A push-in hot-melt plug for aircraft wheels

Abstract

The present invention relates to a push-in hot-melt plug for aircraft wheels, comprising a shell, a core body, and a sealing ring. The shell is a rotating body, and a through hole is arranged inside, and the through hole is a truncated cone hole with a taper of 1:10. The through hole is used to install the core body, and an annular groove is arranged on the outer circumferential surface of the shell body for installing the sealing ring. The core body is located in the truncated cone hole of the shell body, and the core body and the truncated cone hole of the shell body are interference fit, and the core body is made of a low melting point alloy material. The sealing ring is a circular ring with an elliptical cross-section, which is located in the annular groove of the shell body and is made of heat-resistant rubber. Compared with the existing threaded hot-melt plug, the stress concentration at the hot-melt plug hole of the wheel hub is reduced, thereby improving the life and reliability of the wheel hub; the use of a sealing ring for fixed connection makes the disassembly of the push-in hot-melt plug more convenient, and when replacing it, a screw or tool with a corresponding thread is used to screw it in and then pull it out.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft brake device components, and in particular relates to a push-in hot-melt plug for aircraft wheels. Background Art

[0002] The aviation brake device is one of the most important safety mechanisms of an aircraft during takeoff and landing. In the aviation brake device, the thermal fuse is one of its main components.

[0003] The hot melt plug is an important heat-sensitive pressure-release device for tubeless brake wheels. It can ensure that the inner core of the wheel melts in time to release tire pressure when the brake temperature is too high, avoiding dangerous accidents such as tire blowout caused by excessive tire pressure, thereby ensuring aircraft safety.

[0004] At present, the hot melt plugs used in China are threaded connections, which require the processing of matching threads on the wheel hub wall. Since the wheel hub is the main load-bearing part, the hub wall needs to withstand alternating loads for a long time during use, and the sharp point structure of the thread is prone to stress concentration. Under the alternating combination of multiple working conditions, fatigue cracks may occur due to stress corrosion and other reasons, thereby affecting the life of the wheel and even its safety. In the fatigue life tests of various types of wheel products, it was found that fatigue cracks caused by the influence of the hot melt plug thread sharp points have had a significant negative impact on the life assessment and research and development progress of the wheel products, such as Figure 1 , Figure 2 shown.

[0005] Chinese invention patent CN207156853U discloses a wheel with a hot melt plug, which includes a wheel hub, a tire and a hot melt plug, the wheel hub includes a wheel hub arm and a wheel hub web, the tire is mounted on the wheel hub arm; a threaded hole is provided at the connection between the wheel hub arm and the wheel hub web, the hot melt plug cooperates with the threaded hole, and the bottom of the threaded hole has a through hole connected to the inside of the tire; the hot melt plug includes a low-melting core body and a shell, the low-melting core body is located inside the shell, and the shell has a thread that cooperates with the threaded hole. The hot melt plug needs to be machined on the wall of the wheel hub, and the sharp point structure of the thread forms stress concentration and produces fatigue cracks.

[0006] In summary, threaded hot-melt plugs require matching threads to be processed on the wall of the wheel hub. The sharp point structure of the thread forms stress concentration, which is prone to fatigue cracks caused by stress corrosion and other reasons, thereby affecting the life of the wheel and causing varying degrees of impact on the use and development of aircraft wheels. Summary of the invention

[0007] In order to overcome the disadvantage that the existing threaded connection of the hot melt plug causes stress concentration in the wheel hub, the present invention discloses a push-in hot melt plug for an aircraft wheel.

[0008] The technical solution adopted by the present invention to solve its technical problem is:

[0009] A push-in hot-melt plug for aircraft wheels comprises a shell, a core body and a sealing ring, wherein the core body is located inside the shell body, the sealing ring is located outside the shell body, and the sealing ring, the shell body and the core body are connected in sequence from outside to inside.

[0010] The above-mentioned push-in hot-melt plug, the shell is a rotating body, a circular ring structure with a boss, the boss end is the outer side; the inside is a through hole, the center line of the through hole coincides with the center line of the rotating body, the through hole is a frustum hole, the hole diameter is slightly larger at the boss end, that is, slightly larger on the outer side; an annular groove is arranged on the outer circumferential surface, which is a copper alloy.

[0011] The sealing ring is located in the annular groove; the core body is located in the truncated cone hole and is made of a low melting point alloy material.

[0012] In the above-mentioned push-in hot-melt plug, the cross-section of the annular groove of the shell is rectangular, and the annular groove is far away from the outside of the shell and is located at 3 / 4 of the length of the shell.

