Structure for spacecraft and support member for spacecraft
The spacecraft structure combines a heat-insulating and reinforcing member with different expansion coefficients to maintain structural integrity and prevent heat transfer between temperature-differentiated components, addressing the challenges of conventional support members.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-08-20
- Publication Date
- 2026-03-05
AI Technical Summary
Spacecraft structures face the challenge of maintaining structural integrity under external forces while preventing heat transfer between components with different temperatures, as conventional support members may buckle or increase heat penetration into low-temperature parts.
A spacecraft structure with a heat-insulating support member and a reinforcing member having a higher linear expansion coefficient than the insulating member, where the reinforcing member contacts the connecting ends in a room-temperature environment, thermally isolating from the ends in a low-temperature environment to prevent heat transfer and maintain structural integrity.
The structure ensures resistance to external forces and prevents heat transfer into low-temperature parts, maintaining temperature differences and structural integrity in varying environmental conditions.
Smart Images
Figure 2026036490000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a spacecraft structure and a spacecraft support member. [Background technology]
[0002] As described in Patent Document 1, a conventional absorption refrigerator is known that includes an insulated housing, a cooling system attached to the rear side of the insulated housing, and a back panel that covers the rear side of the insulated housing. The back panel is provided to prevent contact with high-temperature parts of the cooling system. Heat dissipation holes are provided at the top and bottom ends of the back panel. Hot air dissipated from the cooling system rises through a duct between the insulated housing and the back panel, and is circulated through the heat dissipation holes. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-160314 Summary of the Invention [Problem to be solved by the invention]
[0004] In the absorption refrigerator described above, the back panel prevents contact with high-temperature parts and also provides a heat dissipation effect, but the structural role of the back panel is unclear.
[0005] In various structures mounted on spacecraft such as artificial satellites, there may be temperature differences between multiple components. A structure is conceivable in which support members provided between these components connect and support these components. Because it is expected that external forces such as compressive loads will be applied to the structure, the support members are required to have a certain level of strength. Meanwhile, the support members may form a heat transfer path between these components. For example, if the cross-sectional area of the support members is increased to ensure their strength, there is a risk that the amount of heat that penetrates into the low-temperature portion through the support members will increase. Therefore, there is a need for a structure that ensures resistance to external forces while not increasing the amount of heat that penetrates into the low-temperature portion.
[0006] The present invention aims to provide a spacecraft structure and a spacecraft support member that, when the structure has multiple parts with different temperatures, ensures resistance to external forces while preventing an increase in the amount of heat entering low-temperature parts. [Means for solving the problem]
[0007] A spacecraft structure according to one embodiment of the present invention comprises a high-temperature portion, a low-temperature portion arranged spaced apart from the high-temperature portion and capable of becoming colder than the high-temperature portion, a first connecting end connected to the high-temperature portion, a second connecting end connected to the low-temperature portion, an insulating support member extending longitudinally between the first connecting end and the second connecting end, and a reinforcing member provided on the outer periphery of the insulating support member and extending longitudinally, such that, in a room temperature environment, the high-temperature side end located on the high-temperature portion side contacts the first connecting end and the low-temperature side end located on the low-temperature portion side contacts the second connecting end, and the reinforcing member is made of a material having a linear expansion coefficient greater than that of the insulating support member.
[0008] According to this spacecraft structure, in a room-temperature environment where an external force such as a compressive load is expected to be applied, the high-temperature end of the reinforcing member contacts the first connecting end, and the low-temperature end contacts the second connecting end. In this state, the reinforcing member contributes to improving the support strength. The cooperation of the insulating support member and the reinforcing member ensures resistance to external forces. For example, in a conventional support member that does not include a reinforcing member (consisting only of the insulating support member), buckling or damage may occur in the insulating support member when a compressive load is applied, for example. However, in the spacecraft structure described above, buckling or damage to the insulating support member is prevented. Furthermore, because the linear expansion coefficient of the reinforcing member is greater than that of the insulating support member, in a predetermined low-temperature environment that is lower than room temperature, such as outer space, the reinforcing member contracts more than the insulating support member. Either the high-temperature end separates from the first connecting end, or the low-temperature end separates from the second connecting end (or both separations occur). As a result, the reinforcing member is thermally isolated from the high-temperature and low-temperature sections and does not form a heat transfer path, so the amount of heat entering the low-temperature section is the same as the amount of heat entering through only the insulating support member, and does not increase by providing the reinforcing member.
[0009] In the spacecraft structure, the low-temperature end may be connected to the second connection end, and the high-temperature end may not be connected to the first connection end and may be separable from the first connection end. With this configuration, the high-temperature end is separated from the first connection end in a predetermined low-temperature environment. This effectively prevents heat from entering from the high-temperature portion.
