JP2809052B2 - Nozzle holder heat insulating material attachment structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a nozzle holder used for mounting a nozzle of a rocket to an airframe, and more particularly to a heat insulating material for adhering a heat insulating material to the nozzle holder. It relates to a wearing structure.

[0002]

2. Description of the Related Art In order to protect the holder itself from high-temperature combustion gas, a heat insulating material made of CFRP (carbon fiber reinforced plastic) is provided on the inside of a combustion chamber of a steel nozzle holder for mounting a nozzle on a rocket body. This heat insulating material is conventionally provided with a rubber layer having a thickness of several mm in order to reduce the load stress based on the deformation of the nozzle holder when the combustion pressure at the time of ignition is applied. (See Japanese Utility Model Application Laid-Open No. 1-21).
244).

[0003]

However, in the above-mentioned conventional nozzle holder, the nozzle holder receives the combustion pressure despite the rubber layer being interposed between the nozzle holder and the heat insulating material. In addition, the heat-insulating material causes a deformation almost following the deformation of the nozzle holder.
It has been found that a stress exceeding the tensile strength of the RP is generated, and the heat insulating material may be broken. Of course, by increasing the thickness of the nozzle holder and the heat insulation itself to reduce the amount of these deformations, it is possible to prevent the heat insulation from being destroyed, but this will increase the weight of the rocket body Therefore, solving such a problem has been a structural problem of the nozzle holder of the rocket.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the conventional rocket nozzle holder, and can suppress deformation of the heat insulating material without increasing the weight of the fuselage. It is an object of the present invention to provide a heat insulating material sticking structure for a nozzle holder that can prevent breakage.

[0005]

In order to achieve the above object, the present inventor has used the finite element method or the like to determine the deformation state and stress load state of the nozzle holder and the heat insulating material during pressurization. As a result of detailed examination, it was found that there was a problem in the deformability of the rubber layer interposed between the nozzle holder and the heat insulating material.

That is, although the rubber layer is an elastic material, the rubber itself hardly shrinks in volume. Therefore, if the rubber layer intervenes on the entire surface between the nozzle holder and the heat insulating material, the rubber escapes during deformation. Because it is small, it can hardly be deformed, and the heat insulating material deforms to the shape along the deformation of the nozzle holder, resulting in destruction, especially increasing the volume compressibility of the rubber layers at both ends of the heat insulating material It has been found that by preventing the heat insulating material from following the deformation of the nozzle holder, the heat insulating material can be prevented from being broken.

The heat insulating material attaching structure of the nozzle holder according to the present invention is based on the above findings, and the heat insulating material is
It is characterized in that it is attached to the inside of the combustion chamber of the nozzle holder via an elastic material layer with high volume compressibility on the both edge sides and an elastic material layer with low volume compressibility on the center side. Thus, such a configuration of the nozzle holder is used as means for solving the above-described conventional problem. Further, as a specific embodiment of the heat insulating material attaching structure of the nozzle holder according to the present invention, the heat insulating material is provided with a solid rubber layer on the center side and a sponge-like rubber layer on both end edges. A configuration in which the heat insulating material is attached to the nozzle holder, or a rubber adhesive layer on the center side of the heat insulating material and a rubber adhesive layer mixed with microballoons such as silica microballoons on both edge sides. It is possible to adopt a configuration in which the heat insulating material is attached to the nozzle holder.

[0008]

In the structure for attaching the heat insulating material of the nozzle holder according to the present invention, the heat insulating material is provided at the both end edges of the nozzle holder through the elastic material layer having high volume compressibility such as sponge-like rubber. Has a structure in which it is attached to a nozzle holder via an elastic material layer having low volume compressibility such as solid rubber. Therefore, when the nozzle holder is deformed so as to be bent outward due to the combustion pressure, the distance from the nozzle holder is reduced by compression of the elastic material layer having high volume compressibility at both end sides of the heat insulating material, while the center of the heat insulating material is reduced. In the part, the distance from the nozzle holder is maintained at the thickness of the elastic material layer by the elastic material layer having low volume compressibility, so that the heat insulating material has a smaller deformation amount than the nozzle holder, and the generated stress is reduced. It will not be destroyed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings.

FIGS. 1 to 3 show one embodiment of a structure for attaching a heat insulating material to a nozzle holder according to the present invention. FIG. 1 shows a nozzle holder provided with a heat insulating material adhered by the structure. FIG. 3 is a cross-sectional view showing a rear part of the body of the rocket equipped with the nozzle according to the embodiment.

The rocket 1 shown in FIG.
/ C composite nozzle 2
In this embodiment, is mounted at the rear end of the combustion chamber 5 of the body via the flexible joint 3 and the nozzle holder 4.

