Main bearing locking nut anti-loosening structure and aero-engine

Abstract

The invention relates to a main bearing locking nut anti-loosening structure and an aero-engine, belongs to the technical field of aerospace, and solves the problem of unreliable mechanical anti-loosening locking of a locking nut in the prior art. The anti-rotation device comprises a locking nut, a locking plate and an anti-rotation sleeve which are arranged outside a shaft neck of an engine rotating shaft in a sleeving mode. The locking nut fixing section is fixed to the shaft neck, and a first groove is formed in the outer portion of the clamping section in the circumferential direction. The locking plate comprises a locking plate main body, a first tooth and a second tooth; the first tooth is embedded into the first groove to limit the circumferential movement of the locking nut; the anti-rotation sleeve fixing part is connected with the shaft neck; the inner wall face of the anti-rotation part is attached to the outer wall face of the locking nut and the outer wall face of the locking piece. And the end part of the anti-rotation part is provided with a notch which is mutually embedded with the second tooth. Triple locking of the main bearing locking nut can be achieved, locking is reliable, and the structure is simple.

Description

Technical Field

[0001] The present invention relates to the field of aerospace technology, and in particular to a loosening prevention structure for a main bearing locking nut and an aeroengine. Background Art

[0002] An aeroengine requires that the main bearing locking nut of the engine does not loosen during the entire life cycle, so as to always ensure the preloading of the locking nut and the normal working state of the main bearing. However, due to the long-term action of alternating loads and vibrations during the working state, the main bearing of the engine is prone to loosen, resulting in a decrease in the preloading force of the locking nut or even its detachment.

[0003] At present, the loosening prevention methods for the main bearing locking nuts of engines mostly use "T"-shaped lock washers, cup washers, pins, etc. to simply mechanically prevent and lock the locking nuts. In a long-term vibration and shock environment, the components of the mechanical loosening prevention structure are prone to deformation, fracture or detachment, thereby losing the loosening prevention function and causing the locking nut to loosen again. Summary of the Invention

[0004] In view of the above analysis, embodiments of the present invention aim to provide a loosening prevention structure for a main bearing locking nut and an aeroengine to solve the problem of unreliable mechanical loosening prevention and locking of the locking nut in the prior art.

[0005] The object of the present invention is mainly achieved through the following technical solutions:

[0006] In a first aspect of the present invention, a loosening prevention structure for a main bearing locking nut is provided, including a locking nut, a lock washer and an anti-rotation sleeve sleeved on the outer part of the journal of an engine rotating shaft;

[0007] The locking nut includes a fixed section and a clamping section; the fixed section is fixed to the journal, and a first groove is circumferentially provided on the outer part of the clamping section;

[0008] The lock washer includes a lock washer body, a first tooth and a second tooth; the first tooth is embedded in the first groove to limit the circumferential movement of the locking nut;

[0009] The anti-rotation sleeve includes a fixed part and an anti-rotation part; the fixed part is connected to the journal; the inner wall surface of the anti-rotation part is attached to the outer wall surfaces of the locking nut and the lock washer; and a notch that is mutually engaged with the second tooth is provided at the end of the anti-rotation part.

[0010] Furthermore, a spiral retaining ring is further included; a clamping groove is provided inside the anti-rotation part near the notch, and the outer edge of the spiral retaining ring abuts against the bottom surface of the clamping groove; and the inner end surface of the spiral retaining ring is attached to the outer end surface of the second tooth.

[0011] Furthermore, the lock washer body is cylindrical.

[0012] Further, the first teeth are uniformly arranged circumferentially at the rear end of the lock piece body and extend outward along the axial direction from the circumferential edge of the rear end face of the lock piece body; the first teeth are engaged with the first grooves.

[0013] Further, the second teeth are uniformly arranged circumferentially at the front end of the lock piece body and extend outward radially from the circumferential edge of the front end face of the lock piece body.

[0014] In a second aspect of the present invention, an aeroengine is provided, which includes a rotating shaft, a main bearing assembly, and the anti-loosening structure of the main bearing locking nut.