[0013] The push-in hot-melt plug has a core body of a rotating body structure, a truncated cone shape, the taper of the truncated cone is equal to the taper of the truncated cone hole of the shell, and the height of the truncated cone is equal to the length of the truncated cone hole of the shell. The core body is located in the truncated cone hole of the shell, and the core body and the truncated cone hole of the shell are interference fit. The core body is a low melting point alloy material, and the melting temperature is 183±10℃~190±10℃.

[0014] The above-mentioned push-in hot-melt plug, the sealing ring is a circular ring with an elliptical cross-section, located in the groove of the shell, matching the groove of the shell, and is made of heat-resistant rubber material, with a stretching amount of 1.03-1.05%, a compression amount of 18-22%, and a static seal.

[0015] In the above-mentioned push-in hot-melt plug, the through hole of the shell consists of a threaded hole and a truncated cone hole. The threaded hole is located near the outside and the truncated cone hole is located near the inside. The diameter of the threaded hole is larger than the maximum diameter of the truncated cone hole. The taper of the truncated cone hole is 1:10 and is used to install the core body. The core body is a rotating body structure, truncated cone-shaped, the taper of the truncated cone is equal to the taper of the truncated cone hole of the shell, and the height of the truncated cone is equal to the length of the truncated cone hole of the shell; the core body is located in the truncated cone hole of the shell, and the core body and the truncated cone hole of the shell are interference fit.

[0016] A push-in hot-melt plug for an aircraft wheel may also be composed of a shell and a sealing ring, wherein the sealing ring is located outside the shell;

[0017] The shell is a rotating body, a cylindrical structure with a boss, the boss end is the outer side, a blind hole is arranged at the center of the outer side, the blind hole is perpendicular to the center of the outer side of the shell, is a threaded hole, and is made of a low melting point alloy material, an annular groove is arranged on the outer circumferential surface, and the annular groove is used to install the sealing ring;

[0018] The sealing ring is a circular ring with an elliptical cross section, is located in the groove of the shell, matches the groove of the shell, and is made of heat-resistant rubber.

[0019] The beneficial effects of the present invention are:

[0020] A push-in hot-melt plug for an aircraft wheel has a sealing ring disposed on the outer circumference of the shell, and the sealing ring forms a fixed connection between the shell and the wheel. The wheel hub that matches the push-in hot-melt plug is improved accordingly, that is, the threaded hole of the wheel hub is changed into a through hole, and the through hole arm is smooth, which is used to install the push-in hot-melt plug. Compared with the existing threaded hot-melt plug, the threaded structure of the hot-melt plug is cancelled, which can eliminate factors such as threaded holes that may cause original cracks in the wheel, reduce stress concentration at the hot-melt plug hole of the wheel hub, and thus improve the life and reliability of the wheel hub; the use of a sealing ring for fixed connection makes the disassembly of the push-in hot-melt plug more convenient, and when replacing it, it can be screwed in and then pulled out using a screw or tool with a corresponding thread.

[0021] The push-in hot melt plug structure of the present invention is pushed into the hot melt plug hole of the wheel hub after being matched with the corresponding sealing ring during installation. The hot melt plug of this structure cancels the thread structure, thereby eliminating factors such as threads that may cause original cracks, greatly improving the life and reliability of the wheel hub, and reducing stress concentration at the hot melt plug hole of the wheel hub. According to simulation calculations, the maximum stress at the push-in hot melt plug on the wheel hub is 131.8MPa, and the life is infinite. As shown in Figure 4.

[0022] The push-in hot-melt plug housing of the present invention is made of copper alloy, which has good mechanical properties and can withstand cold and hot pressure processing, and the push-in hot-melt plug has good corrosion resistance.

[0023] The core of the push-in hot-melt plug of the present invention has a melting point of 183±10° C. to 190±10° C. When the brake temperature is too high, the core will melt in time to release the tire pressure; if the wheel is disassembled without removing the tire, it is impossible to replace the hot-melt plug, thereby improving the operation safety.