[0010] In the spacecraft structure, the heat insulating support member may be a cylindrical body made of resin and extending in the longitudinal direction. With this configuration, it is possible to reduce heat penetration into the low-temperature part through the heat insulating support member while ensuring the strength required in space, etc.
[0011] In the spacecraft structure, the reinforcing member may be a cylindrical body made of metal or resin that surrounds the heat insulating support member and extends in the longitudinal direction. The cylindrical structure makes it easy to reinforce the heat insulating support member with a simple structure. Furthermore, if the reinforcing member is made of metal, it is easy to increase the difference in linear expansion coefficient between the reinforcing member and the heat insulating support member.
[0012] In the spacecraft structure, the first and second connection ends may be connected to the high-temperature and low-temperature parts by pin joints, respectively. With this configuration, even if the high-temperature or low-temperature part experiences large thermal contraction, three rotational components out of the six degrees of freedom are free, making it easy to release thermal strain.
[0013] Another aspect of the present invention provides a support member for a spacecraft, comprising a first connecting end and a second connecting end provided at both longitudinal ends, an insulating support member extending longitudinally between the first connecting end and the second connecting end, and a reinforcing member provided on the outer periphery of the insulating support member, extending longitudinally, and having one longitudinal end in contact with the first connecting end and the other longitudinal end in contact with the second connecting end in a room temperature environment, wherein the reinforcing member is made of a material having a linear expansion coefficient greater than that of the insulating support member.
[0014] According to this spacecraft support member, in a room-temperature environment where an external force such as a compressive load is expected to be applied, one end of the reinforcing member contacts the first connection end, and the other end contacts the second connection end. In this state, the reinforcing member contributes to improving the support strength. Cooperation between the heat-insulating support member and the reinforcing member ensures resistance to external forces and prevents buckling or damage to the heat-insulating support member. Furthermore, because the linear expansion coefficient of the reinforcing member is greater than that of the heat-insulating support member, in a predetermined low-temperature environment that is lower than room temperature, such as outer space, the reinforcing member contracts more than the heat-insulating support member. One end separates from the first connection end, or the other end separates from the second connection end (or both separations occur). Even if there is a temperature difference between the first connection end and the second connection end, the reinforcing member is thermally isolated from at least one of the first connection end and the second connection end, and does not form a heat transfer path. Therefore, the amount of heat transfer through the entire spacecraft support member is equivalent to the amount of heat transfer through only the heat insulating support member, and is not increased by providing the reinforcing member.
[0015] According to yet another aspect of the present invention, a support member for a spacecraft comprises a first connecting end and a second connecting end provided at both ends in the longitudinal direction, an insulating support member extending in the longitudinal direction between the first connecting end and the second connecting end, and a reinforcing member provided on the outer periphery of the insulating support member, extending in the longitudinal direction, and having one longitudinal end in contact with the first connecting end and the other longitudinal end in contact with the second connecting end in a room temperature environment, and at least one of the one end or the other end of the reinforcing member is configured to be separated from at least one of the first connecting end or the second connecting end in a predetermined low-temperature environment that is lower than room temperature.
[0016] According to this spacecraft support member, in a room-temperature environment where an external force such as a compressive load is expected to be applied, one end of the reinforcing member contacts the first connection end, and the other end contacts the second connection end. In this state, the reinforcing member contributes to improving the support strength. Cooperation between the heat-insulating support member and the reinforcing member ensures resistance to external forces and prevents buckling or damage to the heat-insulating support member. Furthermore, in a predetermined low-temperature environment that is lower than room temperature, such as outer space, one end of the reinforcing member separates from the first connection end, or the other end of the reinforcing member separates from the second connection end (or both separations occur). Even if there is a temperature difference between the first connection end and the second connection end, the reinforcing member is thermally isolated from at least one of the first connection end and the second connection end, and does not form a heat transfer path. Therefore, the amount of heat transfer throughout the entire spacecraft support member is equivalent to the amount of heat transfer through the heat-insulating support member alone and is not increased by providing the reinforcing member. [Effects of the Invention]
[0017] According to some aspects of the present invention, when a spacecraft structure has a high-temperature portion and a low-temperature portion, the heat insulating support member and the reinforcing member cooperate to ensure resistance to external forces in a room-temperature environment. Furthermore, even in a predetermined low-temperature environment, the amount of heat entering the low-temperature portion does not increase. [Brief explanation of the drawings]
[0018] [Figure 1] FIG. 1 is a perspective view showing a spacecraft structure according to one embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view showing the spacecraft support member in FIG. [Figure 3] FIG. 3 is a cross-sectional view of the spacecraft support member of FIG. [Figure 4] FIG. 4 is a cross-sectional view of the vicinity of the second connection end and the low-temperature end of the spacecraft support member. [Figure 5] FIG. 5 is a cross-sectional view of the first connection end and the high temperature end of the spacecraft support member. [Figure 6]FIG. 6 is a cross-sectional view that schematically shows the positional relationship of each member of the spacecraft support member in a room temperature environment. [Figure 7] FIG. 7 is a cross-sectional view showing a schematic diagram of the positional relationship among the components of the spacecraft support member in a predetermined low-temperature environment. DETAILED DESCRIPTION OF THE INVENTION
[0019] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate explanations will be omitted. The drawings are created for explanatory purposes and are drawn to particularly emphasize the portions to be described. Therefore, the dimensional proportions of the components in the drawings do not necessarily correspond to the actual proportions.