[0015] Further, the journal of the rotating shaft includes a threaded section and a non-threaded section; the threaded section has an external thread, and the fixed section of the locking nut has an internal thread, and the internal thread is screwed with the external thread.

[0016] Further, the main bearing assembly includes a main bearing inner ring; the fixing portion is arranged between the locking nut and the main bearing inner ring.

[0017] Further, the fixing portion includes a first fitting surface and a second fitting surface;

[0018] The first fitting surface is in contact with the inner end face of the locking nut, and the second fitting surface is in contact with the end face of the main bearing inner ring.

[0019] Further, protrusions are uniformly arranged circumferentially at the end edge of the fixing portion, and the protrusions extend radially inward;

[0020] The non-threaded section of the rotating shaft is provided with second grooves; the protrusions are engaged with the second grooves.

[0021] Compared with the prior art, the present invention can at least achieve one of the following beneficial effects:

[0022] (1) Compared with the prior art, in the present invention, the first teeth of the lock piece are embedded in the first grooves of the engaging section of the locking nut, and the anti-rotation sleeve is sleeved outside the locking nut to limit the circumferential movement of the locking nut, jointly realizing the anti-loosening of the locking nut; the fixing portion of the anti-rotation sleeve is fixed to the journal, the anti-rotation portion is sleeved outside the lock piece, and the notch at the end of the anti-rotation portion is engaged with the second teeth of the lock piece to limit the circumferential movement of the lock piece, jointly realizing the anti-loosening of the lock piece; the engagement of the notch and the second teeth also limits the circumferential movement of the anti-rotation portion, synchronously realizing the anti-loosening of the anti-rotation sleeve. The present invention realizes the anti-loosening of the locking nut, the lock piece, and the anti-rotation sleeve in the anti-loosening structure, avoiding the anti-loosening failure caused by the deformation and falling off of the anti-loosening components when only the locking nut is anti-loosened. The structure is simple and reliable, and the installation and disassembly are convenient.

[0023] (2) In the present invention, a clamping groove is provided inside the anti-rotation sleeve, into which a spiral retaining ring is inserted. The spiral retaining ring is in contact with the outer end face of the second tooth of the locking piece to position the locking piece axially and prevent the locking piece from coming out. At the same time, since the spiral retaining ring is arranged in the clamping groove inside the anti-rotation sleeve, the arrangement of the spiral retaining ring also limits the axial movement of the anti-rotation sleeve.

[0024] (3) In the present invention, the locking piece has a cylindrical structure and does not need to be bent or deformed before and after installation, can be reused, has low cost and good assembly performance; the cross-section of the anti-rotation sleeve passing through the central axis is L-shaped, the fitting surface of its fixed part is in contact with the end face of the locking nut, and the inside of the anti-rotation part is in contact with the locking piece. No bending is required during assembly and no plastic deformation will occur. Therefore, both the locking piece and the anti-rotation sleeve in the present invention can be reused and do not need to be used as consumables, reducing the production cost.

[0025] (4) In the present invention, the anti-rotation sleeve is fixed to the non-threaded section of the journal, and the locking piece is fitted into the non-threaded section of the locking nut. No grooves are provided in the threaded sections of the journal and the locking nut, avoiding weakening the strength of the thread.

[0026] (5) In the prior art, between the locking nut and the inner ring of the main bearing, in order to avoid damaging the inner ring of the main bearing, usually two methods are adopted: grinding the extrusion section of the nut or additionally adding a gasket. Grinding the nut will damage the surface structure of the nut, and frequent disassembly and assembly after using the gasket will cause fatigue failure, thus affecting the anti-loosening effect. In the present invention, the fixed part of the anti-rotation sleeve is arranged between the locking nut and the inner ring of the main bearing. On the one hand, it is used for fixing the anti-rotation sleeve; on the other hand, it avoids the grinding damage of the nut and the frictional damage to the end face of the inner ring of the main bearing caused by the tightening of the locking nut, and no additional gasket is needed. Moreover, the anti-rotation part and the fixed part of the anti-rotation sleeve are integrated, and the fixing of the fixed part to the journal further enhances the anti-loosening effect on the locking piece and the locking nut.

