under the action of pressure and is finally discharged.

[0057] A gap is also left between the end of the mating sleeve 42 that extends into the loading attachment 8 and the loading attachment 8, so lubricating oil flowing out of this end can flow out through the gap between the mating sleeve 42 and the loading attachment 8. The connection between the mating sleeve 42 and the rotating shaft 4 is provided with a plurality of circumferentially spaced, radially extending, and communicating with the inside and outside of the mating sleeve 42. Lubricating oil at this end is discharged through the oil drain holes 15.

[0058] The end of the loading sleeve 81 away from the connecting piece 82 protrudes axially from the corresponding end of the core shaft 3, and after assembly, this end of the loading sleeve 81 covers the oil drain hole 15. In this way, on the one hand, the lubricating oil flowing out of the gap between the axial end face of the mating sleeve 42 and the loading accessory 8 and the lubricating oil flowing out of the oil drain hole 15 can all flow into the gap between the outer peripheral surface of the mating sleeve 42 and the inner peripheral surface of the loading sleeve 81, and finally flow out uniformly from one end of the opening of the loading accessory 8, which is convenient for collecting the used lubricating oil. The gap between the outer peripheral surface of the mating sleeve 42 and the inner peripheral surface of the loading sleeve 81 constitutes a confluence channel 16; on the other hand, the center of gravity of the loading accessory 8, the core shaft 3 and the sliding bearing 7 as a whole can be adjusted so that the center of gravity approaches the axial center area of ​​the mounting section 31 of the sliding bearing 7.

[0059] However, relying solely on the above structure to discharge lubricating oil cannot meet normal usage requirements. In this embodiment, a center hole 33 is axially provided at the center position of the core shaft 3, and a connector 82 closes one end of the center hole 33. The core shaft 3 is provided with a plurality of oil holes 17 extending radially and spaced apart in the circumferential direction. A gap is left between the end of the sliding bearing 7 close to the loading attachment 8 and the loading attachment 8. The oil holes 17 correspond to the gap and can guide the lubricating oil in the gap into the center hole 33. A gap is left between the end face of the core shaft 3 inserted into the matching sleeve 42 and the end face of the main shaft body 41 of the rotating shaft 4. The gap can guide the lubricating oil therein into the center hole 33 of the core shaft 3.

[0060] The center hole 33 of the core shaft 3 can serve as an oil storage chamber for temporarily storing lubricating oil. The lubricating oil entering the oil storage chamber is discharged through the oil drain channel 18. The oil drain channel 18 is provided on the connector 82. Its inlet is located on the end surface of the connector 82 facing the center hole 33 of the core shaft 3 and is connected to the center hole 33 of the core shaft 3. Its outlet is connected to the confluence channel 16. The oil drain channel 18 is formed on the connector 82 by machining. Due to the tortuous structure of the oil drain channel 18, a through hole for forming the oil drain channel 18 is first machined on the connector 82 during machining. Then, one end of the through hole is sealed to form the final oil drain channel 18.

[0061] In this way, the lubricating oil at both ends of the sliding bearing 7 can not only flow radially outward, but also flow radially inward, which actually increases the flow channel of the lubricating oil and thus ensures smooth flow of the lubricating oil. Of course, in other embodiments, only the channel for allowing the lubricating oil to flow radially outward or only the channel for allowing the lubricating oil to flow radially inward can be provided as needed.

[0062] A wear-resistant part 19 is fixedly installed on the axial end face of the connecting part 82 near the mating sleeve 42 by bolts. The wear-resistant part 19 can be made of a softer copper material. The wear-resistant part 19 can withstand the axial force from the mating sleeve 42. During the process of the lubricating oil being retained at this location, the wear-resistant part 19 can be lubricated by the way, but the wear-resistant part 19 generally does not rub against the mating sleeve 42, so it is not lubricated separately.

