Turboprop engine arrangement method and vibration reduction system

Abstract

The invention discloses a turboprop engine arrangement method and a vibration reduction system, a turboprop engine is arranged through the vibration reduction system, and the vibration reduction system comprises a front side vibration damper, a front upper vibration damper and a rear side vibration damper which are installed between an aircraft frame and the turboprop engine; a torque compensation device is further arranged on the aircraft frame and connected with the front shock absorber. The turboprop engine arrangement method comprises the step of optimizing a pre-compression method of rubber assemblies in a rear shock absorber, that is, the rear shock absorber comprises a main support assembly, the rubber assemblies comprise the first rubber assembly and the second rubber assembly, and the main support assembly is arranged between the first rubber assembly and the second rubber assembly. A main bolt sequentially penetrates through the middle position of the second rubber assembly, the main support assembly and the middle position of the first rubber assembly and then is locked with a nut, so that the second rubber assembly and the first rubber assembly are tightly pressed on the bottom face and the top face of the main support assembly, and rubber bodies in the second rubber assembly and the first rubber assembly are in a pre-compressed state.

Description

Technical Field

[0001] The present invention relates to a turboprop engine arrangement method and a vibration damping system, and belongs to the technical field of turboprop engine vibration damping. Background Art

[0002] A turboprop engine is an engine that combines jet thrust and propeller thrust. It combines the characteristics of a jet engine and a propeller engine and has better performance in aspects such as low-speed flight and short takeoff and landing. Therefore, turboprop engines are widely used in aircraft such as small airplanes, helicopters, and unmanned aerial vehicles.

[0003] When a turboprop engine operates, due to the rotation of the propeller, a large vibration will be generated. Therefore, the vibration problem of a turboprop engine may be more prominent compared to other types of aeroengines. Vibration will have an adverse impact on the working performance of the engine itself, may cause wear and fatigue of engine components, thereby shortening its service life. At the same time, vibration will also damage the airframe structure of the aircraft, such as inducing structural fatigue cracks, etc., and then endangering the life and safety of the fuselage. Therefore, generally, a vibration damping system is installed between the engine and the aircraft frame to absorb and isolate vibration energy. In addition, due to the rotation of the propeller, a large torque will be brought to the turboprop engine. When installing the vibration damping system, it is necessary to synchronously consider the torsional resistance of the structure under large torsional conditions.

[0004] Chinese Patent Application Publication No. CN116039935A, published on May 2, 2023, discloses a vibration damping installation system for a large turboprop passenger aircraft engine, which includes: a turboprop engine, the turboprop engine having a front mounting surface close to the propeller side and a rear mounting surface close to the turbine combustion chamber side, two mounting points and three front mounting joints on the front mounting surface, and two rear mounting joints on the rear mounting surface. Among them, a mechanical or hydraulic torque compensation device is installed at the two mounting points; the three front mounting joints include a first front mounting joint and two second front mounting joints, the first front mounting joint is located at the vertex of the front mounting surface, the two second front mounting joints are symmetrically arranged on the left and right along the longitudinal vertical plane of the engine, a front upper vibration damping device is installed at the first front mounting joint, and a front side vibration damping device is installed at the second front mounting joint; the two rear mounting joints are symmetrically arranged on the left and right along the longitudinal vertical plane of the engine, and a rear side vibration damping device is installed at the two rear mounting joints.

[0005] Although the above patent document discloses a vibration damping installation system for a large turboprop passenger aircraft engine, some problems are still found in the actual use process, so it is necessary to further optimize its design.

[0006] In summary, how to design a turboprop engine layout method and a vibration damping system to further optimize the performance of the product, improve its practicality in propeller aircraft, and make it have a better application prospect is a technical problem that needs to be solved urgently. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a turboprop engine layout method and a vibration damping system to address the defects in the prior art. The method further optimizes the performance of the product, improves its practicality in propeller aircraft, and makes it have a better application prospect.

[0008] To solve the above technical problem, the technical solution adopted by the present invention is as follows: A turboprop engine layout method, in which the turboprop engine is arranged on the aircraft frame through a vibration damping system. The vibration damping system includes: two front-side shock absorbers and one front-upper shock absorber installed between the aircraft frame and the turboprop engine near the front side of the engine; two rear-side shock absorbers installed between the aircraft frame and the turboprop engine near the rear side of the engine; a torque compensation device is also provided on the aircraft frame at the front side of the engine, and the torque compensation device is connected to the two front-side shock absorbers; the two front-side shock absorbers and the two rear-side shock absorbers are respectively located on both sides of the turboprop engine, and the front-upper shock absorber is located at the top of the turboprop engine. The turboprop engine layout method includes optimizing the pre-compression method of the rubber components in the rear-side shock absorbers, that is: the rear-side shock absorbers further include a main support assembly, the rubber components include rubber component one and rubber component two, the main support assembly is arranged between rubber component one and rubber component two. During installation, the main bolt passes through the middle position of rubber component two, the main support assembly, and the middle position of rubber component one in sequence and is locked with a nut, so as to press rubber component two and rubber component one against the bottom surface and the top surface of the main support assembly, making the rubber bodies in rubber component two and rubber component one in a pre-compressed state.

[0009] Preferably, both rubber component two and rubber component one include a top plate, a bottom plate one, and a bottom plate two. The rubber bodies in rubber component two and rubber component one both include rubber stack one and rubber stack two. The bottom plate one is vulcanized and bonded to the top plate through rubber stack one, and the bottom plate two is vulcanized and bonded to the top plate through rubber stack two. Rubber stack one and rubber stack two are respectively located at both ends of the top plate, and a through hole is opened at the middle position of the top plate; During installation, the main bolt passes through the through holes of rubber component two, the main support assembly, and the through holes of rubber component one in sequence and is locked with a nut. After locking, the bottom plate one and the bottom plate two of rubber component two are in contact with the bottom surface of the main support assembly, and the bottom plate one and the bottom plate two of rubber component one are in contact with the top surface of the main support assembly.

[0010] Preferably, the main bolt passing through the main support assembly is cooperatively connected with one end of the mounting frame assembly through a first ball bearing. An outer sleeve one and an outer sleeve two are also sleeved outside the main bolt. The outer sleeve one is located between the top plate of the first rubber assembly and the first ball bearing, and the outer sleeve two is located between the top plate of the second rubber assembly and the first ball bearing. Before pre-compression, one end of the outer sleeve one contacts the top plate of the first rubber assembly, and a gap H1 is left between the other end of the outer sleeve one and one end face of the inner ring of the first ball bearing. One end of the outer sleeve two contacts the top plate of the second rubber assembly, and a gap H2 is left between the other end of the outer sleeve two and the other end face of the inner ring of the first ball bearing. After the main bolt is tightened for pre-compression, both the gap H1 and the gap H2 are zero. By designing the values of the gap H1 and the gap H2, the pre-compression amount of the rubber bodies in the second rubber assembly and the first rubber assembly is controlled.

[0011] Preferably, the optimization method of the turboprop engine vibration damping system further includes optimizing the rigid limiting structure of the rubber assembly in the rear shock absorber, that is: the mounting frame assembly includes a mounting frame body, and a first ball bearing mounting hole is provided at one end of the mounting frame body. The main support assembly includes a main support frame body, and a through hole three is provided at the middle position of the main support frame body. After one end of the mounting frame assembly is inserted into one side of the main support assembly, the central axis of the first ball bearing mounting hole coincides with the central axis of the through hole three. After installation, the first ball bearing is arranged between the rod body of the main bolt and the first ball bearing mounting hole, so that the main bolt passing through the main support assembly is cooperatively connected with one end of the mounting frame assembly through the first ball bearing. Both the outer sleeve one and the outer sleeve two are located in the through hole three, and a gap H4 is left between the outer peripheral surface of the outer sleeve one and the inner peripheral surface of the through hole three, and a gap H5 is left between the outer peripheral surface of the outer sleeve two and the inner peripheral surface of the through hole three. When subjected to excessive impact force or vibration, a rigid limiting structure is formed by the contact between the outer peripheral surfaces of the outer sleeve one and the outer sleeve two and the inner peripheral surface of the through hole three.

[0012] Preferably, the turboprop engine layout method further includes optimizing the installation method between the rear shock absorber and the aircraft frame, that is: a second ball bearing mounting hole and a third ball bearing mounting hole are provided on the main support assembly. The ball bearing in the first screw rod with a ball bearing is the second ball bearing, and the ball bearing in the second screw rod with a ball bearing is the third ball bearing. After installation, the second ball bearing is arranged at the position between one end of the first screw rod and the second ball bearing mounting hole, so that one end of the first screw rod is cooperatively connected with the main bracket assembly through the second ball bearing. The third ball bearing is arranged at the position between one end of the second screw rod and the third ball bearing mounting hole, so that one end of the second screw rod is cooperatively connected with the main bracket assembly through the third ball bearing. The other ends of the first screw rod and the second screw rod are both connected to the aircraft frame.

[0013] Preferably, an installation arm one and an installation arm two are arranged on the aircraft frame. An installation through hole one is arranged at one end of the installation arm one, and an installation through hole two is arranged at one end of the installation arm two. During connection, the other end of the first screw rod passes through the installation through hole one and is locked with the first installation nut, and the other end of the second screw rod passes through the installation through hole two and is locked with the second installation nut, so that the other ends of the first screw rod and the second screw rod are both connected to the aircraft frame.

[0014] Preferably, the main bracket assembly further includes a rotating arm. A connecting arm and a hanging ear are arranged on one side of the main bracket frame body. The connecting arm and the hanging ear are of an integral structure with the main bracket frame body. One end of the rotating arm is hinged with the hanging ear. The second ball bearing mounting hole is arranged on the connecting arm, and the third ball bearing mounting hole is arranged at the other end of the rotating arm. During connection, first connect the first screw rod with the ball bearing to the installation arm one. After connection, adjust the installation position of the second screw rod with the ball bearing according to the actual position of the installation through hole two, and then connect the second screw rod with the ball bearing to the installation arm two.

[0015] Preferably, the arrangement method of the turboprop engine includes optimizing the hydraulic anti-torsion device of the engine vibration damping system, that is, the hydraulic anti-torsion device of the engine vibration damping system includes: an actuator, a connecting pipe and an accumulator; the actuator includes a first actuator and a second actuator, and the actuator has an actuator rod; the oil storage ends of the first actuator and the second actuator are in different up-and-down positions, the oil storage ends of the first actuator and the second actuator are connected through the connecting pipe, and the accumulator is connected to the connecting pipe; the actuator rod includes a first actuator rod and a second actuator rod, both of which are connected to the engine. The first actuator rod is arranged in the first actuator; the second actuator rod is arranged in the second actuator. The optimization of the hydraulic anti-torsion device of the engine vibration damping system is to design the actuator into a piston seal ring, a hydraulic cavity and a radial support part; the piston seal ring is an annular structure in contact with the inner wall of the hydraulic cavity and is arranged on the actuator rod; the actuator rod extends upward to the outside of the hydraulic cavity; the radial support part provides radial support for the actuator rod when the actuator rod moves.

