Helicopter rain sealing opening cover

Abstract

The invention provides a helicopter rain sealing covering cap which comprises a covering cap assembly, a skin, a reinforcing structure, a sealing assembly, a supporting assembly and a locking mechanism, and the reinforcing structure comprises an upper longitudinal horizontal piece, a lower longitudinal horizontal piece, a front frame, a rear frame and a reinforcing plate; the sealing assembly comprises a sealing baffle, a sealing rubber strip and a flow guide groove. The upper longitudinal horizontal piece, the lower longitudinal horizontal piece, the front frame and the rear frame are all of a long plate frame structure, and in order to prevent local instability caused by compression, the width-to-thickness ratio of the inner edge strip is smaller than 12; the upper longitudinal horizontal piece, the lower longitudinal horizontal piece, the front frame and the rear frame are mounted on the inner side of the skin through rivet connection; the edge strip and the web plate at the junction of the upper longitudinal horizontal piece and the front frame and the rear frame are disconnected, and the edge strip and the web plate at the junction of the lower longitudinal horizontal piece and the front frame and the rear frame are disconnected.

Description

Technical Field

[0001] The invention relates to the field of helicopter structure design, in particular to a helicopter rain sealing cover. Background Art

[0002] In the process of helicopter design, in order to facilitate the inspection and maintenance of many onboard equipment and key structures of the fuselage, it is usually necessary to provide inspection and maintenance channels for these onboard equipment and key structures by opening them on the fuselage skin. In addition, in order to ensure the integrity of the helicopter's aerodynamic shape during operation and the rain-proof properties of the skin structure to the internal structure of the fuselage, cover structures are usually designed at the positions of these openings.

[0003] However, the existing flap design needs to solve the following three problems:

[0004] a. The rainproof sealing performance of the cover is poor;

[0005] b. The opening and closing of the flap is inconvenient;

[0006] The safety and reliability of the cover being kept open and closed are poor. Summary of the invention

[0007] In order to solve the above problems, the present invention provides a helicopter rain sealing cover design method that meets the requirements of rain sealing, maintainability and reliability, aiming at the main structure of the helicopter rain sealing cover, so that the equipment in the helicopter cabin can be better sealed from the rain while having better inspection and maintenance channels.

[0008] Technical solution: A helicopter rain sealing cover, the cover comprises a cover assembly 1, a skin 2, a reinforcement structure, a sealing assembly, a support assembly 9, and a locking mechanism 10, wherein:

[0009] The reinforcement structure includes adding an upper longitudinal horizontal member 3, a lower longitudinal horizontal member 4, a front frame 5, a rear frame 6 and a reinforcement plate 7; the sealing assembly includes a sealing baffle 13, a sealing strip 14, and a guide groove 15; the upper longitudinal horizontal member 3, the lower longitudinal horizontal member 4, the front frame 5 and the rear frame 6 are all long plate frame structures, and in order to prevent local instability due to compression, the width-to-thickness ratio of the inner edge strip is less than 12; the upper longitudinal horizontal member 3, the lower longitudinal horizontal member 4, the front frame 5 and the rear frame 6 are installed on the inner side of the skin 2 by rivet connection; the edge strip and the web at the intersection of the upper longitudinal horizontal member 3 and the front frame 5 and the rear frame 6 are disconnected, and the edge strip and the web at the intersection of the lower longitudinal horizontal member 4 and the front frame 5 and the rear frame 6 are disconnected, and the web is connected to the front frame 5 and the rear frame 6 by bending. The plate is installed by rivet connection, and the reinforcing plate 7 is placed between the edge strips of the upper longitudinal horizontal member 3, the lower longitudinal horizontal member 4, the front frame 5 and the rear frame 6 and the skin 1, and is installed by rivet connection; if it can be achieved that the gas elastic force extension line of the gas elastic strut in the closed state is on the inner side of the rotation center of the hinge 10, the gas elastic strut is selected as the supporting structure 9; in the open state, the gas elastic strut is arranged so that the gas elastic force extension line is on the outer side of the rotation center of the hinge 10, and the gas elastic force of the supporting structure 9 is greater than 1.5 times the sum of the closing force in the direction of the gas elastic strut generated by the deadweight of the flap and the additional load in the use scenario; in the closed state, the gas elastic force extension line of the supporting structure 9 is on the inner side of the rotation center of the hinge, thereby forming a locking force for closing the flap.

[0010] Specifically, the opening of skin 2 is thickened, and the thickening size of skin 2 is determined according to the average shear flow to ensure that the shear stress of skin 2 after thickening is less than the allowable stress of the material. Usually, the thickness of skin 2 at the opening is 1.2 to 1.5 times the thickness of the skin in other areas without openings.

