A heat-insulating and pressure-resistant engine vibration damper mounting structure

Abstract

This invention discloses a heat-insulating and pressure-resistant engine vibration damper mounting structure, including a rear vibration damper. The rear vibration damper includes a rubber assembly one, a rubber assembly two, a main support assembly, and a mounting bracket assembly. One end of the mounting bracket assembly is inserted into the main support assembly. A main bolt passes through the rubber assembly two, the main support assembly, and the rubber assembly one in sequence and is then locked with a nut. The main bolt passing through the main support assembly is connected to one end of the mounting bracket assembly via a ball bearing one. The mounting bracket assembly includes a mounting bracket frame, and an engine connecting arm is provided on the turboprop engine. The heat-insulating connection method involves placing a high-strength heat insulation sheet between the engine connecting arm and the mounting bracket frame. During connection, a screw passes through the engine connecting arm, the high-strength heat insulation sheet, and the mounting bracket frame and is then locked with a locking nut, thereby connecting the turboprop engine to the rear vibration damper. After connection, the engine connecting arm and the mounting bracket frame are separated by the high-strength heat insulation sheet.

Description

Technical Field

[0001] This invention relates to a heat-insulating and pressure-resistant engine vibration damper mounting structure, belonging to the field of turboprop engine vibration reduction technology. Background Technology

[0002] A turboprop engine is an engine that combines jet thrust and propeller thrust, integrating the characteristics of both engines. This results in superior performance in low-speed flight and short takeoff and landing. Therefore, turboprop engines are widely used in small aircraft, helicopters, drones, and other aircraft.

[0003] When a turboprop engine is operating, the rotation of the propeller generates significant vibrations, making vibration issues more pronounced compared to other types of aircraft engines. Vibration adversely affects the engine's performance, potentially leading to wear and fatigue of engine components, thus shortening its service life. Simultaneously, vibration can damage the aircraft's structure, such as inducing structural fatigue cracks, thereby jeopardizing the airframe's lifespan and safety. Therefore, vibration dampers are typically installed between the engine and the aircraft frame to absorb and isolate vibration energy.

[0004] Along the length of the turboprop engine, the side closer to the turboprop is designated as the front side of the engine, and the opposite side is designated as the rear side. After the vibration dampers are installed, they can be classified into front vibration dampers, upper front vibration dampers, and rear vibration dampers according to their position relative to the engine.

[0005] In the design of the connection structure between the rear shock absorber and the engine for turboprop engines, heat insulation is a crucial consideration. This design is primarily based on the fact that turboprop engines generate a significant amount of heat during operation. If this heat is directly transferred to the shock absorber, it could lead to a decrease in the shock absorber's performance or even damage.

[0006] Chinese invention patent application CN116039935A, published on May 2, 2023, discloses a vibration damping mounting system for a large turboprop passenger aircraft engine. The system includes: a turboprop engine with a front mounting surface near the propeller and a rear mounting surface near the turbine combustion chamber; the front mounting surface has two mounting points and three front mounting sections; the rear mounting surface has two rear mounting sections; and mechanical or hydraulic torque compensation devices are installed at the two mounting points. The three front mounting sections include a first front mounting section and two second front mounting sections. The first front mounting section is located at the apex of the front mounting surface, and the two second front mounting sections are symmetrically arranged along the longitudinal vertical plane of the engine. A front upper vibration damping device is installed at the first front mounting section, and a front side vibration damping device is installed at the second front mounting sections. The two rear mounting sections are symmetrically arranged along the longitudinal vertical plane of the engine, and rear side vibration damping devices are installed at the two rear mounting sections.

[0007] The patent document does not disclose in detail how the rear shock absorber is connected to the engine.

[0008] In summary, designing a heat-insulating and pressure-resistant engine damper mounting structure that can isolate the large amount of heat generated by the turboprop engine during operation and prevent this heat from being directly transferred to the rear damper, thus ensuring the performance and service life of the rear damper, is an urgent technical problem to be solved. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to address the deficiencies in the prior art by providing a heat-insulating and pressure-resistant engine vibration damper mounting structure, which can isolate the large amount of heat generated by the turboprop engine during operation, prevent this heat from being directly transferred to the rear vibration damper, and ensure the performance and service life of the rear vibration damper.

