A thermal protection structure and concealed quick installation method

Abstract

The present invention belongs to the technical field of aircraft structure installation, and relates to a thermal protection structure and a concealed quick installation method. The thermal protection structure includes a load-bearing skin, a load-bearing lock assembly, a strain isolation pad, an adhesive film, and an anti-heat insulation layer; the concealed quick installation method includes drilling installation holes, installing a load-bearing lock rod assembly, installing an anti-heat insulation layer, forming a thermal protection structure, resetting the load-bearing lock trigger lock tongue, positioning the thermal protection structure, and locking the air spring load-bearing lock rod installation steps. The load-bearing lock of the present invention is concealed under the anti-heat insulation layer of the thermal protection structure, and the anti-heat insulation layer is non-destructive, thereby achieving the purpose of not damaging the anti-heat insulation layer; the load-bearing lock is used as a connecting piece, thereby improving the installation efficiency of a single connecting piece; by pressing the surface of the thermal protection structure, multiple load-bearing locks are synchronously locked, thereby further improving the installation efficiency of the entire thermal protection structure. At the same time, the air spring load-bearing lock rod is retractable, which solves the interference problem of synchronous installation on a curved structure.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft structure installation, and relates to a thermal protection structure and a concealed quick installation method. Background Art

[0002] A large number of thermal protection structures are used on the surface of high-speed aircraft. Due to the limitations of current technology, after a flight mission, the thermal protection structure will usually have peeling, cracking, debonding and other failures that endanger the integrity of the thermal protection structure. In order to ensure flight safety, the current maintenance plan is to replace all thermal protection structures after each flight mission. The traditional thermal protection structure and the skin are separated by a design. The thermal protection structure is bonded to the skin with high-temperature glue. Because the skin cannot be removed, when replacing the thermal protection structure, the original thermal protection structure must be removed from the skin first, and then the new thermal protection structure is bonded. On the one hand, the original glue layer is difficult to remove, and on the other hand, the new glue layer needs a long time to cure, resulting in a long maintenance cycle for the thermal protection structure. Based on the demand for rapid maintenance, a large-size thermal insulation and load-bearing integrated thermal protection structure is designed for the new generation of high-speed aircraft. Its thermal insulation layer and the load-bearing skin are integrally formed and installed on the fuselage frame together by screwing. During maintenance, the entire thermal insulation and load-bearing integrated thermal protection structure is directly replaced without removing glue and waiting for curing, which shortens the maintenance time. However, in order to provide an installation channel for bolt fasteners, bolt mounting holes need to be set on the surface of the thermal protection structure, such as Fig.10 As shown, it not only affects the heat insulation effect of the heat protection structure, but also reduces the reliability of the heat protection structure. In addition, the installation efficiency of bolt fasteners is low, especially for large-sized heat insulation load-bearing integrated heat protection structural components. The number of bolt fasteners is large and the installation workload is huge. Although the maintenance time has been shortened compared to the traditional bonding method, it still cannot meet the rapid maintenance requirements in the context of short-term takeoff again. Therefore, for the large-sized heat insulation load-bearing integrated structure of the new generation of high-speed aircraft, in order to meet the reliability of the heat protection structure and the rapid maintenance requirements of the heat insulation load-bearing integrated structure, it is necessary to develop an installation method that can achieve no damage to the heat protection structure and has higher installation efficiency. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the current screw-connection installation method of the thermal protection structure, which damages the heat insulation layer and has low installation efficiency. The present invention provides a large-size heat insulation load-bearing integrated thermal protection structure and a concealed quick installation method. The present invention can realize the rapid and efficient installation of the thermal protection structure without damaging the heat insulation layer of the thermal protection structure, and at the same time has the characteristic of being load-bearing.

[0004] The technical solution of the present invention is: a thermal protection structure 201, including a load-bearing skin 101, a load-bearing lock assembly, a strain isolation pad 104, an adhesive film 105, and an anti-heat insulation layer 106, wherein the anti-heat insulation layer 106 is integrally formed with the load-bearing skin 101, the load-bearing skin 101 is sequentially bonded to the adhesive film 105, the strain isolation pad 104, the adhesive film 105, and the anti-heat insulation layer 106, a plurality of mounting holes 102 are arranged on the load-bearing skin 101, the load-bearing lock assembly includes a load-bearing lock rod assembly and a load-bearing lock nut 109, the load-bearing lock rod assembly is fixed to the load-bearing skin 101 through the mounting hole 102, and each mounting hole 102 is installed with a load-bearing lock rod assembly; the load-bearing lock nut 109 is fixed to the corresponding position of the body frame 202.

