Flexible shaft connecting structure for aviation motor

Abstract

The utility model relates to the technical field of aero-generators, and provides a flexible shaft connecting structure for an aero-motor, which comprises a hollow shaft, a flexible shaft body and a damping disc, the hollow shaft is arranged in a generator and serves as an input end of the generator, and an annular friction surface is arranged outside one end of the hollow shaft; the flexible shaft body is concentrically arranged in the hollow shaft, the end, located in the hollow shaft, of the flexible shaft body is fixed to the end, away from the friction face, of the hollow shaft, and the other end of the flexible shaft body extends out of the hollow shaft. According to the flexible shaft connecting structure for the aviation motor, the friction surface and the damping disc are arranged, and the inner conical surface matched with the friction surface is arranged on the damping disc, so that the flexible shaft and the hollow shaft are prevented from generating relative offset, and after the flexible shaft and the hollow shaft generate offset, the flexible shaft and the hollow shaft are corrected through the elastic damping disc and the friction surface; the transmission reliability of the hollow shaft and the flexible shaft is improved, and the resonance problem caused by the generator flexible shaft is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of aviation generators, in particular to a flexible shaft connection structure for aviation motors. Background Art

[0002] In the 1950s, the increasing maturity of brushless DC motors and contactless switchgear laid the foundation for the development of aircraft high-voltage DC power systems. The three-stage generator is used in the field of aviation high-voltage DC power supply due to its unique performance advantages. The three-stage generator adopts advanced magnetoelectric technology and precise control system, which can maintain stable output under various flight conditions. The main advantages of the three-stage generator include high efficiency, low noise and long life. Its modular design facilitates maintenance and replacement, reducing ground downtime. In addition, the three-stage generator also has good overload capacity and anti-interference performance, ensuring that the aircraft's electronic equipment and systems can still operate normally under various extreme conditions.

[0003] In domestic internal combustion engine units, the generator generally adopts a hard shaft connection method, and the generator and engine transmission are generally connected by a coupling, which transmits torque and absorbs the pulsation and impact of the prime mover through the coupling. However, due to the impossibility of absolute precision in manufacturing and installation, as well as the elastic deformation and temperature difference deformation of the foundation, frame and other parts during working load, the two axes connected by the coupling will inevitably produce relative offset. In the prior art, for example, a soft shaft driven generator with a publication number of CN101783538A uses a soft shaft made of spring steel, which effectively prevents the rotor speed from pulsating when the piston engine is dragged, can buffer the impact, compensate for the non-concentricity between the drive device and the motor shaft, and thus has better shock absorption performance and can reduce bearing wear.

[0004] However, since the mating surface of the flexible shaft and the hollow shaft is at the rear end of the generator, only the hollow shaft at the rear end of the generator shaft and the flexible shaft can be guaranteed to be concentric. The large swing of the flexible shaft at the driving end will cause the flexible shaft and the hollow shaft to be non-concentric, causing the flexible shaft driving end to be eccentric when working, thereby causing the flexible shaft and the rotor assembly to vibrate, affecting the reliability of the generator. Utility Model Content

[0005] In view of this, the utility model proposes a flexible shaft connection structure for an aviation motor, by setting a friction surface and a damping disk, and setting an inner conical surface matching the friction surface on the damping disk to prevent the flexible shaft and the hollow shaft from generating relative offset, and after the flexible shaft and the hollow shaft generate offset, correction is performed through the elastic damping disk and the friction surface, thereby improving the reliability of the transmission between the hollow shaft and the flexible shaft, and solving the resonance problem caused by the flexible shaft of the generator.

