Rear bearing lubricating oil passage structure

Abstract

The application discloses a rear bearing lubricating oil path structure, which comprises a rear bearing support, a rear bearing, an internal sliding oil elbow pipe, an external oil pipe and an elbow pipe sealing chuck. The lower oil outlet end of the internal sliding oil elbow pipe is communicated with the rear bearing through a sliding oil flow path arranged in the rear bearing support, and the opposite upper oil inlet end of the internal sliding oil elbow pipe extends upward to an upper outlet arranged at the top end of the rear bearing support. The elbow pipe sealing chuck is arranged in the upper outlet, and the two ends of the elbow pipe sealing chuck are respectively sleeved on the outer circles of the upper oil inlet end of the internal sliding oil elbow pipe and the oil outlet end of the external oil pipe, so that the elbow pipe sealing chuck gradually seals and clamps the internal sliding oil elbow pipe or the oil outlet end of the external oil pipe is gradually sealed and inserted in the elbow pipe sealing chuck in the process of rotating the elbow pipe sealing chuck. The rear bearing lubricating oil path structure has the advantages that the connection and fastening operation between the internal sliding oil elbow pipe and the elbow pipe sealing chuck and between the elbow pipe sealing chuck and the external oil pipe is simple, and the total cost of debugging and trial running can be effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, and in particular, to a rear bearing lubrication circuit structure. Background Technology

[0002] The rear bearing of the rotor in the core engine of an aero-engine is surrounded by high-temperature, high-pressure exhaust gas. It operates at high speeds, with significant vibrations and a harsh environment. Therefore, it requires a continuous supply of low-temperature, clean lubricating oil and the removal of high-temperature, foamy, contaminated lubricating oil. This lubricating oil is then cooled, degassed, filtered, and pressurized by the lubricating oil system before being recycled. The hollow support plate of the rear bearing mount serves as a passageway for the lubricating oil pipelines, connecting the rear bearing housing to the lubricating oil pipe joints on the outer wall of the turbine casing via internal lubricating oil pipes.

[0003] Due to differences in turbine model structure, the internal lubricating oil pipes in most models are actually externally inserted straight pipes. They pass through the outer wall of the turbine casing, insert into the hollow support plate, and then extend into the pipe thread of the rear bearing housing. The lubricating oil pipe connector protrudes from the outer wall of the turbine casing, as shown in the attached diagram. Figure 1 As shown, it is very convenient to connect the external lubricating oil pipe. In a few models, due to the space occupied by the combustion chamber, the internal lubricating oil pipe is internally bent. This internal lubricating oil bend is connected to the rear bearing housing with flange bolts and passes through the hollow support plate.

[0004] Externally inserted straight pipes suffer from poor thread strength and sealing reliability, as well as a large diameter, resulting in high airflow resistance in the hollow support plate. Furthermore, the connection between the externally inserted straight pipe and the threaded joint has a high failure rate for lubricating oil leakage, and the large hole depth makes inspection with a borescope difficult. Internal lubricating oil bends cannot extend beyond the turbine casing wall due to assembly interference; their length is limited, requiring the lubricating oil pipe clamp to be inserted inside the turbine casing to connect with the internal lubricating oil bend. Summary of the Invention

[0005] This invention provides a rear bearing lubrication circuit structure to solve the technical problems of existing external straight pipe lubrication circuit structures, such as frequent oil leakage, difficulty in inspection with a borescope, cumbersome operation for debugging and testing, and high testing costs.

[0006] The technical solution adopted in this invention is as follows:

[0007] A rear bearing lubrication circuit structure includes: a rear bearing support, a rear bearing to be lubricated disposed within the rear bearing support, an internal oil bend for guiding lubricating oil to lubricate the rear bearing, an external oil pipe disposed outside the rear bearing support, and a bend sealing clamp for connecting the internal oil bend and the external oil pipe; the internal oil bend is disposed within the rear bearing support, and its lower oil outlet end is connected to the rear bearing through an oil flow path provided within the rear bearing support, while its corresponding upper oil inlet end extends upward to an upper outlet opened at the top of the rear bearing support; the bend sealing clamp is installed in the upper outlet, and its two ends are respectively fitted onto the outer circumference of the upper oil inlet end of the internal oil bend and the oil outlet end of the external oil pipe, so that during the rotation of the bend sealing clamp, the bend sealing clamp gradually seals and clamps the internal oil bend, or the oil outlet end of the external oil pipe gradually seals and is inserted into the bend sealing clamp.

[0008] Furthermore, the internal lubricating oil bend includes a vertically arranged lower section and an upper section that transitions to the top of the lower section and extends upward at an inclination; the lower section passes downward through the hollow support plate of the rear bearing support and is connected to a flange bolt joint installed in the lubricating oil flow path; the upper outlet is inclined, and the upper section extends upward at an inclination to the upper outlet; the bend sealing clamp is inclinedly installed in the upper outlet, and the lower clamping end clamps the upper section, while the opposite upper connecting end extends out of the rear bearing support and connects to the external oil pipe.