[0005] The load-bearing lock assembly includes an air spring load-bearing lock rod 103, a load-bearing lock trigger lock tongue 107, a lock rod seat 108, and a load-bearing lock nut seat 109; the air spring load-bearing lock rod 103 is placed in the lock rod seat 108, the load-bearing lock trigger lock tongue 107 is installed inside the air spring load-bearing lock rod 103, and the load-bearing lock nut seat 109 in the load-bearing lock assembly is fixed on the body frame 202.

[0006] The air spring load-bearing locking rod 103 is a hollow cylindrical structure with an annular outer groove.

[0007] The load-bearing lock triggering lock tongue 107 is a cylindrical pin structure.

[0008] The locking rod seat 108 is a cap-shaped structure, and an annular inner groove is arranged inside the locking rod seat 108, and an open clamping ring a151 is installed in the groove.

[0009] A ejector pin 110 is arranged in the middle of the load-bearing lock nut 109, and the ejector pin 110 is a conical structure. An annular inner groove is also arranged inside the load-bearing lock nut 109, and an open clamping ring b152 is installed in the groove.

[0010] The strain isolation pad 104 is woven from glass fibers and is flexible.

[0011] The adhesive film 105 is made of high temperature resistant GS100 flexible structural adhesive.

[0012] The anti-insulation layer 106 is made of aerogel with low density and low thermal conductivity.

[0013] The heat protection structure 201 is fixed to the body frame 202 by concealed installation. Before installation, positioning marks 203 are set on the heat protection structure 201 and the body frame 202 at corresponding positions. The positioning marks 203 are drawn on the surfaces of the heat protection structure 201 and the body frame 202 by ink painting.

[0014] The concealed quick installation method comprises:

[0015] Step 1, drilling installation holes: fix the load-bearing skin 101 on the special fixture 301, and drill installation holes 102 on the load-bearing skin 101;

[0016] Step 2, installing the load-bearing locking rod assembly: fixing the load-bearing locking rod assembly in the mounting hole 102 of the load-bearing skin 101 with rivets;

[0017] Step 3, installing the anti-heat insulation layer: placing the adhesive film 105, the strain isolation pad 104, the adhesive film 105 and the anti-heat insulation layer 106 in sequence on the load-bearing skin 101 equipped with the load-bearing locking rod assembly to form a preformed thermal protection structure;

[0018] Step 4, forming a heat protection structure: placing the preformed heat protection structure formed in step 3 in a forming device, heating it to 300-350° C., pressurizing it to 0.1-0.15 MPa, and curing it for 2-3 hours to solidify the adhesive film, thereby completing the forming of the heat protection structure 201;

[0019] Step 5, resetting the load-bearing lock triggering lock tongue: pressing all the air spring load-bearing lock rods 103 into the lock rod seat 108 in sequence to complete the resetting of the load-bearing lock triggering lock tongue 107;

[0020] Step 6, install the load-bearing lock nut: according to the load-bearing lock assembly installation hole pre-drilled on the body frame 202, install the load-bearing lock nut 109 on the body frame 202;

[0021] Step 7, positioning the heat protection structure: placing the heat protection structure 201 at the corresponding position of the body frame 202 according to the installation positioning mark;

[0022] Step 8, lock the air spring load-bearing lock rod: press downward the surface of the heat protection structure 201 so that the ejector pin 110 of the load-bearing lock nut 109 pushes open the load-bearing lock trigger tongue 107, and the load-bearing lock trigger tongue 107 further opens the opening clamping ring a151. Under the action of air pressure, the air spring load-bearing lock rod 103 pops up downward to open the opening clamping ring b152 of the load-bearing lock nut 109. When the opening clamping ring b152 slides into the annular outer groove of the air spring load-bearing lock rod 103, it is locked with the load-bearing lock nut 109 to complete the installation of the heat protection structure 201.