[0006] The technical solution of the utility model is implemented as follows: The utility model provides a flexible shaft connection structure for an aviation motor, comprising a hollow shaft, a flexible shaft body and a damping disk, wherein:

[0007] The hollow shaft is arranged in the generator and serves as the input end of the generator, and an annular friction surface is arranged outside one end of the hollow shaft;

[0008] The flexible shaft body is coaxially arranged in the hollow shaft, and one end of the flexible shaft body located in the hollow shaft is fixed to an end of the hollow shaft away from the friction surface, and the other end of the flexible shaft body extends to the outside of the hollow shaft;

[0009] The damping disc is fixed on the flexible shaft body and is located outside the hollow shaft. The damping disc is provided with an inner conical surface, which is concentric with the friction surface and abuts against each other. The damping disc is elastic.

[0010] On the basis of the above technical solution, preferably, it further comprises a friction ring, which is fixed at the end of the hollow shaft and is concentric with the hollow shaft, and the friction surface is located on a side of the friction ring away from the hollow shaft.

[0011] Further preferably, it further comprises a baffle, wherein the baffle is fixedly mounted on the end of the hollow shaft, and the friction ring is fixed to the baffle.

[0012] On the basis of the above technical solution, preferably, it further comprises a connecting component, wherein the connecting component is arranged on the flexible shaft body, and the connecting component is used to connect the damping disk and the flexible shaft body.

[0013] Further preferably, the connecting assembly includes a limit seat, the limit seat is arranged on the outside of the flexible shaft body and is fixed to the flexible shaft body, the limit seat is provided with a retaining ring, the damping disc is arranged on the limit seat and is abutted against the retaining ring, and the retaining ring is used to prevent the damping disc from moving axially toward the side away from the hollow shaft.

[0014] More preferably, the connection assembly further comprises a limiting tooth, the limiting tooth is arranged on the limiting seat, and the limiting tooth is engaged with the damping disk to prevent the damping disk and the flexible shaft body from rotating relative to each other.

[0015] Based on the above technical solution, preferably, the cone angle of the inner cone is 120°-174°.

[0016] On the basis of the above technical solution, preferably, the flexible shaft body is a spring steel component.

[0017] On the basis of the above technical solution, preferably, one end of the flexible shaft body away from the hollow shaft is configured as a spline shaft.

[0018] The flexible shaft connection structure for aviation motors of the utility model has the following beneficial effects compared with the prior art:

[0019] (1) By providing a friction surface and a damping disk, and providing an inner conical surface on the damping disk that matches the friction surface, the relative offset between the flexible shaft and the hollow shaft is prevented. After the flexible shaft and the hollow shaft are offset, the elastic damping disk and the friction surface are used to correct the offset, thereby improving the reliability of the transmission between the hollow shaft and the flexible shaft and solving the resonance problem caused by the flexible shaft of the generator;

[0020] (2) By setting a connecting component, the diameter of the side of the limit seat away from the hollow shaft is larger than the diameter of the side close to the hollow shaft, so that the damping disc can be set on the limit seat by setting an opening, and the side with a larger diameter hinders the movement of the damping disc in the direction away from the hollow shaft, so that the damping disc can produce a small deformation under the push of the friction ring. At the same time, the limit teeth are set on the limit seat, and the limit teeth are engaged with the damping disc to hinder the relative rotation between the damping disc and the flexible shaft body. The limit seat and the limit teeth can facilitate the assembly of the damping disc, and improve the stability of the connection between the structures, so that the deformation of the damping disc does not affect the connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a three-dimensional diagram of the flexible shaft connection structure for aviation motors of the utility model;

[0023] Figure 2 It is a partial cross-sectional view of the flexible shaft connection structure for aviation motors of the utility model;

[0024] Figure 3 The utility model is a schematic diagram of a connection component of a flexible shaft connection structure for an aviation motor. DETAILED DESCRIPTION

[0025] The following will be combined with the implementation of the utility model to clearly and completely describe the technical solutions in the implementation of the utility model. Obviously, the described implementation is only a part of the implementation of the utility model, not all of the implementations. Based on the implementation of the utility model, all other implementations obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] In the 1950s, the increasing maturity of brushless DC motors and contactless switchgear laid the foundation for the development of aircraft high-voltage DC power systems. The three-stage generator is used in the field of aviation high-voltage DC power supply due to its unique performance advantages. The three-stage generator is generally composed of: flexible shaft assembly, rotor assembly, rotating rectifier, stator assembly and bridge rectifier, with the advantages of small size, light weight, good electrical performance, high reliability and high power density.