[0020] First, with reference to FIG. 1, a spacecraft structure S according to one embodiment of the present invention will be described. As shown in FIG. 1, the spacecraft structure S is a structure mounted on an unmanned spacecraft such as an artificial satellite. The spacecraft structure S is a structure for use at low temperatures in space. There are no particular limitations on the application or use of the spacecraft structure S. The spacecraft structure S is used in a predetermined low-temperature environment that is lower than room temperature, such as outer space. The temperature referred to as the "predetermined low-temperature environment" is not particularly limited, but refers to an environment with a large temperature difference from room temperature (for example, a temperature difference of 250 K or more) that can cause a gap g (see FIG. 7) due to thermal contraction of the reinforcing sleeve 20, which will be described later. The "predetermined low-temperature environment" may also refer to an extremely low-temperature environment (for example, an environment below 4 K). However, the "predetermined low-temperature environment" may be any temperature lower than room temperature. The "room temperature" refers to a general temperature in the environment in which the spacecraft structure S is manufactured and used on Earth, and may refer to a temperature of, for example, about 0°C to 30°C (naturally, this varies depending on the region).
[0021] The spacecraft structure S includes a high-temperature portion P1 and a low-temperature portion P2 that can be cooled below the high-temperature portion P1. The temperature difference between the high-temperature portion P1 and the low-temperature portion P2 is, for example, about 3 to 50 K. The low temperature portion P2 is maintained at a low temperature by connecting a refrigerator (not shown) or the like. If the spacecraft structure S is an observation satellite or the like, various sensors (measuring devices, etc.) may be provided in the low-temperature portion P2. It is desirable to maintain a predetermined temperature difference between the high-temperature portion P1 and the low-temperature portion P2. Therefore, the low-temperature portion P2 is disposed at a distance from the high-temperature portion P1. That is, the opposing surface P2a (lower surface in the figure) of the low-temperature portion P2 and the opposing surface P1a (upper surface in the figure) of the high-temperature portion P1 are separated by a predetermined distance. In the example shown in FIG. 1, the high-temperature portion P1 and the low-temperature portion P2 have a simplified rectangular shape, but the shapes and structures of the high-temperature portion P1 and the low-temperature portion P2 are not particularly limited.
[0022] A plurality of spacecraft support members 1 are provided between the high-temperature section P1 and the low-temperature section P2. For example, a plurality of rod-shaped spacecraft support members 1 are provided in a V-shape (or like a pair of hypotenuses of an isosceles trapezoid) on each side of the high-temperature section P1 and the low-temperature section P2. This forms a support mechanism with a truss structure. In the example shown in FIG. 1, four side mounting plates 8 provided on the four sides of the low-temperature section P2 and four corner mounting plates 9 provided on the four corners of the high-temperature section P1 are connected by eight spacecraft support members 1. The number of spacecraft support members 1 is not limited to the above. The length of each spacecraft support member 1 may be set appropriately depending on the positions and lengths of both ends to be supported.
[0023] Each spacecraft support member 1 has a first connection end 3 connected to the high-temperature part P1 and a second connection end 4 connected to the low-temperature part P2. In this embodiment, pins (not shown) are inserted into pin holes 3c, 4c (see FIG. 3) of the first connection end 3 and the second connection end 4, and these pins are fixed to the side mounting plate 8 or the corner mounting plate 9. With this pin joint structure, the first connection end 3 and the second connection end 4 are connected to the high-temperature part P1 and the low-temperature part P2, respectively.
[0024] Next, the spacecraft support member 1 of this embodiment will be described in detail with reference to Figures 2 to 5. As shown in Figures 2 and 3, the spacecraft support member 1 is a rod-shaped member (or a bar-shaped member) extending straight in the longitudinal direction L. The spacecraft support member 1 includes a first connection end 3 and a second connection end 4 provided at both ends in the longitudinal direction L, a heat insulating support member 10 (see Figure 3) extending in the longitudinal direction L between the first connection end 3 and the second connection end 4, and a reinforcing sleeve (reinforcing member) 20 provided on the outer periphery of the heat insulating support member 10 and extending in the longitudinal direction L. The first connection end 3, the second connection end 4, the heat insulating support member 10, and the reinforcing sleeve 20 are arranged concentrically with respect to a central axis A extending in the longitudinal direction L.