[0011] Specifically, the sealing surface 12 is a physical separation surface that has a shower sealing effect between the movable cover and the fixed body structure 15 in the locked state; for a rain shower sealing structure containing a sealing baffle 13 component that does not deform significantly under pressure, the sealing surface refers to the action surface between the sealing baffle 13 and the sealing strip 14 fixed on the body structure 11.

[0012] Specifically, the surface normal N at any point P2 on the sealing surface and the movement direction of the corresponding closing point P1 on the middle cover when closed The resulting ∠α ranges from 0° to 10°.

[0013] Specifically, the sealing surface 12 is a sealing surface formed by the sealing baffle 13 squeezing the sealing strip 14 and deforming it in the locked state.

[0014] Specifically, the flap assembly 1 is connected to the body by a hinge 10, and a locking mechanism 8 is used to fix the flap assembly 1. The locking force of the locking mechanism 8 is greater than 1.5 times the connection strength.

[0015] Specifically, the types of the support structure 9 include gas-elastic struts and mechanical struts.

[0016] Specifically, if it is not possible to ensure that the gas elastic force extension line of the gas elastic strut is inside the rotation center of the hinge 10 in the closed state, a mechanical strut is selected as the supporting structure.

[0017] In summary, the present application provides a helicopter rain seal cover for helicopter rain seal cover scheme design, which has comprehensive elements and strong applicability and can be widely used in helicopter cover scheme design. It is comprehensive and covers conventional design requirements such as cover rain seal, maintainability, and reliability design; the design constraints of the sealing components and support structures are converted into geometric parameter design, and the design accuracy is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the main structure of the helicopter rain sealing cover.

[0019] Figure 2 Schematic diagram of the sealing surface design.

[0020] Figure 3 Schematic diagram of the design of the sealing component.

[0021] Figure 4 Schematic diagram for selecting mounting points for the gas struts.

[0022] Among them, 1 - cover assembly, 2 - skin, 3 - upper longitudinal horizontal member, 4 - lower longitudinal horizontal member, 5 - front frame, 6 - rear frame, 7 - reinforcement plate, 8 - locking mechanism, 9 - support structure, 10 - hinge, 11 - body structure, 12 - sealing surface, 13 - sealing baffle, 14 - sealing strip, 15 - guide groove. DETAILED DESCRIPTION

[0024] In order to solve these problems, targeted designs should be carried out during the cover design process so that the helicopter cover has better rain sealing properties, is easy and quick to open and close, and remains open and closed safely and reliably.

[0025] like Figure 1 As shown, the present application provides a helicopter rain sealing cover comprising: a cover assembly 1, a skin 2, a reinforcement structure, a sealing assembly, a support assembly 9, and a locking mechanism 10, wherein:

[0026] The reinforcement structure includes adding an upper longitudinal horizontal member 3, a lower longitudinal horizontal member 4, a front frame 5, a rear frame 6 and a reinforcement plate 7; the sealing assembly includes a sealing baffle 13, a sealing rubber strip 14, and a guide groove 15; the upper longitudinal horizontal member 3, the lower longitudinal horizontal member 4, the front frame 5 and the rear frame 6 are all long plate-frame structures with a height of about 100 mm. In order to prevent local instability due to compression, the width-to-thickness ratio of the inner edge strip is less than 12. The upper longitudinal horizontal member 3, the lower longitudinal horizontal member 4, the front frame 5 and the rear frame 6 are installed on the inner side of the skin 2 by rivet connection. The edge strip and the web plate at the intersection of the upper longitudinal horizontal member 3 and the front frame 5 and the rear frame 6 are disconnected, and the edge strip and the web plate at the intersection of the lower longitudinal horizontal member 4 and the front frame 5 and the rear frame 6 are disconnected. The web plate is installed by rivet connection with the web plate of the front frame 5 and the rear frame 6 by bending, and the reinforcement plate 7 is placed between the edge strips of the upper longitudinal horizontal member 3, the lower longitudinal horizontal member 4, the front frame 5 and the rear frame 6 and the skin 1, and is installed by rivet connection.

[0027] Specifically, the opening of skin 2 is thickened, and the thickening size of skin 2 is determined according to the average shear flow to ensure that the shear stress of skin 2 after thickening is less than the allowable stress of the material. Usually, the thickness of skin 2 at the opening is 1.2 to 1.5 times the thickness of the skin in other areas without openings, and the thickening width is 100 mm.

[0028] In practical applications, the outline of the cover assembly 1 is as regular as possible, preferably square and round. The size of the cover assembly 1 is determined according to the size of the installation and maintenance channel of the equipment, and the opening size is the minimum value that meets all requirements.