[0027] In order to prevent abnormal jamming of the generator operation and affect the aircraft engine shaft, the three-stage generator is generally designed with a hollow shaft and a flexible shaft. The flexible shaft is designed with a shear neck to ensure that the flexible shaft of the generator automatically breaks and disengages from the engine shaft when subjected to a certain torque to avoid damage to the engine. The rotor assembly consists of a permanent magnet auxiliary exciter rotor, an exciter rotor and a main generator rotor. The three rotors are coaxially installed, resulting in a longer generator rotor shaft. Therefore, it is particularly important to ensure the coaxiality of the hollow shaft and the flexible shaft when the generator is running. The general method of ensuring the concentricity of the hollow shaft and the flexible shaft in a three-stage aircraft generator is: the outer cone machined at the bottom of the rectangular spline at the rear end of the flexible shaft and the inner cone of the hollow shaft cooperate to ultimately ensure the concentricity of the motor flexible shaft spline and the motor drive end cover installation stop. However, this design has certain disadvantages. For example, since the mating surface of the flexible shaft and the hollow shaft is at the rear end, it can only ensure that the hollow shaft at the rear end of the generator shaft and the flexible shaft are concentric. The swing of the flexible shaft at the drive end is large, which can easily cause the flexible shaft and the hollow shaft to be non-concentric. When the flexible shaft drive end is eccentric during operation, it will cause resonance between the flexible shaft and the rotor assembly.

[0028] like Figure 1-3 As shown, the flexible shaft connection structure for aviation motors of the present invention is designed to solve the above-mentioned problem, and mainly includes a hollow shaft 1, a flexible shaft body 2 and a damping disc 3.

[0029] The hollow shaft 1 is arranged in the generator and serves as the input end of the generator. An annular friction surface 101 is arranged on the outside of one end of the hollow shaft 1. The hollow shaft 1 is the input shaft of the main generator rotor. The hollow shaft 1 is driven to rotate through the transmission, thereby driving the generator to generate electricity. The hollow shaft 1 is connected to the aircraft engine through the transmission and is driven by the aircraft engine to realize the power generation operation.

[0030] The flexible shaft body 2 is concentrically arranged in the hollow shaft 1, and one end of the flexible shaft body 2 located in the hollow shaft 1 is fixed to the end of the hollow shaft 1 away from the friction surface 101, and the other end of the flexible shaft body 2 extends to the outside of the hollow shaft 1. The flexible shaft body 2 is the part that is connected to the aircraft engine by transmission. The inner diameters of the two ends of the hollow shaft 1 are different. The length of the flexible shaft body 2 is greater than the hollow shaft 1 and is inserted into the hollow shaft 1. The flexible shaft body 2 is fixed to the end of the hollow shaft 1 with a smaller inner diameter. The fixing method can be a bolt or other connection method. The other end of the flexible shaft body 2 extends to the outside of the hollow shaft 1 and is transmitted to the generator so that the engine power can be transmitted to the hollow shaft 1 through the flexible shaft body 2. In this embodiment, the flexible shaft body 2 is made of spring steel.

[0031] On the hollow shaft 1 , an annular friction surface 101 surrounds the outside of the hollow shaft 1 and extends out of one end of the hollow shaft 1 toward the flexible shaft body 2 . The center of the friction surface 101 is located on the axis of the hollow shaft 1 and rotates with the hollow shaft 1 .