[0063] The method of testing the sliding bearing 7 using the sliding bearing testing machine is as follows:

[0064] First, the sliding bearing 7 to be tested is installed on the core shaft 3. At this time, the core shaft 3 and the loading attachment 8 are both in a loose and unassembled state. The sliding bearing 7 is heated to expand it and then it is put on the core shaft 3. After the sliding bearing 7 is put on the core shaft 3, the positioning pins are passed through the oil outlet holes on the sliding bearing 7 and the corresponding holes on the core shaft 3 to position the sliding bearing 7 in the circumferential direction and axial direction. Finally, after the sliding bearing 7 cools down and forms an interference fit with the core shaft 3, the positioning pins are removed.

[0065] Then the core shaft 3 , the connecting piece 82 , the loading sleeve 81 and the pressure cover 83 are assembled together. During the assembly process, the sensor for testing parameters such as temperature is also installed in the loading accessory 8 .

[0066] The assembly consisting of the sliding bearing 7, core shaft 3, and loading attachment 8 is then assembled with the rotating shaft 4. The specific assembly process involves first installing the guide member on the lower base 2, then placing the assembly onto the guide member and pushing it axially. When the assembly is ready to mate with the rotating shaft 4, it is slightly lifted upward. Once the assembly is aligned with the holes of the mating sleeve 42 on the rotating shaft 4, further axial pushing is performed to complete the assembly. After assembly, a gap remains between the lower end surface of the loading sleeve 81 and the bottom surface of the guide groove 101 to facilitate loading.

[0067] Other preparatory steps for testing are then performed, such as connecting the oil supply line, connecting the rotational power source, and inserting the ball head 93 on the loading lever 92 into the ball socket 84 on the loading sleeve 81. After completing these preparatory steps, the shaft 4 can be rotated, and the loading sleeve 81 can be gradually loaded using the loading power device 9. Loading is stopped after the set value is reached, and the test of the sliding bearing 7 can begin.

[0068] Specific embodiment 2 of the sliding bearing testing machine provided by the present invention:

[0069] This embodiment is based on Example 1, and differs from Example 1 in that, in this embodiment, the lower end of the loading lever is hinged to the loading sleeve through a pin, so that the pin can also play a role in gathering the loading force, but the pin needs to be manually assembled during the assembly process.

[0070] Specific embodiment 3 of the sliding bearing testing machine provided by the present invention:

[0071] This embodiment is based on Example 1, differing from Example 1 in that the lower end of the loading lever is hingedly connected to the loading sleeve via a pin. During loading, the loading cylinder pulls the loading lever upward, thereby applying an upward force to the loading sleeve. In the loading mode of this embodiment, the upper side of the sliding bearing contacts the mating sleeve, resulting in the working area of ​​the sliding bearing being located on its upper side.

[0072] In other implementations of this embodiment, the loading power device may also be disposed below or on a horizontal side of the loading accessory to apply pulling forces in other directions to the loading accessory.

[0073] Specific embodiment 4 of the sliding bearing testing machine provided by the present invention:

[0074] This embodiment is based on embodiment 1, and differs from embodiment 1 in that the force-bearing portion in this embodiment is not a ring-shaped structure, but a cantilever structure.

[0075] For the specific structure, please refer to the attached Figure 8 In this embodiment, the loading accessory 8 is an integrated structure. The connecting part of the loading accessory 8 is fixedly connected to the end of the core shaft 3 by bolts, the force-bearing part is cantilevered above the core shaft 3, and the force transmission structure is arranged on the upper surface of the receiving part.

[0076] Specific embodiment 5 of the sliding bearing testing machine provided by the present invention:

[0077] This embodiment is based on embodiment 1, and differs from embodiment 1 in that the mating sleeve in this embodiment is not driven to rotate by the rotating shaft, and the rotating shaft is only used to enable the mating sleeve to rotate relative to the mounting seat.

[0078] In this embodiment, a driven gear is fixedly mounted on the outside of the mating sleeve. A driving gear, which meshes with the driven gear, is rotatably mounted on the mounting base. The driving gear is connected to the rotary power source, and the mating sleeve is driven by a gear transmission. To achieve this, the loading sleeve in this embodiment has a larger diameter to accommodate the driven gear. A window is provided on one horizontal side of the loading sleeve for the driving gear to pass through. The central axis of the driving gear is located outside the loading sleeve, and one side of the driving gear passes through the window to mesh with the driven gear.