[0024] A push-in hot melt plug with a shell as the core material, such as Figure 6 As shown, the hot melt plug is in more complete contact with the hot melt plug hole and is more sensitive to the temperature of the wheel; secondly, when the temperature of the wheel rises, the shell of the low-melting alloy material melts, and the hot melt plug hole leaks directly, which is faster and more sensitive than exhausting through the hot melt plug shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0026] Figure 1 It is a half-section view of a hexagonal threaded hot-melt plug along the center line;

[0027] Figure 2 It is a half-section view of a round-head threaded hot-melt plug along the center line;

[0028] Figure 3 is a cross-sectional view of the present invention along the center line;

[0029] FIG4(a) is a stress diagram near the hot melt plug hole of the wheel hub of the present invention;

[0030] FIG4( b ) is a diagram showing the thermal fatigue life near the hot melt plug hole of the wheel hub of the present invention;

[0031] Figure 5 It is a cross-sectional view of a threaded push-in hot-melt plug along the center line;

[0032] Figure 6 It is a cross-sectional view along the center line of a push-in hot-melt plug whose shell is made of a low-melting alloy material;

[0033] Figure 7 is a schematic diagram of a push-in hot-melt plug housing of Embodiment 1;

[0034] Figure 8 is a schematic diagram of a push-in hot-melt plug housing of Embodiment 2;

[0035] Fig. 9 It is a cross-sectional view along the centerline of the wheel and passing through the centerline of the push-in thermal plug.

[0036] In the figure: 1. wheel hub; 2. wheel rim; 3. hot melt plug; 4. shell; 5. core; 6. sealing ring. DETAILED DESCRIPTION

[0037] Example 1

[0038] A push-in hot-melt plug for an aircraft wheel comprises a shell 4, a core 5 and a sealing ring 6.

[0039] like Figure 3 As shown, the core 5 is located inside the shell 4, and the sealing ring 6 is located outside the shell 4. The sealing ring 6, the shell 4, and the core 5 are connected in sequence from the outside to the inside.

[0040] The housing 4 is a rotating body with a circular ring structure with a boss, such as Figure 7As shown, the boss end is the outer side. A through hole is provided inside the rotating body, and the center line of the through hole coincides with the center line of the rotating body. The through hole is a truncated cone hole, and the taper of the truncated cone hole is 1:10. The aperture is slightly larger at the boss end, that is, slightly larger on the outer side. The truncated cone hole is used to install the core 5. When the hub temperature rises to the melting temperature of the core 5, the core 5 melts, and the compressed gas in the tire is discharged from the through hole. An annular groove is provided on the outer circumferential surface of the shell 4. The cross section of the annular groove is rectangular. The annular groove is away from the outer side of the shell 4 and is located at 3 / 4 of the length of the shell 4. It is used to install the sealing ring 6. The shell 4 is a copper alloy.

[0041] The core 5 is a rotating body structure, truncated cone-shaped, the taper of the truncated cone is equal to the taper of the truncated cone hole of the shell 4, and the height of the truncated cone is equal to the length of the truncated cone hole of the shell 4. The core 5 is located in the truncated cone hole of the shell 4, and the core 5 and the truncated cone hole of the shell 4 are interference fit. The core 5 is a low melting point alloy material with a melting temperature of t 1 ,t 1 =190±10℃.

[0042] The sealing ring 6 is a circular ring with an elliptical cross-section, located in the annular groove of the housing 4 and matched with the annular groove of the housing 4. The sealing ring 6 is heat-resistant rubber with a stretching amount of 1.05% and a compression amount of 22%. The sealing form is a static seal.

[0043] The push-in hot-melt plug is installed in the hot-melt plug hole of the wheel hub. The hot-melt plug and the hot-melt plug hole form an interference fit through the sealing ring 6, so that the hot-melt plug and the wheel hub are fixedly connected.

[0044] Example 2

[0045] The through hole of the housing 4 may also be composed of a threaded hole and a truncated cone hole, wherein the threaded hole is located near the outer side and the truncated cone hole is located near the inner side. Figure 5 , Figure 8 As shown, the through hole of the housing 4 is divided into a threaded hole and a truncated cone hole. The threaded hole is used to connect the loading and unloading tools to facilitate the loading and unloading of the hot melt plug; the truncated cone hole has a taper of 1:10 and is used to install the core 5. The diameter of the threaded hole is larger than the maximum diameter of the truncated cone hole. The housing 4 is made of copper alloy.

[0046] The stretching amount of the sealing ring 6 is 1.03%, and the compression amount is 18%.

[0047] The core 5 is a rotating body structure, truncated cone-shaped, the taper of the truncated cone is equal to the taper of the truncated cone hole of the shell 4, and the height of the truncated cone is equal to the length of the truncated cone hole of the shell 4. The core 5 is located in the truncated cone hole of the shell 4, and the core 5 and the truncated cone hole of the shell 4 are interference fit. The core 5 is a low melting point alloy material with a melting temperature of t 2 ,t 2 =183±10℃.

