The present invention relates to a multilayer heat-insulating material used in a spacecraft navigating the outer space or a mounted device thereof.
In a spacecraft navigating the outer space, particularly, a rocket or an artificial satellite, or a mounted device thereof, thermal management is important. The spacecraft in the outer space is exposed to sunlight in vacuum, and accordingly, a temperature of the exposed portion by radiation from sunlight is increased. Meanwhile, the unexposed portion from the sunlight releases heat due to the radiation, and the temperature thereof is decreased. Thus, a countermeasure of preventing heat input and maintaining a temperature around the mounted device is necessary, so that the temperature around the mounted device becomes a suitable operation temperature for an operating time of a rocket or an artificial satellite.
As one of such countermeasure, use of a multilayer heat-insulating material that is also referred to as a “thermal blanket” is known.
The multilayer heat-insulating material is formed by stacking heat-insulating sheets having a low emissivity. In such a multilayer heat-insulating material, thermal conduction due to a contact between the heat-insulating sheets is prevented and a heat-insulating effect is increased, by inserting a spacer between layers of the heat-insulating sheets.
By covering the spacecraft or the mounted device on the spacecraft with such a multilayer heat-insulating material, the heat input due to the radiation from the outside of the spacecraft is prevented and the heat release due to the radiation from the inside of the spacecraft is prevented. Therefore, it is possible to maintain a temperature environment of the spacecraft in a suitable operation temperature range.
Such a multilayer heat-insulating material is mounted on a spacecraft main body so as to cover the vicinity of the spacecraft or the mounted device on the spacecraft, and it may be necessary to repeat detachment or adjustment of a position of the rigged multilayer heat-insulating material, for an adjustment operation of the spacecraft. It is possible to efficiently perform such an operation, by applying detachable mounting means to the multilayer heat-insulating material. For example, as shown in
PTL 1 shown below discloses a method of mounting a thermal blanket on an attachment surface using a Hook-and-Loop fastener (Velcro (registered trademark) tape).
[PTL 1] Japanese Unexamined Patent Application Publication No. H9-152088
In the multilayer heat-insulating material, a case where the heat-insulating sheets are pressed against each other, causes a thermal leakage due to thermal conduction at that portion, and this is a reason for a deterioration in heat-insulating performance. The pressed portion is easily generated in the vicinity of the mounting means of the multilayer heat-insulating material. As shown in
Meanwhile, the multilayer heat-insulating material 102 is stacked and formed by inserting the spacer 102b between the heat-insulating sheets 102a, otherwise, the heat-insulating sheets may be separated from each other, and accordingly, it is hard to handle the multilayer heat-insulating material. In a case of integrating the heat-insulating sheets by sewing, in order for ease of handling of this, the deformation to a desired shape is hardly performed. For example, in a case of covering the mounting device on a spacecraft, the deformation at a predetermined portion along a three-dimensional shape thereof may not be easily performed. In contrast, as shown in
The invention is made in view of such circumstances, and an object of the invention is to provide a multilayer heat-insulating material that prevents a deterioration in heat-insulating performance in the vicinity of mounting means and makes deformation to a desired shape easy.
In the invention, the following means are used for achieving the objects described above.
That is, there is provided a multilayer heat-insulating material according to one aspect of the invention, including: a heat-insulating member in which a heat-insulating sheet and a spacer are stacked; an engagement sheet provided adjacent to the heat-insulating member; a heat-insulating member engagement tool that penetrates the heat-insulating member and the engagement sheet and engages the heat-insulating member and the engagement sheet with each other; and a mounting member that is provided on the engagement sheet and is detachable from a mounting target, in which the heat-insulating member engagement tool performs the engagement so that each layer of the heat-insulating member is not adhered to each other.
The heat-insulating member and the engagement sheet are engaged so that the heat-insulating sheet and the spacer are not adhered to each other by the heat-insulating member engagement tool. The heat-insulating member and the engagement sheet are detachably attached to the mounting target by the mounting member provided on the engagement sheet. The mounting member is provided on the engagement sheet, and accordingly, is not directly attached to the heat-insulating member. The heat-insulating member engagement tool performs the engagement so that each layer of the heat-insulating member is not adhered to each other, and accordingly, it is possible to avoid occurrence of a deterioration in heat-insulating performance due to adhesion of each layer of the heat-insulating member.