[0023] The beneficial effect of the present invention is that the load-bearing lock of the present invention is concealed under the heat-insulating layer of the heat protection structure, and the heat-insulating layer is intact, so the purpose of not damaging the heat-insulating layer is achieved; compared with the traditional screw connection method, the use of the load-bearing lock as a connecting piece improves the installation efficiency of a single connecting piece. A load-bearing lock trigger lock tongue is provided, and multiple load-bearing locks are synchronously locked by pressing the surface of the heat protection structure, further improving the installation efficiency of the entire heat protection structure. At the same time, the air spring load-bearing lock rod is retractable, which solves the interference problem of synchronous installation on a curved structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a flow chart of the installation method of the present invention.

[0025] Figure 2 It is a schematic diagram of the fixation of the load-bearing skin on a special fixture.

[0026] Figure 3 It is a schematic diagram of the installation position and internal structure of the load-bearing lock rod assembly in the load-bearing skin.

[0027] Figure 4 It is a schematic diagram of the preformed thermal protection structure of the present invention.

[0028] Figure 5 It is a schematic diagram of the thermal protection structure of the present invention.

[0029] Figure 6 It is a schematic diagram of the installation position and internal structure of the load-bearing lock rod assembly of the present invention in the thermal protection structure.

[0030] Figure 7 It is a schematic diagram of the installation of the thermal protection structure of the present invention on the body frame.

[0031] Figure 8 It is a schematic diagram of locking the load-bearing lock of the thermal protection structure of the present invention.

[0032] Fig. 9 It is a structural schematic diagram of the load-bearing lock assembly of the present invention.

[0033] Fig.10 The present invention is a schematic diagram of an existing thermal protection structure installation method after installation.

[0034] Among them: 101-load-bearing skin, 102-mounting hole, 103-air spring load-bearing lock rod, 104-strain isolation pad, 105-adhesive film, 106-anti-insulation layer, 107-load-bearing lock trigger lock tongue, 108-lock rod seat, 109-load-bearing lock nut seat, 110-thimble, 151-opening clamp a, 152-opening clamp b, 201-thermal protection structure, 202-body frame, 203-positioning mark, 301-special clamp. DETAILED DESCRIPTION

[0035] The present invention is further described below in conjunction with the accompanying drawings:

[0036] like Figure 2-Figure 9 As shown, a heat protection structure 201 includes a load-bearing skin 101, a load-bearing lock assembly, a strain isolation pad 104, an adhesive film 105, and an anti-heat insulation layer 106, wherein the anti-heat insulation layer 106 is integrally formed with the load-bearing skin 101, the load-bearing skin 101 and the adhesive film 105, the strain isolation pad 104, the adhesive film 105, and the anti-heat insulation layer 106 are sequentially bonded, a plurality of mounting holes 102 are arranged on the load-bearing skin 101, the load-bearing lock assembly includes a load-bearing lock rod assembly and a load-bearing lock nut 109, the load-bearing lock rod assembly is fixed to the load-bearing skin 101 through the mounting holes 102, and each mounting hole 102 is installed with a load-bearing lock rod assembly; the load-bearing lock nut 109 is fixed to the corresponding position of the body frame 202.

[0037] The load-bearing lock assembly includes an air spring load-bearing lock rod 103, a load-bearing lock trigger lock tongue 107, a lock rod seat 108, and a load-bearing lock nut seat 109; the air spring load-bearing lock rod 103 is placed in the lock rod seat 108, the load-bearing lock trigger lock tongue 107 is installed inside the air spring load-bearing lock rod 103, and the load-bearing lock nut seat 109 in the load-bearing lock assembly is fixed on the body frame 202; the air spring load-bearing lock rod 103 is a hollow cylinder with an annular outer groove shaped structure; the load-bearing lock trigger lock tongue 107 is a cylindrical pin structure; the lock rod seat 108 is a cap-shaped structure, and an annular inner groove is arranged inside the lock rod seat 108, and an open clamp ring a151 is installed in the groove; the open clamp ring a151 is a standard part, which is mainly used to lock the air spring load-bearing lock rod 103 after being pressed into the lock rod seat 108; the air spring load-bearing lock rod 103, the load-bearing lock trigger lock tongue 107, the lock rod seat 108, and the load-bearing lock nut seat 109 are all made of alloy steel.

[0038] The load-bearing lock nut 109 is provided with a push pin 110 in the middle. The push pin 110 is a conical structure and is mainly used to push open the load-bearing lock trigger lock tongue 107 to make the air spring load-bearing lock rod 103 pop out; the load-bearing lock nut 109 is also provided with an annular inner groove inside, and an open clamping ring b152 is installed in the groove. The open clamping ring b152 is a standard part and is mainly used to lock the air spring load-bearing lock rod 103 that pops out after being triggered.