[0032] The damping disc 3 is fixed on the flexible shaft body 2 and is located on the outside of the hollow shaft 1. The damping disc 3 is provided with an inner conical surface 301. The inner conical surface 301 is concentric with the friction surface 101 and abuts against each other. The damping disc 3 is elastic. The damping disc 3 is arranged in a conical shape as a whole, and the bottom circle side is open. The inner conical surface 301 is the inner wall surface of the damping disc 3. The flexible shaft body 2 and the damping disc 3 are coaxial. The radius of the inner conical surface 301 on the damping disc 3 is greater than the radius of the friction surface 101. During the transmission process of the hollow shaft 1 and the flexible shaft body 2, the radial force generated by the generator rotor shaft during operation is decomposed into axial and radial forces through the inner conical surface 301 of the damping disc 3. The radial force is absorbed by the friction surface 101, and the axial force is transmitted to the hollow shaft 1 of the generator through the friction surface 101.

[0033] Therefore, the eccentricity of the front end of the generator flexible shaft body 2 can be corrected by the elastic damping disk 3 and the friction surface 101, ensuring that the flexible shaft body 2 and the hollow shaft 1 always remain concentric during the operation of the generator, while solving the resonance problem caused by the generator flexible shaft.

[0034] In this embodiment, a friction ring 4 is further included. The friction ring 4 is fixed at the end of the hollow shaft 1 and is concentric with the hollow shaft 1. The friction surface 101 is located on the side of the friction ring 4 away from the hollow shaft 1. The friction ring 4 is an annular component as a whole. The friction surface 101 is arranged on the friction ring 4. During assembly, the friction ring 4 is supported on the inner conical surface 301 of the damping disk 3 through the friction surface 101. Specifically, the friction ring 4 is made of graphite material. Graphite is soft and has good friction resistance.

[0035] Correspondingly, in order to assemble the friction ring 4, in the present embodiment, a baffle plate 5 is further provided, and the baffle plate 5 is fixedly mounted on the end of the hollow shaft 1, and the friction ring 4 is fixed to the baffle plate 5. Specifically, the baffle plate 5 is conically arranged on the outside, and the end is arranged to be an opening, and the hollow shaft 1 is fixed to the baffle plate 5 by inserting it into the opening and interfering with it. A mounting surface is also provided on the bottom circle of the baffle plate 5, and a limiting ring is provided on the outer side of the mounting surface. The friction ring 4 is fixed on the mounting surface and is arranged in the limiting ring, so that the friction ring 4 is fixed to the hollow shaft 1 through the baffle plate 5, forming a stable contact with the inner conical surface 301.

[0036] As a preferred embodiment, a connecting component 6 is also provided, and the connecting component 6 is arranged on the flexible shaft body 2. The connecting component 6 is used to connect the damping disk 3 and the flexible shaft body 2. Since the materials of the flexible shaft body 2 and the damping disk 3 are different, the damping disk 3 and the flexible shaft body 2 are connected by the connecting component 6, which can improve the assembly efficiency and avoid the adverse effects caused by welding.

[0037] Specifically, the connecting assembly 6 includes a limit seat 61, which is sleeved on the outside of the flexible shaft body 2 and fixed to the flexible shaft body 2. A retaining ring 611 is provided on the limit seat 61. The damping disk 3 is sleeved on the limit seat 61 and abutted against the retaining ring 611. The retaining ring 611 is used to prevent the damping disk 3 from moving axially toward the side away from the hollow shaft 1.

[0038] Among them, the limit seat 61 is fixed on the flexible shaft body 2 by interference fit to realize the fixation of the flexible shaft body 2 and the limit seat 61. The diameter of the side of the limit seat 61 away from the hollow shaft 1 is larger than the diameter of the side close to the hollow shaft 1, so that the damping disk 3 can be set on the limit seat 61 by setting an opening, and the side with a larger diameter hinders the movement of the damping disk 3 in the direction away from the hollow shaft 1, so that the damping disk 3 can produce a small deformation under the push of the friction ring 4. The side with a larger diameter of the limit seat 61 is the retaining ring 611.