[0029] Specifically, the sealing surface 12 is a physical separation surface that has a shower sealing effect between the movable cover and the fixed body structure 15 in the locked state; for a rain shower sealing structure containing a sealing baffle 13 component that does not deform significantly under pressure, the sealing surface refers to the action surface between the sealing baffle 13 and the sealing strip 14 fixed on the body structure 11.

[0030] Specifically, the surface normal N at any point P2 on the sealing surface and the movement direction of the corresponding closing point P1 on the middle cover when closed The resulting ∠α ranges from 0° to 10°.

[0031] In practical applications, the specific shape of the sealing surface 12 is usually affected by a combination of factors such as the shape of the skin 2 where the flap assembly 1 is located, the outer dimensions of the flap assembly 1 , and the bearing capacity of other structures around the flap assembly 1 .

[0032] The sealing assembly is used to prevent rainwater outside the cabin from entering the cabin. The accumulated liquid blocked around the sealing surface 12 can quickly flow away through the guide groove 15 to prevent rainwater from accumulating around the sealing surface 12 for a long time and leaking into the cabin; wherein, the sealing surface 12 is a sealing surface formed by the deformation of the sealing strip 14 squeezed by the sealing baffle 13 in the locked state.

[0033] In practical applications, the design of the guide groove 15 should avoid the accumulation of liquids such as rain near the sealing surface 12 when the helicopter is flying or parked in any mission scenario. The amount of extrusion deformation of the sealing strip by the sealing baffle in the locked state should be appropriately selected so that the sealing surface can still be effective when affected by factors such as cover deformation and manufacturing tolerance. The design of the sealing component should be verified by a rain sealing test in the installed state.

[0034] Specifically, the flap assembly 1 is connected to the body by a hinge 10, and a locking mechanism 8 is used to fix the flap assembly 1. The locking force of the locking mechanism 8 is greater than 1.5 times the connection strength.

[0035] It should be noted that, considering the convenience of opening, the opening cover assembly 1 is preferably opened by using a hinge 10 to connect with the body structure 11, and a locking mechanism 8 is used to fix the opening cover assembly 1. The position of the locking mechanism 8 is determined according to the connection strength requirements and rigidity requirements. The locking force of the locking mechanism 8 is greater than 1.5 times the connection strength. The number and distance of the connection points of the locking mechanism 8 are adjusted to control the deformation of the opening cover assembly 1 against the force of the sealing strip 22.

[0036] The types of the supporting structure 9 include gas-elastic struts and mechanical struts.

[0037] Specifically, if the gas elastic force extension line of the gas elastic strut in the closed state can be achieved on the inside of the rotation center of the hinge 10 due to the shape and structure restrictions, the gas elastic strut is selected as the support structure 9. In the open state, the gas elastic strut is arranged so that the gas elastic force extension line is outside the rotation center of the hinge 10, and the gas elastic force of the support structure 9 is greater than 1.5 times the sum of the closing force in the direction of the gas elastic strut generated by the deadweight of the flap and the additional load in the use scenario; in the closed state, the gas elastic force extension line of the support structure 9 is inside the rotation center of the hinge, thereby forming a locking force for closing the flap.

[0038] Specifically, if it is not possible to place the gas elastic force extension line of the gas elastic strut on the inner side of the rotation center of the hinge 10 in the closed state due to shape and structural limitations, a mechanical strut is selected as the supporting structure.

[0039] Key points of this application

[0040] a After the skin 2 is opened, the opening is strengthened by thickening the skin 2, adding an upper longitudinal horizontal piece 3, a lower longitudinal horizontal piece 4, a front frame 5, a rear frame 6 and a reinforcing plate 7;

[0041] b The surface normal N at any point P2 on the sealing surface and the movement direction of the corresponding closing point P1 on the middle cover when closed The range of ∠α is 0°~10°, so as to avoid damage and poor sealing caused by friction deformation of the sealing components;

[0042] c. The amount of extrusion deformation of the sealing strip 14 by the sealing baffle 13 in the locked state should be appropriately selected so that the sealing surface 12 can still be ensured to be effective when it is affected by factors such as deformation of the cover assembly 1 and manufacturing tolerance;

[0043] d. The design of the sealing components should be verified by a rain sealing test in the installed state;

[0044] e Select the supporting structure 9 according to its appearance and structural characteristics. If a gas-elastic strut is selected as the supporting structure 9, the gas elastic extension line of the gas-elastic strut should be on the inner side of the rotation center of the hinge 10 when the cover assembly 1 is closed, and on the outer side of the rotation center of the hinge 10 when the cover assembly 1 is open, so as to ensure that the cover assembly 1 can be opened and locked reliably and conveniently.