[0009] Furthermore, the bend sealing clamp includes an inner sleeve, an outer sleeve, and a self-locking nut assembly that are fitted together, as well as a sealing sleeve and a locking ring assembly. The sealing sleeve is fitted onto the outer circle of the oil inlet end of the inner lubricating bend and is installed inside the outer sleeve. The lower clamping section of the inner sleeve is inserted into the outer sleeve and is threadedly connected to the outer sleeve, so that during the rotation of the inner sleeve, the lower clamping section of the inner sleeve gradually clamps the sealing sleeve inward, thereby gradually clamping the inner lubricating bend. The locking ring assembly is installed on the outer circles of the inner sleeve and the outer sleeve respectively, so as to lock the inner sleeve and the outer sleeve in place. The oil outlet end of the outer oil pipe is inserted into the upper connecting section of the inner sleeve, and the self-locking nut assembly is installed on the outer oil pipe and is threadedly connected to the outer circle of the upper connecting section of the inner sleeve, so that during the rotation of the self-locking nut assembly, the outer oil pipe is gradually sealed and tightened into the upper connecting section of the inner sleeve.

[0010] Furthermore, the inner sleeve includes a hollow tubular inner sleeve with external threads machined on the outer circumferences at both ends; the outer sleeve includes a hollow tubular outer sleeve with internal threads machined on the inner wall that match the external threads on the outer circumference of the lower clamping section of the inner sleeve; the inner sleeve is screwed into the outer sleeve through the external threads on its lower clamping section, and the port of the lower clamping section is surrounded by a sealing sleeve, so that as the inner sleeve continues to rotate, the port of the lower clamping section gradually clamps the sealing sleeve inward.

[0011] Furthermore, the sealing sleeve is a hollow cylindrical shape, with its inner shaft hole being a through hole of equal diameter, and its outer circular surface gradually narrowing inward from the middle to both ends to form an outer conical surface; the inner wall surface at the lower clamping section port of the inner sleeve is an inner conical surface that adapts to the outer conical surface at one end of the sealing sleeve, and the inner wall surface at the lower clamping section port of the outer sleeve is an inner conical surface that adapts to the outer conical surface at the other end of the sealing sleeve, so that during the rotation of the inner sleeve, the outer conical surfaces at both ends of the sealing sleeve gradually come into contact with the inner conical surfaces of the inner sleeve and the outer sleeve respectively to form a conical surface fit.

[0012] Furthermore, the inner sleeve also includes an inner sleeve flange disposed on the outer circumference of the middle part of the inner sleeve tube, and the outer circumference surface of the inner sleeve flange is provided with inner sleeve protrusions that are evenly distributed and protruding in the circumferential direction; the outer sleeve also includes an outer sleeve flange and a mounting lug disposed sequentially at intervals on the outer circumference of the connecting section of the outer sleeve tube, and the outer circumference surface of the outer sleeve flange is provided with outer sleeve protrusions that are evenly distributed and protruding in the circumferential direction; the locking ring assembly includes a hollow annular locking ring, a connecting lug connected to the outer circumference of the locking ring, and a locking member, the inner circumference surface of the locking ring is provided with a concave toothed ring that is concave and respectively engages with the inner sleeve protrusions and the outer sleeve protrusions, the locking ring is respectively fitted onto the inner sleeve flange and the outer sleeve flange, and the inner sleeve and the outer sleeve are limited by the engagement of the concave toothed ring with the inner sleeve protrusions and the outer sleeve protrusions, and the locking member is simultaneously provided with the mounting lug and the connecting lug to lock and fix the inner sleeve and the outer sleeve.

[0013] Furthermore, the outer sleeve is also machined with a through-hole for oil leakage collection. The oil leakage collection hole is located between the outer sleeve flange and the mounting lug. The oil leakage collection hole is used to collect the lubricating oil leaking between the bent pipe sealing clamp and the internal lubricating bend, and to determine whether the inner sleeve is tightened properly.

[0014] Furthermore, the self-locking sleeve and nut assembly includes a nut and a self-locking sleeve fixed in the inner hole of the nut. One end of the self-locking sleeve is open, and the other end protrudes towards the center to form a limiting convex ring. The inner wall of the self-locking sleeve is provided with an internal thread. The self-locking sleeve is installed on the outer circle of the oil outlet end of the external oil pipe, and the limiting convex ring abuts against the limiting step on the outer circle of the external oil pipe. The internal thread of the self-locking sleeve is connected to the external thread of the connecting section on the inner sleeve. During the rotation of the self-locking sleeve and nut assembly, the limiting convex ring abuts against the limiting step to gradually press the external oil pipe axially into the inner sleeve.

