JP2008037063A - Thermal insulation structure - Google Patents

Abstract

[PROBLEMS] For example, when used in an engine room of an automobile, the heat insulation cost is reduced and the heat insulation workability is improved, and various hydraulic hoses and various conductive wires that are wired in the engine room are used. Provided is a heat insulating structure capable of reliably protecting a tubular or linear part from a high temperature.
A heat insulating structure having a multi-layered structure and having a metal thin film layer 1 as a layer on the most surface side, wherein at least one heat conductive layer 2 is disposed on the back side of the metal thin film layer 1 and is most The back layer is the heat insulating layer 3, the thermal diffusion coefficient of the heat conductive layer 2 is larger than the heat diffusion coefficient of the heat insulating layer 3, and the ratio of the thickness of the heat insulating layer 3 to the thickness of the heat conductive layer 2 is 0. It was set to 05-5.
[Selection] Figure 1

Description

  The present invention is, for example, a heat insulating structure suitable for protecting tubular or linear parts such as various hydraulic hoses and various conductive wires that are piped and wired adjacent to a high temperature portion in an automobile engine room from high temperatures. It is about the body.

  As described above, for example, various hydraulic hoses and various conductive wires that are wired in an engine room of an automobile are heated by heat generated in the engine and its peripheral parts. The amount of heat generated increases as the engine becomes more powerful, and on the other hand, it is difficult to expand the space in the engine room due to restrictions on design and vehicle performance, avoiding the vicinity of high temperature parts Since piping wiring is difficult, the amount of heat received by various hydraulic hoses and various conductive wires tends to increase.

Conventionally, in order to prevent various hydraulic hoses and various electric wires from being exposed to high temperatures, a heat insulating material formed by laminating a heat reflecting layer as a surface layer and a heat insulating layer as a back surface layer, various hydraulic hoses And means for coating various conductive wires.
Japanese Patent No. 3073262

  However, the heat insulating material formed by laminating the heat reflecting layer and the heat insulating layer described above cannot be said to have high heat insulating performance with respect to the layout conditions required for the engine room of automobiles in recent years. Or a shielding plate must be installed separately from this heat insulating material. As a result, there is a problem that the heat insulation cost is increased and the heat insulation workability is deteriorated. Has become a conventional problem.

  The present invention has been made paying attention to the above-described conventional problems. For example, when used in an engine room of an automobile, the engine room is realized after reducing heat insulation cost and improving heat insulation workability. It is an object of the present invention to provide a heat insulating structure capable of reliably protecting tubular or linear parts such as various hydraulic hoses and various electric wires wired in the pipe from high temperatures.

  As a result of intensive studies to achieve the above object, the present inventors can achieve the above object by laminating, for example, a woven fabric or a non-woven fabric made of metal fibers between the metal thin film layer and the heat insulating layer. As a result, the present invention has been completed.

  That is, the present invention is a heat insulating structure having a multi-layer structure and having a metal thin film layer on the most surface side, wherein at least one heat conductive layer is disposed on the back surface side of the metal thin film layer, The side layer is a heat insulation layer, the heat diffusion coefficient of the heat conduction layer is larger than the heat diffusion coefficient of the heat insulation layer, and the ratio of the thickness of the heat insulation layer to the thickness of the heat conduction layer is 0.05 to 5 The structure of this heat insulation structure is a means for solving the above-described conventional problems.

  In the heat insulating structure of the present invention, since the heat conductive layer having a larger thermal diffusion coefficient than the heat insulating layer is disposed between the metal thin film layer and the heat insulating layer with the above-described thickness ratio, without impairing flexibility, The heat insulation performance will be dramatically improved.

  According to the heat insulation structure of the present invention, since it has the above-described configuration, for example, when used in an engine room of an automobile, piping in the engine room is realized while realizing reduction of heat insulation cost and improvement of heat insulation workability. An extremely excellent effect is obtained that it is possible to reliably protect tubular or linear parts such as various hydraulic hoses to be wired and various conductive wires from high temperatures.

  As shown in FIG. 1, the heat insulating structure of the present invention has a multilayer structure, and the most surface side (upper side in the drawing) is a metal thin film layer 1, and a heat conductive layer is formed on the back side of the metal thin film layer 1. 2 is arranged, and the layer on the backmost side is the heat insulating layer 3.

  Here, it is desirable that the heat conductive layer 2 disposed between the metal thin film layer 1 and the heat insulating layer 3 has a function of heat transfer and heat dissipation in the surface direction. Used a material having a thermal diffusion coefficient larger than that of the heat insulating layer 3. And if the ratio of the thickness of the heat insulation layer 3 to the thickness of the heat conductive layer 2 is less than 0.05, the heat insulation effect due to heat transfer in the surface direction becomes insufficient, while the heat insulation with respect to the thickness of the heat conductive layer 2 When the ratio of the thickness of the layer 3 exceeds 5, the temperature reduction effect due to heat transfer in the surface direction is not seen, so the ratio of the thickness of the heat insulating layer 3 to the thickness of the heat conductive layer 2 is 0.05 to 5. did.