[0027] In the present invention, the above technical solutions can also be combined with each other to achieve more preferred combination schemes. Other features and advantages of the present invention will be described in the following content, and some advantages can be made obvious from the specification or understood by implementing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the content specifically pointed out in the text and the drawings. Description of the Drawings

[0028] The drawings are only for the purpose of showing specific embodiments and are not considered as a limitation to the present invention. Throughout the drawings, the same reference signs represent the same components.

[0029] Figure 1 It is a schematic external structure diagram of the anti-loosening structure of the locking nut of the main bearing for Embodiment 1;

[0030] Figure 2Structural diagram of the engagement between the notch of the anti-rotation sleeve and the second tooth of the lock piece in Embodiment 1;

[0031] Figure 3 Schematic structural diagram of the anti-loosening structure without the anti-rotation sleeve in Embodiment 1;

[0032] Figure 4 Schematic cross-sectional structural diagram of the anti-loosening structure in Embodiment 1;

[0033] Figure 5 Partial enlarged view of the engagement relationship between the anti-loosening structures in Embodiment 1;

[0034] Figure 6 Schematic structural diagram of the lock nut in Embodiment 1;

[0035] Figure 7 Schematic structural diagram of the anti-rotation sleeve in Embodiment 1;

[0036] Figure 8 Schematic structural diagram of the lock piece in Embodiment 1;

[0037] Figure 9 Flowchart of the anti-loosening method in Embodiment 3;

[0038] Figure 10 Schematic structural diagram of the journal and the main bearing assembly without the anti-loosening structure installed in Embodiment 3;

[0039] Figure 11 Schematic structural diagram after installing the anti-rotation sleeve in Embodiment 3;

[0040] Figure 12 Schematic structural diagram after installing the lock nut in Embodiment 3;

[0041] Figure 13 Schematic structural diagram after installing the lock piece in Embodiment 3;

[0042] Figure 14 Schematic structural diagram after installing the spiral retaining ring in Embodiment 3.

[0043] Reference numerals:

[0044] 1 - Journal, 11 - Threaded section, 12 - Non-threaded section, 121 - Second groove, 2 - Lock nut, 21 - Fixed section, 22 - Engaging section, 3 - Lock piece, 31 - Lock piece body, 32 - First tooth, 33 - Second tooth, 4 - Anti-rotation sleeve, 41 - Fixed part, 411 - Protrusion, 42 - Anti-rotation part, 421 - Notch, 422 - Card slot, 5 - Spiral retaining ring, 6 - Main bearing inner ring. Detailed implementation manners

[0045] The preferred embodiments of the present invention will be specifically described below in conjunction with the accompanying drawings. The accompanying drawings form a part of the present invention and are used together with the embodiments of the present invention to explain the principles of the present invention, rather than to limit the scope of the present invention.

[0046] Embodiment 1

[0047] A specific embodiment of the present invention, as Figures 1 - 5 shown, discloses a locking nut anti-loosening structure for a main bearing, including a locking nut 2, a lock washer 3, and an anti-rotation sleeve 4 sleeved on the journal 1 of the engine rotating shaft.

[0048] As Figure 6 shown, the locking nut 2 includes a fixed section 21 and an engaging section 22. As Figure 5 shown, the fixed section 21 is provided with an internal thread, which is connected to the external thread of the journal 1 to be fixed to the journal 1. For the convenience of installing anti-loosening components, the locking nut 2 is further provided with an engaging section 22. As Figure 3 shown, a plurality of first grooves are provided on the outer circumference of the engaging section 22. Exemplarily, the grooves in this embodiment are grooves with a square cross-section and are evenly distributed along the circumference.

[0049] As Figure 7 shown, the lock washer 3 includes a lock washer body 31, a first tooth 32 provided at the rear end of the lock washer body 31, and a second tooth 33 provided at the front end of the lock washer body 31.

[0050] The lock washer body 31 is cylindrical.

[0051] The first tooth 32 is an extension extending outward along the axis from the circumferential edge of the rear end face of the lock washer body 31. Exemplarily, the first teeth 32 are evenly distributed along the circumferential edge of the rear end face of the lock washer body 31. The first teeth 32 are embedded in the first grooves to limit the circumferential movement of the engaging section 22 of the locking nut 2.