[0015] Furthermore, the sealing sleeve is made of Teflon or copper, and the outer surface of the sealing sleeve is electroplated with a softer metal; the outer circle of the oil inlet end of the internal lubricating bend is ground round and then electroplated with silver.

[0016] Furthermore, the bend sealing clamp also includes a retaining ring, a first sealing ring, and a second sealing ring; the retaining ring is fitted onto the outer circle of the oil outlet end of the outer oil pipe, with one side abutting against the limiting step and the other side abutting against the limiting protrusion; the first sealing ring is fitted onto the outer circle of the oil outlet end of the outer oil pipe and is located between the outer oil pipe and the inner sleeve; the second sealing ring is fitted onto the outer circle of the lower clamping section of the inner sleeve and is clamped between the end of the outer sleeve and the inner sleeve flange.

[0017] The present invention has the following beneficial effects:

[0018] Compared to existing technologies that use sealing rings, fuses, and locking plates for sealing connections, which result in inconvenient debugging, long delivery and commissioning times, and extended maintenance periods, and where each commissioning and testing process involves breaking fuses and locking plates, indirectly increasing the total cost, and where broken sealing rings, fuses, and locking plate lugs generate unremovable debris, the rear bearing lubrication circuit structure of this invention uses a bent pipe sealing clamp whose two ends are respectively fitted onto the outer circumference of the oil inlet end of the internal lubricating bend and the oil outlet end of the external oil pipe. Thus, during the rotation of the bent pipe sealing clamp, not only can the clamp gradually seal and tighten the internal lubricating bend, but the oil outlet end of the external oil pipe can also be gradually sealed and tightened within the clamp. This simplifies the connection and tightening operation between the internal lubricating bend and the clamp, and between the clamp and the external oil pipe. During commissioning and testing, there is no need to cut the sealing ring, unscrew the fuse, or break the locking plate, thus effectively reducing the total cost of commissioning and testing. It also avoids generating unremovable debris, meeting the requirement of one-time installation and testing before delivery. Furthermore, during installation, after the bent pipe sealing clamp is connected to the internal lubricating oil bend, the lubricating oil outlet of the bent pipe sealing clamp is blocked. It is then tested for sealing performance and flow rate along with the turbine casing on a high-pressure sealing test bench. If the test is successful, the bent pipe sealing clamp can be left undisassembled or disassembled as little as possible. This simplifies the sealing performance and flow rate testing operation. The connection between the bent pipe sealing clamp, the internal lubricating oil bend, and the external oil pipe is reliably sealed. Leakage can be checked visually or with a borescope, making leak detection simple. The structure of this invention can be flexibly applied to fuel lines, hydraulic lines, air lines, and sealing cables.

[0019] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0021] Figure 1 This is a schematic diagram of the existing rear bearing lubrication circuit structure;

[0022] Figure 2 This is a schematic diagram of the rear bearing lubrication circuit structure according to a preferred embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the connection space between the internal lubricating oil bend, the bend sealing clamp, and the external oil pipe in a preferred embodiment of the present invention.

[0024] Figure 4 yes Figure 3 A schematic diagram of the cross-sectional structure;

[0025] Figure 5 yes Figure 3 A partial sectional view of the outer and inner layers;

[0026] Figure 6 yes Figure 3 A partial cross-sectional view of the central sealing sleeve;

[0027] Figure 7 yes Figure 3 A partial sectional view of the inner sleeve;

[0028] Figure 8 yes Figure 3 A schematic diagram of the spatial structure of the central locking ring.

[0029] Legend

[0030] 1. Rear bearing support; 101. Lubricating oil flow path; 102. Hollow support plate; 2. Rear bearing; 3. Internal lubricating oil bend; 4. External oil pipe; 5. Bend sealing clamp; 20. Inner sleeve; 21. Inner sleeve tube; 22. Inner sleeve flange; 23. Inner sleeve tooth; 30. Outer sleeve; 301. Oil leakage collection hole; 31. Outer sleeve tube; 32. Outer sleeve flange; 33. Mounting lug; 34. Outer sleeve tooth; 40. Self-locking threaded sleeve and nut assembly; 41. Nut; 42. Self-locking threaded sleeve; 43. Limiting ring; 50. Sealing sleeve; 60. Locking ring assembly; 61. Locking ring; 62. Inner concave toothed ring; 63. Connecting lug; 64. Locking element; 70. Snap ring; 80. First sealing ring; 90. Second sealing ring; 6. Flange bolt joint. Detailed Implementation