[0010] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a heat-insulating and pressure-resistant engine shock absorber mounting structure, including a rear shock absorber, wherein the rear shock absorber includes a rubber component one, a rubber component two, a main support assembly disposed between the rubber component one and the rubber component two, and a mounting bracket assembly disposed on one side of the main support assembly. One end of the mounting bracket assembly is inserted into the main support assembly, and a main bolt is used to sequentially pass through the rubber component two, the main support assembly, and the rubber component one and then lock it with a nut, thereby pressing the rubber component two and the rubber component one onto the bottom and top surfaces of the main support assembly, so that the rubber component two and the rubber component one... The rubber body in the first part is in a pre-compressed state. The main bolt passing through the main support assembly is connected to one end of the mounting bracket assembly through a ball bearing. The mounting bracket assembly includes a mounting bracket frame and an engine connecting arm is provided on the turboprop engine. The heat insulation connection method is to set a high-strength heat insulation sheet between the engine connecting arm and the other end of the mounting bracket frame. During installation, screws are passed through the engine connecting arm, the high-strength heat insulation sheet and the other end of the mounting bracket frame and then locked with a lock nut, thereby connecting the turboprop engine and the rear shock absorber. After installation, the engine connecting arm and the mounting bracket frame are separated by the high-strength heat insulation sheet.

[0011] Preferably, the high-strength heat insulation sheet is made of mica sheet or ceramic fiber sheet.

[0012] Preferably, a step portion one is provided on the other end of the mounting frame, and a step portion two is provided on one end of the engine connecting arm;

[0013] During connection, the first step and the second step are positioned opposite each other to form an installation space between them. The high-strength heat insulation sheet is placed in the installation space, and then screws are passed through the engine connecting arm, the high-strength heat insulation sheet and the other end of the mounting frame and locked with a locking nut to connect the turboprop engine and the rear shock absorber.

[0014] Preferably, a ball bearing mounting hole is provided at one end of the mounting frame. The main support assembly includes a main support frame, and a through hole is provided at the middle position of the main support frame. When one end of the mounting frame assembly is inserted into one side of the main support assembly, the central axis of the ball bearing mounting hole coincides with the central axis of the through hole. After installation, the ball bearing is positioned between the outside of the main bolt and the ball bearing mounting hole, so that the main bolt passing through the main support assembly is connected to one end of the mounting frame assembly through the ball bearing.

[0015] Two bushings are fitted around the main bolt: bushing one and bushing two; bushing one is located between rubber assembly one and ball bearing one, and bushing two is located between rubber assembly two and ball bearing one; both bushing one and bushing two are located in through hole three, and there is a gap H4 between the outer circumferential surface of bushing one and the inner circumferential surface of through hole three, and there is a gap H5 between the outer circumferential surface of bushing two and the inner circumferential surface of through hole three.

[0016] When subjected to excessive impact or vibration, a rigid limiting structure is formed through the contact between the outer circumferential surfaces of bushing one and bushing two and the inner circumferential surface of through hole three.

[0017] Preferably, a second ball bearing mounting hole and a third ball bearing mounting hole are provided on the other side of the main support assembly, wherein the ball bearing in the first screw with ball bearing is the second ball bearing, and the ball bearing in the second screw with ball bearing is the third ball bearing;

[0018] After installation, ball bearing 2 is positioned between one end of screw 1 and the mounting hole of ball bearing 2, so that one end of screw 1 is connected to the other side of the main support assembly through ball bearing 2. Ball bearing 3 is positioned between one end of screw 2 and the mounting hole of ball bearing 3, so that one end of screw 2 is connected to the other side of the main support assembly through ball bearing 3. The other ends of both screw 1 and screw 2 are connected to the aircraft frame.

[0019] Preferably, a mounting arm one and a mounting arm two are provided on the aircraft frame, a mounting through hole one is provided at one end of the mounting arm one, and a mounting through hole two is provided at one end of the mounting arm two;

[0020] During connection, the other end of screw one is passed through mounting through hole one and locked with mounting nut one, and the other end of screw two is passed through mounting through hole two and locked with mounting nut two, so that the other ends of screw one and screw two are connected to the aircraft frame.

[0021] Preferably, both the second rubber component and the first rubber component include a top plate, a bottom plate, and a bottom plate. The rubber body in both the second rubber component and the first rubber component includes a rubber stack and a rubber stack. The bottom plate is vulcanized and bonded to the top plate through the rubber stack, and the bottom plate is vulcanized and bonded to the top plate through the rubber stack. The rubber stack and the rubber stack are located at both ends of the top plate, and a through hole is opened in the middle of the top plate.