[0052] In this embodiment, the first teeth 32 of the lock washer body 31 are engaged with the first grooves of the engaging section 22 to circumferentially limit the fixed section 21 of the locking nut 2, preventing the thread from loosening and failing under loads such as impact and vibration, and the nut from loosening.

[0053] The second tooth 33 is provided at the front end of the lock washer body 31 and extends radially outward from the circumferential edge of the front end face of the lock washer body 31. Exemplarily, the second teeth 33 are evenly distributed along the circumferential edge of the front end face of the lock washer body 31. The second teeth 33 are used to connect with the anti-rotation sleeve 4.

[0054] As Figure 5 and Figure 8As shown, the anti-rotation sleeve 4 has an L-shaped cross-section passing through its central axis. The anti-rotation sleeve 4 includes a fixing portion 41 and an anti-rotation portion 42. The anti-rotation portion 42 is sleeved outside the lock piece body 31, and the fixing portion 41 is perpendicular to its axis.

[0055] A part of the inner wall surface of the anti-rotation portion 42 is attached to the outer wall surfaces of the lock piece body 31 and the first tooth 32 to limit the circumferential movement of the lock piece 3; another part is attached to the outer wall surface of the locking nut 2 to further limit the circumferential movement of the locking nut 3. As Figure 2 and Figure 5 shown, the front end portion of the anti-rotation portion 42 has a notch 421 that engages with the second tooth 33. The second tooth 33 is inserted into the notch 421 and engages with the notch 421 to limit the circumferential movement of the lock piece 3 again. In this embodiment, by sleeving the anti-rotation portion 42 outside the fixed section 21 and the engagement of the end notch 421 of the anti-rotation portion 42 with the second tooth 33, the anti-loosening effect on the lock piece 3 is jointly achieved. At the same time, the engagement of the notch 421 with the second tooth 33 also limits the circumferential movement of the anti-rotation portion 42, and the anti-loosening of the anti-rotation sleeve 4 is synchronously achieved.

[0056] As Figure 4 and Figure 5 shown, the fixing portion 41 is connected to the journal 1, so that the anti-rotation sleeve 4 is fixed to the journal 1. A second groove 121 is provided on the journal 1, and the end edge of the fixing portion 41 is uniformly provided with protrusions 411 along the circumferential direction. As Figure 5 shown, the protrusions 411 extend radially inward for being clamped into the second groove 121 of the journal 1.

[0057] The fixing portion 41 is arranged between the locking nut 2 and the inner ring 6 of the main bearing. The fixing portion 41 includes a first fitting surface and a second fitting surface; the first fitting surface is in contact with the inner end surface of the locking nut 2, and the second fitting surface is in contact with the end surface of the inner ring 6 of the main bearing.

[0058] In the prior art, between the locking nut 2 and the inner ring 6 of the main bearing, in order to avoid damaging the inner ring 6 of the main bearing, usually two methods are adopted: grinding the extrusion section of the locking nut 2 or adding a gasket. Grinding the locking nut 2 will damage the surface structure of the locking nut 2, and frequent disassembly and assembly after using the gasket will cause fatigue failure, thus affecting the anti-loosening effect. In this embodiment, the fixing portion 41 of the anti-rotation sleeve 4 is arranged between the locking nut 2 and the inner ring 6 of the main bearing. On the one hand, it is used for fixing the anti-rotation sleeve 4. On the other hand, it avoids the grinding damage of the locking nut 2 and the frictional damage to the end surface of the inner ring 6 of the main bearing caused by the tightening of the locking nut 2. There is no need to add a gasket additionally, and the anti-rotation portion 42 and the fixing portion 41 of the anti-rotation sleeve 4 are integrated. The fixing of the fixing portion 41 to the journal 1 further enhances the anti-loosening effect on the lock piece 3 and the locking nut 2.