[0016] Preferably, the accumulator comprises an energy storage chamber, a spring, an indicating rod and an accumulator piston; the energy storage chamber has a storage end and a pressure end, and the storage end is connected to a hydraulic system connecting pipe; the indicating rod and the spring are arranged at the pressure end, the indicating rod is connected to the accumulator piston and moves along with the accumulator piston, and the pressure of the hydraulic system can be detected by detecting the position of the indicating rod; the spring is sleeved on the indicating rod and presses the accumulator piston to compensate for the pressure of the hydraulic system.

[0017] The present invention also discloses a vibration damping system, which comprises: two front-side vibration dampers and a front-upper vibration damper installed between an aircraft frame and a turboprop engine at a position close to the front side of the engine; two rear-side vibration dampers installed between the aircraft frame and the turboprop engine at a position close to the rear side of the engine; a torque compensation device is further arranged on the aircraft frame at the front side of the engine, and the torque compensation device is connected to the two front-side vibration dampers; the two front-side vibration dampers and the two rear-side vibration dampers are respectively located on both sides of the turboprop engine, the front-upper vibration damper is located at the top of the turboprop engine, the rear-side vibration damper comprises a rubber component and a main support component, the rubber component comprises a rubber component one and a rubber component two, the main support component is arranged between the rubber component one and the rubber component two, during installation, a main bolt sequentially passes through the middle position of the rubber component two, the main support component and the middle position of the rubber component one and then is locked with a nut, so that the rubber component two and the rubber component one are pressed on the bottom surface and the top surface of the main support component, and the rubber bodies in the rubber component two and the rubber component one are in a pre-compressed state.

[0018] The beneficial effects of the present invention are as follows: By optimizing the connection method between the rear shock absorber, the front shock absorber and the torque compensation device and the torque compensation device, the present invention further optimizes the various performances of the product, improves its practicability in propeller aircraft, and makes it have a better application prospect. The connection position of the main bolt is set between the two rubber stacks of the second rubber component and the first rubber component. In this way, as long as a main bolt is used to press the second rubber component and the first rubber component against the bottom surface and the top surface of the main bracket component, the rubber bodies in the second rubber component and the first rubber component can be pre-compressed. Thus, compared with the prior art, the connection structure of one connecting bolt is reduced, the pre-compression structure of the rubber component is simplified, the installation steps are simplified, and the weight of the entire rear shock absorber device is reduced, meeting the requirements of lightweight design. In addition, with such a setting, the area of the third metal skeleton in the prior art is also reduced, further reducing the weight of the entire rear shock absorber device. By designing the values of the clearance H1 and the clearance H2, the pre-compression amount of the rubber bodies in the second rubber component and the first rubber component can be precisely controlled. After the bolt and nut reach the designed tightening torque, the sleeve generates metal rigid limit to ensure the designed compression state of the rubber, ensuring that the rubber parts do not loosen under the engine load condition of the rear shock absorber. When subjected to excessive impact or vibration, a rigid limit structure is formed by the contact between the outer peripheral surface of the first sleeve and the outer peripheral surface of the second sleeve and the inner peripheral surface of the third through hole, so that the present invention can limit the deformation degree of the shock absorber when subjected to excessive impact or vibration, thereby protecting the shock absorber and the engine from damage, ensuring that the shock absorber operates within a predetermined stroke range, and avoiding failures or damages caused by exceeding the design range. By optimizing the connection method, the present invention can realize the connection function between the front shock absorber and the torque compensation device. Thus, when the load changes, the torque compensator can automatically adjust the output torque to keep the engine running smoothly, reduce the vibration and noise levels, and thus improve the flight safety and comfort. By designing the nut as an elastic nut, which is elastically supported on the inner peripheral surface of the first through hole, and then using the first through hole to limit the rotation of the elastic nut, in fact, the elastic nut can only move axially in the first through hole and cannot rotate. During operation, the elastic nut is moved to the position of the inserted bolt rod part, and then the rotating bolt and the rotation-limited elastic nut are used in cooperation to lock, so that the bolt can be locked conveniently and quickly in a narrow installation space, reducing the working intensity and improving the working efficiency. By setting the positioning disc and the positioning through hole to form a positioning structure, the working intensity can be further reduced and the working efficiency can be improved. By optimizing the torque compensation device, it can limit the reaction torque generated by the engine propeller, and also has a radial support part to radially support the actuating rod, and the radial support part cooperates with the first limiting hole to provide radial support for the actuating rod. The radial support part can specifically be a support structure on the actuating rod or a support ring arranged on the hydraulic chamber.It can prevent the hydraulic oil leakage caused by the offset of the actuator rod of the hydraulic device due to the radial force of the engine, resulting in a gap between the piston sealing ring and the cylinder wall. Brief Description of the Drawings

[0019] Figure 1 It is a three-dimensional structural schematic diagram of the engine installed on the aircraft frame through the vibration damping system in the embodiment of the present invention; Figure 2 It is the pre-compression method of the rear shock absorber in the prior art; Figure 3 It is a three-dimensional structural schematic diagram of the rear shock absorber in the embodiment of the present invention; Figure 4 It is an exploded decomposition structural schematic diagram of the rear shock absorber in the embodiment of the present invention; Figure 5 It is an axial sectional structural schematic diagram of the rear shock absorber in the embodiment of the present invention; Figure 6 It is a three-dimensional structural schematic of Rubber Component 1 in the embodiment of the present invention Figure 1 ; Figure 7 It is a top view structural schematic diagram of the rear shock absorber in the embodiment of the present invention; Figure 8 It is a three-dimensional structural schematic diagram of the main support assembly in the embodiment of the present invention; Figure 9 It is a three-dimensional structural schematic of Rubber Component 1 in the embodiment of the present invention Figure 2 ; Figure 10 It is a three-dimensional structural schematic diagram of the mounting bracket assembly in the embodiment of the present invention; Figure 11 It is Figure 5 a partial axial sectional structural schematic diagram at the main bolt in; Figure 12 It is Figure 11 an enlarged structural schematic diagram of Part A in; Figure 13 It is Figure 11 an enlarged structural schematic diagram of Part B in; Figure 14 It is a three-dimensional structural schematic diagram when the main support assembly in the embodiment of the present invention is installed and connected to the aircraft frame; Figure 15 It is a partial three-dimensional structural schematic diagram when the front shock absorber in the embodiment of the present invention is connected to the torque compensation device; Figure 16 It is a partial sectional structural schematic diagram of the main mounting bracket of the front shock absorber in the embodiment of the present invention; Figure 17 It is a partial sectional structural schematic diagram when the front shock absorber in the embodiment of the present invention is connected to the torque compensation device; Figure 18 Schematic diagram of a partial cross-section before inserting a nut into through-hole 1 during connection in an embodiment of the present invention; Figure 19 Schematic diagram of a partial cross-section after inserting a nut into through-hole 1 during connection in an embodiment of the present invention; Figure 20 Schematic diagram of the three-dimensional structure of the elastic nut in an embodiment of the present invention; Figure 21 Schematic diagram of the three-dimensional structure of the right elastic part in an embodiment of the present invention; Figure 22 Schematic diagram of the front view structure of the right elastic part in an embodiment of the present invention; Figure 23 Schematic diagram of the axial cross-section structure of the left nut part in an embodiment of the present invention; Figure 24 Schematic diagram of the three-dimensional structure of the left nut part in an embodiment of the present invention; Figure 25 Schematic diagram of the axial cross-section structure of the nut sleeve of the left nut part in an embodiment of the present invention; Figure 26 Schematic diagram of the exploded three-dimensional structure of the left nut part in an embodiment of the present invention; Figure 27 Schematic diagram of the hydraulic torsion resistance device principle of the hydraulic torsion resistance device of the engine vibration damping system in an embodiment of the present invention; Figure 28 Schematic diagram of the three-dimensional structure of the hydraulic torsion resistance device of the engine vibration damping system in an embodiment of the present invention; In the figure: 1. Engine, 2. Aircraft frame, 211. First mounting arm, 212. Second mounting arm, 3. Front shock absorber, 4. Front upper shock absorber, 5. Rear shock absorber, 6. Torque compensation device, 7. Third connecting bolt, 8. Fourth connecting bolt, 9. Third metal skeleton, 10. Rubber body, 11. First rubber component, 12. Second rubber component, 13. Main support component, 131. Main support frame, 132. First through hole, 133. Second through hole, 134. Third through hole, 135. Second ball bearing mounting hole, 136. Third ball bearing mounting hole, 137. Rotating arm, 138. Connecting arm, 139. Hanging ear, 14. Mounting frame component, 141. Mounting frame, 142. First ball bearing mounting hole, 15. Main bolt, 16. Main nut, 17. First ball bearing, 171. Inner ring, 18. First screw rod, 19. Second screw rod, 20. Top plate, 201. Counterbore, 21. First bottom plate, 22. Second bottom plate, 23. First rubber stack, 24. Second rubber stack, 25. Through hole, 26. First positioning protrusion, 27. Second positioning protrusion, 28. Screw, 29. Second ball bearing, 30. Third ball bearing, 31. First bushing, 32. Second bushing, 33. Flange, 34. First mounting nut, 35. Second mounting nut, 36. Connecting pin shaft, 37. Main mounting bracket, 38. First main mounting bracket through hole, 39. Second main mounting bracket through hole, 40. Third main mounting bracket through hole, 41. Fourth ball bearing, 42. Connecting rod, 43. Bolt, 431. Bolt rod part, 44. Nut, 45. Left nut part, 46. Right elastic part, 461. Elastic sheet body, 4611. Elastic sheet body cavity, 462. Upper card, 463. Lower card, 47. Nut seat, 471. Seat body, 472. Seat body top plate, 473. Seat body bottom plate, 474. Seat body cavity, 48. Nut sleeve, 481. Sleeve body, 482. Sleeve body flange, 483. Sleeve body cavity, 49. Thread, 50. Inner conical surface, 51. First stop bar, 52. Second stop bar, 53. First stop bar mounting hole, 54. Sleeve body mounting space, 55. Positioning disc, 56. Connecting piece, 57. Positioning through hole, 58. Actuator, 59. Connecting pipe, 60. Accumulator, 601. Accumulation cavity, 602. Spring, 603. Indicator rod, 604. Accumulator piston, 605. Accumulator through hole, 61. Actuating rod, 62. Oil storage end, 63. Piston seal ring, 64. Hydraulic cavity, 65. Radial support part, 66. First limiting hole, 67. Second limiting hole, 68. Connecting hole, 69. Throttle hole. Detailed implementation mode

[0020] The technical solution of the present invention will be further elaborated in detail below in conjunction with the accompanying drawings and specific embodiments.