The flexible joint 3 has a laminated structure of rubber and steel, flexibly supports the nozzle 2 with respect to the nozzle holder 4, deflects the nozzle 2 by an actuator (not shown), and thrusts the rocket 1. The direction is controlled. The flexible joint 3 is protected from high-temperature combustion gas by a heat protection boot 6 made of silicon rubber.

The nozzle holder 4 is made of nickel chromium molybdenum steel, and a heat insulating material 7 made of CFRP (carbon fiber reinforced plastic) is adhered to the inner surface of the combustion chamber by a structure described later. .

FIG. 2 is an enlarged sectional view of the nozzle holder 4 and the heat insulating material 7 shown in FIG. 1. As shown in FIG. , A rubber-based adhesive layer 9 containing silica microballoons mixed on both side edges thereof.
9 is attached to the nozzle holder 4.

The silica microballoon is obtained by coagulating fused silica into a hollow sphere having a diameter of 100 to several hundreds μm, and the rubber-based adhesive layer 9 mixed with the silica microballoon is subjected to a compression force. When the hollow portion of the silica microballoon is crushed, the volume is reduced, so that a rubber layer having high volume compressibility is formed.

As described above, the heat insulating material 7 is attached via the rubber adhesive layer 8 having a low volume compressibility and the rubber adhesive layers 9 having a high volume compressibility by mixing silica microballoons. When receiving the internal combustion pressure due to fuel ignition, the nozzle holder 4 deforms so that the central portion 4a of the nozzle holder 4 curves outward as shown in FIG.

At this time, the adhesive layer which has the heat insulating material 7 adhered to the nozzle holder 4 is a rubber-based adhesive layer 8 having almost no volume compressibility at the center thereof, so that it can be subjected to pressure. With almost no compression, the distance between the nozzle holder 4 and the heat insulating material 7 is maintained substantially at the original thickness of the adhesive layer 8.

On the other hand, since the rubber-based adhesive layers 9 and 9 adhering to both ends of the heat insulating material 7 are mixed with silica microballoons, the volume compressibility is high as described above, and when pressure is applied, Since it is easily compressed, it is compressed by the internal combustion pressure, and the distance between the nozzle holder 4 and the heat insulating material 7 is reduced. Therefore, the heat insulating material 7 hardly deforms despite the deformation of the nozzle holder 4 and is bent. Since the stress is greatly reduced, it is possible to prevent the heat insulating material 7 from being broken.

In the above embodiment, a rubber-based adhesive mixed with silica microballoons as an elastic material layer having high volume compressibility at both ends of the heat insulating material 7 is used. The example in which a rubber-based adhesive is used as the low elastic material layer has been described. In addition, the sponge-like rubber layer is provided on both ends of the heat insulating material 7 and the heat insulating material is provided on the center side through a normal solid rubber layer. 7 and the nozzle holder 4 may be adhered. Also, instead of silica microballoons, alumina microballoons, magnesia microballoons and the like can be used.

[0020]

As described above, the heat insulating material sticking structure of the nozzle holder according to the present invention has the above-mentioned structure, that is, an elastic material having a high volume compressibility such as a sponge-like rubber at both ends of the heat insulating material. Through the layers, on the center side, the heat insulating material is attached to the nozzle holder via a low volume compressible elastic material layer such as solid rubber, for example. Since the heat insulating material does not follow, a very excellent effect that the heat insulating material can be prevented from being broken without increasing the weight of the rocket body is exhibited.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a rear part of a rocket showing a state in which a nozzle is attached by a nozzle holder to which an embodiment of a heat insulating material sticking structure of a nozzle holder according to the present invention is applied.

FIG. 2 is an enlarged sectional view showing in detail a structure of a nozzle holder and a heat insulating material portion of the rocket shown in FIG.

FIG. 3 is a schematic diagram illustrating a deformation state when the nozzle holder and the heat insulating material illustrated in FIG. 2 receive a combustion internal pressure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rocket 2 Nozzle 4 Nozzle holder 7 Insulation material 8 Rubber adhesive 9 Rubber adhesive mixed with silica micro balloon

Claims (4)

(57) [Claims] 1. A heat insulating material adhering structure for adhering heat insulating material to an inner surface of a combustion chamber of a nozzle holder that is interposed between a body of a rocket and a nozzle and that attaches the nozzle to the body,
The heat insulating material is attached via an elastic material layer having a high volume compressibility on both end edge sides, and an elastic material layer having a low volume compressibility on a center side thereof. Insulation material attachment structure. 2. The heat insulating material is attached via a solid rubber layer on the center side and via a sponge-like rubber layer on both end edges.
A heat insulating material sticking structure of the nozzle holder according to the above. 3. The heat-insulating material is attached via a rubber-based adhesive layer on the center side and via a rubber-based adhesive layer mixed with microballoons on both end edges. The heat insulating material sticking structure of the nozzle holder according to claim 1. 4. The structure according to claim 3, wherein said micro-balloon is a silica micro-balloon.