  Moreover, in the heat insulation structure of this invention, it can be set as the structure currently formed in the heat conductive layer 2 with the woven fabric or nonwoven fabric which consists of metal fibers, In this case, as a metal fiber which comprises the heat conductive layer 2, iron is used. Metal fibers such as fibers, stainless fibers, copper fibers, and aluminum fibers can be used, and it is particularly desirable to use aluminum fibers.

  Furthermore, in the heat insulating structure of the present invention, the heat insulating layer 3 can be formed of a woven or non-woven fabric made of organic fibers. In this case, as the organic fibers constituting the heat insulating layer 3, polyester can be used. Organic fibers such as fibers, acrylic fibers, polypropylene fibers, nylon fibers, polyethylene fibers, aramid fibers, cotton fibers, and rayon fibers can be used, and polyester fibers are particularly preferable.

  Furthermore, in the heat insulating structure of the present invention, a metal foil or a metal vapor-deposited film can be used for the metal thin film layer 1, and as the metal foil, an aluminum foil, a stainless steel foil, a gold foil, a silver foil, a brass foil, , Copper foil and tin foil can be used, on the other hand, as the metal vapor deposition film, aluminum vapor deposition film, stainless steel vapor deposition film, gold vapor deposition film, silver vapor deposition film, brass vapor deposition film, copper vapor deposition film, A tin vapor deposition film can be used, and it is particularly desirable to use an aluminum foil as the metal foil and an aluminum vapor deposition film as the metal vapor deposition film.

  At this time, the metal foil or metal vapor deposition film as the metal thin film layer 1 is desirably a glossy one in order to efficiently reflect radiant heat, and the thickness thereof is not particularly limited. 5 to 50 μm is preferable.

  Furthermore, in the heat insulation structure according to the present invention, adjacent layers can be bonded with an adhesive. In this case, the type of the adhesive is not particularly limited, but it is naturally desirable to use a heat-resistant epoxy-based adhesive, urethane-based adhesive, or silicone-based adhesive. Note that a normal rubber adhesive, an acrylic adhesive, or an epoxy adhesive may be used unless used in an environment that is significantly exposed to high temperatures.

  Furthermore, in the heat insulating structure formed by laminating the metal thin film layer 1, the heat conductive layer 2, and the heat insulating layer 3, as shown in FIG. 2, the cross sectional area at the end 2a of the heat conductive layer 2 is changed to the cross sectional area at the central portion. In this case, it is possible to adopt a configuration in which a metal connection fitting 4 that contacts the end portion 2a of the heat conductive layer 2 is provided. As an automobile hose that can use a heat insulating structure including such a metal connection fitting 4, a high-pressure hydraulic hose 5 having caulking fittings (connection fitting 4) at both ends of the hose, for example, a brake hose, Although there are a clutch hose, a power steering hose, an air conditioner hose, etc., it is not particularly limited.

  The above-described heat insulating structure of the present invention can be used in the same form as a conventional heat insulating material, that is, used by wrapping around tubular or linear parts such as various hydraulic hoses and various electric wires. Further, it can be used by being formed into a sheet by pressing and sticking to a curved surface or an uneven surface of a tubular or linear part.

  Hereinafter, although one Example of the heat insulation structure of this invention is described in detail based on drawing, this invention is not limited to a following example.

[Example 1]
30 mm × 200 mm × 10 μm thick aluminum foil (metal thin film layer), 30 mm × 200 mm × 1.0 mm thick aluminum fiber nonwoven fabric (thermal conductive layer), 30 mm × 200 mm × 4.0 mm thick polyester fiber nonwoven fabric (Thermal insulation layer) was sequentially laminated, and adjacent layers were joined together with an epoxy adhesive to obtain a thermal insulation structure of this example. (See Figure 1)

[Example 2]
30 mm × 200 mm × 10 μm thick aluminum foil (metal thin film layer), 30 mm × 200 mm × 0.5 mm thick polyester fiber nonwoven fabric, and 30 mm × 200 mm × 0.5 mm thick aluminum fiber nonwoven fabric (heat conduction layer) Then, a 30 mm × 200 mm × 3.5 mm thick polyester fiber nonwoven fabric (heat insulating layer) was sequentially laminated, and adjacent layers were joined with an epoxy adhesive to obtain a heat insulating structure of this example.

[Example 3]
30 mm × 200 mm × 10 μm thick aluminum foil (metal thin film layer), 30 mm × 200 mm × 4.0 mm thick aluminum fiber nonwoven fabric (heat conductive layer), 30 mm × 200 mm × 1.0 mm thick polyester fiber nonwoven fabric (Thermal insulation layer) was sequentially laminated, and adjacent layers were joined together with an epoxy adhesive to obtain a thermal insulation structure of this example.

