Combination fastener surface covering system and method of using same

Abstract

The invention discloses a combined fastener surface covering system and a using method thereof, belongs to the technical field of fastener application, and aims to solve the problem that the height difference exists at the head of a fastener on the surface of an existing airplane, the combined fastener surface covering system comprises a center cover (1) and a ring (2), the center cover (1) can be separated from the ring (2), and the center cover (1) can be separated from the ring (2). The outer surface of the center cover (1) comprises a first connecting section (11) and a second connecting section (12), the first connecting section (11) of the center cover (1) can be inserted into a wrenching groove (31) of the bolt (3) in a matched mode, and the inner end face (21) of the ring can be completely attached to the outer end face (32) of the head of the bolt. According to the combined fastener surface covering system, the head of the fastener can be flush with a paint layer on the surface of a machine body, the overall flatness and aerodynamic performance of the surface of the machine body are improved, meanwhile, the surface of the head of the fastener is systematically covered, and secondary scattering generated due to exposure of the fastener is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of fastener applications, specifically to a combined fastener surface covering system and a method for using the combined fastener surface covering system. Background Art

[0002] The countersunk fasteners on the surface of the aircraft fuselage are the most secondary scatter sources on modern aircraft. Such scatter sources are large in number, irregularly distributed, and have strong scattering properties. The current slot cover products only supplement the wrenching slot part of the fastener, but do not systematically cover the head of the fastener, and cannot solve the scattering problem. At the same time, when the whole fuselage is painted, the head of the fastener is often avoided to prevent the coating from peeling off due to the disassembly of the fastener. Therefore, there is a certain height difference between the surface of the fastener head and the fuselage paint, which affects the flatness and aerodynamic performance of the whole machine. Summary of the Invention

[0003] In order to solve the problem of the height difference at the head of the fastener on the existing aircraft surface, the present invention provides a combined fastener surface covering system and a method for using the same. The combined fastener surface covering system can make the head of the fastener flush with the paint layer on the fuselage surface, improve the overall flatness and aerodynamic performance of the fuselage surface, and at the same time systematically cover the surface of the fastener head to reduce the secondary scattering caused by the exposure of the fastener.

[0004] The technical solution adopted by the embodiments of the present invention to solve its technical problems is as follows:

[0005] A combined fastener surface covering system includes a center cover and a ring. The center cover can be detached from the ring. The outer surface of the center cover contains a first connection section and a second connection section arranged axially in sequence. When the first connection section of the center cover is inserted into the wrenching slot of the bolt in a matching manner and the inner end face of the ring is completely attached to the outer end face of the bolt head, the second connection section is sleeved in the ring in a matching manner, and the outer end face of the center cover is flush with the outer end face of the ring.

[0006] A method for using a combined fastener surface covering system adopts the above-mentioned combined fastener surface covering system. The method for using the combined fastener surface covering system includes the installation methods of the center cover, the ring, and the bolt. The installation methods of the center cover, the ring, and the bolt include the following steps in sequence:

[0007] 1a. Install the ring

[0008] Completely attach the inner end face of the ring to the outer end face of the bolt head;

[0009] 2a. Install the center cover

[0010] Insert the first connecting section of the central cover into the wrenching groove of the bolt in a matching manner, and install the bolt into the bolt hole of the aircraft skin.

[0011] 3a. Paint coating

[0012] Apply paint coating on the outer surface of the aircraft skin to form a surface coating layer, and the outer surface of the surface coating layer, the outer end face of the ring and the outer end face of the central cover are flush.

[0013] The beneficial effects of the embodiments of the present invention are as follows: systematically cover the entire head of the fastener on the aircraft skin surface, reduce the height difference between the paint on the airframe surface and the fastener surface, make the fuselage surface more flat, thus solving the overall flatness problem of the paint-fastener-wrenching groove system, improving the aerodynamic performance of the whole aircraft, and reducing the secondary scattering caused by the exposure of the fasteners. Description of the drawings

[0014] The specification drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0015] Figure 1 It is a front view schematic diagram of the central cover.

[0016] Figure 2 It is a top view schematic diagram of the central cover.

[0017] Figure 3 It is along Figure 2 The sectional view schematic diagram in the A-A direction in

[0018] Figure 4 It is a front view schematic diagram of the ring.

[0019] Figure 5 It is a top view schematic diagram of the ring.

[0020] Figure 6 It is along Figure 5 The sectional view schematic diagram in the B-B direction in

[0021] Figure 7 It is a schematic diagram of the bolt.

[0022] Figure 8 It is a schematic diagram of the connection between the ring and the bolt.

[0023] Figure 9 It is a schematic diagram of installing the central cover, the ring and the bolt on the aircraft skin.

[0024] Figure 10 It is a schematic diagram after applying paint coating on the outer surface of the aircraft skin.