In the multilayer heat-insulating material according to the one aspect of the invention, the heat-insulating member engagement tool includes a shank that penetrates the heat-insulating member and the engagement sheet in a stacking direction, and one pair of engagement portions that are provided on both ends of the shank, and a length of the shank is longer than a thickness, in a case where the heat-insulating member and the engagement sheet are in contact with each other, in a state where a load is not applied in the stacking direction.
By setting the length of the shank of the heat-insulating member engagement tool to be longer than the thickness, in a case where the heat-insulating member and the engagement sheet are in contact with each other, in a state where a load is not applied in the stacking direction, it is possible to perform the engagement so that each layer of the heat-insulating member is not adhered.
In the multilayer heat-insulating material according to the one aspect of the invention, the engagement sheet is a net-shaped or porous sheet.
By using a net-shaped or porous sheet as the engagement sheet, it is possible to prevent a weight increase while preventing thermal conduction.
In the multilayer heat-insulating material according to the one aspect of the invention, the engagement sheet includes a folding portion capable of forming a folding line along a predetermined direction.
The folding portion is provided on the engagement sheet, and the folding line is formed along the predetermined direction. Therefore, it is possible to mount the multilayer heat-insulating material in accordance with the shape of the mounting target.
In the multilayer heat-insulating material according to the one aspect of the invention, the engagement sheet includes a plurality of engagement sheet pieces, and a sheet connection portion that connects the engagement sheet pieces to each other, and the folding portion is formed by the sheet connection portion.
The engagement sheet is divided into the plurality of engagement sheet pieces, and the sheet connection portion that connects engagement sheet piece to each other is provided. The folding portion is formed by this sheet connection portion. As the sheet connection portion, for example, an adhesion tape or a resin film is used.
In the multilayer heat-insulating material according to the one aspect of the invention, the plurality of engagement sheet pieces have a shape corresponding to each surface of the mounting target.
By setting each engagement sheet piece to have a shape corresponding to each surface of the mounting target, it is possible to mount the multilayer heat-insulating material according to the shape of the mounting target.
It is possible to prevent a deterioration in heat-insulating performance in the vicinity of mounting means of the multilayer heat-insulating material and make deformation to a desired shape easy.
Hereinafter, a multilayer heat-insulating material according to a first embodiment of the invention will be described with reference to the drawings.
As shown in
The heat-insulating member 2 is formed by stacking 10 to 20 layers of the heat-insulating sheet 2a with spacers 2b interposed therebetween. As an example of the heat-insulating sheet, a film having a low emissivity, for example, or a layer obtained by performing vapor deposition of metal on a resin film having a thickness of 10 to 20 micrometers is used. As a suitable example, a layer obtained by performing vapor deposition of metal (Al, Ag, or Au) on a Kapton film having a thickness of 10 to 20 micrometers is used. The emissivity of light or electromagnetic waves is improved by performing the vapor deposition of metal, and therefore, in a case where the heat-insulating member is mounted on a mounting target 9 (spacecraft such as a rocket or an artificial satellite or a device mounted on a spacecraft) as the multilayer heat-insulating material, heat input due to radiation from the outside is prevented and heat release to the outside due to the radiation from the inside is prevented. As an example of the spacer 2b, a net-shaped member or a porous sheet-shaped member formed of a heat-insulating material is used, and particularly, a member formed of a material having a lower thermal conductivity than that of a film used in the heat-insulating sheet 2a is preferable.