[0039] In addition, the connecting component 6 also includes a limiting tooth 62, which is arranged on the limiting seat 61. The limiting tooth 62 is engaged with the damping disk 3 to prevent the damping disk 3 and the flexible shaft body 2 from rotating relative to each other. A matching tooth matched with the limiting tooth 62 is arranged on the damping disk 3, and the damping disk 3 is prevented from rotating by the engagement of the limiting tooth 62 with the matching tooth.

[0040] As a preferred embodiment, the cone angle of the inner cone 301 is 120°-174°, that is, the angle between the cone generatrix and the bottom radius is between 3°-30°. If the angle between the cone generatrix and the bottom radius is too small, the effect of hindering the vibration of the flexible shaft body 2 will be poor, while if the angle is too large, the damping disk 3 will produce a large deformation during use, which is not conducive to the stability of the structure.

[0041] In this embodiment, in order to connect the output end of the engine, the end of the flexible shaft body 2 away from the hollow shaft 1 is set as a spline shaft, and the flexible shaft body 2 performs transmission operation between the engine and the generator through spline cooperation.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A flexible shaft connection structure for an aviation motor, characterized in that: It comprises a hollow shaft (1), a flexible shaft body (2) and a damping disc (3), wherein: The hollow shaft (1) is arranged in the generator and serves as the input end of the generator, and an annular friction surface (101) is arranged on the outside of one end of the hollow shaft (1); The flexible shaft body (2) is coaxially arranged in the hollow shaft (1), and one end of the flexible shaft body (2) located in the hollow shaft (1) is fixed to an end of the hollow shaft (1) away from the friction surface (101), and the other end of the flexible shaft body (2) extends to the outside of the hollow shaft (1); The damping disc (3) is fixed on the flexible shaft body (2) and is located outside the hollow shaft (1). The damping disc (3) is provided with an inner conical surface (301). The inner conical surface (301) and the friction surface (101) are concentric and mutually abutted. The damping disc (3) is elastic.

2. The flexible shaft connection structure for an aviation motor according to claim 1, characterized in that: It also comprises a friction ring (4), which is fixed at the end of the hollow shaft (1) and is concentric with the hollow shaft (1), and the friction surface (101) is located on the side of the friction ring (4) away from the hollow shaft (1).

3. The flexible shaft connection structure for an aviation motor according to claim 2, characterized in that: It also comprises a baffle (5), wherein the baffle (5) is fixedly mounted on the end of the hollow shaft (1), and the friction ring (4) is fixed to the baffle (5).

4. The flexible shaft connection structure for an aviation motor according to claim 1, characterized in that: It also comprises a connecting component (6), wherein the connecting component (6) is arranged on the flexible shaft body (2), and the connecting component (6) is used to connect the damping disc (3) and the flexible shaft body (2).

5. The flexible shaft connection structure for an aviation motor according to claim 4, characterized in that: The connecting assembly (6) comprises a limit seat (61), the limit seat (61) is sleeved on the outside of the flexible shaft body (2) and fixed to the flexible shaft body (2), a retaining ring (611) is provided on the limit seat (61), the damping disc (3) is sleeved on the limit seat (61) and abuts against the retaining ring (611), and the retaining ring (611) is used to prevent the damping disc (3) from moving in the axial direction toward a side away from the hollow shaft (1).

6. The flexible shaft connection structure for an aviation motor according to claim 5, characterized in that: The connection assembly (6) further comprises a limiting tooth (62), wherein the limiting tooth (62) is arranged on the limiting seat (61), and the limiting tooth (62) is engaged with the damping disc (3) to prevent the damping disc (3) and the flexible shaft body (2) from rotating relative to each other.

7. The flexible shaft connection structure for an aviation motor according to claim 1, characterized in that: The cone angle of the inner cone (301) is 120°-174°.

8. The flexible shaft connection structure for an aviation motor according to claim 1, characterized in that: The flexible shaft body (2) is a spring steel component.

9. The flexible shaft connection structure for an aviation motor according to claim 1, characterized in that: One end of the flexible shaft body (2) away from the hollow shaft (1) is arranged as a spline shaft.

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