[0021] Embodiment: As Figure 1As shown, along the length of the turboprop engine 1, the side close to the turboprop is set as the front side of the engine, and the opposite side is the rear side of the engine. A method for arranging a turboprop engine is arranged on an aircraft frame through a vibration reduction system, and the vibration reduction system includes: two front shock absorbers 3 and a front upper shock absorber 4 installed between the aircraft frame 2 and the turboprop engine 1 near the front side of the engine; two rear shock absorbers 5 installed between the aircraft frame 2 and the turboprop engine 1 near the rear side of the engine; a torque compensation device 6 is also provided on the aircraft frame 2 at the front side of the engine, and the torque compensation device 6 is connected to the two front shock absorbers 3; the two front shock absorbers 3 and the two rear shock absorbers 5 are respectively located on both sides of the turboprop engine 1, and the front upper shock absorber 4 is located at the top of the turboprop engine 1. The turboprop engine 1 is connected to the aircraft frame 2 through the above-mentioned shock absorbers.

[0022] 1. In this embodiment, the rear shock absorber is first optimized: It can be seen from the patent documents cited in the background technology that a rubber pile is provided in the existing rear shock absorber, such as the third rubber pile in the patent document. After the rear shock absorber is installed, the third rubber pile is in a pre-compression state. In order to achieve the pre-compression state, in the prior art, pre-compression is performed by two connecting bolts, such as the third connecting bolt and the fourth connecting bolt in the patent document. However, the use of two connecting bolts to pre-compress the rubber pile has problems such as complex structure and cumbersome installation steps; in addition, the use of two connecting bolts to pre-compress the rubber pile also increases the weight of the entire rear shock absorber. In the application scenario of aircraft engines, an overly heavy rear shock absorber is extremely detrimental to the flight of the aircraft.

[0023] The applicant found through further research that in the patent documents of the prior art mentioned in the background technology, such as Figure 2 As shown, the third metal skeleton 9 on both sides of the rubber pile is clamped by the third connecting bolt 43 and the fourth connecting bolt 8, so as to pre-compress the two rubber bodies 10 in the rubber pile. After further studying the position distribution relationship between the third rubber pile and the two connecting bolts, the applicant found that the third connecting bolt 43 and the fourth connecting bolt 8 are respectively located on both sides of the two rubber bodies 10. In this position distribution relationship, if any one of the connecting bolts is reduced, the rubber body 10 will be compressed on one side and the other side will be in a loose state where it cannot be pressed tightly. Therefore, in this position distribution relationship, two connecting bolts must be used to pre-compress the rubber body. As a result, the above-mentioned problems such as complex structure, cumbersome installation steps, and increased weight of the entire rear shock absorbing device are caused.

[0024] To this end, the applicant has optimized: like Figures 3 to 5As shown in the figure, the rear shock absorber in this embodiment includes a first rubber component 11, a second rubber component 12, a main bracket component 13 disposed between the first rubber component 11 and the second rubber component 12, and a mounting bracket component 14 disposed on one side of the main bracket component 13. One end of the mounting bracket component 14 is inserted into the main bracket component 13. The main bolt 15 sequentially passes through the second rubber component 12, the main bracket component 13, and the first rubber component 11 and then is locked with the main nut 16, so as to press the second rubber component 12 and the first rubber component 11 against the bottom surface and the top surface of the main bracket component 13, making the rubber bodies in the second rubber component 12 and the first rubber component 11 in a pre-compressed state. The main bolt 15 passing through the main bracket component 13 is connected to one end of the mounting bracket component 14 through a first ball bearing 17. The other end of the mounting bracket component 14 is connected to a turboprop engine (not shown in the figure), and the other side of the main bracket component 13 is connected to an aircraft frame (not shown in the figure) through a first screw rod 18 with a ball bearing and a second screw rod 19 with a ball bearing. By installing the above-mentioned rear shock absorber between the turboprop engine and the aircraft frame, vibration energy can be absorbed and isolated, the service life of the turboprop engine can be prolonged, and the safety of the aircraft body can be ensured.

[0025] The structures of the second rubber component 12 and the first rubber component 11 are the same. Taking the first rubber component 11 as an example, as Figure 6 shown, the first rubber component 11 includes a top plate 20, a first bottom plate 21, and a second bottom plate 22. The rubber body includes a first rubber stack 23 and a second rubber stack 24. The first bottom plate 21 is vulcanized and bonded to the top plate 20 through the first rubber stack 23, and the second bottom plate 22 is vulcanized and bonded to the top plate 20 through the second rubber stack 24. The first rubber stack 23 and the second rubber stack 24 are respectively located at both ends of the top plate 20, and a through hole 25 is formed in the middle position of the top plate 20. When installed, the main bolt 15 sequentially passes through the through hole 25 of the second rubber component 12, the main bracket component 13, and the through hole 25 of the first rubber component 11 and then is locked with the main nut 16. After locking, the first bottom plate 21 and the second bottom plate 22 of the second rubber component 12 are in contact with the bottom surface of the main bracket component 13, and the first bottom plate 21 and the second bottom plate 22 of the first rubber component 11 are in contact with the top surface of the main bracket component 13. As Figure 7As shown, it can be seen that in this embodiment, the connection position of the main bolt 15 is set at the position between the two rubber piles of the second rubber component 12 and the first rubber component 11. In this way, as long as a main bolt 15 is used to press the second rubber component 12 and the first rubber component 11 against the bottom surface and the top surface of the main bracket assembly 13, the rubber bodies in the second rubber component 12 and the first rubber component 11 can be pre-compressed. Thus, compared with the prior art, the connection structure of one connecting bolt is reduced, the pre-compression structure of the rubber component is simplified, the installation steps are simplified, and the weight of the entire rear shock absorber is reduced, meeting the requirements of lightweight design. In addition, with this setting, the area of the third metal skeleton (i.e., the top plate in this embodiment) in the prior art is also reduced, further reducing the weight of the entire rear shock absorber.

[0026] As Figure 8 and Figure 9 shown, the main bracket assembly 13 includes a main bracket frame 131. A first through hole 132 and a second through hole 133 are formed in the main bracket frame 131. Positioning protrusions 26 and 27 are respectively arranged on the bottom plates 21 and 22 of the second rubber component 12 and the first rubber component 11. The shapes of the positioning protrusions 26 and 27 match those of the first through hole 132 and the second through hole 133. When the second rubber component 12 and the first rubber component 11 are pressed against the bottom surface and the top surface of the main bracket assembly 13, the positioning protrusions 26 and 27 of the first rubber component 11 are respectively inserted into one end of the first through hole 132 and one end of the second through hole 133 on the main bracket frame 131, and the positioning protrusions 26 and 27 of the second rubber component 12 are respectively inserted into the other end of the first through hole 132 and the other end of the second through hole 133 on the main bracket frame 131, so as to position the positions of the second rubber component 12 and the first rubber component 11 when they are pressed against the bottom surface and the top surface of the main bracket assembly 13. In this way, the assembly accuracy and assembly speed of the rear shock absorber can be further improved; in addition, the weight of the main bracket frame can also be reduced through the formed first through hole and second through hole, further meeting the requirements of lightweight design.

[0027] As Figure 8 and Figure 10 shown, the mounting bracket assembly 14 includes a mounting bracket frame 141. A first ball bearing mounting hole 142 is arranged at one end of the mounting bracket frame 141. A third through hole 134 is also formed in the main bracket frame 131 at the position between the first through hole 132 and the second through hole 133; As Figure 5As shown, after one end of the mounting frame assembly 14 is inserted into one side of the main support assembly 13, the central axis of the first ball bearing mounting hole 142 coincides with the central axis of the third through hole 134; after installation, the first ball bearing 17 is disposed at a position between the outer rod body of the main bolt 15 and the first ball bearing mounting hole 142, so that the main bolt 15 passing through the main support assembly 13 is connected to one end of the mounting frame assembly 14 through the first ball bearing 17. As Figure 10 shown, the other end of the mounting frame body 141 is connected to a turboprop engine (not shown in the figure) by screws 28.

[0028] As Figure 8 shown, a second ball bearing mounting hole 135 and a third ball bearing mounting hole 136 are provided at the other side of the main support assembly 13. The ball bearing in the first screw with ball bearing 18 is the second ball bearing 29, and the ball bearing in the second screw with ball bearing 19 is the third ball bearing 30; after installation, the second ball bearing 29 is disposed at a position between one end of the first screw 18 and the second ball bearing mounting hole 135, so that one end of the first screw 18 is connected to the other side of the main support assembly 13 through the second ball bearing 29. The third ball bearing 30 is disposed at a position between one end of the second screw 19 and the third ball bearing mounting hole 136, so that one end of the second screw 19 is connected to the other side of the main support assembly 13 through the third ball bearing 30. The other ends of the first screw 18 and the second screw 19 are both connected to an aircraft frame (not shown in the figure). Thus, through the above structure, the other side of the main support assembly 13 is connected to the aircraft frame (not shown in the figure) through the first screw with ball bearing 18 and the second screw with ball bearing 19.

[0029] In this embodiment, the main support assembly is connected to the aircraft frame by designing the first screw with ball bearing and the second screw with ball bearing, so that the rear shock absorber can obtain more mounting redundancy in all directions, can compensate for the mounting clearance, and improves the safety, reliability and convenience of the installation and use of the rear shock absorber.