[0045] The locking force of the locking mechanism 8 is greater than 1.5 times the connection strength, and the supporting structure 9 can withstand a compressive load greater than 1.5 times the sum of the closing force in the direction of the gas elastic strut generated by the mouth cover's own weight and the additional load in the usage scenario, so that the mouth cover assembly 1 remains locked or opened safely and reliably.

[0046] In summary, the present application provides a helicopter rain seal cover, which is practical and versatile; covers the cover rain seal, maintainability, reliability design, etc.; converts the design constraints of the sealing component and the supporting structure into geometric parameter design, and has high design accuracy. The present application is used for the design of helicopter rain seal cover scheme, which has comprehensive elements and strong applicability, and can be widely used in the design of helicopter cover scheme.

Claims

1. A helicopter rain sealing cover, characterized in that: The mouth cover comprises a mouth cover assembly (1), a cover skin (2), a reinforcement structure, a sealing assembly, a support assembly (9), and a locking mechanism (10), wherein: The reinforcement structure comprises an upper longitudinal horizontal member (3), a lower longitudinal horizontal member (4), a front frame (5), a rear frame (6) and a reinforcement plate (7); the sealing assembly comprises a sealing baffle (13), a sealing rubber strip (14) and a guide groove (15); the upper longitudinal horizontal member (3), the lower longitudinal horizontal member (4), the front frame (5) and the rear frame (6) are all long plate frame structures, and in order to prevent local instability due to compression, the width-to-thickness ratio of the inner edge strip is less than 12; the upper longitudinal horizontal member (3), the lower longitudinal horizontal member (4), the front frame (5) and the rear frame (6) are installed on the inner side of the skin (2) by rivet connection; the edge strip and the web at the intersection of the upper longitudinal horizontal member (3) and the front frame (5) and the rear frame (6) are disconnected, and the edge strip and the web at the intersection of the lower longitudinal horizontal member (4) and the front frame (5) and the rear frame (6) are disconnected, and the web is bent. The front frame (5) and the rear frame (6) are connected and installed with the webs of the front frame (5) and the rear frame (6) by rivets, and the reinforcing plate (7) is placed between the upper longitudinal horizontal member (3), the lower longitudinal horizontal member (4), the edge strips of the front frame (5) and the rear frame (6) and the skin (1), and installed by rivet connection; if it can be achieved that the gas elastic force extension line of the gas elastic strut in the closed state is inside the rotation center of the hinge (10), the gas elastic strut is selected as the support structure (9); in the open state, the gas elastic strut is arranged so that the gas elastic force extension line is outside the rotation center of the hinge (10), and the gas elastic force of the support structure (9) is greater than 1.5 times the sum of the closing force in the direction of the gas elastic strut generated by the deadweight of the cover and the additional load in the use scenario; in the closed state, the gas elastic force extension line of the support structure (9) is inside the rotation center of the hinge, thereby forming a locking force for closing the cover.

2. The helicopter rain sealing cover according to claim 1, characterized in that: The opening of the skin (2) is thickened, and the thickness of the skin (2) is determined according to the average shear flow to ensure that the shear stress of the skin (2) after thickening is less than the allowable stress of the material. Usually, the thickness of the opening of the skin (2) is 1.2 to 1.5 times the thickness of the skin in other areas without openings.

3. The helicopter rain sealing cover according to claim 1, characterized in that: The sealing surface (12) is a physical separation surface having a shower sealing effect between the movable cover and the fixed body structure (15) in the locked state; for a shower sealing structure including a sealing baffle (13) component that does not deform significantly under pressure, the sealing surface refers to the action surface between the sealing baffle (13) and the sealing strip (14) fixed on the body structure (11).

4. The helicopter rain sealing cover according to claim 1, characterized in that: The surface normal N at any point P2 on the sealing surface and the movement direction of the corresponding closing point P1 on the middle cover when closed The resulting ∠α ranges from 0° to 10°.

5. The helicopter rain sealing cover according to claim 1, characterized in that: The sealing surface (12) is a sealing surface formed by the sealing baffle (13) squeezing the sealing rubber strip (14) and deforming it in a locked state.

6. The helicopter rain sealing cover according to claim 1, characterized in that: The mouth cover assembly (1) is connected to the body by means of a hinge (10), and a locking mechanism (8) is used to fix the mouth cover assembly (1), wherein the locking force of the locking mechanism (8) is greater than 1.5 times the connection strength.

7. The helicopter rain sealing cover according to claim 1, characterized in that: The types of support structures (9) include gas-elastic struts and mechanical struts.

8. The helicopter rain sealing cover according to claim 7, characterized in that: If it is not possible to ensure that the gas elastic force extension line of the gas elastic strut is inside the rotation center of the hinge (10) in the closed state, a mechanical strut is selected as the supporting structure.

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