[0022] During installation, the main bolt passes through the through hole of rubber component two, the through hole of the main support component, and the through hole of rubber component one in sequence, and is then locked with the nut. After locking, the bottom plate one and bottom plate two of rubber component two contact the bottom surface of the main support component, and the bottom plate one and bottom plate two of rubber component one contact the top surface of the main support component.

[0023] Preferably, before pre-compression, one end of the bushing one contacts the top plate of the rubber assembly one, and the other end of the bushing one has a gap H1 between it and the end face of the inner ring of the ball bearing one. One end of the bushing two contacts the top plate of the rubber assembly two, and the other end of the bushing two has a gap H2 between it and the end face of the inner ring of the ball bearing one. After the main bolt is tightened for pre-compression, both gaps H1 and H2 are zero. By designing the values ​​of gaps H1 and H2, the pre-compression amount of the rubber bodies in the rubber assembly two and the rubber assembly one can be controlled.

[0024] The beneficial effects of this invention are as follows: A high-strength heat insulation sheet made of mica or ceramic fiber is used between the engine connecting arm and the other end of the mounting frame. This not only isolates the large amount of heat generated by the turboprop engine during operation, preventing this heat from being directly transferred to the rear shock absorber and ensuring its performance and service life, but also ensures the stability of the bolted connection structure. By setting mutually cooperating stepped portions, the high-strength heat insulation sheet can be positioned during connection, improving work efficiency and ensuring connection quality. When subjected to excessive impact or vibration, a rigid limiting structure is formed by the contact between the outer circumferential surfaces of bushing one and bushing two and the inner circumferential surface of through hole three. This allows the invention to limit the deformation of the shock absorber under excessive impact or vibration, thereby protecting the shock absorber and engine from damage and ensuring that the shock absorber operates within a predetermined stroke range, avoiding malfunctions or damage caused by exceeding the design range. By designing two ball-bearing screws (one and two) on the side of the rear shock absorber to connect the main support assembly to the aircraft frame, the rear shock absorber gains more installation redundancy in all directions, compensating for installation gaps and improving the safety, reliability, and convenience of installation and use. The main bolt is positioned between the two rubber stacks of rubber assembly one and rubber assembly two. This allows for pre-compression of the rubber bodies in rubber assembly two and rubber assembly one by pressing them against the bottom and top surfaces of the main support assembly with a single main bolt. Compared to existing technologies, this reduces the number of connecting bolts, simplifies the pre-compression structure of the rubber components, simplifies the installation process, and reduces the overall weight of the rear shock absorber, meeting lightweight design requirements. Furthermore, this design reduces the area of ​​the third metal frame in existing technologies, further reducing the overall weight of the rear shock absorber. By using positioning protrusions and through holes to assemble the rubber components and main support components, the assembly accuracy and speed of the rear shock absorber can be further improved. In addition, the weight of the main support frame can be reduced by the through holes one and two, thereby further meeting the requirements of lightweight design. Attached Figure Description

[0025] Figure 1 This is a three-dimensional structural diagram of the rear shock absorber connected to the turboprop engine in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the exploded disassembly structure of the rear shock absorber in an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the axial cross-sectional structure of the rear shock absorber in an embodiment of the present invention;

[0028] Figure 4 This is a three-dimensional structural diagram of the main support assembly in an embodiment of the present invention;

[0029] Figure 5 This is a three-dimensional structural diagram of the mounting bracket assembly of the rear shock absorber connected to the turboprop engine in an embodiment of the present invention;

[0030] Figure 6 for Figure 3 A schematic diagram of a partial axial section of the structure located at the main bolt;

[0031] Figure 7 for Figure 6 Enlarged structural diagram of section A in the middle;

[0032] Figure 8 This is a three-dimensional structural diagram of the installation connection between the main support assembly and the aircraft frame in an embodiment of the present invention.