[0030] In order to further accurately control the pre-compression amount of the rubber bodies in the second rubber component and the first rubber component, the applicant has made further improvements, such as Figure 11 and Figure 12As shown, a first sleeve 31 and a second sleeve 32 are also sleeved outside the main bolt 15; the first sleeve 31 is located between the top plate 20 of the first rubber component 11 and the first ball bearing 17, and the second sleeve 32 is located between the top plate 20 of the second rubber component 12 and the first ball bearing 17. Before pre-compression, one end of the first sleeve 31 contacts the top plate 20 of the first rubber component 11, and there is a gap H1 between the other end of the first sleeve 31 and one end face of the inner ring 171 of the first ball bearing 17. One end of the second sleeve 32 contacts the top plate 20 of the second rubber component 12, and there is a gap H2 between the other end of the second sleeve 32 and the other end face of the inner ring 171 of the first ball bearing 17. After the main bolt 15 is tightened for pre-compression, both the gap H1 and the gap H2 are zero, that is, the other end of the first sleeve 31 contacts one end face of the inner ring 171 of the first ball bearing 17, and the other end of the second sleeve 32 contacts the other end face of the inner ring 171 of the first ball bearing 17. In this way, by using the rigid limit between the sleeve and the ball bearing, the pre-compression amount of the rubber bodies in the second rubber component and the first rubber component can be precisely controlled by designing the values of the gaps H1 and H2. After the bolt and nut reach the designed tightening torque, the sleeve generates metal rigid limit to ensure the designed compression state of the rubber, ensuring that the rubber parts do not loosen under the engine load condition of the rear shock absorber. In addition, it should be noted that after pre-compression, the first sleeve and the second sleeve can also be used to axially limit the ball bearing.

[0031] As Figure 13 shown, flanges 33 are provided on the outer peripheral surfaces of one end portions of the first sleeve 31 and the second sleeve 32, and counterbores 201 are provided on the top plates 20 of the first rubber component 11 and the second rubber component 12. When one end of the first sleeve 31 and the second sleeve 32 contacts the top plate 20, the end portions of one ends of the first sleeve 31 and the second sleeve 32 are respectively inserted into the counterbores 201 on the top plates 20 of the first rubber component 11 and the second rubber component 12, and the flanges 33 on the end portions of one ends of the first sleeve 31 and the second sleeve 32 respectively contact the top plates 20 of the first rubber component 11 and the second rubber component 12. At this time, there are gaps H3 between the end portions of one ends of the first sleeve 31 and the second sleeve 32 and the bottom surfaces of the counterbores 201 on the top plates 20 of the first rubber component 11 and the second rubber component 12.

[0032] As Figure 4 、 Figure 8 and Figure 14As shown, when connecting to the aircraft frame in this embodiment, mounting arm one 211 and mounting arm two 212 are provided on the aircraft frame 2. A mounting through-hole one (not shown in the figure) is provided at one end of the mounting arm one 211, and a mounting through-hole two (not shown in the figure) is provided at one end of the mounting arm two 212. When connecting, the other end of the screw one 18 is passed through the mounting through-hole one and then locked with the mounting nut one 34, and the other end of the screw two 19 is passed through the mounting through-hole two and then locked with the mounting nut two 35, so that the other ends of the screw one 18 and the screw two 19 are both connected to the aircraft frame 2.

[0033] The main support assembly 13 further includes a rotating arm 137. A connecting arm 138 and a hanging ear 139 are provided on one side of the main support frame body 131. The connecting arm 138 and the hanging ear 139 are of an integral structure with the main support frame body 131. One end of the rotating arm 137 is hinged to the hanging ear 139 through a connecting pin shaft 36. The ball bearing two mounting hole 135 is provided on the connecting arm 138, and the ball bearing three mounting hole 136 is provided at the other end of the rotating arm 137. Due to the influence of various factors, the relative positions between the mounting through-hole one and the mounting through-hole two on the aircraft frame 2 are not determined. Therefore, during connection in the prior art, the situation of difficult installation often occurs. When installing in this embodiment, first connect the screw one 18 with a ball bearing to the mounting arm one. After connection, due to the hinged structure between the rotating arm 137 and the hanging ear 139, the installation position of the screw two 19 with a ball bearing can be adjusted according to the actual position of the mounting through-hole two, so that the screw two 19 with a ball bearing can be conveniently connected to the mounting arm two, thereby further improving the convenience of installation and use of the rear shock absorber. In addition, the connecting arm 138 and the main support frame body 131 are designed as an integral structure. In this way, compared with the prior art, one hinge point is reduced, so that the rear shock absorber is more stable during the shock absorption work.

[0034] As Figure 11 and Figure 12 As shown, both the sleeve one 31 and the sleeve two 32 are located in the through-hole three 134, and a gap H4 is left between the outer peripheral surface of the sleeve one 31 and the inner peripheral surface of the through-hole three 134, and a gap H5 is left between the outer peripheral surface of the sleeve two 32 and the inner peripheral surface of the through-hole three 134. When subjected to excessive impact force or vibration, a rigid limiting structure is formed by the contact between the outer peripheral surfaces of the sleeve one 31 and the sleeve two 32 and the inner peripheral surface of the through-hole three 134, so that this embodiment can limit the deformation degree of the shock absorber when subjected to excessive impact force or vibration, thereby protecting the shock absorber and the engine from damage, ensuring that the shock absorber works within a predetermined stroke range, and avoiding faults or damages caused by exceeding the design range.

[0035] II. In this embodiment, the connection method between the front shock absorber and the torque compensation device is optimized as follows: During the operation of a turboprop engine, it may be affected by various load changes, such as changes in flight speed, altitude, propeller speed, etc. These changes may cause fluctuations in the torque generated by the engine. Therefore, a hydraulic torque compensation device is generally installed on the aircraft frame, and the torque compensator is mainly used to reduce the torque fluctuations caused by load changes. During operation, the hydraulic torque compensation device generally needs to be connected to the front shock absorber to achieve its function of automatically adjusting the output torque.

[0036] In the patent documents cited in the background art, there is no detailed disclosure of how the hydraulic torque compensation device is connected to the front shock absorber.

[0037] Therefore, the applicant has made optimizations: As Figure 15 and Figure 16 shown, the front shock absorber 3 includes a main mounting bracket 37. A vertical main mounting bracket through-hole one 38 and a horizontal main mounting bracket through-hole two 39 are formed in the main mounting bracket 37. The central axes of the main mounting bracket through-hole one 38 and the main mounting bracket through-hole two 39 are cross-distributed, and one end of the main mounting bracket through-hole two 39 is communicated with the main mounting bracket through-hole one 38. A vertical main mounting bracket through-hole three 40 is also formed in the main mounting bracket 37. The main mounting bracket through-hole three 40 is located at the middle position of the main mounting bracket through-hole two 39, and one end of the main mounting bracket through-hole three 40 is communicated with the main mounting bracket through-hole two 39. As Figure 15 and Figure 17 shown, when connecting the front shock absorber and the torque compensation device, one end of the connecting rod 42 with a ball bearing four 41 is inserted into the main mounting bracket through-hole two 39 from the main mounting bracket through-hole three 40. The other end of the connecting rod 42 is connected to the torque compensation device. Then, the bolt rod part 431 of the bolt 43 is inserted into the main mounting bracket through-hole two 39, passes through the inner ring of the ball bearing four 41 at one end of the connecting rod 42 and is in mating connection with the inner ring of the ball bearing four 41 and then extends into the main mounting bracket through-hole one 38. Then, a nut 44 is locked on the bolt rod part 431 located in the main mounting bracket through-hole one 38 in the main mounting bracket through-hole one 38, so that the bolt 43 is locked on the main mounting bracket 37, connecting the front shock absorber and the torque compensation device. Through the above connection method, the connection function between the front shock absorber and the torque compensation device can be realized in this embodiment. Thus, when the load changes, the torque compensator can automatically adjust the output torque, maintain the stable operation of the engine, reduce the vibration and noise levels, and improve the flight safety and comfort.

[0038] Another problem that exists during connection is that if you want to lock the bolt 43, you must fix the nut 44, apply torque to the bolt 43, or fix the bolt 43 and apply torque to the nut 44. However, due to certain reasons, the space of the through hole 38 of the main mounting bracket is extremely narrow, and the operator cannot insert his hand or a wrench into it to fix the nut 44 or apply torque to the nut 44. Therefore, in this installation condition, it is very difficult to lock the bolt, which increases the working intensity and reduces the working efficiency. Therefore, in this embodiment, the applicant designs the nut 44 as an elastic nut 44, and the shape of the elastic nut 44 matches the shape of the through hole 38 of the main mounting bracket; as Figures 17 to 19 shown, during connection, first insert the elastic nut 44 into the through hole 38 of the main mounting bracket from one end of the through hole 38 of the main mounting bracket. When the elastic nut 44 enters the through hole 38 of the main mounting bracket, due to the elastic action of the elastic nut 44, the elastic nut 44 is supported in the through hole 38 of the main mounting bracket and will not fall out. Then, use a tool such as a rod to push the elastic nut 44 to move axially in the through hole 38 of the main mounting bracket until it moves to one end port of the through hole 39 of the main mounting bracket. Then, insert the bolt 43 into the through hole 39 of the main mounting bracket so that the bolt rod portion 431 is located at the elastic nut 44, and then apply torque to the bolt 43. At this time, since the shape of the elastic nut 44 matches the shape of the through hole 38 of the main mounting bracket, the through hole 38 of the main mounting bracket can be used to limit the rotation of the elastic nut 44, so that when the bolt 43 rotates, the elastic nut 44 is fixed and cannot rotate with the bolt 43. Finally, the bolt 43 is locked to the main mounting bracket through the elastic nut 44. In this embodiment, by designing an elastic nut, using its elasticity to support on the inner peripheral surface of the through hole 1, and then using the through hole 1 to limit the rotation of the elastic nut, in fact, the elastic nut can only move axially in the through hole 1 and cannot rotate. During work, the elastic nut is moved to the inserted bolt rod portion, and then the rotating bolt and the rotation-limited elastic nut are used in cooperation to lock, so that the bolt can be locked conveniently and quickly in a narrow installation space, reducing the working intensity and improving the working efficiency.

[0039] As Figure 20As shown, the elastic nut 44 is columnar, including a left nut portion 45 and a right elastic portion 46 connected to the left nut portion 45. The outer peripheral surface shape of the columnar elastic nut 44 matches the inner peripheral surface shape of the first through hole 38 of the main mounting bracket. In this embodiment, the inner peripheral surface of the first through hole 38 of the main mounting bracket is circular. Therefore, both the left nut portion 45 and the right elastic portion 46 are semi-circular. When the inner peripheral surface shape of the first through hole 38 of the main mounting bracket is square or other shapes, correspondingly, the outer peripheral surface shape of the elastic nut 44 is also set to square or other shapes. When the elastic nut 44 is placed into the first through hole 38 of the main mounting bracket, the outer peripheral surface of the right elastic portion 46 is squeezed by the inner peripheral surface of the first through hole 38 of the main mounting bracket and undergoes elastic deformation. After the elastic nut 44 is placed into the first through hole 38 of the main mounting bracket, the outer peripheral surface of the left nut portion 45 contacts the inner peripheral surface of the first through hole 38 of the main mounting bracket. Under the action of the restoring force of the elastic force, the outer peripheral surface of the right elastic portion 46 tightly adheres to and elastically contacts the inner peripheral surface of the first through hole 38 of the main mounting bracket, thereby supporting the elastic nut 44 on the inner peripheral surface of the first through hole 38 of the main mounting bracket and preventing it from falling out.