[0025] Figure 11It is a schematic diagram after removing the groove cover and bolts on the aircraft skin.

[0026] The descriptions of the reference numerals are as follows:

[0027] 1. Central cover; 2. Ring; 3. Bolt; 4. Aircraft skin; 5. Surface coating layer;

[0028] 11. First connection section; 12. Second connection section; 13. Outer end face of the central cover; 14. Inner groove; 15. Inner end face of the central cover;

[0029] 21. Inner end face of the ring; 22. Outer end face of the ring;

[0030] 31. Wrenching groove; 32. Outer end face of the bolt head;

[0031] 41. Bolt hole. Specific implementation manners

[0032] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0033] As Figures 1 to 6 shown, a combined fastener surface covering system (or can also be called a fastener surface covering assembly) described in an embodiment of the present invention includes an independent central cover 1 and a ring 2. The central cover 1 can be separated from the ring 2. The central cover 1 is generally in a cylindrical structure. The outer surface of the central cover 1 contains a first connection section 11 and a second connection section 12 arranged in sequence along the axial direction of the central cover 1. When the first connection section 11 of the central cover 1 is inserted into the wrenching groove 31 of the bolt 3 in a matching manner and the inner end face 21 of the ring is completely attached to the outer end face 32 of the bolt head, the second connection section 12 is sleeved in the ring 2 in a matching manner, and the outer end face 13 of the central cover is flush with the outer end face 22 of the ring (located in the same plane, arc surface or spherical surface).

[0034] The central cover 1 and the ring 2 can systematically cover the head of the bolt 3 on the surface of the aircraft skin as a whole, reduce the height difference between the surface of the paint coated on the body surface and the outside of the head of the bolt 3, make the fuselage surface smoother, thereby solving the overall flatness problem of the paint-fastener-wrenching groove system, improving the aerodynamic performance of the whole machine, and reducing the secondary scattering caused by the exposure of the fasteners.

[0035] As Figures 1 to 3 shown, the axis of the central cover 1, the axis of the first connection section 11, and the axis of the second connection section 12 coincide. The cross-section of the outer peripheral surface of the first connection section 11 is in an external gear shape structure. The outer peripheral surface of the second connection section 12 is a cylindrical outer peripheral surface. The cross-section of the inner peripheral surface of the wrenching groove 31 is in an internal gear shape structure. The first connection section 11 and the wrenching groove 31 of the bolt 3 can be in an interference fit.

[0036] Specifically, the cross-section of the outer peripheral surface of the first connecting section 11 has an external hexagonal gear-shaped structure, and the cross-section of the inner peripheral surface of the wrenching groove 31 has an internal hexagonal gear-shaped structure. The cross-section of the outer peripheral surface of the first connecting section 11 can completely coincide with the cross-section of the inner peripheral surface of the wrenching groove 31. When the first connecting section 11 of the central cover 1 is inserted into the wrenching groove 31 of the bolt 3 in a matching manner, the first connecting section 11 and the wrenching groove 31 of the bolt 3 are in interference fit.

[0037] The central cover 1 is used to shield the wrenching groove 31. An inner groove 14 is provided at the inner end of the central cover 1. The provision of the inner groove 14 facilitates disassembly. The maximum diameter of the first connecting section 11 is the same as the diameter of the second connecting section 12. When the first connecting section 11 of the central cover 1 is inserted into the wrenching groove 31 of the bolt 3 in a matching manner, the axis of the central cover 1, the axis of the ring 2, and the axis of the bolt 3 coincide, and the inner end face 15 of the central cover abuts against the bottom end face of the wrenching groove 31.

[0038] As Figures 4 to 6 shown, the outer diameter of the ring 2 is equal to the outer diameter of the outer end face 32 of the bolt head, the inner diameter of the ring 2 is equal to the outer diameter of the second connecting section 12, and the inner diameter of the ring 2 is equal to the maximum diameter of the inner peripheral surface of the wrenching groove 31. When the ring 2 is stacked and connected to the outer end face 32 of the bolt head, the axis of the ring 2 coincides with the axis of the bolt 3, the outer edge of the inner end face 21 of the ring coincides with the outer edge of the outer end face 32 of the bolt head, and the inner edge of the inner end face 21 of the ring coincides with the inner edge of the outer end face 32 of the bolt head.

[0039] In this embodiment, the ring 2 is used to cover the outer end face 32 part of the bolt head and also to improve the surface flatness. The thickness h of the ring 2 is the same as the thickness h of the second connecting section 12. The thickness of the ring 2 is the same as the thickness of the surface coating layer 5 outside the aircraft skin 4. The material of the ring 2 is the same as the material of the central cover 1. The performance of the ring 2 and the performance of the central cover 1 are substantially the same as the performance of the surface coating layer 5, which can ensure the overall flatness and electrical continuity after covering, thereby enhancing the concealment.