[0033] Figure 9 This is a three-dimensional structural diagram of rubber component one in an embodiment of the present invention. Figure 1 ;

[0034] Figure 10 This is a top view of the rear shock absorber in an embodiment of the present invention;

[0035] Figure 11 This is a three-dimensional structural diagram of rubber component one in an embodiment of the present invention. Figure 2 ;

[0036] Figure 12 for Figure 6 Enlarged structural diagram of section B;

[0037] In the diagram: 1. Rubber component one, 2. Rubber component two, 3. Main support assembly, 311. Main support frame, 312. Through hole three, 313. Swing arm, 314. Connecting arm, 315. Lug, 316. Ball bearing two mounting hole, 317. Ball bearing three mounting hole, 318. Through hole one, 319. Through hole two, 4. Mounting bracket assembly, 411. Mounting bracket frame, 412. Ball bearing one mounting hole, 413. Step part one, 5. Main bolt, 6. Nut, 7. Ball bearing one, 711. Inner ring, 8. Screw one, 9. Screw two, 10. Screw, 1 1. Bushing 1, 12. Bushing 2, 13. Aircraft frame, 131. Mounting arm 1, 132. Mounting arm 2, 14. Mounting nut 1, 15. Mounting nut 2, 16. Connecting pin, 17. Ball bearing 2, 18. Ball bearing 3, 19. Top plate, 191. Countersunk hole, 20. Base plate 1, 21. Base plate 2, 22. Rubber stack 1, 23. Rubber stack 2, 24. Positioning protrusion 1, 25. Positioning protrusion 2, 26. Flange, 27. Through hole, 28. Engine connecting arm, 281. Step 2, 29. High-strength heat insulation sheet, 30. Locking nut. Detailed Implementation

[0038] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Example: Figures 1 to 3 As shown, this embodiment discloses a heat-insulating connection method for a rear-side vibration damper of a turboprop engine. The rear-side vibration damper includes a rubber assembly 1, a rubber assembly 2, a main support assembly 3 disposed between the rubber assembly 1 and the rubber assembly 2, and a mounting bracket assembly 4 disposed on one side of the main support assembly 3. One end of the mounting bracket assembly 4 is inserted into the main support assembly 3. A main bolt 5 passes through the rubber assembly 2, the main support assembly 3, and the rubber assembly 1 in sequence and is then locked with a nut 6, thereby pressing the rubber assembly 2 and the rubber assembly 1 against the bottom and top surfaces of the main support assembly 3, so that the rubber bodies in the rubber assembly 2 and the rubber assembly 1 are in a pre-compressed state. The main bolt 5 passing through the main support assembly 3 is connected to one end of the mounting bracket assembly 4 through a ball bearing 7. The other end of the mounting bracket assembly 4 is connected to the turboprop engine (not shown in the figure), and the other side of the main support assembly 3 is connected to the aircraft frame (not shown in the figure) through a screw 8 with a ball bearing and a screw 9 with a ball bearing. By installing the aforementioned rear-side vibration damper between the turboprop engine and the aircraft frame to absorb and isolate vibration energy, the service life of the turboprop engine is improved, ensuring the safety of the aircraft body.

[0040] like Figure 4 and Figure 5As shown, the mounting bracket assembly 4 includes a mounting bracket frame 411, with a ball bearing mounting hole 412 provided at one end of the mounting bracket frame 411; the main support assembly 3 includes a main support frame 311, with a through hole 312 provided at the middle position of the main support frame 311; as shown... Figure 3 As shown, when one end of the mounting bracket assembly 4 is inserted into one side of the main support assembly 3, the central axis of the ball bearing mounting hole 412 coincides with the central axis of the through hole 312; after installation, the ball bearing 7 is positioned between the outside of the main bolt 5 and the ball bearing mounting hole 412, so that the main bolt 5 passing through the main support assembly 3 is connected to one end of the mounting bracket assembly 4 through the ball bearing 7. Figure 5 As shown, an engine connecting arm 28 is provided on the turboprop engine. A high-strength heat insulation plate 29 is provided between the engine connecting arm 28 and the other end of the mounting frame 411. A screw 10 is passed through the engine connecting arm 28, the high-strength heat insulation plate 29, and the other end of the mounting frame 411, and then locked with a locking nut 30, thereby connecting the turboprop engine to the rear shock absorber. After connection, the engine connecting arm and the mounting frame are separated by the high-strength heat insulation plate. Here, since the engine and the rear shock absorber use a bolted connection structure, the heat insulation plate must be able to insulate heat and withstand the pressure of bolt tightening, requiring sufficient strength. Therefore, in this embodiment, a high-strength heat insulation plate is used between the engine connecting arm and the other end of the mounting frame. This not only isolates the large amount of heat generated by the turboprop engine during operation, preventing this heat from being directly transferred to the rear shock absorber, ensuring the performance and service life of the rear shock absorber, but also ensures the stability of the bolted connection structure. In this embodiment, the high-strength heat insulation sheet 29 can be made of mica sheet or ceramic fiber sheet.