[0031] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0032] Reference Figure 2A preferred embodiment of the present invention provides a rear bearing lubrication circuit structure, including: a rear bearing support 1, a rear bearing 2 to be lubricated disposed within the rear bearing support 1, an internal lubricating oil bend 3 for guiding lubricating oil to lubricate the rear bearing 2, an external oil pipe 4 disposed outside the rear bearing support 1, and a bend sealing clamp 5 for connecting the internal lubricating oil bend 3 and the external oil pipe 4. The internal lubricating oil bend 3 is disposed within the rear bearing support 1, and its lower oil outlet end is connected to the rear bearing 2 through a lubricating oil flow path 101 provided within the rear bearing support 1, while its corresponding upper oil inlet end extends upward to an upper outlet opened at the top of the rear bearing support 1. The bend sealing clamp 5 is installed in the upper outlet, and the two ends of the bend sealing clamp 5 are respectively fitted onto the oil inlet end of the inner lubricating bend 3 and the oil outlet end of the outer oil pipe 4, so that during the rotation of the bend sealing clamp 5, the bend sealing clamp 5 gradually seals and clamps the inner lubricating bend 3, or gradually seals and clamps the oil outlet end of the outer oil pipe 4 into the bend sealing clamp 5.

[0033] Compared to existing technologies that use sealing rings, fuses, and locking plates for sealing connections, which result in inconvenient debugging, long delivery and commissioning times, and extended maintenance periods, and where each commissioning and commissioning process involves breaking fuses and locking plates, indirectly increasing the total cost, and where broken sealing rings, fuses, and locking plate lugs also produce unremovable debris, the rear bearing lubrication circuit structure of this invention uses a bent pipe sealing clamp 5, with its two ends respectively fitted onto the outer circumference of the oil inlet end of the internal lubricating bend 3 and the oil outlet end of the external oil pipe 4. Thus, during the rotation of the bent pipe sealing clamp 5, not only can the bent pipe sealing clamp 5 gradually seal and clamp the internal lubricating bend 3, but the oil outlet end of the external oil pipe 4 can also gradually seal and tighten within the bent pipe sealing clamp 5. This simplifies the connection and tightening operation between the internal lubricating bend 3 and the bent pipe sealing clamp 5, and between the bent pipe sealing clamp 5 and the external oil pipe 4. Furthermore, during the trial run and debugging process, there is no need to cut the sealing ring, unscrew the fuse, or break the locking plate, thus effectively reducing the total cost of debugging and trial run, and without generating any unavoidable excess material, meeting the requirement of one-time installation and one-time testing before delivery; In addition, during installation, after the bent pipe sealing clamp 5 is sleeved with the internal lubricating oil bend 3, the lubricating oil outlet of the bent pipe sealing clamp 5 is blocked, and a sealing test and flow test are conducted on the high-pressure sealing test bench together with the turbine casing. After passing the test, the bent pipe sealing clamp 5 can be left undisassembled or disassembled as little as possible, thus simplifying the sealing and flow test operation. The connection between the bent pipe sealing clamp 5, the internal lubricating oil bend 3, and the external oil pipe 4 is reliably sealed, and the connection can be checked for leakage by visual inspection or a borescope. The leakage inspection operation is simple. The structure of this invention can be flexibly applied to fuel lines, hydraulic lines, air lines, and sealing cables.

[0034] Optionally, such as Figure 2As shown, the internal lubricating oil bend 3 includes a vertically arranged lower section and an upper section that transitions to the top of the lower section and extends upward at an incline. The lower section passes downward through the hollow support plate 102 of the rear bearing support 1 and connects to the flange bolt joint 6 located in the lubricating oil flow path 101. The upper outlet is inclined, and the upper section extends upward at an incline into the upper outlet. The bend sealing clamp 5 is inclinedly installed in the upper outlet, with its lower clamping end holding the upper section, and its corresponding upper connecting end extending out of the rear bearing support 1 and connecting to the external oil pipe 4. In this optional embodiment, an inclined upper outlet is machined on the rear bearing support 1 for installing the bend sealing clamp 5. The inclined installation helps reduce the engine height, thus facilitating a more rational arrangement of the lubricating oil pipeline.

[0035] In existing technologies, externally inserted straight pipes are installed during the final assembly stage. Since their threads are located deep within the engine, borescopes cannot directly detect oil leaks, leading to a lower delivery pass rate. Leaks are typically inferred indirectly from high oil consumption and smoke emanating from the support after shutdown. Furthermore, the externally inserted straight pipe suffers from poor sealing reliability after loosening, resulting in a short component lifespan. In this invention, during installation, the curved pipe sealing clamp 5 is connected to the internal oil curved pipe 3, blocking the oil outlet of the curved pipe sealing clamp 5. It is then subjected to sealing and flow tests on a high-pressure sealing test bench along with the turbine casing. This allows for oil leak checks on the internal oil curved pipe 3 during component assembly, avoiding the need for leak detection during test runs and delivery. This significantly simplifies the subsequent test run and delivery process, improving delivery speed. Moreover, the flange bolt joint connection method is resistant to vibration and thermal strain, ensuring high sealing reliability and a long component lifespan.

[0036] Preferably, such as Figure 2 As shown, the diameter of the internal lubricating oil bend 3 of the present invention is smaller than that of the existing external straight pipe, thereby reducing the airflow resistance of the hollow support plate and improving engine performance.