[0059] Further, it further includes a spiral retaining ring 5. AsFigure 5 As shown, a clamping groove 422 is provided inside the anti-rotation part 42 near the notch 421, and the outer edge of the spiral retaining ring 5 abuts against the bottom surface of the clamping groove 422. Under the action of its own radial elastic force and centrifugal force tension, the spiral retaining ring 5 closely adheres to the inner wall of the clamping groove 422 to prevent falling off. The inner end surface of the spiral retaining ring 5 fits with the outer end surface of the second tooth 33.

[0060] In this embodiment, a clamping groove is provided inside the anti-rotation sleeve 4 to engage the spiral retaining ring 5, position the lock piece 3 axially, and prevent the lock piece 3 from coming out; at the same time, since the spiral retaining ring 5 is arranged in the clamping groove 422 inside the anti-rotation sleeve 4, the arrangement of the spiral retaining ring 5 also limits the axial movement of the anti-rotation sleeve 4.

[0061] Compared with the prior art, in this embodiment, the first tooth 32 of the lock piece 3 is embedded in the first groove of the engaging section 22 of the locking nut 2, and the anti-rotation sleeve 4 is sleeved outside the locking nut 2 to limit the circumferential movement of the locking nut 2, jointly achieving anti-loosening of the locking nut 2; the fixing part 41 of the anti-rotation sleeve 4 is fixed to the journal 1, the anti-rotation part 42 is sleeved outside the lock piece 3, and the notch 421 at the end of the anti-rotation part 42 and the second tooth 33 of the lock piece 3 are mutually engaged to limit the circumferential movement of the lock piece 3, jointly achieving anti-loosening of the lock piece 3; the engagement of the notch 421 and the second tooth 33 also limits the circumferential movement of the anti-rotation part 42, synchronously achieving anti-loosening of the anti-rotation sleeve 4. This embodiment realizes anti-loosening for the locking nut 2, lock piece 3, and anti-rotation sleeve 4 in the anti-loosening structure, avoiding the anti-loosening failure caused by the deformation and falling off of the anti-loosening components when only anti-loosening the locking nut 2. The structure is simple and reliable, and the installation and disassembly are convenient.

[0062] In this embodiment, the lock piece 3 has a cylindrical structure and does not need to be bent and deformed before and after installation, can be reused, has low cost, and good assembly performance; the cross-section of the anti-rotation sleeve 4 passing through the central axis is L-shaped, the fitting surface of its fixing part 41 fits with the end surface of the locking nut 2, and the inside of the anti-rotation part 42 fits with the lock piece 3. No bending is required during assembly, and no plastic deformation will occur. Therefore, the lock piece 3 and the anti-rotation sleeve 4 in this embodiment can be reused and do not need to be used as consumables, reducing the production cost.

[0063] Embodiment 2

[0064] This embodiment discloses an aero-engine, including a rotating shaft, a main bearing assembly, and the anti-loosening structure of the main bearing locking nut in Embodiment 1.

[0065] The journal 1 of the rotating shaft includes a threaded section 11 and a non-threaded section 12. The threaded section 11 has an external thread, and the fixed section 21 of the locking nut 2 has an internal thread, and the internal thread is screwed with the external thread to fix the locking nut 2.

[0066] The main bearing assembly includes the main bearing inner ring 6. The fixing portion 41 of the anti-rotation sleeve 4 is disposed between the lock nut 2 and the main bearing inner ring 6.

[0067] The non-threaded section 12 of the rotating shaft is provided with a second groove 121, and the protrusion 411 of the fixing portion 41 of the anti-rotation sleeve 4 is engaged with the second groove 121 to fix the anti-rotation sleeve 4.

[0068] The anti-rotation sleeve 4 is fixed to the non-threaded section 12 of the journal 1, and the lock washer 3 is engaged with the non-threaded section 12 of the lock nut 2. No grooves are provided on the threaded sections 11 of the journal 1 and the lock nut 2, avoiding weakening the strength of the threads.

[0069] Compared with the prior art, the advantages of the aero-engine in this embodiment are the same as those of the anti-loosening structure of the main bearing lock nut 2 described above, and will not be elaborated here.