The engagement sheet 3 is fastened by the mounting member 4 and a suture 6. The mounting member 4 is used in a case of mounting the multilayer heat-insulating material 1 on the mounting target 9. For example, a mounting member 8 to be paired is provided on a surface of the mounting target 9, and the mounting member 4 is mounted on the mounting member 8. The mounting member 4 is not fastened to the heat-insulating member 2. The mounting member 4 is desirably repeatedly detachable mounting means, and is particularly desirable to be detached by an operation from the outside of the multilayer heat-insulating material 1. A Hook-and-Loop fastener is used as an example of the mounting member 4, and a fastener such as a snap or a hook can also be used. The engagement sheet 3 is repeatedly detachable from a spacecraft or a device mounted on a spacecraft by the mounting member 4. The engagement sheet 3 has a strength so that the engagement sheet is not damaged, even in a case where the detachment is repeated. As a suitable example of the engagement sheet 3, a material obtained by proceeding styrene, polyethylene, polypropylene, polytetrafluoroethylene, or a foaming body thereof in a sheet shape is used. As the other suitable example of the engagement sheet 3, a net-shaped sheet or a porous sheet formed of styrene, polyethylene, polypropylene, or polytetrafluoroethylene is used.
The heat-insulating member engagement tool 5 is dispersively provided in an in-plane direction of a laminate formed of the heat-insulating member 2 and the engagement sheet 3. The heat-insulating member engagement tool 5 includes a shank 5a, and a pair of engagement portions 5b and 5c provided on both ends of the shank 5a. The engagement portion 5b is provided on the outer side of the engagement sheet 3 of the laminate, and the engagement portion 5c is provided on the outer side of the heat-insulating member 2 of the laminate. As the heat-insulating member engagement tool 5, for example, a tag pin attached with a tag gun is used. As a material of the heat-insulating member engagement tool 5, nylon is used, for example.
The shank 5a is provided to penetrate each layer (stacked heat-insulating sheets 2a and spacers 2b) of the heat-insulating members 2 and the engagement sheet 3. The heat-insulating member engagement tool 5 is formed so that a length of the shank 5a is equal to or greater than a sum of a thickness of the stacked heat-insulating members 2 and a thickness of the engagement sheet 3. Accordingly, an inter-layer distance of each layer of the heat-insulating member 2 is not greatly narrowed by the heat-insulating member engagement tool 5, and the layers are not adhered to each other. Accordingly, a deterioration in heat-insulating performance due to the pressing of each layer of the heat-insulating member does not occur. The sum of the thickness of the stacked heat-insulating members 2 and the thickness of the engagement sheet 3 means a thickness, in a case where the heat-insulating members are in contact with each other, in a state where a load is not applied in the stacking direction thereof, that is, a thickness in a state where the heat-insulating members 2 and the engagement sheet 3 are stacked by dead load.
The shank 5a does not bind each layer of the heat-insulating member 2 and the engagement sheet 3 in the stacking direction in the penetration portion of the laminate, and a relative position of the shank 5a, and each layer of the heat-insulating member 2 and the engagement sheet 3 can be changed in an extending direction of the shank 5a.
The engagement portions 5b and 5c are respectively formed so that a portion having a diameter longer than a diameter of a hole formed at the penetration portion of the laminate penetrated by the shank 5a is provided in a direction orthogonal to the shank 5a. For example, the engagement portions 5b and 5c respectively have a rod shape or a plate shape, are connected to the shank 5a at each center in a longitudinal direction, and extends longer than a diameter of the hole in a direction orthogonal to the shank 5a from the connection portion. Therefore, the heat-insulating member engagement tool 5 is prevented from falling from the laminate. The engagement portions 5b and 5c are respectively formed to have a material and a shape so that an engagement state can be maintained, even in a case where a force is applied to the heat-insulating member engagement tool 5, at the time of attachment or detachment of the multilayer heat-insulating material 1.
The heat-insulating member engagement tool 5 is dispersively provided in a plane direction of the laminate. For example, as shown in
As described above, the heat-insulating member 2 is engaged to the engagement sheet 3 by the heat-insulating member engagement tool 5, and the engagement sheet 3 is mounted on the mounting target 9 by the mounting member 4, and accordingly, it is possible to prevent reduction of heat-insulating performance by pressing of each layer of the heat-insulating member 2.
Next, a manufacturing method of a multilayer heat-insulating material according to the embodiment will be described.