[0037] Optionally, such as Figure 3 and Figure 4As shown, the elbow sealing clamp 5 includes an inner sleeve 20, an outer sleeve 30, and a self-locking threaded nut assembly 40, as well as a sealing sleeve 50 and a locking ring assembly 60. The sealing sleeve 50 is fitted onto the outer circumference of the oil inlet end of the inner oil elbow 3 and is installed inside the outer sleeve 30. The lower clamping section of the inner sleeve 20 is inserted into the outer sleeve 30 and threadedly connected to it, so that during the rotation of the inner sleeve 20, the lower clamping section of the inner sleeve 20 gradually clamps the sealing sleeve 50 inward, thereby gradually clamping the inner oil elbow 3. The locking ring assembly 60 is respectively installed on the outer circumferences of the inner sleeve 20 and the outer sleeve 30 to lock the inner sleeve 20 and the outer sleeve 30 in place. The oil outlet end of the external oil pipe 4 is inserted into the upper connecting section of the inner sleeve 20. The self-locking nut assembly 40 is installed on the external oil pipe 4 and threadedly connected to the outer circular surface of the upper connecting section of the inner sleeve 20, so that the external oil pipe 4 is gradually sealed and tightened into the upper connecting section of the inner sleeve 20 during the rotation of the self-locking nut assembly 40.

[0038] In this optional solution, such as Figure 7 As shown, the inner sleeve 20 includes a hollow tubular inner sleeve 21, with external threads machined on the outer circumferences at both ends of the inner sleeve 21. Figure 5 As shown, the outer sleeve 30 includes a hollow tubular outer sleeve 31, and the inner wall of the outer sleeve 31 is machined with an internal thread that matches the external thread on the outer circle of the lower clamping section of the inner sleeve 21. Figure 4 As shown, the inner sleeve 21 is screwed into the outer sleeve 31 through the external thread on its lower clamping section, and the port of the lower clamping section surrounds the sealing sleeve 50, so that as the inner sleeve 21 continues to rotate, the port of the lower clamping section gradually clamps the sealing sleeve 50 inward. In this optional solution, the connection operation between the inner sleeve 20 and the outer sleeve 30 is simple, and the tightness of the inner sleeve 20 clamping the sealing sleeve 50 can be adjusted by rotating the inner sleeve 20, thereby adjusting the tightness of the sealing sleeve 50 clamping the internal lubricating oil bend 3. The adjustment operation is simple, and the inner sleeve 20 and the outer sleeve 30 are easy to disassemble, assemble, and connect.

[0039] Preferably, such as Figure 4 As shown, the inner hole of the connecting section of the inner sleeve 21 is a concave cone-shaped hole, which is concave at the end face to form a conical fit with the outer conical surface of the oil outlet end of the outer oil pipe 4, thereby effectively preventing oil leakage between the outer oil pipe 4 and the inner sleeve 21.

[0040] In this optional solution, such as Figure 5-7As shown, the sealing sleeve 50 is a hollow cylindrical shape with an inner shaft hole of uniform diameter. Its outer circular surface gradually tapers inward from the middle to both ends, forming an outer conical surface. The inner wall surface at the lower clamping section port of the inner sleeve 21 is an inner conical surface that adapts to the outer conical surface at one end of the sealing sleeve 50, and the inner wall surface at the lower clamping section port of the outer sleeve 31 is an inner conical surface that adapts to the outer conical surface at the other end of the sealing sleeve 50. This allows the outer conical surfaces at both ends of the sealing sleeve 50 to gradually come into contact with the inner conical surfaces of the inner sleeve 21 and the outer sleeve 31, respectively, forming a conical fit during the rotation of the inner sleeve 21. In this optional scheme, the lower clamping section port of the inner sleeve 21 forms a conical seal with one end of the sealing sleeve 50, and the lower clamping section port of the outer sleeve 31 forms a conical seal with the other end of the sealing sleeve 50. Thus, when the inner sleeve 21 is rotated, the two conical seals can be tightened simultaneously, effectively preventing oil leakage between the inner sleeve 20 and the outer sleeve 30.