[0070] Embodiment 3

[0071] This embodiment provides a method for preventing loosening of the main bearing lock nut. As Figure 9 shown, based on the anti-loosening structure of the main bearing lock nut shown in Embodiment 1, it includes the following steps:

[0072] Step 1: Install the anti-rotation sleeve 4 and fix the anti-rotation sleeve 4 to the non-threaded section 12 of the journal 1;

[0073] Engage the protrusion 411 of the fixing portion 41 of the anti-rotation sleeve 4 with the second groove 121 of the journal 1, so that one end of the anti-rotation sleeve 4 is fixed to the non-threaded section 12 of the journal 1;

[0074] As Figure 10 shown is the journal 1 after installing the main bearing. As Figure 11 shown, install the anti-rotation sleeve 4 on the journal 1 of the main bearing; during installation, engage the protrusion 411 of the fixing portion 41 of the anti-rotation sleeve 4 with the second groove 121 of the non-threaded section 12 of the journal 1 to fix the anti-rotation sleeve 4. At the same time, separate the lock nut 2 and the main bearing inner ring 6 through the fixing portion 41 of the anti-rotation sleeve 4, avoiding the need to grind the extrusion section of the nut when the lock nut 2 directly contacts the bearing in the prior art, and also avoiding the fatigue failure of the gasket caused by adding an additional gasket during subsequent disassembly and assembly, thus affecting the anti-loosening effect. At the same time, the anti-rotation portion 42 and the fixing portion 41 of the anti-rotation sleeve 4 are integrated, and the fixing of the fixing portion 41 to the journal 1 further enhances the anti-loosening effect on the lock washer 3 and the lock nut 2.

[0075] Step 2: Install the lock nut 2 and screw the fixing section 21 of the lock nut 2 into the journal 1 and fix it;

[0076] Screw the fixing section 21 of the lock nut 2 into the threaded section 11 of the journal 1, and the engaging section 22 faces the side of the fixing portion 41 of the anti-rotation sleeve 4.

[0077] AsFigure 12 As shown in the figure, install the lock nut 2. During installation, the fixed section 21 of the lock nut 2 is screwed into the threaded section 11 of the journal 1, and the fitting section 22 faces the side of the fixing portion 41 of the anti-rotation sleeve 4. At this time, the end face of the fitting section 22 of the lock nut 2 fits the fixing portion 41, one side of the fixing portion 41 of the anti-rotation sleeve 4 fits the lock nut 2, and the other side fits the inner ring 6 of the main bearing, restricting the axial direction of the anti-rotation sleeve 4.

[0078] Step 3: Install the lock washer 3 to restrict the circumferential movement of the lock nut 2; and restrict the circumferential movement of the lock washer 3 and the anti-rotation sleeve 4.

[0079] Put the lock washer 3 outside the lock nut 2. The first tooth 32 engages with the first groove of the engaging section 22 of the lock nut 2 to restrict the circumferential movement of the lock nut 2; the second tooth 33 engages with the notch 421 of the anti-rotation sleeve 4 to restrict the circumferential movement of the lock washer 3 and the anti-rotation sleeve 4.

[0080] As Figure 13 shown in the figure, install the lock washer 3. During installation, put the lock washer 3 outside the lock nut 2. The first tooth 32 engages with the first groove of the engaging section 22 of the lock nut 2 to jointly restrict the circumferential movement of the lock nut 2, achieving the anti-loosening effect of the lock nut; the second tooth 33 engages with the notch 421 of the anti-rotation sleeve 4 to restrict the circumferential movement of the lock washer 3 and the anti-rotation sleeve 4. At the same time, the lock washer 3 is installed inside the anti-rotation sleeve 4 and closely adheres to the inner wall of the anti-rotation sleeve 4, achieving the anti-loosening effect of the lock washer 3 and the anti-rotation sleeve 4.

[0081] Step 4: Install the snap ring 5 of the anti-loosening structure of the main bearing lock nut to restrict the axial movement of the anti-rotation sleeve 4 and the lock washer 3, and complete the anti-loosening of the lock nut, lock washer and anti-rotation sleeve.