[0040] As Figure 21 and Figure 22 shown, the right elastic portion 46 includes a leaf spring body 461 and a leaf spring connecting member provided on the leaf spring body 461. The leaf spring body 461 is connected to the left nut portion 45 through the leaf spring connecting member. In this embodiment, the leaf spring connecting member is an upper card 462 provided at the top of the leaf spring body 461 and a lower card 463 provided at the bottom of the leaf spring body 461. When connecting the left nut portion 45, as Figure 20As shown, the left nut portion 45 is engaged between the upper card 462 and the lower card 463, thereby connecting the left nut portion 45 and the right elastic portion 46 into one body. By the above-mentioned engaging structure, the elastic sheet body and the elastic sheet connecting member are connected into one body, simplifying the assembly structure. The outer side surface of the elastic sheet body 461 is the outer peripheral surface of the right elastic portion 46. The shape of the outer side surface of the elastic sheet body 461 matches the shape of the inner peripheral surface of the first through hole 38 of the main mounting bracket. Since in this embodiment, the inner peripheral surface of the first through hole 38 of the main mounting bracket is circular, correspondingly, the outer side surface of the elastic sheet body 461 is set as an arc surface. Here, when the inner peripheral surface of the first through hole 38 of the main mounting bracket is square, the outer side surface of the elastic sheet body 461 can also be set as a square. In order to support the elastic nut 44 on the inner peripheral surface of the first through hole 38 of the main mounting bracket through the elastic deformation of the outer peripheral surface of the right elastic portion 46, the size of the elastic sheet body 461 is slightly larger than the size of the first through hole 38 of the main mounting bracket. In this embodiment, the radius of the elastic sheet body 461 is slightly larger than the radius of the first through hole 38 of the main mounting bracket, so that when the elastic nut 44 is placed into the first through hole 38 of the main mounting bracket, the elastic sheet body 461 can be squeezed and elastically deformed. After the elastic nut 44 is placed into the first through hole 38 of the main mounting bracket, under the action of the restoring force of the elastic force, the outer side surface of the elastic sheet body 461 elastically abuts against the inner peripheral surface of the first through hole 38 of the main mounting bracket, supporting the entire elastic nut 44 in the first through hole 38 of the main mounting bracket and preventing it from falling off. In addition, along the axial direction, an elastic deformation gap L1 is left between the elastic sheet body 461 and the left nut portion 45. In this way, when the outer side surface of the elastic sheet body 461 is squeezed and deformed by the first through hole 38 of the main mounting bracket, the elastic deformation gap L1 can ensure that the elastic sheet body 461 has sufficient deformation space when elastically deforming.

[0041] As Figure 23 and Figure 24As shown, the left nut portion 45 includes a hollow nut seat 47 and a nut sleeve 48 connected to one side of the nut seat 47. The elastic deformation gap L1 is provided at the position between the nut seat 47 and the elastic sheet body 461. The nut seat 47 includes a hollow seat body 471, a seat body top plate 472 provided on one side of the seat body 471, and a seat body bottom plate 473 provided on one side of the seat body 471. The other side surface of the seat body 471 is the outer side surface of the seat body 471, and the outer side surface of the seat body 471 is the outer peripheral surface of the left nut portion 45. The shape of the outer side surface of the seat body 471 matches the shape of the inner peripheral surface of the first through hole 38 of the main mounting bracket. Since in this embodiment, the inner peripheral surface of the first through hole 38 of the main mounting bracket is circular, correspondingly, the outer side surface of the seat body 471 is provided as an arc surface. Here, when the inner peripheral surface of the first through hole 38 of the main mounting bracket is square, the outer side surface of the seat body 471 can also be provided as a square. The size of the seat body 471 matches the size of the first through hole 38 of the main mounting bracket, so that when the elastic nut 44 is placed into the first through hole 38 of the main mounting bracket, the outer side surface of the seat body 471 contacts the inner peripheral surface of the first through hole 38 of the main mounting bracket. In addition, the matching of the shape of the outer side surface of the seat body 471 with the shape of the inner peripheral surface of the first through hole 38 of the main mounting bracket also forms a first rotational limiting structure for the left nut portion 45 between the seat body 471 and the first through hole 38 of the main mounting bracket, preventing the left nut portion 45 from rotating when tightening the bolt during work. When the left nut portion is connected to the right elastic portion, the left nut portion 45 is engaged between the upper card 462 and the lower card 463, so that the seat body top plate 472 of the left nut portion 45 contacts the upper card 462, and the seat body bottom plate 473 of the left nut portion 45 contacts the lower card 463, thereby connecting the left nut portion 45 and the right elastic portion 46 into one body.

[0042] As Figure 23 and Figure 25As shown, the nut sleeve 48 includes a sleeve body 481 and a sleeve flange 482 provided at one end of the sleeve body 481. The sleeve body 481 and the sleeve flange 482 are of an integral structure. A thread 49 is provided on the inner circumferential surface of the sleeve body 481. The inner cavity 483 of the sleeve body 481 communicates with the inner cavity 474 of the seat body 471 and the inner cavity 483 of the sleeve body and the inner cavity 474 of the seat body are located on the same central axis. During operation, the rod portion of the bolt extends into the inner cavity 474 of the seat body from the inner cavity 483 of the sleeve body. An inner conical surface 50 is further provided on the inner circumferential surface of the sleeve body 481 and near the side of the sleeve flange 482. When the rod portion 431 of the bolt extends in and there is some deviation between the central axis of the rod portion 431 of the bolt and the central axis of the sleeve body 481, during the process of the rod portion 431 of the bolt extending in, by using the contact and cooperation between the end portion of the rod portion 431 of the bolt and the inner conical surface 50, the position of the elastic nut can be automatically adjusted, so that the elastic nut moves axially by some positions for fine adjustment, making the central axis of the rod portion 431 of the bolt coincide with the central axis of the sleeve body 481, ensuring that the rod portion 431 of the bolt can smoothly enter the inner cavity of the sleeve body 481 and be in mating connection with the thread 49, thus ensuring the smooth progress of the work.

[0043] As Figure 24 and Figure 25As shown, for the convenience of connection between the nut seat 47 and the nut sleeve 48, the applicant has designed a simple connection method, that is, a first stop bar 51 and a second stop bar 52 are respectively provided on the seat top plate 472 and the seat bottom plate 473 of the nut seat 47. When connecting, first place the nut sleeve 48 on one side of the nut seat 47, and then connect the first stop bar 51 and the second stop bar 52 to the seat top plate 472 and the seat bottom plate 473 of the nut seat 47 respectively, so that one side of the sleeve flange 482 of the nut sleeve 48 is in contact with the seat body 471 of the nut seat 47, and the first stop bar 51 and the second stop bar 52 are in contact with the other side of the sleeve flange 482 of the nut sleeve 48. One function of the two stop bars is to connect the nut sleeve, and the other function is that during the working process, the bolt will generate an axial moving force on the nut sleeve. By using the first stop bar 51 and the second stop bar 52 to block in the axial moving direction of the nut sleeve, the problem of axial movement of the nut sleeve is avoided, ensuring the normal progress of the work. Here, in order to simplify the connection structure between the stop bar and the nut seat, in this embodiment, a first stop bar installation hole 53 and a second stop bar installation hole (not shown in the figure) are respectively opened on the seat top plate 472 and the seat bottom plate 473. When connecting, first use an elastic metal sheet (such as an iron sheet, a steel sheet, etc.) to roll into the first stop bar 51 and the second stop bar 52, and then insert one end of the rolled first stop bar 51 and one end of the second stop bar 52 into the first stop bar installation hole 53 and the second stop bar installation hole respectively. In this way, by using the elastic restoring force of the rolled elastic metal sheet, one end of the first stop bar 51 and one end of the second stop bar 52 are expanded and clamped in the first stop bar installation hole 53 and the second stop bar installation hole, greatly simplifying the connection structure.

[0044] As Figure 26 shown, the seat body 471, the seat top plate 472 and the seat bottom plate 473 enclose a sleeve installation space 54 on one side of the seat body 471. The outer peripheral surface shape of the sleeve flange 482 matches the shape of the sleeve installation space 54. When connecting, after the sleeve flange 482 is placed into the sleeve installation space 54, a second rotational limiting structure for the nut sleeve is formed by the cooperation of the sleeve flange 482 and the sleeve installation space 54. The outer peripheral surface shape of the sleeve flange 482 can be set as a polygon. In this embodiment, the outer peripheral surface shape of the sleeve flange 482 is set as a square. Therefore, the sleeve installation space 54 is also set as a square. Such a setting is mainly to prevent the nut sleeve 48 from rotating circumferentially during work, facilitating the tightening of the bolt. During work, the rotation of the nut sleeve is restricted by the second rotational limiting structure formed between the sleeve flange 482 and the sleeve installation space 54 in sequence, and the rotation of the left nut part is restricted by the first rotational limiting structure formed between the seat body and the first through hole, thus finally realizing the function of the first through hole 38 of the main installation bracket to limit the rotation of the elastic nut 44.

[0045] As Figure 20 andFigure 21 As shown, a cavity 4611 is formed in the elastic piece body 461. A positioning disc 55 is arranged in the cavity 4611 of the elastic piece body. The positioning disc 55 is connected to the elastic piece body 461 through a connecting piece 56, and the central axis of the positioning disc 55 coincides with the central axis of the inner cavity 483 of the nut sleeve 48. Here, the central axis of the positioning disc 55 and the central axis of the inner cavity 483 of the nut sleeve 48 may not coincide, mainly for positioning purposes. As Figures 16 to 19 As shown, a positioning through hole 57 is further arranged on the main mounting bracket 37 at a position corresponding to the second through hole 39 of the main mounting bracket. The positioning through hole 57 is communicated with the first through hole 38 of the main mounting bracket, and the central axis of the positioning through hole 57 coincides with the central axis of the second through hole 39 of the main mounting bracket. Here, the central axis of the positioning through hole 57 and the central axis of the second through hole 39 of the main mounting bracket may not coincide, mainly for positioning purposes. The shape of the positioning disc 55 on the elastic piece body 461 matches the shape of the positioning through hole 57.