[0041] In this optional solution, such as Figures 4-8 As shown, the inner sleeve 20 also includes an inner sleeve flange 22 disposed on the outer circumference of the middle part of the inner sleeve tube 21, and the outer circumference surface of the inner sleeve flange 22 is provided with inner sleeve protrusions 23 that are evenly distributed circumferentially and protrude outwards. The outer sleeve 30 also includes an outer sleeve flange 32 and a mounting lug 33 that are sequentially and spaced apart on the outer circumference of the connecting section of the outer sleeve tube 31, and the outer circumference surface of the outer sleeve flange 32 is provided with outer sleeve protrusions 34 that are evenly distributed circumferentially and protrude outwards. The locking ring assembly 60 includes a hollow annular locking ring 61, a connecting lug 63 connected to the outer circle of the locking ring 61, and a locking member 64. The inner circle surface of the locking ring 61 is provided with a concave toothed ring 62 that engages with the inner sleeve tooth 23 and the outer sleeve tooth 34 respectively. The locking ring 61 is respectively fitted onto the inner sleeve flange 22 and the outer sleeve flange 32. The inner sleeve 20 and the outer sleeve 30 are limited by the engagement of the concave toothed ring 62 with the inner sleeve tooth 23 and the outer sleeve tooth 34 respectively. The locking member 64 is provided with both the mounting lug 33 and the connecting lug 63 to lock and fix the inner sleeve 20 and the outer sleeve 30. During assembly, first place the sealing sleeve 50 inside the outer sleeve 30, then insert the inner sleeve 20 and tighten it. Next, use appropriate force to pull or rotate the bent pipe sealing clamp 5 to feel the clamping force. After the high-pressure sealing test is qualified, put on the locking ring 61 to lock it. In actual design, the inner sleeve 20 is pre-tightened at a 15° angle, which corresponds to a diameter shrinkage of about 0.02mm for the sealing sleeve 50.

[0042] In this optional solution, such as Figure 4 and Figure 5As shown, the outer sleeve 31 is also machined with a through-hole 301 for oil leakage collection. The oil leakage collection hole 301 is located between the outer sleeve flange 32 and the mounting lug 33. The oil leakage collection hole 301 is used to collect the lubricating oil leaking between the elbow sealing clamp 5 and the inner lubricating elbow 3, and to determine whether the inner sleeve 20 is tightened properly. In this optional solution, an oil leakage collection hole 301 is drilled in the outer sleeve 31. When the sealing connection between the inner sleeve 21 and the outer sleeve 31 is unreliable, the collected leaking oil can only flow out from the oil leakage collection hole 301. Therefore, the reliability of the conical sealing connection between the inner sleeve 21 and the outer sleeve 31 can be determined by whether there is lubricating oil leakage through the oil leakage collection hole 301. Thus, the troubleshooting measure is very simple: just continue to tighten the inner sleeve 20. On the other hand, by adding the oil leakage collection hole 301, research can be conducted on the high-pressure sealing test method of the inner lubricating elbow 3, and the assembly inspection method can be improved to eliminate leakage in the hydraulic test stage, thereby improving the assembly quality.

[0043] In this optional solution, such as Figure 4 As shown, the self-locking sleeve and nut assembly 40 includes a nut 41 and a self-locking sleeve 42 fixed in the inner hole of the nut 41. One end of the self-locking sleeve 42 is open, and the other end protrudes towards the center to form a limiting protrusion ring 43. The inner wall of the self-locking sleeve 42 is provided with internal threads. The self-locking sleeve 42 is installed on the outer circle of the oil outlet end of the external oil pipe 4, and the limiting protrusion ring 43 abuts against the limiting step on the outer circle of the external oil pipe 4. The internal thread of the self-locking sleeve 42 is connected to the external thread of the connecting section on the inner sleeve 21. During the rotation of the self-locking sleeve and nut assembly 40, the limiting protrusion ring 43 abuts against the limiting step to gradually press the external oil pipe 4 axially into the inner sleeve 21. In the existing technology, although the sealing ring, fuse, and locking plate technologies are mature and the manufacturing cost is low, the debugging process is inconvenient, the delivery and commissioning time is long, the maintenance time is long, and the total cost is indirectly increased. Moreover, cutting the sealing ring, unscrewing the fuse, and breaking the locking plate lug will generate excess material that is difficult to remove. In the structure of this invention, the outer end oil pipe joint of the bent pipe sealing clamp 5 adopts a self-locking screw sleeve and nut combination 40, avoiding the use of fuses or locking plates, thereby reducing consumable parts and meeting the requirement of one-time installation and one-time testing delivery.

[0044] In this optional solution, the sealing sleeve 50 is made of Teflon or copper, and its outer surface is electroplated with a softer metal. The outer diameter of the oil inlet end of the internal lubricating bend is ground round and then electroplated with silver. In this optional solution, the selection of materials and electroplating layers for the sealing sleeve 50 should facilitate easy assembly, provide an appropriate range of adjustable tightening torque, maintain a seal over long-term use, prevent adhesion and corrosion, thereby improving the engine's test run pass rate and reliability. In this optional solution, the sealing sleeve 50 can be made of Teflon or pure copper with gold plating, resulting in a smooth and soft surface, long-lasting sealing effect, high cleanliness, reflecting the engine's high quality, and requiring less routine maintenance. Correspondingly, the outer diameter of the oil inlet end of the internal lubricating bend is ground round and then electroplated with silver. The locking ring is made of engineering plastic injection molding, which has a lower manufacturing cost than aluminum alloy, good corrosion resistance, and is lightweight.