[0041] like Figure 5 As shown, a step 413 is provided on one end of the mounting frame 411, and a step 281 is provided on one end of the engine connecting arm 28. During connection, the step 413 and the step 281 are positioned opposite each other to form an installation space. The high-strength heat insulation sheet 29 is placed in the installation space, and then screws 10 are passed through the engine connecting arm 28, the high-strength heat insulation sheet 29, and the other end of the mounting frame 411 and locked with locking nuts 30, thereby connecting the turboprop engine to the rear shock absorber. By setting mutually cooperating steps, the high-strength heat insulation sheet can be positioned during connection, improving work efficiency and ensuring connection quality.

[0042] like Figure 6 and Figure 7As shown, bushing 11 and bushing 2 12 are also sleeved on the outside of the main bolt 5. Bushing 11 is located between rubber assembly 1 and ball bearing 7, and bushing 2 12 is located between rubber assembly 2 and ball bearing 7. Both bushing 11 and bushing 2 12 are located in through hole 312, and a gap H4 is left between the outer circumferential surface of bushing 11 and the inner circumferential surface of through hole 312, and a gap H5 is left between the outer circumferential surface of bushing 2 12 and the inner circumferential surface of through hole 312. When subjected to excessive impact or vibration, a rigid limiting structure is formed by the contact between the outer circumferential surface of bushing 11 and the outer circumferential surface of bushing 2 12 and the inner circumferential surface of through hole 312. This allows the embodiment to limit the deformation of the shock absorber when subjected to excessive impact or vibration, thereby protecting the shock absorber and engine from damage, ensuring that the shock absorber works within the predetermined stroke range, and avoiding failure or damage caused by exceeding the design range.

[0043] like Figure 4 and Figure 8 As shown, a second ball bearing mounting hole 316 and a third ball bearing mounting hole 317 are provided on the other side of the main support assembly 3. The ball bearing in the first screw 8 with a ball bearing is the second ball bearing 17, and the ball bearing in the second screw 9 with a ball bearing is the third ball bearing 18. After installation, the second ball bearing 17 is positioned between one end of the first screw 8 and the second ball bearing mounting hole 316, so that one end of the first screw 8 is connected to the other side of the main support assembly 3 through the second ball bearing 17. The third ball bearing 18 is positioned between one end of the second screw 9 and the third ball bearing mounting hole 317, so that one end of the second screw 9 is connected to the other side of the main support assembly 3 through the third ball bearing 18. The other ends of both the first screw 8 and the second screw 9 are connected to the aircraft frame 13. Thus, through the above structure, the other side of the main support assembly 3 is connected to the aircraft frame 13 through the first screw 8 with a ball bearing and the second screw 9 with a ball bearing.

[0044] This embodiment connects the main support assembly to the aircraft frame by designing two screws with ball bearings, one with a ball bearing and the other with a ball bearing. This allows the rear shock absorber to have more installation redundancy in all directions, which can compensate for installation gaps and improve the safety, reliability and convenience of installing and using the rear shock absorber.

[0045] Mounting arm 131 and mounting arm 132 are provided on the aircraft frame 13. Mounting arm 131 has a mounting through hole 1 (not shown in the figure) at one end, and mounting arm 132 has a mounting through hole 2 (not shown in the figure) at one end. During connection, the other end of screw 8 is passed through mounting through hole 1 and locked with mounting nut 14, and the other end of screw 9 is passed through mounting through hole 2 and locked with mounting nut 25, so that the other ends of screw 8 and screw 9 are connected to the aircraft frame 13.

[0046] The main support assembly 3 also includes a rotating arm 313. A connecting arm 314 and a hanging ear 315 are provided on one side of the main support frame 311. The connecting arm 314 and the hanging ear 315 are integral with the main support frame 311. One end of the rotating arm 313 is hinged to the hanging ear 315 by a connecting pin 16. A second ball bearing mounting hole 316 is provided on the connecting arm 314, and a third ball bearing mounting hole 317 is provided on the other end of the rotating arm 313. Due to various factors, the relative positions of mounting through holes one and two on the aircraft frame 13 are uncertain. Therefore, in existing technologies, installation difficulties often arise during connection. In this embodiment, during installation, the screw 8 with ball bearing is first connected to the mounting arm. After connection, due to the hinge structure between the rotating arm 313 and the lug 315, the installation position of the screw 9 with ball bearing can be adjusted according to the actual position of the mounting through hole two. This allows the screw 9 with ball bearing to be easily connected to the mounting arm two, further improving the ease of installation and use of the rear shock absorber. In addition, the connecting arm 314 and the main support frame 311 are designed as an integral structure. Compared with existing technologies, this reduces one hinge point, making the rear shock absorber more stable during vibration damping operation.