[0079] Specific embodiment 6 of the sliding bearing testing machine provided by the present invention:

[0080] This embodiment is based on embodiment 1, and the difference from embodiment 1 is that, see attached Figure 9 The rotational matching structure in this embodiment is a shaft sleeve 20, on the outside of which a driven gear 21 is fixedly mounted, and a driving gear rotatably mounted on the mounting seat that meshes with the driven gear 21 and is located on the horizontal side of the driven gear 21. The driving gear is transmission-connected to the rotating power source, thereby utilizing gear transmission to drive the shaft sleeve 20 to rotate.

[0081] Mounting bearings 22 for mounting and supporting the sleeve 20 are provided on the outer sides of both ends of the sleeve 20. The mounting bearings 22 are installed between the upper seat body 1 and the lower seat body 2. The installation form of the sleeve 20 is similar to that in the invention patent with application publication number CN118961203A, and will not be repeated here.

[0082] The core shaft 3 is inserted into the sleeve 20 , and the sliding bearing 7 used for testing is installed in the middle of the core shaft 3 . The sliding bearing 7 is completely located in the sleeve 20 , and both axial ends of the core shaft 3 extend out of the sleeve 20 .

[0083] The loading attachment 8 in this embodiment is a U-shaped member. The U-shaped member includes a horizontally extending force-bearing portion located in the middle, and vertically extending connecting portions located at both ends of the force-bearing portion. The upper ends of the two connecting portions are fixedly connected to the axial ends of the core shaft 3. The U-shaped member can be divided into several detachable parts according to installation requirements, which will not be described in detail. The lower base 2 is provided with an escape hole for the force-bearing portion of the U-shaped member to avoid the force-bearing portion, so that the force-bearing portion can move up and down.

[0084] The load-bearing portion is located below the core shaft 3. The force transmission structure is located at the center of the lower side of the load-bearing portion, specifically a hinge seat and a hinge pin mounted on the hinge seat. The loading power device 9 is located below the load-bearing portion and is hinged to the load-bearing portion via the hinge pin. The loading power device 9 pulls the load-bearing portion downward, applying a downward pulling force to the load-bearing portion. Moreover, because the force transmission structure is centrally located, the resulting force applied to the sliding bearing 7 is relatively evenly distributed.

[0085] The oil supply and drain channels in the core shaft 3 in this embodiment can refer to the oil supply and drain channels in the invention patent with application publication number CN118961203A, and will not be described in detail.

[0086] Specific embodiment 7 of the sliding bearing testing machine provided by the present invention:

[0087] This embodiment is based on embodiment 1, and differs from embodiment 1 in that the force-bearing portion in this embodiment does not cover the oil drain hole, so no confluence channel is formed. In this embodiment, a larger collection box is provided below the core shaft to collect lubricating oil.

[0088] Specific embodiment 8 of the sliding bearing testing machine provided by the present invention:

[0089] This embodiment is based on Example 1, and differs from Example 1 in that the center hole on the core shaft in this embodiment does not penetrate the core shaft, the opening of the center hole is located on the end of the core shaft inserted into the mating sleeve, and the end of the core shaft inserted into the connector is a closed structure.

[0090] Specific embodiment 9 of the sliding bearing testing machine provided by the present invention:

[0091] This embodiment is based on embodiment 1, and differs from embodiment 1 in that the opening of the oil drain channel in this embodiment is provided on the core shaft, and the oil drain channel first passes through the core shaft and then passes through the loading accessory.

[0092] Specific embodiment 10 of the sliding bearing testing machine provided by the present invention:

[0093] This embodiment is based on the embodiment 1, and differs from the embodiment 1 in that no guide is provided in this embodiment, and the assembly consisting of the loading attachment, the core shaft and the sliding bearing is assembled by hoisting.