[0045] Optionally, such as Figure 4 As shown, the bend sealing clamp 5 also includes a retaining ring 70, a first sealing ring 80, and a second sealing ring 90. The retaining ring 70 is fitted onto the outer circumference of the oil outlet end of the external oil pipe 4, with one side abutting against the limiting step and the other side abutting against the limiting protrusion 43. In this optional scheme, the retaining ring 70 indirectly applies the flexible force to the external oil pipe 4, avoiding direct force damage to the external oil pipe 4, thereby improving the service life of the external oil pipe 4. The first sealing ring 80 is fitted onto the outer circumference of the oil outlet end of the external oil pipe 4 and is located between the external oil pipe 4 and the inner sleeve 21. The first sealing ring 80 is used to seal the gap between the external oil pipe 4 and the inner sleeve 20, preventing lubricating oil from leaking through the gap between the two. The second sealing ring 90 is fitted onto the outer circumference of the lower clamping section of the inner sleeve 21 and is clamped between the end of the outer sleeve 31 and the inner sleeve flange 22. In order to collect leaked lubricating oil and facilitate maintenance, a fluororubber ring, i.e., the second sealing ring 90, is installed at the root of the inner sleeve 20 to block the outlet of the outer sleeve 30.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A rear bearing lubrication circuit structure, characterized in that, include: Rear bearing support (1), rear bearing (2) set in rear bearing support (1) to be lubricated, internal lubricating oil bend (3) for guiding lubricating oil to lubricate rear bearing (2), external oil pipe (4) arranged outside rear bearing support (1), and bend sealing clamp (5) for connecting internal lubricating oil bend (3) and external oil pipe (4). The internal lubricating oil bend (3) is installed inside the rear bearing support (1), and the lower oil outlet end of the internal lubricating oil bend (3) is connected to the rear bearing (2) through the lubricating oil flow path (101) provided inside the rear bearing support (1), and its corresponding upper oil inlet end extends upward to the upper outlet opened at the top of the rear bearing support (1). The bend sealing clamp (5) is installed in the upper outlet, and the two ends of the bend sealing clamp (5) are respectively fitted onto the oil inlet end of the inner lubricating bend (3) and the oil outlet end of the outer oil pipe (4) so ​​that during the rotation of the bend sealing clamp (5), the bend sealing clamp (5) gradually seals and clamps the inner lubricating bend (3), or gradually seals and clamps the oil outlet end of the outer oil pipe (4) into the bend sealing clamp (5). The bend sealing clamp (5) includes an inner sleeve (20), an outer sleeve (30) and a self-locking screw nut assembly (40) that are fitted together, as well as a sealing sleeve (50) and a locking ring assembly (60); The sealing sleeve (50) is made of Teflon or copper, and the outer surface of the sealing sleeve (50) is electroplated with a relatively soft metal; the outer circle of the oil inlet end of the internal lubricating bend is ground round and then electroplated with silver. The diameter of the internal lubricating oil bend (3) is smaller than that of the existing external insertion type straight pipe; The self-locking nut and sleeve assembly (40) includes a nut (41) and a self-locking sleeve (42) fixed in the inner hole of the nut (41). One end of the self-locking sleeve (42) is open, and the other end protrudes toward the center to form a limiting ring (43). The inner wall of the self-locking sleeve (42) is provided with internal threads. The bend sealing clamp (5) also includes a retaining ring (70), a first sealing ring (80) and a second sealing ring (90); the retaining ring (70) is fitted on the outer circle of the oil outlet end of the external oil pipe (4), and one side abuts against the limiting step for limiting, while the other side abuts against the limiting protrusion (43).

2. The rear bearing lubrication circuit structure according to claim 1, characterized in that, The internal lubricating bend (3) includes a vertically arranged lower section and an upper section that transitions to the top of the lower section and extends upward at an angle; After the lower section passes through the hollow support plate (102) of the rear bearing support (1), it is connected to the flange bolt joint (6) set in the lubricating oil flow path (101). The upper outlet is inclined, with the upper section extending upwards into the upper outlet. The bend sealing clamp (5) is installed at an angle in the upper outlet, and the lower clamping end clamps the upper section, while the corresponding upper connecting end extends out of the rear bearing support (1) and connects to the external oil pipe (4).

3. The rear bearing lubrication circuit structure according to claim 1, characterized in that, The sealing sleeve (50) is fitted onto the outer circle of the oil inlet end of the internal lubricating bend (3) and installed inside the outer sleeve (30); The lower clamping section of the inner sleeve (20) is inserted into the outer sleeve (30) and threadedly connected to the outer sleeve (30) so that during the rotation of the inner sleeve (20), the lower clamping section of the inner sleeve (20) gradually clamps the sealing sleeve (50) inward, thereby causing the sealing sleeve (50) to gradually clamp the internal lubricating oil bend (3). The locking ring assembly (60) is respectively installed on the outer circle of the inner sleeve (20) and the outer sleeve (30) to lock the inner sleeve (20) and the outer sleeve (30) after they have been rotated into place; The oil outlet end of the external oil pipe (4) is inserted into the upper connecting section of the inner sleeve (20). The self-locking nut assembly (40) is installed on the external oil pipe (4) and threadedly connected to the outer circular surface of the upper connecting section of the inner sleeve (20) so that the external oil pipe (4) is gradually sealed and tightened into the upper connecting section of the inner sleeve (20) during the rotation of the self-locking nut assembly (40).