[0046] During operation, when the elastic nut 44 moves downward in the first through hole 38 of the main mounting bracket, due to the narrow space, it is difficult to observe whether the elastic nut 44 has moved downward in place. Therefore, a positioning through hole 57 is arranged at a position opposite to the second through hole 39 of the main mounting bracket. During the downward movement of the elastic nut 44, when the positioning disc 55 on the elastic piece body 461 is caught in the positioning through hole 57, it means that the elastic nut 44 has moved downward in place. At this time, the inner cavity 483 of the nut sleeve 48, the inner cavity 474 of the seat body, and the second through hole 39 of the main mounting bracket are in the same central axis position. After the elastic nut 44 moves downward in place, the bolt rod part 431 of the bolt is inserted into the inner cavity 474 of the seat body and the inner cavity 483 of the nut sleeve 48 through the second through hole 39 of the main mounting bracket for assembly, which can further reduce the working intensity and improve the working efficiency.

[0047] III. In this embodiment, the torque compensation device is also optimized: The aircraft turboprop engine is installed on the engine mounting frame through the vibration isolation device. When the aircraft is running, the engine will generate torque. When the torque is too large, it may damage the vibration isolation device. In this case, it is necessary to provide a counter-torque to offset the torque generated by the engine. In order to resist torsion and reduce the impact on the vibration isolation device at the same time, a hydraulic torque compensation device is considered to be installed on the engine frame to limit the reaction torque generated by the engine propeller. However, the existing hydraulic torque compensation device can only resist its hydraulic axial torque, and when the engine generates a radial force, it is easy to cause the piston seal of the hydraulic device to be damaged, resulting in hydraulic oil leakage.

[0048] The Chinese invention patent with the application publication number CN104976278A and the application publication date of October 14, 2015 discloses a hydraulic torque compensation device, which includes an oil storage tank, a metal spring arranged inside the oil storage tank, a piston connected to the metal spring, a throttle valve and a relief valve integrated inside the oil storage tank, a short conduit and a long conduit connected to the oil storage tank, a left actuator connected to the other end of the short conduit, a right actuator connected to the long conduit, a first actuating rod arranged inside the left actuator, and a second actuating rod arranged inside the right actuator.

[0049] During the working process of the hydraulic torque compensation device in this patent document, when the engine generates a radial force, the first actuating rod and the second actuating rod in the hydraulic torque compensation device may both swing radially, which is likely to cause damage to the piston seal of the hydraulic device, resulting in hydraulic oil leakage.

[0050] Therefore, the applicant has made optimizations: As Figure 27 shown, a torque compensation device using hydraulic pressure in this embodiment includes: an actuator 58, a connecting pipe 59, and an accumulator 60; the actuator 58 includes a first actuator and a second actuator, and the actuator 58 has an actuating rod 61; the oil storage ends 62 of the first actuator and the second actuator are at different upper and lower positions, the oil storage ends 62 of the first actuator and the second actuator are connected by the connecting pipe 59, and the accumulator 60 is connected to the connecting pipe 59; the actuating rod 61 includes a first actuating rod and a second actuating rod, and both are respectively connected to the main mounting brackets 37 of two front shock absorbers through two connecting rods 42. The first actuating rod is arranged inside the first actuator; the second actuating rod is arranged inside the second actuator; the actuator 58 also has a piston seal ring 63, a hydraulic chamber 64, and a radial support portion 65; the piston seal ring 63 is an annular structure in contact with the inner wall of the hydraulic chamber 64 and is arranged on the actuating rod 61; the actuating rod 61 extends upward to the outside of the hydraulic chamber 64; the radial support portion 65 provides radial support for the actuating rod 61 when the actuating rod 61 moves.

[0051] It should be noted that with reference to Figure 27 and Figure 28, the hydraulic anti-torsion device of the engine 1 vibration damping system in the embodiment of the present application is fixedly installed on the aircraft frame, and axially resists torsion in one direction through the hydraulic anti-torsion device, while reducing the influence on the vibration isolation device during torsion resistance. The connecting pipe 59 is made of metal. Each actuator 58 has a liquid storage end and an air end; when the liquid storage end of the first actuator 58 is above, the liquid storage end of the second actuator 58 is below, and provides a counter-torque when the engine 1 twists. The actuator rod 61 extends upward to the outside of the hydraulic chamber 64. The actuator 58 of the hydraulic anti-torsion device also has a radial support portion 65. When the engine 1 generates a radial force, the radial support portion 65 supports and limits the upward extension end of the actuator rod 61, or supports and limits the upward extension end and the lower end of the actuator rod 61 to radially limit and support the entire actuator rod 61, preventing the piston seal ring from being twisted or offset due to the drive of the actuator rod 61, thereby causing damage to the hydraulic piston seal. In this embodiment and subsequent embodiments, the actuators 58 and the accumulators 60 are both provided with mounting holes and fixedly installed on the aircraft engine mounting bracket.

[0052] Specifically, referring to Figure 27 , when the engine 1 generates an input torque Tin, the piston seal ring 63 and the actuator rod 61 of the left actuator 58 move upward by XC, and at the same time, the piston seal ring 63 and the actuator rod 61 of the right actuator 58 move downward by XC.

[0053] In this embodiment, the hydraulic anti-torsion device of the engine 1 vibration damping system provides a counter-torque under the condition of large torque of the engine 1; it also has a radial support portion 65 to radially support the actuator rod 61, which can prevent the actuator rod 61 of the hydraulic device from shifting due to the radial force of the engine 1, and the piston seal ring and the inner wall of the hydraulic chamber 64 have a gap, resulting in hydraulic oil leakage.

[0054] Furthermore, a first limiting hole 66 is provided at the lower end of the hydraulic chamber 64, and the actuator rod 61 extends downward through the first limiting hole 66 to the outside of the hydraulic chamber 64; the radial support portion 65 is arranged on the hydraulic chamber 64 and / or the actuator rod 61. When the actuator rod 61 moves, the radial support portion 65 cooperates with the first limiting hole 66 to provide radial support for the actuator rod 61.

[0055] It should be noted that the first limiting hole 66 axially limits and supports the actuator rod 61. The radial support portion 65 can be: when the actuator rod 61 extends upward, a support structure is provided above the hydraulic chamber 64, and the support structure cooperates with the first limiting hole 66 to provide radial constraint and support for the upward extending actuator rod 61; when the actuator rod 61 extends upward, support structures are provided above and below the actuator cylinder to radially constrain the actuator rod 61. The support structure can specifically be a support ring or a support rod, etc., arranged on the actuator rod 61 and / or the body of the hydraulic chamber 64.

[0056] In this embodiment, the high-pressure piston dynamic sealing structure has a first limiting hole 66 for axially limiting and axially supporting the actuating rod 61, and also has a radial supporting portion 65 cooperating with the first limiting hole 66 to provide radial support for the actuating rod 61. The radial supporting portion 65 can specifically be a supporting structure on the actuating rod 61 or a supporting ring provided on the hydraulic chamber 64. It can prevent the offset of the actuating rod 61 of the hydraulic device caused by the radial force of the engine 1, and the leakage of hydraulic oil caused by the gap between the piston sealing ring and the inner wall of the hydraulic chamber 64.

[0057] Further, the radial supporting portion 65 is: cavities are provided at both the upper and lower ends of the hydraulic chamber 64, and an annular supporting structure is fixedly arranged on the actuating rod 61, and the annular supporting structure can move within the cavities; baffles are provided at both the upper and lower ends of the hydraulic chamber 64, and an annular supporting structure is fixedly arranged on the actuating rod 61, and the baffles provide radial support for the annular supporting structure; a supporting ring is fixedly arranged at the upper end of the hydraulic chamber 64, and the supporting ring provides radial support for the actuating rod 61; or supporting rings are fixedly arranged at both the upper and lower ends of the hydraulic chamber 64, and the supporting rings provide radial support for the actuating rod 61.

[0058] It should be noted that when the actuating rod 61 moves up and down, the first limiting hole 66 axially limits the actuating rod 61. At this time, the actuating rod 61 is equivalent to having only one supporting point at the first limiting hole 66. Once the engine 1 generates a radial force, it is easy to cause the actuating rod 61 to twist or deviate from the central axis, resulting in the piston sealing ring deviating by a corresponding angle and no longer being perpendicular to the inner wall of the hydraulic chamber 64, thus forming a gap and causing hydraulic oil leakage. The radial supporting portion 65 is an additional supporting point added to the upward extending end of the hydraulic rod. This newly added supporting point cooperates with the supporting point at the first limiting hole 66 to provide radial support for the actuating rod 61. In other feasible embodiments, in addition to supporting the upward extending end of the hydraulic rod, the radial supporting portion 65 can also add a supporting point below the first limiting hole 66 to further provide radial support for the actuating rod 61. An upper supporting ring is provided at the upper end of the hydraulic chamber 64 to limit and support the upward extending end of the actuating rod 61, and a lower supporting ring is also provided below the first limiting hole 66 of the hydraulic chamber 64 to further limit and support the actuating rod 61.

[0059] Specifically, the annular supporting structure is fixedly arranged at the upward extending end and the lower end of the actuating rod 61. The upward extending end and the lower end remain outside the hydraulic chamber 64 during the movement of the actuating rod 61. The outer side of the annular supporting structure contacts the inner wall of the cavity or the baffle, and the cavity or the baffle limits the annular supporting structure. When the actuating rod 61 moves up and down, the first limiting hole 66 axially limits the actuating rod 61, and the cavities or baffles at the upper and lower ends of the hydraulic chamber 64 cooperate with the annular supporting structure to radially support the actuating rod 61.

[0060] When a support ring is fixedly arranged at the upper end of the hydraulic chamber 64, during the movement of the actuating rod 61, the support ring limits and supports the upward extending end of the actuating rod 61, and the cooperation between the support ring and the first limiting hole 66 provides more stable radial support for the actuating rod 61.

[0061] In this embodiment, the upper support ring, the first limiting hole 66 and the lower support ring cooperate to provide radial support for the actuating rod 61.

[0062] Furthermore, the upper end of the hydraulic chamber 64 has a second limiting hole 67, and the first limiting hole 66 and the second limiting hole 67 allow the actuating rod 61 to move longitudinally; the support ring is arranged at the first limiting hole 66, and the support ring is arranged at the second limiting hole 67.

[0063] It should be noted that the actuating rod 61 is of a hollow rod structure, and the upward extending end of the actuating rod 61 passes through the second limiting hole 67 to the outside of the hydraulic chamber 64, and the first limiting hole 66 and the second limiting hole 67 radially constrain the actuating rod 61. In this embodiment, the support ring is fixedly arranged inside the limiting hole. In other feasible embodiments, the support ring can be arranged on the outside of the limiting hole away from the hydraulic chamber 64. Annular support grooves are provided at both the first limiting hole 66 and the second limiting hole 67, and the support grooves are used for fixedly installing the support ring. The support ring can be made of metal, ceramic or wear-resistant polymer material.