[0082] The snap ring 5 is snapped into the front-end slot 412 of the anti-rotation sleeve 4. The inner end face of the snap ring 5 fits the outer end face of the second tooth 33 to restrict the axial movement of the anti-rotation sleeve 4 and the lock washer 3.

[0083] As Figure 14 shown in the figure, install the snap ring 5. Snap the snap ring 5 into the front-end slot 412 of the anti-rotation sleeve 4. The inner end face of the snap ring 5 fits the outer end face of the second tooth 33 to restrict the axial movement of the anti-rotation sleeve 4 and the lock washer 3.

[0084] It should be noted that the snap ring 5 is made of elastic material and can closely adhere to the inner wall of the slot 422 under the action of its own radial elastic force and centrifugal force tension to prevent falling off.

[0085] As described above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A main bearing locking nut anti-loosening structure, characterized in that: It comprises a locking nut (2), a locking plate (3) and an anti-rotation sleeve (4) which are sleeved on the outside of a journal (1) of an engine shaft; The locking nut (2) comprises a fixing section (21) and a clamping section (22); the fixing section (21) is fixed to the shaft neck (1), and a first groove is provided on the outer circumference of the clamping section (22); The locking plate (3) comprises a locking plate body (31), a first tooth (32) and a second tooth (33); the first tooth (32) is embedded in the first groove, and the first tooth (32) limits the circumferential movement of the locking nut (2); The anti-rotation sleeve (4) comprises a fixing portion (41) and an anti-rotation portion (42); the fixing portion (41) is connected to the shaft neck (1); the inner wall surface of the anti-rotation portion (42) is attached to the outer wall surfaces of the locking nut (2) and the locking plate (3); and the end of the anti-rotation portion (42) has a notch (421) that engages with the second tooth (33).

2. The main bearing locking nut anti-loosening structure according to claim 1, characterized in that: It also comprises a spiral retaining ring (5); a retaining groove (422) is provided inside the anti-rotation portion (42) near the notch (421); the outer edge of the spiral retaining ring (5) abuts against the bottom surface of the retaining groove (422); and the inner end surface of the spiral retaining ring (5) fits against the outer end surface of the second tooth (33).

3. The main bearing locking nut anti-loosening structure according to claim 1, characterized in that: The locking piece body (31) is cylindrical.

4. The main bearing locking nut anti-loosening structure according to claim 3 is characterized in that: The first teeth (32) are evenly arranged at the rear end of the locking plate body (31) along the circumferential direction, and the first teeth (32) extend outward from the circumferential edge of the rear end surface of the locking plate body (31) along its axial direction; the first teeth (32) are engaged with the first groove.

5. The main bearing locking nut anti-loosening structure according to claim 3, characterized in that: The second teeth (33) are evenly arranged at the front end of the locking plate body (31) along the circumferential direction, and the second teeth (33) extend radially outward from the circumferential edge of the front end surface of the locking plate body (31).

6. An aircraft engine, characterized in that: The invention comprises a rotating shaft, a main bearing assembly and a main bearing locking nut anti-loosening structure as described in any one of claims 1 to 5.

7. The aircraft engine according to claim 6, characterized in that: The shaft neck (1) of the rotating shaft comprises a threaded section (11) and a non-threaded section (12); the threaded section (11) has an external thread, and the fixing section (21) of the locking nut (2) has an internal thread, and the internal thread is screwed to the external thread.

8. The aircraft engine according to claim 7, characterized in that: The main bearing assembly comprises a main bearing inner ring (6); the fixing portion (41) is arranged between the locking nut (2) and the main bearing inner ring (6).

9. The aircraft engine according to claim 8, characterized in that: The fixing portion (41) comprises a first fitting surface and a second fitting surface; The first fitting surface fits with the inner end surface of the locking nut (2), and the second fitting surface fits with the end surface of the main bearing inner ring (6).

10. The aircraft engine according to claim 8, characterized in that: The end edge of the fixing portion (41) is evenly provided with protrusions (411) along the circumferential direction, and the protrusions (411) extend radially inward; The non-threaded section (12) of the rotating shaft is provided with a second groove (121); the protrusion (411) is engaged with the second groove (121).

Images