4. The rear bearing lubrication circuit structure according to claim 3, characterized in that, The inner sleeve (20) includes a hollow tubular inner sleeve (21), and external threads are machined on the outer circles at both ends of the inner sleeve (21); The outer sleeve (30) includes a hollow tubular outer sleeve (31), and the inner wall of the outer sleeve (31) is machined with an internal thread that matches the external thread on the outer circle of the lower clamping section of the inner sleeve (21); The inner sleeve (21) is screwed into the outer sleeve (31) through the external thread on its lower clamping section, and the port of the lower clamping section is wrapped with the sealing sleeve (50) so that as the inner sleeve (21) continues to rotate, the port of the lower clamping section gradually clamps the sealing sleeve (50) inward.

5. The rear bearing lubrication circuit structure according to claim 4, characterized in that, The sealing sleeve (50) is a hollow cylindrical shape, with its inner shaft hole being a through hole of equal diameter, and its outer circular surface gradually shrinking from the middle to both ends to form an outer conical surface; The inner wall surface at the lower clamping section port of the inner sleeve (21) is an inner conical surface that adapts to the outer conical surface at one end of the sealing sleeve (50), and the inner wall surface at the lower clamping section port of the outer sleeve (31) is an inner conical surface that adapts to the outer conical surface at the other end of the sealing sleeve (50), so that during the rotation of the inner sleeve (21), the outer conical surfaces at both ends of the sealing sleeve (50) gradually come into contact with the inner conical surface of the inner sleeve (21) and the inner conical surface of the outer sleeve (31) to form a conical surface fit.

6. The rear bearing lubrication circuit structure according to claim 4, characterized in that, The inner sleeve (20) also includes an inner sleeve flange (22) provided on the outer circle of the middle part of the inner sleeve tube (21), and inner sleeve protrusion teeth (23) are provided on the outer circle surface of the inner sleeve flange (22) and are evenly distributed in the circumferential direction and protruding outward. The outer sleeve (30) also includes an outer sleeve flange (32) and a mounting lug (33) arranged sequentially on the outer circle of the connecting section of the outer sleeve tube (31). The outer circle of the outer sleeve flange (32) is provided with outer sleeve teeth (34) that are evenly distributed in the circumferential direction and protrude outward. The locking ring assembly (60) includes a hollow annular locking ring (61), a connecting lug (63) connected to the outer circle of the locking ring (61), and a locking member (64). The inner circle surface of the locking ring (61) is provided with a concave toothed ring (62) that engages with the inner sleeve tooth (23) and the outer sleeve tooth (34) respectively. The locking ring (61) is respectively fitted onto the inner sleeve flange (22) and the outer sleeve flange (32). The inner sleeve (20) and the outer sleeve (30) are limited by the engagement of the concave toothed ring (62) with the inner sleeve tooth (23) and the outer sleeve tooth (34) respectively. The locking member (64) is simultaneously provided with the mounting lug (33) and the connecting lug (63) to lock and fix the inner sleeve (20) and the outer sleeve (30).

7. The rear bearing lubrication circuit structure according to claim 6, characterized in that, The outer sleeve (31) is also machined with a through oil drain hole (301), which is located between the outer sleeve flange (32) and the mounting lug (33); The oil leakage collection hole (301) is used to collect the lubricating oil leaked between the elbow sealing clamp (5) and the internal lubricating oil elbow (3) and to determine whether the inner sleeve (20) is tightened in place.

8. The rear bearing lubrication circuit structure according to claim 4, characterized in that, The self-locking sleeve (42) is installed on the outer circle of the oil outlet end of the external oil pipe (4), and the limiting protrusion (43) abuts against the limiting step on the outer circle of the external oil pipe (4). The internal thread of the self-locking sleeve (42) is connected to the external thread of the connecting section on the inner sleeve (21). During the rotation of the self-locking sleeve and nut assembly (40), the limiting protrusion (43) abuts against the limiting step, so as to gradually press the external oil pipe (4) axially into the inner sleeve (21).

9. The rear bearing lubrication circuit structure according to claim 6, characterized in that, The first sealing ring (80) is fitted onto the outer circle of the oil outlet end of the external oil pipe (4) and is located between the external oil pipe (4) and the inner sleeve (21); The second sealing ring (90) is fitted onto the outer circle of the lower clamping section of the inner sleeve (21) and is clamped between the end of the outer sleeve (31) and the inner sleeve flange (22).

Images