[0064] In this embodiment, by radially limiting the upper and lower ends of the actuating rod 61, support rings are further arranged at the first limiting hole 66 and the second limiting hole 67 to provide radial support for the upper and lower ends of the actuating rod 61.

[0065] Furthermore, both the lower ends of the first actuating rod 61 and the second actuating rod 61 have connection holes 68, and the connection holes 68 are connected to the engine 1 through a pull rod bearing, and the actuating rod 61 transmits the force and torque of the engine 1.

[0066] In other feasible embodiments, the connection hole 68 can be connected to the main bracket of the front shock absorber 3 of the engine 1 through a pull rod bearing to connect to the engine 1. The main bracket of the front shock absorber 3 is directly installed on the engine 1 through bolts, and the actuating rod 61 is connected to the engine 1 by connecting to the main bracket of the front shock absorber 3.

[0067] Further, the accumulator 60 includes: an energy storage chamber 601, a spring 602, an indicating rod 603, and an accumulator piston 604; the energy storage chamber 601 has a storage end and a pressure end, and the storage end is connected to the hydraulic system connecting pipe 59; the indicating rod 603 and the spring 602 are arranged at the pressure end, the indicating rod 603 is connected to the accumulator piston 604 and moves with the accumulator piston 604, and the pressure of the hydraulic system can be detected by detecting the position of the indicating rod 603; the spring 602 is sleeved on the indicating rod 603 and presses the accumulator piston 604 to compensate for the pressure of the hydraulic system.

[0068] It should be noted that the storage end stores the hydraulic oil of the hydraulic system; in the initial stage, the accumulator 60 is filled with hydraulic oil, the liquid level is the highest, and the compression amount of the spring 602 is the largest. If there is a hydraulic oil leakage, when the hydraulic oil leakage is small, the pressure exerted by the spring 602 on the accumulator piston 604 can compensate for the pressure of the hydraulic system and make the storage end of the energy storage chamber 601 and the entire hydraulic system filled with hydraulic oil, and it can still play an anti-torsion role when a small amount of oil leaks from the hydraulic anti-torsion device. The indicating rod 603 is connected to the accumulator piston 604. When the liquid level in the accumulator 60 changes, the accumulator piston 604 drives the indicating rod 603 to move, and the pressure of the hydraulic system can be detected by detecting the moving distance of the indicating rod 603 or the position of the indicating rod 603. A certain displacement distance length range or the position of the indicating rod 603 is calibrated on the indicating rod 603, and when the displacement distance length range or the position of the indicating rod 603 is reached, the corresponding prompt of the hydraulic position is output in time. The prompt can be: supplement hydraulic oil, replace the hydraulic anti-torsion device, etc.

[0069] Exemplarily, the position of the indicating rod 603 can be judged by calibrating an indicating area on the indicating rod 603 and judging the pressure of the hydraulic system according to the indicating area pointed by the fixed point of the accumulator 60. The moving distance of the indicating rod 603 can be detected by a displacement detection device, and the pressure of the hydraulic system is judged according to the moving distance.

[0070] In this embodiment, the indicating rod 603 is connected to the accumulator piston 604 and moves with it. The pressure of the hydraulic system can be detected by detecting the moving distance of the indicating rod 603 or the position of the indicating rod 603. When the pressure of the hydraulic system decreases, the hydraulic oil leaks, and when the pressure decreases to a certain range, the corresponding prompt is output in time.

[0071] Further, a through hole is provided at the pressure end, the top end of the indicating rod 603 passes through the through hole, and the display length of the indicating rod 603 outside the accumulator 60 changes as the accumulator piston 604 moves.

[0072] It should be noted that the indicating length of the indicating rod 603 outside the accumulator 60 changes following the position of the accumulator piston 604. When the liquid level drops, the indicating length decreases. In a feasible implementation manner, different positions of the indicating rod 603 can be pointed to according to the fixed position of the through hole.

[0073] In this embodiment, by detecting the change in the displayed length of the indicating rod 603 outside the accumulator through hole 605, the pressure in the hydraulic system can be obtained. In other feasible implementation manners, the accumulator 60 can adopt a visual window with fixed position marks on it, and the indicating rod 603 has observable display length scale marks in the accumulator cavity 601. The pressure in the hydraulic system can be detected through the scale change of the fixed position.

[0074] In other feasible implementation manners, the indicating rod 603 and the accumulator piston 604 can be separately arranged and connected by a connection structure. The connection structure is specifically: threaded connection, key connection, etc.

[0075] Furthermore, an indicating area is divided on the indicating rod 603. The indicating area includes a high hydraulic pressure area, a medium hydraulic pressure area, and a low hydraulic pressure area; as the indicating rod 603 moves, the accumulator 60 can indicate different current indicating areas to display the pressure of the hydraulic system in the current indicating area.

[0076] It should be noted that the high hydraulic pressure area, the medium hydraulic pressure area, and the low hydraulic pressure area can be distinguished by colors. By pointing the fixed position on the accumulator 60 to different indicating areas, the current pressure of the hydraulic system can be displayed. The fixed position can be the above-mentioned accumulator through hole 605, the fixed position of the visual window of the accumulator 60, etc.

[0077] In this embodiment, the liquid level of the accumulator 60 is visualized by setting the indicating rod 603, which can intuitively judge the pressure of the hydraulic system and timely detect the oil leakage situation of the hydraulic system.

[0078] In other feasible implementation manners, the hydraulic system accumulator 60 is also provided with a displacement detection device to measure the displacement of the indicating rod 603.

[0079] It should be noted that in this embodiment, the indicating rod 603 is directly connected to the piston of the hydraulic system. By directly measuring the displacement of the indicating rod 603 through the displacement detection device, the pressure of the hydraulic system can be detected to obtain the oil leakage situation of the hydraulic system according to the system pressure.

[0080] In this embodiment and the above embodiments, the accumulator piston 604 has an annular groove, which is arranged on the contact surface between the accumulator piston 604 and the inner wall of the accumulator cavity 601. A sealing ring is installed in the annular groove to seal and fit the inner wall of the accumulator cavity 601, which can better maintain the sealing performance of the hydraulic system and prevent hydraulic oil leakage.

[0081] Furthermore, a throttle orifice 69 is provided at the connection between the accumulator 60 and the hydraulic system connecting pipe 59.

[0082] In this embodiment, the accumulator 60 is connected to the connecting pipe 59 through the throttle orifice 69 to slow down the flow rate of the accumulator 60 and prevent the accumulator 60 from being impacted due to excessive pressure changes in the hydraulic system.

[0083] Based on the above embodiments, the present application further provides a method for detecting the pressure of a hydraulic system accumulator, which is applied to the hydraulic system accumulator as described above. The method includes: Step 10, monitoring the area indicated by the indicating rod to monitor the accumulator liquid level; Step 20, outputting a corresponding accumulator pressure prompt according to the accumulator liquid level.

[0084] It should be noted that multiple indicating areas are divided on the indicating rod of the accumulator, and different indicating areas represent different accumulator liquid levels. When the accumulator liquid level decreases, the pressure in the accumulator decreases, indicating a hydraulic oil leakage in the hydraulic system. When a small amount of hydraulic oil leaks, the hydraulic system can still play an anti-torsion role. When the amount of hydraulic oil leakage is too large, the anti-torsion device of the hydraulic system needs to be replaced in time. In this embodiment, the accumulator pressure is monitored by monitoring the accumulator liquid level.

[0085] Furthermore, the indicating areas of the indicating rod include a high accumulator liquid level area, a medium accumulator liquid level area, and a low accumulator liquid level area; The above step 20 of outputting a corresponding accumulator pressure prompt according to the accumulator liquid level includes: Step 201, if it is monitored that the indicating area of the indicating rod is the high hydraulic area of the accumulator, continue to monitor; Step 202, if it is monitored that the indicating area of the indicating rod is the medium hydraulic area of the accumulator, output a prompt that the pressure has decreased and liquid needs to be replenished; Step 203, if it is monitored that the indicating area of the indicating rod is the low hydraulic area of the accumulator, output a prompt that the pressure is insufficient and the hydraulic system needs to be replaced.

[0086] In this embodiment, each indicating area of the indicating rod is calibrated in advance according to experimental measurements, and each indicating area represents different accumulator liquid levels and different hydraulic ranges of the hydraulic system. The pressure of the hydraulic system can be detected by detecting the indicating area of the indicating rod. When the pressure of the hydraulic system decreases, hydraulic oil leaks, and when the pressure decreases to the calibrated range, a corresponding prompt is output in time.

[0087] In summary, the present invention optimizes the connection method between the rear shock absorber, the front shock absorber and the torque compensation device, and the torque compensation device, further optimizing the various performances of the product, improving its practicability in the application of propeller aircraft, and making it have a better application prospect. The connection position of the main bolt is set at the position between the two rubber piles of the second rubber component and the first rubber component. In this way, as long as a main bolt is used to press the second rubber component and the first rubber component against the bottom surface and the top surface of the main bracket component, the rubber bodies in the second rubber component and the first rubber component can be pre-compressed. Thus, compared with the prior art, the connection structure of one connecting bolt is reduced, the pre-compression structure of the rubber component is simplified, the installation steps are simplified, and the weight of the entire rear shock absorber device is reduced, meeting the requirements of lightweight design. In addition, with such a setting, the area of the third metal skeleton in the prior art is also reduced, further reducing the weight of the entire rear shock absorber device. By designing the values of the gap H1 and the gap H2, the pre-compression amount of the rubber bodies in the second rubber component and the first rubber component can be accurately controlled. After the bolt and nut reach the designed tightening torque, the sleeve generates metal rigid limit to ensure the designed compression state of the rubber, ensuring that the rubber parts do not loosen under the engine load condition of the rear shock absorber. When subjected to excessive impact or vibration, a rigid limit structure is formed by the contact between the outer peripheral surface of the first sleeve and the outer peripheral surface of the second sleeve and the inner peripheral surface of the third through hole, so that the present invention can limit the deformation degree of the shock absorber when subjected to excessive impact or vibration, thereby protecting the shock absorber and the engine from damage, ensuring that the shock absorber works within the predetermined stroke range, and avoiding failures or damages caused by exceeding the design range. By optimizing the connection method, the present invention can realize the connection function between the front shock absorber and the torque compensation device. Thus, when the load changes, the torque compensator can automatically adjust the output torque to maintain the stable operation of the engine, reduce the vibration and noise levels, and thus improve the flight safety and comfort. By designing the nut as an elastic nut, using its elastic support on the inner peripheral surface of the first through hole, and then using the first through hole to limit the rotation of the elastic nut, in fact, the elastic nut can only move axially in the first through hole and cannot rotate. During operation, the elastic nut is moved to the inserted bolt rod part, and then the rotating bolt and the rotation-limited elastic nut are used in cooperation to lock, so that the bolt can be locked conveniently and quickly in a narrow installation space, reducing the working intensity and improving the working efficiency. By setting the positioning disc and the positioning through hole to cooperate to form a positioning structure, the working intensity can be further reduced and the working efficiency can be improved. By optimizing the torque compensation device, the reaction torque generated by the engine propeller can be limited, and it also has a radial support part to radially support the actuating rod, and the radial support part cooperates with the first limiting hole to provide radial support for the actuating rod. The radial support part can specifically be a support structure on the actuating rod or a support ring provided on the hydraulic chamber.It can prevent the hydraulic oil leakage caused by the offset of the actuator rod of the hydraulic device due to the radial force of the engine, resulting in a gap between the piston sealing ring and the cylinder wall.