[0047] The structures of rubber component 2 and rubber component 1 are the same. Taking rubber component 1 as an example, as follows: Figure 9 As shown, the rubber component 1 includes a top plate 19, a bottom plate 20, and a bottom plate 21. The rubber body includes a rubber stack 22 and a rubber stack 23. The bottom plate 20 is vulcanized and bonded to the top plate 19 via the rubber stack 22, and the bottom plate 21 is vulcanized and bonded to the top plate 19 via the rubber stack 23. The rubber stacks 22 and 23 are located at opposite ends of the top plate 19, and a through hole 27 is formed in the middle of the top plate 19. During installation, the main bolt 5 passes through the through hole 27 of the rubber component 2, the main support assembly 3, and the rubber component 1 in sequence, and is then locked with the nut 6. After locking, the bottom plates 20 and 21 of the rubber component 2 contact the bottom surface of the main support assembly 3, and the bottom plates 20 and 21 of the rubber component 1 contact the top surface of the main support assembly 3. Figure 10As shown, in this embodiment, the main bolt 5 is positioned between the two rubber stacks of rubber assembly 2 and rubber assembly 1. This allows for pre-compression of the rubber components in rubber assembly 2 and 1 by using only one main bolt 5 to press them firmly against the bottom and top surfaces of the main support assembly 3. Compared to existing technologies, this reduces the number of connecting bolts, simplifies the pre-compression structure of the rubber components, simplifies the installation process, and reduces the weight of the entire rear vibration damping device, thus meeting the requirements of lightweight design. Furthermore, this arrangement also reduces the area of ​​the third metal frame (i.e., the top plate in this embodiment) in existing technologies, further reducing the weight of the entire rear vibration damping device.

[0048] like Figure 4 and Figure 11 As shown, through holes 318 and 319 are also provided on the main support frame 311. Through holes 318 and 319 are located on both sides of through hole 312. Positioning protrusions 24 and 25 are respectively provided on the bottom plate 20 and bottom plate 21 of rubber component 2 and rubber component 1. The shapes of positioning protrusions 24 and 25 match those of through holes 318 and 319. When rubber component 2 and rubber component 1 are pressed onto the bottom and top surfaces of the main support assembly 3, the positioning protrusions 24 and 25 of rubber component 1 are inserted into one end of the through hole 318 and one end of the through hole 319 on the main support frame 311, respectively, and the positioning protrusions 24 and 25 of rubber component 2 are inserted into the other end of the through hole 318 and the other end of the through hole 319 on the main support frame 311, thereby positioning the rubber components 2 and 1 on the bottom and top surfaces of the main support assembly 3. This further improves the assembly accuracy and speed of the rear shock absorber. In addition, the through holes 1 and 2 also reduce the weight of the main support frame, thereby further meeting the requirements of lightweight design.

[0049] In addition, such as Figure 6 and Figure 7As shown, in order to further precisely control the pre-compression of the rubber bodies in rubber assembly 2 and rubber assembly 1, the applicant made further improvements. Before pre-compression, one end of bushing 11 contacts the top plate 19 of rubber assembly 1, and the other end of bushing 11 has a gap H1 between it and the end face of the inner ring 711 of ball bearing 7. One end of bushing 12 contacts the top plate 19 of rubber assembly 2, and the other end of bushing 12 has a gap H2 between it and the end face of the inner ring 711 of ball bearing 7. After the main bolt 5 is tightened for pre-compression, both gaps H1 and H2 are zero, that is, the other end of bushing 11 contacts the end face of the inner ring 711 of ball bearing 7, and the other end of bushing 12 contacts the end face of the inner ring 711 of ball bearing 7. By employing a rigid restraint between the bushing and the ball bearing, the pre-compression of the rubber components in rubber assembly one and two can be precisely controlled through the design of clearances H1 and H2. After the bolts and nuts reach the designed tightening torque, the bushing provides a rigid metallic restraint to ensure the rubber remains in its designed compressed state, preventing the rubber components from loosening under engine load conditions. Furthermore, it should be noted that after pre-compression, bushing one and bushing two can also be used to axially restrain the ball bearing.