[0040] As Figure 10 shown, when the first connecting section 11 of the central cover 1 is inserted into the wrenching groove 31 of the bolt 3 in a matching manner, the inner edge of the second connecting section 12 is flush with the outer end face 32 of the bolt head, and the outer surface of the surface coating layer 5, the outer end face 22 of the ring, and the outer end face 13 of the central cover are substantially flush.

[0041] The inner end face 21 of the ring is adhesively fixed to the outer end face 32 of the bolt head. The roughness of the inner end face 21 of the ring is greater than that of the outer end face 22 of the ring, which is conducive to the adhesion of the adhesive, enabling the firm adhesion between the inner end face 21 of the ring and the outer end face 32 of the bolt head. The roughness of the outer end face 22 of the ring is equal to that of the outer surface of the surface coating layer 5.

[0042] The following introduces a usage method of the surface covering system for the combined fastener. The usage method of the surface covering system for the combined fastener adopts the above-mentioned surface covering system for the combined fastener. The usage method of the surface covering system (and the bolt 3) includes the installation methods of the center cap 1, the ring 2, and the bolt 3. The installation methods of the center cap 1, the ring 2, and the bolt 3 successively include the following steps:

[0043] 1a. Install the ring 2

[0044] As Figures 7 to 8 shown, use sandpaper or a grinding disc to polish the outer end face 32 of the bolt head to be assembled. In addition to removing the dust on the outer end face 32 of the bolt head and improving its flatness, it is also conducive to the adhesion of the binder, preparing for the bonding of the ring 2. Completely fit the inner end face 21 of the ring with the outer end face 32 of the bolt head through the adhesive. This connection is a permanent connection, and the ring 2 is not disassembled unless necessary; the axis of the ring 2 coincides with the axis of the bolt 3, the outer edge of the inner end face 21 of the ring coincides with the outer edge of the outer end face 32 of the bolt head, and the inner edge of the inner end face 21 of the ring coincides with the inner edge of the outer end face 32 of the bolt head.

[0045] 2a. Install the center cap 1

[0046] As Figure 9 shown, after the ring 2 is adhesively bonded to the head surface of the bolt 3, it does not affect the exposure of the wrenching groove 31 of the bolt 3. Insert the first connection section 11 of the center cap 1 into the wrenching groove 31 of the bolt 3 in a matching manner, and install the bolt 3 into the bolt hole 41 of the aircraft skin 4; complete the blocking of the wrenching groove 31 and the covering of the exposed metal on the head surface of the bolt 3. The thickness h of the ring 2 and the thickness h of the second connection section 12 can be adjusted as needed, and different thicknesses of the surface coating layer 5 can be adapted. For example, adjusting the thickness h of the ring 2 and the thickness h of the second connection section 12 can be achieved by adjusting the die size during the processing. Fine-tune the die according to the thickness of different surface coating layers 5; also, according to the roughness of the outer surface of the surface coating layer 5, select appropriate sandpaper to polish the outer end face 22 of the ring and the outer end face 13 of the center cap without affecting its service performance.

[0047] 3a. Paint coating

[0048] As Figure 10As shown, a paint coating is applied to the outer surface of the aircraft skin 4 to form a surface coating layer 5. When applying the paint coating, the outer end face 22 of the ring and the outer end face 13 of the center cover should be avoided. Finally, the outer surface of the surface coating layer 5, the outer end face 22 of the ring, and the outer end face 13 of the center cover are flush.

[0049] The method of using the combined fastener surface covering system (and the bolt 3) further includes the method of disassembling the center cover 1, the ring 2, and the bolt 3. The method of disassembling the center cover 1, the ring 2, and the bolt 3 successively includes the following steps:

[0050] 1b. Disassemble the center cover 1

[0051] As Figure 11 shown, separate the center cover 1 from the ring 2 and the bolt 3. After screwing in a self-tapping screw or other tool into the center cover 1, pull out the center cover 1 and the self-tapping screw together. The center cover 1 is for single use. The outer end face 13 of the center cover is flat without notches, and there is no axial inner through hole in the center cover 1, minimizing the appearance frequency of "holes" and "seams" on the aircraft skin surface and improving the flatness and aerodynamic performance. After removing the center cover 1 first, the wrenching groove 31 can be exposed;

[0052] 2b. Disassemble the bolt 3

[0053] Unscrew the bolt 3 from the bolt hole 41 of the aircraft skin 4. During this process, the ring 2 will always remain fixed on the outer end face 32 of the bolt head and be disassembled and assembled together with the bolt 3. The ring 2 is not disassembled unless necessary. The ring 2 can be disassembled and assembled with the bolt 3 without affecting the disassembly and assembly process of the bolt 3. If the bolt 3 is replaced, reinstall the ring 2.