[0039] The strain isolation pad 104 is woven from glass fibers and is flexible. Its main function is to coordinate the deformation of the anti-insulation layer 106 and the load-bearing skin 101 .

[0040] The adhesive film 105 is made of high temperature resistant GS100 flexible structural adhesive.

[0041] The anti-insulation layer 106 is made of aerogel with low density and low thermal conductivity, and mainly plays a role of heat insulation.

[0042] The mounting holes 102 are drilled on the load-bearing skin 101. The fuselage frame 202 is the mounted structure of the thermal protection structure of the present invention, which is determined by the actual structure. The load-bearing skin 101 is made of titanium alloy sheet metal and is mainly used to withstand aerodynamic forces. The size and thickness are determined according to design requirements.

[0043] Multiple heat protection structures 201 are fixed to the body frame 202 by concealed installation. Before installation, each heat protection structure 201 and the body frame 202 at the corresponding position are provided with a positioning mark 203, and the positioning mark 203 is drawn on the surface of the heat protection structure 201 and the body frame 202 by the paint ink method.

[0044] like Figure 1 As shown, the concealed quick installation method comprises:

[0045] Step 1, drilling installation holes: fix the load-bearing skin 101 on the special fixture 301, and drill installation holes 102 on the load-bearing skin 101;

[0046] Step 2, installing the load-bearing locking rod assembly: fixing the load-bearing locking rod assembly in the mounting hole 102 of the load-bearing skin 101 with rivets;

[0047] Step 3, installing the anti-heat insulation layer: placing the adhesive film 105, the strain isolation pad 104, the adhesive film 105 and the anti-heat insulation layer 106 in sequence on the load-bearing skin 101 equipped with the load-bearing locking rod assembly to form a preformed thermal protection structure;

[0048] Step 4, forming a heat protection structure: placing the preformed heat protection structure formed in step 3 in a forming device, heating it to 300-350° C., pressurizing it to 0.1-0.15 MPa, and curing it for 2-3 hours to solidify the adhesive film, thereby completing the forming of the heat protection structure 201;

[0049] Step 5, resetting the load-bearing lock triggering lock tongue: pressing all the air spring load-bearing lock rods 103 into the lock rod seat 108 in sequence to complete the resetting of the load-bearing lock triggering lock tongue 107;

[0050] Step 6, install the load-bearing lock nut: according to the load-bearing lock assembly installation hole pre-drilled on the body frame 202, install the load-bearing lock nut 109 on the body frame 202;

[0051] Step 7, positioning the heat protection structure: placing the heat protection structure 201 at the corresponding position of the body frame 202 according to the installation positioning mark;

[0052] Step 8, lock the air spring load-bearing lock rod: press downward the surface of the heat protection structure 201 so that the ejector pin 110 of the load-bearing lock nut 109 pushes open the load-bearing lock trigger tongue 107, and the load-bearing lock trigger tongue 107 further opens the opening clamping ring a151. Under the action of air pressure, the air spring load-bearing lock rod 103 pops up downward to open the opening clamping ring b152 of the load-bearing lock nut 109. When the opening clamping ring b152 slides into the annular outer groove of the air spring load-bearing lock rod 103, it is locked with the load-bearing lock nut 109 to complete the installation of the heat protection structure 201.

Claims

1. A heat protection structure (201), characterized in that: The invention comprises a load-bearing skin (101), a load-bearing lock assembly, a strain isolation pad (104), an adhesive film (105), and an anti-heat insulation layer (106); the anti-heat insulation layer (106) and the load-bearing skin (101) are integrally formed, the load-bearing skin (101) and the adhesive film (105), the strain isolation pad (104), the adhesive film (105), and the anti-heat insulation layer (106) are sequentially bonded, a plurality of mounting holes (102) are arranged on the load-bearing skin (101), the load-bearing lock assembly comprises a load-bearing lock rod assembly and a load-bearing lock nut (109), the load-bearing lock rod assembly is fixed on the load-bearing skin (101) through the mounting holes (102), and each mounting hole (102) is installed with a load-bearing lock rod assembly; the load-bearing lock nut (109) is fixed on a corresponding position of the body frame (202); The load-bearing lock assembly comprises an air spring load-bearing lock rod (103), a load-bearing lock trigger lock tongue (107), a lock rod seat (108), and a load-bearing lock nut seat (109); the air spring load-bearing lock rod (103) is placed in the lock rod seat (108), the load-bearing lock trigger lock tongue (107) is installed inside the air spring load-bearing lock rod (103), and the load-bearing lock nut seat (109) in the load-bearing lock assembly is fixed on the body frame (202).