First, as shown in
Next, as shown in
Next, as shown in
The inserted heat-insulating member engagement tool 5 penetrates the heat-insulating member 2 and the engagement sheet 3, and the engagement portion 5b on a lower side of the engagement sheet 3 is deformed in a shape extending longer than a diameter of the hole in a direction orthogonal to the shank 5a from the connection portion on the connection portion with the shank 5a. Accordingly, the heat-insulating member engagement tool 5 is prevented from falling from the laminate, and the heat-insulating member 2 and the engagement sheet 3 are engaged with each other. For example, in a case of using the heat-insulating member engagement tool 5 including the engagement portion 5b formed of a material having elasticity and orthogonal to the shank 5a, the engagement portion 5b may be fixed in an overlapped state so as to substantially parallel to the shank 5a, the heat-insulating member engagement tool may be inserted and penetrate so as to penetrate the heat-insulating members 2 and the engagement sheet 3, the fixed state may be released on the lower portion of the engagement sheet 3, the shape may be recovered by the elasticity of the heat-insulating member engagement tool 5, and the heat-insulating members 2 and the engagement sheet 3 may be engaged. In addition, by forming the shank 5a in a smooth surface shape in the extending direction of the shank, each layer of the laminate can be slidably move along the shank 5a and can be easily deformed in a desired shape.
Step 1-3 and Step 1-4 are repeated, the predetermined number of heat-insulating member engagement tools 5 are dispersively provided in a plane direction of the laminate, and accordingly, the heat-insulating member 2 is engaged with the engagement sheet 3 and the multilayer heat-insulating material 1 is integrated. For example, in a case where the heat-insulating member 2 has a shape of polygon in a plan view, one or more heat-insulating member engagement tools 5 may be dispersively provided in the vicinity of each apex thereof or dispersively provided on a peripheral edge portion along a part or the entirety of each side of the polygon.
As shown in
As shown in
As another modification example of Step 1-1, as shown in
Hereinafter, a multilayer heat-insulating material according to a second embodiment of the invention will be described with reference to the drawings.
A multilayer heat-insulating material 11 according to the embodiment is shown in
As shown in
The engagement sheet 13 is formed of a plurality of engagement sheet pieces 13a, and flexible sheet connection portion (folding portion) 13b connecting the plurality of engagement sheet pieces to each other. As shown in
The engagement sheet piece 13a is a sheet piece on a flat plate formed of a material such as styrene, polyolefin, polypropylene, or polytetrafluoroethylene, and having a rigidity. In a case of deforming the multilayer heat-insulating material 11 in accordance with the shape of the mounting target 9, it is desirable to determine a thickness or a material so that the engagement sheet 13 maintains the shape and engages the engagement portions 5b and 5c of the heat-insulating member engagement tool 5 without being broken. Each of the engagement sheet pieces 13a has a shape of at least one of surfaces configuring a development view developing the predetermined three-dimensional shape 13′ surrounding the mounting target 9. The thickness or the material of the engagement sheet 13 may be locally changed.
The sheet connection portion 13b is a flexible material connecting a peripheral edge portion and a peripheral edge portion of the engagement sheet piece 13a and the engagement sheet piece 13a is connected so as to change a relative position. For example, as an example of the sheet connection portion 13b, an adhesion tape or a resin film attached to the peripheral edge portion of the engagement sheet piece 13a is used. The sheet connection portion 13b is formed to be more flexible than the engagement sheet piece 13a having a rigidity. Therefore, in a case of deforming the multilayer heat-insulating material 11 along the mounting target 9, the laminate formed of the heat-insulating member 12 and the engagement sheet 13 can be easily folded at a position of the sheet connection portion 13b. The sheet connection portion 13b preferably has a structure in which the sheet connection portion 13b is mounted on the inner side of the engagement sheet 13 in a folding direction.