[0054] Using this disassembly method, the bolt 3 can be disassembled without damaging the paint surface, ensuring the integrity of the paint surface.

[0055] As mentioned above, only the specific embodiments of the present invention are described, and the scope of the invention implementation cannot be limited by them. Therefore, the replacement of equivalent components or the equivalent changes and modifications made according to the protection scope of the present invention should still fall within the scope covered by the present invention. In addition, the technical features in the present invention, between technical features, between technical features and technical solutions, between technical solutions, and between embodiments can be freely combined and used.

Claims

1. A combined fastener surface covering system, characterized in that, The combined fastener surface covering system includes a center cap (1) and a ring (2). The center cap (1) can be separated from the ring (2). The outer surface of the center cap (1) contains a first connecting section (11) and a second connecting section (12) arranged axially in sequence. When the first connecting section (11) of the center cap (1) is inserted into the wrenching groove (31) of the bolt (3) in a matching manner and the inner end face (21) of the ring is completely attached to the outer end face (32) of the bolt head, the second connecting section (12) is sleeved in the ring (2) in a matching manner, and the outer end face (13) of the center cap is flush with the outer end face (22) of the ring.

2. The combined fastener surface covering system according to claim 1, characterized in that, The cross-section of the outer peripheral surface of the first connecting section (11) has an external gear-shaped structure. The outer peripheral surface of the second connecting section (12) is a cylindrical outer peripheral surface. The cross-section of the inner peripheral surface of the wrenching groove (31) has an internal gear-shaped structure. The first connecting section (11) and the wrenching groove (31) of the bolt (3) can be in interference fit.

3. The combined fastener surface covering system according to claim 2, characterized in that, An inner groove (14) is provided at the inner end of the center cap (1). The maximum diameter of the first connecting section (11) is the same as the diameter of the second connecting section (12).

4. The combined fastener surface covering system according to claim 1, characterized in that, When the first connecting section (11) of the center cap (1) is inserted into the wrenching groove (31) of the bolt (3) in a matching manner, the inner end face (15) of the center cap abuts against the wrenching groove (31).

5. The combined fastener surface covering system according to claim 1, characterized in that, The outer diameter of the ring (2) is equal to the outer diameter of the outer end face (32) of the bolt head. When the ring (2) is stacked and connected to the outer end face (32) of the bolt head, the axis of the ring (2) coincides with the axis of the bolt (3).

6. The combined fastener surface covering system according to claim 5, characterized in that, The inner diameter of the ring (2) is equal to the outer diameter of the second connecting section (12). The inner diameter of the ring (2) is equal to the maximum diameter of the inner peripheral surface of the wrenching groove (31).

7. The combined fastener surface covering system according to claim 1, characterized in that, The thickness of the ring (2) is the same as the thickness of the second connecting section (12). The material of the ring (2) is the same as the material of the center cap (1). The thickness of the ring (2) is the same as the thickness of the surface coating layer (5) outside the aircraft skin (4).

8. The combined fastener surface covering system according to claim 7, characterized in that, The roughness of the inner end face (21) of the ring is greater than the roughness of the outer end face (22) of the ring. The roughness of the outer end face (22) of the ring is equal to the roughness of the outer surface of the surface coating layer (5).

9. A method for using a combined fastener surface covering system, characterized in that, The usage method of the combined fastener surface covering system adopts the combined fastener surface covering system described in claim 1. The usage method of the combined fastener surface covering system includes the installation methods of the center cap (1), the ring (2) and the bolt (3). The installation methods of the center cap (1), the ring (2) and the bolt (3) include the following steps in sequence: 1a. Install the ring (2) Completely attach the inner end face (21) of the ring to the outer end face (32) of the bolt head; 2a. Install the center cap (1) Insert the first connecting section (11) of the center cap (1) into the wrenching groove (31) of the bolt (3) in a matching manner, and install the bolt (3) into the bolt hole (41) of the aircraft skin (4); 3a. Paint coating Perform paint coating on the outer surface of the aircraft skin (4) to form a surface coating layer (5). The outer surface of the surface coating layer (5), the outer end face (22) of the ring and the outer end face (13) of the center cap are flush.

10. The method for using a combined fastener surface covering system according to claim 9, characterized in that, The usage method of the combined fastener surface covering system further includes the disassembly methods of the center cover (1), the ring (2) and the bolt (3). The disassembly methods of the center cover (1), the ring (2) and the bolt (3) successively include the following steps: 1b. Disassemble the center cover (1) Separate the center cover (1) from the ring (2) and the bolt (3); 2b. Disassemble the bolt (3) Unscrew the bolt (3) from the bolt hole (41) of the aircraft skin (4).

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