[0048] Example 3

[0049] The push-in hot melt plug can also be composed of a shell 4 and a sealing ring 6. The shell 4 is made of a low melting point alloy material with a melting temperature of t 3 ,t 3 =185±10℃. Figure 6 As shown, a blind hole is provided at the center of the outer side of the housing 4. The blind hole is perpendicular to the center of the outer side of the housing 4 and is a threaded hole for connecting a loading and unloading tool to facilitate loading and unloading of the push-in hot melt plug.

[0050] The stretching amount of the sealing ring 6 is 1.04%, and the compression amount is 20%.

[0051] When the temperature of the wheel hub rises to the melting temperature of the shell 4, the shell 4 melts, and the compressed gas in the tire is discharged from the hot melt plug hole of the wheel hub.

[0052] Example 4

[0053] A wheel using a push-in hot-melt plug comprises a hub 1, a rim 2 and a hot-melt plug 3. Fig. 9 As shown, the wheel hub 1 is provided with a hot melt plug hole, which is a through hole and has a smooth inner circumference. The hot melt plug 3 is a push-in hot melt plug, which is located in the hot melt plug hole and matches the hot melt plug hole of the wheel hub 1; the shell 4 of the hot melt plug 3 and the hot melt plug hole of the wheel hub 1 are fixedly connected through a sealing ring 6, which seals the hot melt plug 3 and the hot melt plug hole on the wheel hub 1, and the boss end of the shell 4 is located outside the circumference of the wheel hub 1, and the wheel rim 2 is connected to the wheel hub 1. When the temperature of the wheel hub 1 reaches the melting temperature of the hot melt plug 3, the low-melting alloy material melts, and the gas inside the tire is released from the hot melt plug 3, avoiding the occurrence of tire blowout accidents caused by excessive tire pressure, thereby reducing aircraft safety risks.

Claims

1. A push-in hot-melt plug for aircraft wheels, It is characterized in that It comprises a shell (4), a core (5), and a sealing ring (6), wherein the core (5) is located inside the shell (4), the sealing ring (6) is located outside the shell (4), and the sealing ring (6), the shell (4), and the core (5) are connected in sequence from outside to inside; The shell (4) is a rotating body, a circular ring structure with a boss, the boss end is the outer side; the interior is a through hole, the center line of the through hole coincides with the center line of the rotating body, the through hole is a truncated cone hole, or a threaded hole and a truncated cone hole, the threaded hole is used to connect the loading and unloading tools, the taper of the truncated cone hole is 1:10, the hole diameter is slightly larger at the boss end, that is, slightly larger on the outer side; an annular groove is provided on the outer circumferential surface, which is a copper alloy; the sealing ring (6) is located in the annular groove; the core body (5) is located in the truncated cone hole, which is a low melting point alloy material; The cross section of the annular groove of the shell (4) is rectangular, and the annular groove is away from the outside of the shell (4) and is located at 3 / 4 of the length of the shell (4); The core body (5) is a rotating body structure, in the shape of a truncated cone, the taper of the truncated cone is equal to the taper of the truncated cone hole of the shell (4), and the height of the truncated cone is equal to the length of the truncated cone hole of the shell (4); the core body (5) is located in the truncated cone hole of the shell (4), and the core body (5) and the truncated cone hole of the shell (4) are interference fit; the core body (5) is made of a low melting point alloy material, and the melting temperature is 183±10°C or 190±10°C; The sealing ring (6) is a circular ring with an elliptical cross-section, located in the groove of the housing (4), matching the groove of the housing (4), and is made of heat-resistant rubber material, with a tensile strength of 1.03-1.05%, a compression strength of 18-22%, and a static seal; The wheel hub is provided with a through hole with a smooth hole arm for installing a push-in hot melt plug.

2. The push-in hot-melt plug for aircraft wheels according to claim 1, It is characterized in that The through hole of the shell (4) consists of a threaded hole and a truncated cone hole, wherein the threaded hole is located near the outside and the truncated cone hole is located near the inside; the diameter of the threaded hole is greater than the maximum diameter of the truncated cone hole; the taper of the truncated cone hole is 1:10 and is used to install the core body (5); the core body (5) is a rotating body structure and is truncated cone-shaped; the taper of the truncated cone is equal to the taper of the truncated cone hole of the shell (4); the height of the truncated cone is equal to the length of the truncated cone hole of the shell (4); the core body (5) is located in the truncated cone hole of the shell (4), and the core body (5) and the truncated cone hole of the shell (4) are interference fit.

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