The heat-insulting member 12 is formed by stacking 10 to 20 layers of the heat-insulating sheet 12a with spacers 12b interposed therebetween, in the same manner as in the heat-insulting member 2 of the first embodiment. The heat-insulating member 12 is greater than the engagement sheet 13 in a plan view, and has a shape of covering the entirety of the engagement sheet in a state where the engagement sheet 13 is folded to be inner side. For example, as shown in
The heat-insulating member engagement tool 5 is dispersively provided in the in-plane direction of the laminate formed of the heat-insulating member 12 and the engagement sheet 13. The shank 5a of the heat-insulating member engagement tool 5 is provided to penetrate each layer (stacked heat-insulating sheets 12a and spacers 12b) of the heat-insulating members 12 and the engagement sheet 13. The heat-insulating member engagement tool 5 is formed so that a length of the shank 5a is equal to or greater than a sum of a thickness of the stacked heat-insulating members 12 and a thickness of the engagement sheet 13. Accordingly, an inter-layer distance of each layer of the heat-insulating member 2 is not greatly narrowed by the heat-insulating member engagement tool 5, and accordingly, a deterioration in heat-insulating performance due to the pressing of each layer of the heat-insulating member does not occur. The sum of the thickness of the stacked heat-insulating members 12 and the thickness of the engagement sheet 13 means a thickness, in a case where the heat-insulating members are in contact with each other, in a state where a load is not applied in the stacking direction thereof, that is, a thickness in a state where the heat-insulating members 12 and the engagement sheet 13 are stacked by dead load.
In a case where the thickness of the engagement sheet 13 is locally different, a length of the shank 5a may be locally changed in advance according thereto. The shank 5a does not bind each layer of the heat-insulating member 12 and the engagement sheet 13 in the stacking direction in the penetration portion of the laminate, and a relative position of the shank 5a, and each layer of the heat-insulating member 12 and the engagement sheet 13 can be changed in an extending direction of the shank 5a. The engagement portions 5b and 5c are respectively formed so that a portion having a diameter longer than a diameter of a hole formed at the penetration portion of the laminate penetrated by the shank 5a is provided in a direction orthogonal to the shank 5a. For example, the engagement portions 5b and 5c respectively have a rod shape or a plate shape, are connected to the shank 5a at each center in a longitudinal direction, and extends longer than a diameter of the hole in a direction orthogonal to the shank 5a from the connection portion. The engagement portions 5b and 5c are respectively formed to have a material and a shape so that an engagement state can be maintained, even in a case where a force is applied to the heat-insulating member engagement tool 5, at the time of attachment or detachment of the multilayer heat-insulating material 11.
It is suitable that the heat-insulating member engagement tool 5 is dispersively provided in a plane direction so as to penetrate the peripheral edge portion of the engagement sheet piece 13a. The position for providing the heat-insulating member engagement tool 5 is determined by assuming a state where the engagement sheet 13 is folded by the sheet connection portion 13b to form the predetermined three-dimensional shape 13′ surrounding the mounting target 9. For example, as shown in
Next, the manufacturing method of the multilayer heat-insulating material according to the embodiment will be described.
First, the predetermined three-dimensional shape 13′ surrounding the mounting target 9 is assumed and a development view developing this three-dimensional shape 13′ is drawn. Each engagement sheet piece 13a is formed in a shape shown in
Next, as shown in
Next, as shown in
Next, as shown in
The inserted heat-insulating member engagement tool 5 penetrates the heat-insulating member 12 and the engagement sheet 13, and the engagement portion 5b on a lower side of the engagement sheet 13 is deformed in a shape extending longer than a diameter of the hole in a direction orthogonal to the shank 5a from the connection portion on the connection portion with the shank 5a. Accordingly, the heat-insulating member engagement tool 5 is prevented from falling from the laminate, and the heat-insulating member 12 and the engagement sheet 13 are engaged with each other. By forming the shank 5a in a smooth surface shape in the extending direction of the shank, each layer of the laminate can be slidably move along the shank 5a and can be easily deformed in a desired shape. (Step 2-5)
Step 2-4 and Step 2-5 are repeated, the predetermined number of heat-insulating member engagement tools 5 are dispersively provided in a plane direction of the laminate, and accordingly, the heat-insulating member 12 is engaged with the engagement sheet 13 and the multilayer heat-insulating material 11 is integrated. As a suitable example, first, the heat-insulating member engagement tool 5 is provided on four corners of the engagement sheet piece 13a corresponding to the top board of the three-dimensional shape 13′, and the heat-insulating member engagement tool 5 is also provided on the peripheral edge portion (peripheral portion on a side opposite to the sheet connection portion 13b) of each engagement sheet piece 13a connected at the peripheral edge portion. Therefore, it is possible to integrate the multilayer heat-insulating material, regardless of the change of the relative position during the folding.