[Example 4]
In the heat insulation structure of Example 1, the thickness of the heat conductive layer at both ends (20 mm from the end face) is set to 5 mm (the cross-sectional area is increased), and the whole is formed into a cylindrical shape and connected to a metal pipe Wrapped around an automobile hose (EPDM hydraulic rubber hose; total length 200 mm, metal fitting length 15 mm) having a crimped metal fitting (connecting metal fitting) at both ends, and the center and both ends are fixed with a nylon band. did.

[Comparative Example 1]
A 30 mm × 200 mm × 10 μm thick aluminum foil and a 30 mm × 200 mm × 5.0 mm thick polyester fiber nonwoven fabric were laminated together to obtain a heat insulating structure of this comparative example.

[Comparative Example 2]
30 mm × 200 mm × 10 μm thick aluminum foil, 30 mm × 200 mm × 1.0 mm thick aluminum plate, and 30 mm × 200 mm × 4.0 mm thick polyester fiber nonwoven fabric are sequentially laminated to insulate this comparative example. A structure was obtained.

[Comparative Example 3]
30 mm × 200 mm × 10 μm thick aluminum foil, 30 mm × 200 mm × 1.0 mm thick polyester fiber non-woven fabric, and 30 mm × 200 mm × 4.0 mm thick aluminum fiber non-woven fabric were sequentially laminated, A heat insulating structure was obtained.

[Comparative Example 4]
30 mm × 200 mm × 10 μm thick aluminum foil, 30 mm × 200 mm × 0.5 mm thick aluminum fiber nonwoven fabric, and 30 mm × 200 mm × 4.5 mm thick polyester fiber nonwoven fabric are sequentially laminated, A heat insulating structure was obtained.

[Comparative Example 5]
30 mm × 200 mm × 10 μm thick aluminum foil, 30 mm × 200 mm × 4.8 mm thick aluminum fiber non-woven fabric, and 30 mm × 200 mm × 0.2 mm thick polyester fiber non-woven fabric are laminated in order. A heat insulating structure was obtained.

  Therefore, an industrial dryer is installed at the upper part of each center of the heat insulating structures of Examples 1 to 4 and Comparative Examples 1 to 5, so that the distance between the hot air outlet and the heat insulating structure is 200 mm. When the central part surface temperature and the central part inner layer surface temperature of the heat insulation structure when hot air was blown after adjustment to the temperature were measured with a thermocouple, the results shown in Table 1 were obtained.

  As shown in Table 1, it can be demonstrated that the heat insulating structures of Examples 1 to 4 have excellent heat insulating performance while maintaining flexibility as compared with the heat insulating structures of Comparative Examples 1 to 5. It was.

  Moreover, like the heat insulation structure of Example 4, by making the cross-sectional area in the edge part of a heat conductive layer larger than the cross-sectional area in a center part, higher heat dissipation is obtained, In addition, this heat conductive layer A higher heat-insulating effect can be obtained by bringing a metal connecting fitting into contact with the end of the metal plate.

It is sectional explanatory drawing which shows one Example of the heat insulation structure of this invention. (Example 1) It is sectional explanatory drawing which shows the other Example of the heat insulation structure of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metal thin film layer 2 Thermal conductive layer 2a End part of thermal conductive layer 3 Thermal insulation layer 4 Metal coupling metal fittings

Claims (8)

  A heat insulating structure having a multilayer structure and having a metal thin film layer on the outermost surface side, wherein at least one heat conductive layer is disposed on the rear surface side of the metal thin film layer, and the outermost layer is the heat insulating layer. And the heat diffusion coefficient of the heat conduction layer is larger than the heat diffusion coefficient of the heat insulation layer, and the ratio of the thickness of the heat insulation layer to the thickness of the heat conduction layer is 0.05 to 5. body.   The heat insulating structure according to claim 1, wherein the heat conductive layer is formed of a woven fabric or a nonwoven fabric made of metal fibers.   The heat insulation structure of Claim 2 which used the metal fiber of the heat conductive layer as the aluminum fiber.   The heat insulation structure according to any one of claims 1 to 3, wherein the heat insulation layer is formed of a woven fabric or a nonwoven fabric made of organic fibers.   The heat insulation structure as described in any one of Claims 1-4 which made the metal thin film layer the aluminum foil or the aluminum vapor deposition film.   The heat insulation structure as described in any one of Claims 1-5 which has joined adjacent layers with the adhesive agent.   The heat insulating structure according to any one of claims 1 to 6, wherein a cross-sectional area at an end portion of the heat conductive layer is larger than a cross-sectional area at a central portion.   The heat insulation structure as described in any one of Claims 1-7 which comprised the metal metal fitting and made this metal fitting contact the heat conductive layer.

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