[0094] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments without inventive effort, or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A sliding bearing testing machine, comprising a core shaft for mounting a sliding bearing, a loading structure for radially loading the core shaft, and a rotational engagement structure capable of being sleeved on the outside of the core shaft and rotationally engaged with the outer peripheral surface of the sliding bearing, characterized in that: The loading structure includes a loading accessory and a loading power device. The loading accessory includes a force-bearing part and a connecting part. The force-bearing part is located radially outside the core shaft and a space is left between the core shaft and the core shaft for accommodating a rotational matching structure. The connecting part is fixedly connected between the force-bearing part and the core shaft. The force-bearing part is provided with a force transmission structure for cooperating with the output end of the loading power device and bearing the radial thrust or radial pulling force applied by the loading power device. The line of action of the loading force on the force-bearing part passes through the central area of ​​the sliding bearing installation section on the core shaft; the sliding bearing testing machine also includes a rotating shaft, one axial end of the rotating shaft is provided with a transmission structure for rotating power input, and the other end is provided with a matching sleeve, the matching sleeve constitutes a rotational matching structure, one axial end of the force-bearing part is connected to the corresponding end of the core shaft through the connecting part, and the other end is in a suspended state.

2. The sliding bearing testing machine according to claim 1, wherein: The force transmission structure is used to bear the thrust of the loading power device. A ball head is provided on one of the output end of the loading power device and the force transmission structure, and a ball socket embedded with the ball head is provided on the other.

3. The sliding bearing testing machine according to claim 2, wherein: The loading power device is located directly above the loading attachment, and the force transmission structure is used to withstand the vertical downward thrust of the loading power device.

4. The sliding bearing testing machine according to any one of claims 1 to 3, characterized in that: An oil supply channel is provided on the core shaft for providing lubricating oil to the sliding bearing and the rotating mating structure. A gap for oil drainage is left between the axial end face of the mating sleeve and the loading accessory. At least one radially extending oil drain hole connecting the inner and outer sides of the mating sleeve is provided at the connection between the mating sleeve and the rotating shaft.

5. The sliding bearing testing machine according to claim 4, characterized in that: The force-bearing part is a ring-shaped structure, which covers the oil drain hole. The radial gap between the matching sleeve and the loading accessory is connected with the axial gap and the oil drain hole, and the radial gap constitutes a confluence channel for collecting and guiding the discharge of lubricating oil.

6. The sliding bearing testing machine according to claim 5, characterized in that: An oil storage chamber for storing lubricating oil is provided at the center of the core shaft, and the oil storage chamber is communicated with the outer surfaces of the axial ends of the sliding bearing mounting section on the core shaft. An oil drain channel for discharging the lubricating oil in the oil storage chamber is provided on the loading accessory or the loading accessory and the core shaft, and the outlet of the oil drain channel is communicated with the confluence channel.

7. The sliding bearing testing machine according to claim 6, wherein: A center hole is provided axially through the center of the core shaft, and the center hole constitutes the oil storage chamber. The connecting portion closes one axial end of the center hole of the core shaft. An oil hole extending radially and connecting the outside of the core shaft and the oil storage chamber is provided on the core shaft between the sliding bearing mounting section and the section for fixing the connecting portion. A gap is left between the axial end face of the core shaft and the axial end face of the rotating shaft for lubricating oil to flow into the mounting chamber. The inlet of the oil drain channel is located on one end face of the connecting portion facing the center hole of the core shaft and is connected to the center hole of the core shaft.

8. The sliding bearing testing machine according to any one of claims 1 to 3, characterized in that: The sliding bearing testing machine also includes a guide member for axially guiding the loading accessory during the assembly process. A guide structure that cooperates with the guide member is provided on the force-bearing part. A limit member is detachably installed on the guide member for limiting one axial end of the assembly consisting of the loading accessory and the core shaft after the assembly is axially assembled.

9. The sliding bearing testing machine according to claim 8, characterized in that: The force-bearing part is a ring-shaped structure with a horizontal axis, the guiding structure is located on the lower surface of the force-bearing part, and the force transmission structure is located on the upper surface of the force-bearing part.

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