In a case where the engagement sheet 13 is folded to have a shape of a protrusion to the outer side in the inner side, the position for forming the heat-insulating member engagement tool 5 is determined, by assuming that the layer of the heat-insulating member 12 on the outer side has a radius of curvature greater than that of the layer on the inner side. As a suitable example, as shown in
The integrated multilayer heat-insulating material 11 is mounted on the mounting target 9 by connecting the mounting member 4 fastened to the engagement sheet 13 and the mounting member 8 on the facing side. At the time of the mounting, the engagement sheet 13 is folded so as to form the predetermined three-dimensional shape 13′, and accordingly, the multilayer heat-insulating material 11 is deformed in accordance with the shape of the mounting target 9. The positions and the number of mounting member 4 and the mounting member 8 are suitably selected in accordance with the shape of the mounting target 9.
In the same manner as in the manufacturing method of the multilayer heat-insulating material 1 according to the first embodiment, Step 2-2 may further include a step of forming the heat-insulating member 12 by stacking the heat-insulating sheets 12a and the spacers 12b and integrating by sewing the peripheral edge portions thereof (Step 2-2′). In this step, it is suitable that the heat-insulating member 12 is formed to be greater than the engagement sheet 13, and the peripheral edge portions to be sewn are extended to the outer side of the engagement sheet 13 in the plane direction. In addition, after completing the rigging, a portion extended from the engaged sheet may be cut for each sewn portion. In this case, a contact state of each layer of the heat-insulating member generated by the sewn peripheral edge portion is alleviated.
In the same manner as in the manufacturing method of the multilayer heat-insulating material 1 according to the first embodiment, Step 2-2 may further include a step of forming the heat-insulating member 12 by stacking the heat-insulating sheets 12a and the spacers 12b, and dispersively providing a plurality of heat-insulating member peripheral edge portion engagement tools 7 on the peripheral edge portions, for integrating (Step 2-2″). The heat-insulating member peripheral edge portion engagement tool 7 is inserted from a surface of the upper side of the heat-insulating member 12 so as to penetrate each layer of the heat-insulating member 12, and the heat-insulating member peripheral edge portion engagement tool engagement portion 7b on a lower side of the heat-insulating member 2 is deformed in a shape extending longer than a diameter of the hole in a direction orthogonal to the heat-insulating member peripheral edge portion engagement tool shank 7a from the connection portion on the connection portion with the heat-insulating member peripheral edge portion engagement tool shank 7a. This is repeated, and the predetermined number of heat-insulating member peripheral edge portion engagement tools 7 are dispersively provided in the plane direction of the heat-insulating member 2, for integrating the heat-insulating members 2. As the heat-insulating member peripheral edge portion engagement tool 7, the same tool as the heat-insulating member engagement tool 5 described above is used, and the heat-insulating member peripheral edge portion engagement tool may be inserted into the heat-insulating members 12 by the same means as the heat-insulating member engagement tool 5.
In the embodiments described above, the plurality of engagement sheet pieces 13a are connected by the sheet connection portion 13b and the engagement sheet 13 is folded by the sheet connection portion 13b, but the engagement sheet 13 may not be divided and a line of folding may be drawn with scratch or hollow.
1, 11: multilayer heat-insulating material
2, 12: heat-insulating member
2
a,
12
a: heat-insulating sheet
2
b,
12
b: spacer
3, 13: engagement sheet
4: mounting member
5, 5′: heat-insulating member engagement tool
5
a,
5
a′: shank
5
b,
5
c: engagement portion
6: suture
7: heat-insulating member peripheral edge portion engagement tool
7
a: heat-insulating member peripheral edge portion engagement tool shank
7
b,
7
c: heat-insulating member peripheral edge portion engagement tool engagement portion
8: mounting member
9: mounting target
13
a: engagement sheet piece
13
b: sheet connection portion (folding portion)
Number | Date | Country | Kind |
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2017-114553 | Jun 2017 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2018/021380 | 6/4/2018 | WO | 00 |