[0050] like Figure 12 As shown, flanges 26 are provided on the outer circumferential surfaces of one end of bushing 11 and bushing 12. Countersunk holes 191 are provided on the top plates 19 of rubber assembly 1 and rubber assembly 2. When one end of bushing 11 and bushing 12 contacts the top plate 19, one end of bushing 11 and bushing 12 is inserted into the countersunk holes 191 on the top plates 19 of rubber assembly 1 and rubber assembly 2, respectively. The flanges 26 on one end of bushing 11 and bushing 12 contact the top plates 19 of rubber assembly 1 and rubber assembly 2, respectively. At this time, a gap H3 is left between one end of bushing 11 and bushing 12 and the bottom surface of the countersunk holes 191 on the top plates 19 of rubber assembly 1 and rubber assembly 2.

[0051] In summary, this invention employs a high-strength heat insulation sheet made of mica or ceramic fiber sheets between the engine connecting arm and the other end of the mounting frame. This effectively isolates the large amount of heat generated by the turboprop engine during operation, preventing it from being directly transferred to the rear shock absorber, thus ensuring the performance and service life of the rear shock absorber, and also ensuring the stability of the bolted connection structure. The use of mutually cooperating stepped sections allows for the positioning of the high-strength heat insulation sheet during connection, improving work efficiency and ensuring connection quality. When subjected to excessive impact or vibration, a rigid limiting structure is formed by the contact between the outer circumferential surfaces of bushing one and bushing two and the inner circumferential surface of through hole three. This allows the invention to limit the deformation of the shock absorber under excessive impact or vibration, thereby protecting the shock absorber and engine from damage and ensuring that the shock absorber operates within a predetermined stroke range, avoiding malfunctions or damage caused by exceeding the design limits. By designing two ball-bearing screws (one and two) on the side of the rear shock absorber to connect the main support assembly to the aircraft frame, the rear shock absorber gains more installation redundancy in all directions, compensating for installation gaps and improving the safety, reliability, and convenience of installation and use. The main bolt is positioned between the two rubber stacks of rubber assembly one and rubber assembly two. This allows for pre-compression of the rubber bodies in rubber assembly two and rubber assembly one by pressing them against the bottom and top surfaces of the main support assembly with a single main bolt. Compared to existing technologies, this reduces the number of connecting bolts, simplifies the pre-compression structure of the rubber components, simplifies the installation process, and reduces the overall weight of the rear shock absorber, meeting lightweight design requirements. Furthermore, this design reduces the area of ​​the third metal frame in existing technologies, further reducing the overall weight of the rear shock absorber. By using positioning protrusions and through holes to assemble the rubber components and main support components, the assembly accuracy and speed of the rear shock absorber can be further improved. In addition, the weight of the main support frame can be reduced by the through holes one and two, thereby further meeting the requirements of lightweight design.

[0052] In the embodiments, "multiple" refers to "two or more". The above embodiments are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the invention. Therefore, all equivalent technical solutions should also fall within the protection scope of the invention, which is defined by the claims.

Claims

1. A heat-insulating and pressure-resistant engine vibration damper mounting structure, comprising a rear vibration damper, the rear vibration damper comprising a rubber assembly one, a rubber assembly two, a main support assembly disposed between the rubber assembly one and the rubber assembly two, and a mounting bracket assembly disposed on one side of the main support assembly, the other side of the main support assembly being connected to an aircraft frame via a screw one with a ball bearing and a screw two with a ball bearing, the mounting bracket assembly comprising a mounting bracket frame, one end of the mounting bracket frame being inserted into the main support assembly, and a main bolt being used to sequentially pass through the rubber assembly two, the main support assembly, and the rubber assembly one before being locked with a nut, thereby pressing the rubber assembly two and the rubber assembly one onto the bottom and top surfaces of the main support assembly, so that the rubber bodies in the rubber assembly two and the rubber assembly one are in a pre-compressed state, the main bolt passing through the main support assembly being connected to one end of the mounting bracket assembly via a ball bearing one, characterized in that: An engine connecting arm is provided on the turboprop engine; a high-strength heat insulation plate is installed between the engine connecting arm and the other end of the mounting frame. During installation, screws are passed through the engine connecting arm, the high-strength heat insulation plate, and the other end of the mounting frame and then locked with lock nuts, thereby connecting the turboprop engine to the rear shock absorber; after installation, the engine connecting arm and the mounting frame are separated by the high-strength heat insulation plate. The high-strength heat insulation sheet is made of mica sheet or ceramic fiber sheet; A step portion one is provided on the other end of the mounting frame, and a step portion two is provided on one end of the engine connecting arm; During connection, the first step and the second step are positioned opposite each other to form an installation space between them. The high-strength heat insulation sheet is placed in the installation space, and then screws are passed through the engine connecting arm, the high-strength heat insulation sheet and the other end of the mounting frame and locked with a locking nut to connect the turboprop engine and the rear shock absorber.