[0088] In the embodiments, the "plurality" refers to the number of "two or more". The above embodiments are only for illustrating the present invention, rather than limiting the present invention. Those skilled in the relevant technical field can also make various changes or transformations without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also fall within the protection scope of the present invention, and the protection scope of the present invention should be defined by each claim.

Claims

1. A method for arranging a turboprop engine, wherein the turboprop engine is arranged on an aircraft frame through a vibration reduction system, wherein the vibration reduction system comprises: Two front side shock absorbers and one front upper shock absorber installed between the aircraft frame and the turboprop engine near the front side of the engine; Two rear shock absorbers are installed between the aircraft frame and the turboprop engine near the rear side of the engine; a torque compensation device is also arranged on the aircraft frame at the front side of the engine, and the torque compensation device is connected to the two front shock absorbers; the two front shock absorbers and the two rear shock absorbers are respectively located at the two sides of the turboprop engine, and the front upper shock absorber is located at the top of the turboprop engine, characterized in that: the turboprop engine arrangement method includes optimizing the pre-compression method of the rubber component in the rear shock absorber, that is, the rear shock absorber also includes a main bracket assembly, the rubber component includes a rubber component 1 and a rubber component 2, the main bracket assembly is arranged between the rubber component 1 and the rubber component 2, and during installation, the main bolt is sequentially passed through the middle position of the rubber component 2, the middle position of the main bracket assembly and the rubber component 1, and then locked with the nut, so that the rubber component 2 and the rubber component 1 are pressed against the bottom surface and the top surface of the main bracket assembly, so that the rubber bodies in the rubber component 2 and the rubber component 1 are in a pre-compressed state.

2. The turboprop engine arrangement method according to claim 1, characterized in that: The rubber component 2 and the rubber component 1 both include a top plate, a bottom plate 1 and a bottom plate 2, the rubber bodies in the rubber component 2 and the rubber component 1 both include a rubber pile 1 and a rubber pile 2, the bottom plate 1 is vulcanized and bonded to the top plate through the rubber pile 1, the bottom plate 2 is vulcanized and bonded to the top plate through the rubber pile 2, the rubber pile 1 and the rubber pile 2 are respectively located at the two 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 2, the main bracket component and the through hole of rubber component 1 in sequence and is then locked with the nut. After locking, the bottom plate 1 and bottom plate 2 of rubber component 2 are in contact with the bottom surface of the main bracket component, and the bottom plate 1 and bottom plate 2 of rubber component 1 are in contact with the top surface of the main bracket component.

3. The turboprop engine arrangement method according to claim 2, characterized in that: The main bolt passing through the main bracket assembly is connected with one end of the mounting frame assembly through the ball bearing 1, and the outer part of the main bolt is also sleeved with a shaft sleeve 1 and a shaft sleeve 2; the shaft sleeve 1 is located between the top plate of the rubber assembly 1 and the ball bearing 1, and the shaft sleeve 2 is located between the top plate of the rubber assembly 2 and the ball bearing 1; Before pre-compression, one end of the sleeve 1 contacts the top plate of the rubber component 1, and a gap H1 is left between the other end of the sleeve 1 and the end face of one end of the inner ring of the ball bearing 1; one end of the sleeve 2 contacts the top plate of the rubber component 2, and a gap H2 is left between the other end of the sleeve 2 and the end face of the other end of the inner ring of the ball bearing 1; after the main bolt is tightened for pre-compression, the gaps H1 and H2 are both zero; By designing the values ​​of the gap H1 and the gap H2, the pre-compression amount of the rubber body in the rubber component 2 and the rubber component 1 can be controlled.

4. The turboprop engine arrangement method according to claim 3, characterized in that: The turboprop engine vibration reduction system optimization method also includes optimizing the rigid limit structure of the rubber component in the rear shock absorber, namely: the mounting frame assembly includes a mounting frame body, a ball bearing one mounting hole is arranged at one end of the mounting frame body, and the main bracket assembly includes a main bracket frame body, and a through hole three is arranged at the middle position of the main bracket frame body; when one end of the mounting frame assembly is inserted into one side of the main bracket assembly, the central axis of the ball bearing one mounting hole coincides with the central axis of the through hole three; after installation, the ball bearing one is arranged at a position between the outside of the rod body of the main bolt and the ball bearing one mounting hole, so that the main bolt passing through the main bracket assembly is connected with one end of the mounting frame assembly through the ball bearing one; The shaft sleeve 1 and the shaft sleeve 2 are both located in the through hole 3, and a gap H4 is left between the outer circumference of the shaft sleeve 1 and the inner circumference of the through hole 3, and a gap H5 is left between the outer circumference of the shaft sleeve 2 and the inner circumference of the through hole 3; When subjected to excessive impact force or vibration, a rigid limiting structure is formed by the contact between the outer circumference of the shaft sleeve one and the outer circumference of the shaft sleeve two and the inner circumference of the through hole three.

5. The turboprop engine arrangement method according to claim 4, characterized in that: The turboprop engine arrangement method further includes optimizing the installation method between the rear shock absorber and the aircraft frame, that is, a ball bearing second installation hole and a ball bearing third installation hole are provided on the main bracket assembly, the ball bearing in the screw rod one with the ball bearing is the ball bearing second, and the ball bearing in the screw rod two with the ball bearing is the ball bearing third; After installation, ball bearing two is arranged at a position between one end of screw rod one and the mounting hole of ball bearing two, so that one end of screw rod one is connected with the main bracket assembly through ball bearing two, ball bearing three is arranged at a position between one end of screw rod two and the mounting hole of ball bearing three, so that one end of screw rod two is connected with the main bracket assembly through ball bearing three, and the other ends of screw rod one and screw rod two are connected to the aircraft frame.

6. The turboprop engine arrangement method according to claim 5, characterized in that: A mounting arm 1 and a mounting arm 2 are provided on the aircraft frame, a mounting through hole 1 is provided on one end of the mounting arm 1, and a mounting through hole 2 is provided on one end of the mounting arm 2; When connecting, the other end of screw rod one is passed through installation through hole one and then locked with installation nut one, and the other end of screw rod two is passed through installation through hole two and then locked with installation nut two, so that the other ends of screw rod one and screw rod two are connected to the aircraft frame.

7. The turboprop engine arrangement method according to claim 6, characterized in that: The main support assembly also includes a rotating arm, a connecting arm and a hanging ear are arranged on one side of the main support frame, the connecting arm and the hanging ear are an integral structure with the main support frame, one end of the rotating arm is hinged to the hanging ear, a second mounting hole of the ball bearing is arranged on the connecting arm, and a third mounting hole of the ball bearing is arranged on the other end of the rotating arm; When connecting, first connect the screw rod 1 with the ball bearing to the mounting arm 1. After the connection is completed, adjust the installation position of the screw rod 2 with the ball bearing according to the actual position of the mounting through hole 2, and then connect the screw rod 2 with the ball bearing to the mounting arm 2.

8. The turboprop engine arrangement method according to any one of claims 1 to 7, characterized in that: The turboprop engine arrangement method includes optimizing the hydraulic anti-torsion device of the engine vibration reduction system, that is, the hydraulic anti-torsion device of the engine vibration reduction system includes: an actuator, a connecting pipe and an accumulator; the actuator includes a first actuator and a second actuator, and the actuator has an actuating rod; the oil storage end of the first actuator and the oil storage end of the second actuator are at different upper and lower positions, the oil storage end of the first actuator and the oil storage end of the second actuator are connected through a connecting pipe, and the accumulator is connected to the connecting pipe; the actuating rod includes a first actuating rod and a second actuating rod, both of which are connected to the engine, the first actuating rod is arranged in the first actuator; the second actuating rod is arranged in the second actuator; The optimization of the hydraulic anti-torsion device of the engine vibration reduction system is to design the actuator into a piston sealing ring, a hydraulic chamber, and a radial support portion; the piston sealing ring is an annular structure that contacts the inner wall of the hydraulic chamber and is arranged on the actuating rod; the actuating rod extends upward to the outside of the hydraulic chamber; the radial support portion provides radial support for the actuating rod when the actuating rod moves.

9. The turboprop engine arrangement method according to claim 8, characterized in that: The accumulator comprises: an energy storage chamber, a spring, an indicator rod and an accumulator piston; the energy storage chamber has a storage end and a pressure end, and the storage end is connected to a hydraulic system connecting pipe; the indicator rod and the spring are arranged at the pressure end, the indicator rod is connected to the accumulator piston and moves with the accumulator piston, and the hydraulic system pressure can be detected by detecting the position of the indicator rod; the spring is sleeved on the indicator rod and press-fitted on the accumulator piston to compensate for the hydraulic system pressure.

10. A vibration reduction system, comprising: Two front side shock absorbers and one front upper shock absorber installed between the aircraft frame and the turboprop engine near the front side of the engine; Two rear shock absorbers are installed between the aircraft frame and the turboprop engine near the rear side of the engine; a torque compensation device is also arranged on the aircraft frame at the front side of the engine, and the torque compensation device is connected to the two front shock absorbers; the two front shock absorbers and the two rear shock absorbers are respectively located on both sides of the turboprop engine, and the front upper shock absorber is located at the top of the turboprop engine, characterized in that: the rear shock absorber includes a rubber component and a main bracket component, the rubber component includes a rubber component 1 and a rubber component 2, the main bracket component is arranged between the rubber component 1 and the rubber component 2, and during installation, the main bolt is used to pass through the middle position of the rubber component 2, the middle position of the main bracket component and the rubber component 1 in sequence, and then locked with the nut, so that the rubber component 2 and the rubber component 1 are pressed against the bottom surface and the top surface of the main bracket component, so that the rubber bodies in the rubber component 2 and the rubber component 1 are in a pre-compressed state.

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