2. The heat protection structure (201) according to claim 1, characterized in that: The air spring type load-bearing locking rod (103) is a hollow cylindrical structure with an annular outer groove.

3. The heat protection structure (201) according to claim 1, characterized in that: The load-bearing lock triggering lock tongue (107) is a cylindrical pin structure.

4. The heat protection structure (201) according to claim 1, characterized in that: The locking rod seat (108) is a cap-shaped structure. An annular inner groove is arranged inside the locking rod seat (108), and an opening collar a (151) is installed in the groove.

5. The heat protection structure (201) according to claim 1, characterized in that: A ejector pin (110) is arranged in the middle of the load-bearing lock nut (109), and the ejector pin (110) is a conical structure. An annular inner groove is also arranged inside the load-bearing lock nut (109), and an open clamping ring b (152) is installed in the groove.

6. The heat protection structure (201) according to claim 1, characterized in that: The strain isolation pad (104) is woven from glass fibers and is flexible.

7. The heat protection structure (201) according to claim 1, characterized in that: The adhesive film (105) is made of high temperature resistant GS100 flexible structural adhesive; the anti-heat insulation layer (106) is made of low-density, low-thermal conductivity aerogel.

8. The heat protection structure (201) according to claim 1, characterized in that: The heat protection structure (201) is fixed to the machine frame (202) by concealed installation. Before installation, positioning marks (203) are arranged on the heat protection structure (201) and the machine frame (202) at corresponding positions. The positioning marks (203) are drawn on the surfaces of the heat protection structure (201) and the machine frame (202) by a paint-ink method.

9. The heat protection structure (201) according to claim 1, characterized in that: The load-bearing lock assembly is concealed under the anti-heat-insulation layer (106) of the thermal protection structure, and the anti-heat-insulation layer (106) is intact.

10. The concealed quick installation method of the heat protection structure (201) according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1, drilling installation holes: fixing the load-bearing skin (101) on a special fixture (301), and drilling installation holes (102) on the load-bearing skin (101); Step 2, installing the load-bearing locking rod assembly: fixing the load-bearing locking rod assembly in the mounting hole (102) of the load-bearing skin (101) with rivets; Step 3, installing the anti-heat insulation layer: placing the adhesive film (105), the strain isolation pad (104), the adhesive film (105) and the anti-heat insulation layer (106) in sequence on the load-bearing skin (101) equipped with the load-bearing locking rod assembly to form a preformed thermal protection structure; Step 4, forming a heat protection structure: placing the preformed heat protection structure formed in step 3 in a forming device, heating it to 300-350° C., pressurizing it to 0.1-0.15 MPa, and curing it for 2-3 hours to solidify the adhesive film, thereby completing the forming of the heat protection structure (201); Step 5, resetting the load-bearing lock triggering lock tongue: pressing all the air spring load-bearing lock rods (103) into the lock rod seats (108) in sequence to complete the resetting of the load-bearing lock triggering lock tongue (107); Step 6, installing the load-bearing lock nut: according to the load-bearing lock assembly installation hole pre-drilled on the body frame (202), the load-bearing lock nut (109) is installed on the body frame (202); Step 7, positioning the heat protection structure: placing the heat protection structure (201) at a corresponding position of the body frame (202) according to the installation positioning mark; Step 8, lock the air spring load-bearing lock rod: press downward the surface of the heat protection structure (201) so that the ejector pin (110) of the load-bearing lock nut (109) pushes open the load-bearing lock trigger tongue (107), and the load-bearing lock trigger tongue (107) further opens the opening clamp ring a (151), and under the action of air pressure, the air spring load-bearing lock rod (103) pops up downward to open the opening clamp ring b (152) of the load-bearing lock nut (109), and when the opening clamp ring b (152) slides into the annular outer groove of the air spring load-bearing lock rod (103), it is locked with the load-bearing lock nut (109), and the installation of the heat protection structure (201) is completed.

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