2. The engine vibration damper mounting structure according to claim 1, characterized in that: A ball bearing mounting hole is provided at one end of the mounting frame. The main support assembly includes a main support frame, and a through hole is provided at the middle position of the main support frame. When one end of the mounting frame assembly is inserted into one side of the main support assembly, the central axis of the ball bearing mounting hole coincides with the central axis of the through hole. After installation, the ball bearing is positioned between the outside of the main bolt and the ball bearing mounting hole, so that the main bolt passing through the main support assembly is connected to one end of the mounting frame assembly through the ball bearing. Two bushings are fitted around the main bolt: bushing one and bushing two; bushing one is located between rubber assembly one and ball bearing one, and bushing two is located between rubber assembly two and ball bearing one; both bushing one and bushing two are located in through hole three, and there is a gap H4 between the outer circumferential surface of bushing one and the inner circumferential surface of through hole three, and there is a gap H5 between the outer circumferential surface of bushing two and the inner circumferential surface of through hole three. When subjected to excessive impact or vibration, a rigid limiting structure is formed by the contact between the outer circumferential surfaces of bushing one and bushing two and the inner circumferential surface of through hole three.

3. The engine vibration damper mounting structure according to claim 2, characterized in that: On the other side of the main support assembly, there are two mounting holes for ball bearing 2 and ball bearing 3. The ball bearing in the screw 1 with ball bearing is ball bearing 2, and the ball bearing in the screw 2 with ball bearing is ball bearing 3. After installation, ball bearing 2 is positioned between one end of screw 1 and the mounting hole of ball bearing 2, so that one end of screw 1 is connected to the other side of the main support assembly through ball bearing 2. Ball bearing 3 is positioned between one end of screw 2 and the mounting hole of ball bearing 3, so that one end of screw 2 is connected to the other side of the main support assembly through ball bearing 3. The other ends of both screw 1 and screw 2 are connected to the aircraft frame.

4. The engine vibration damper mounting structure according to claim 3, characterized in that: Mounting arm one and mounting arm two are provided on the aircraft frame. Mounting through hole one is provided at one end of mounting arm one, and mounting through hole two is provided at one end of mounting arm two. During connection, the other end of screw one is passed through mounting through hole one and locked with mounting nut one, and the other end of screw two is passed through mounting through hole two and locked with mounting nut two, so that the other ends of screw one and screw two are connected to the aircraft frame.

5. The engine vibration damper mounting structure according to claim 2, characterized in that: Both rubber component 2 and rubber component 1 include a top plate, a bottom plate 1 and a bottom plate 2. The rubber body in both rubber component 2 and rubber component 1 includes a rubber stack 1 and a rubber stack 2. The bottom plate 1 is vulcanized and bonded to the top plate through the rubber stack 1, and the bottom plate 2 is vulcanized and bonded to the top plate through the rubber stack 2. The rubber stack 1 and the rubber stack 2 are located at both ends of the top plate, and a through hole is opened in the middle of the top plate. During installation, the main bolt passes through the through hole of rubber component two, the through hole of the main support component, and the through hole of rubber component one in sequence, and is then locked with the nut. After locking, the bottom plate one and bottom plate two of rubber component two contact the bottom surface of the main support component, and the bottom plate one and bottom plate two of rubber component one contact the top surface of the main support component.

6. The engine vibration damper mounting structure according to claim 5, characterized in that: Before pre-compression, one end of bushing one contacts the top plate of rubber assembly one, and the other end of bushing one has a gap H1 between it and the end face of the inner ring of ball bearing one. One end of bushing two contacts the top plate of rubber assembly two, and the other end of bushing two has a gap H2 between it and the other end face of the inner ring of ball bearing one. After pre-compression by tightening the main bolt, both gaps H1 and H2 are zero. By designing the values ​​of gaps H1 and H2, the pre-compression amount of the rubber bodies in rubber assembly two and rubber assembly one can be controlled.

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