[0025] Each of the first connection end 3 and the second connection end 4 is an end fitting for a pin joint connection. Each of the first connection end 3 and the second connection end 4 is made of, for example, resin. Note that each of the first connection end 3 and the second connection end 4 may also be made of metal.
[0026] As shown in FIG. 3 , the heat insulating support member 10 is a cylindrical body extending in the longitudinal direction L. More specifically, the heat insulating support member 10 has a cylindrical shape with a fixed outer shape. The heat insulating support member 10 is made of resin, such as FRP (Fiber Reinforced Plastics). To reduce heat penetration from the high-temperature part P1 to the low-temperature part P2, a highly rigid, lightweight material with excellent heat insulating properties is used for the heat insulating support member 10. The cross-sectional area of the cross section perpendicular to the central axis A of the heat insulating support member 10 is set to an appropriate value from the perspectives of improving heat insulating properties and rigidity (strength). To improve the heat insulating properties of the heat insulating support member 10, the cross-sectional area is minimized, which reduces the cross-sectional area and rigidity. In this embodiment, the reinforcing sleeve 20 is provided to compensate for the reduced rigidity.
[0027] The heat insulating support member 10 includes a high-temperature side support end portion 11 located on the high-temperature portion P1 side, a low-temperature side support end portion 12 located on the low-temperature portion P2 side, and a support member main body portion 13 extending in the longitudinal direction L between the high-temperature side support end portion 11 and the low-temperature side support end portion 12. A hollow portion H penetrating the heat insulating support member 10 in the longitudinal direction L is formed inside the heat insulating support member 10. As shown in FIGS. 4 and 5 , the high-temperature side support end portion 11 and the low-temperature side support end portion 12 each have a cylindrical shape that is thinner than the support member main body portion 13. An end face 11a of the high-temperature side support end portion 11 abuts against the first connection end portion 3 and is joined to the first connection end portion 3 by, for example, adhesive bonding. An end face 12a of the low-temperature side support end portion 12 abuts against the second connection end portion 4 and is joined to the second connection end portion 4 by, for example, adhesive bonding.
[0028] 3, the reinforcing sleeve 20 is a cylindrical body that surrounds the heat-insulating support member 10 and extends in the longitudinal direction L. More specifically, the reinforcing sleeve 20 has a cylindrical shape with a fixed outer shape. The reinforcing sleeve 20 is made of metal, such as an aluminum alloy or stainless steel.
[0029] The reinforcing sleeve 20 includes a high-temperature end portion 21 located on the high-temperature portion P1 side, a low-temperature end portion 22 located on the low-temperature portion P2 side, and a reinforcing sleeve main body portion 23 extending in the longitudinal direction L between the high-temperature end portion 21 and the low-temperature end portion 22. As shown in Figures 4 and 5, the reinforcing sleeve main body portion 23 is tubular and thinner than the support member main body portion 13 of the heat-insulating support member 10. The high-temperature end portion 21 and the low-temperature end portion 22 are each tubular and thicker than the reinforcing sleeve main body portion 23 and the high-temperature support end portion 11 and the low-temperature support end portion 12, respectively.
[0030] As shown in FIG. 4 , the second connection end 4 includes a flange portion 4a facing the end face 12a of the low-temperature support end 12 and the low-temperature end face 22a of the low-temperature end 22; a connection piece 4b, which is a plate-like member protruding outward from the flange portion 4a in the longitudinal direction L; and a cylindrical protrusion 4d, for example, protruding inward from the flange portion 4a in the longitudinal direction L. The outer diameter of the flange portion 4a and the outer diameter of the low-temperature end 22 are substantially equal. A pinhole 4c is formed in the connection piece 4b. The protrusion 4d is fitted into the low-temperature end 22 of the reinforcing sleeve 20, positioning the low-temperature end 22. From another perspective, the inner peripheral surface 22b of the low-temperature end 22 abuts against the cylindrical peripheral surface (or stepped surface) 4e of the protrusion 4d. The end face 12a of the low-temperature support end 12 is coupled and fixed to the protrusion 4d of the second connection end 4. A constant cylindrical gap C extending in the longitudinal direction L around the central axis A is formed between the outer surface 13b of the support member main body 13 and the inner surface 23b of the reinforcing sleeve main body 23, and between the outer surface 12b of the low-temperature side support end 12 and the inner surface 22b of the low-temperature side end 22.
[0031] As shown in FIG. 5 , the first connecting end 3 includes a flange portion 3a facing the end face 11a of the high-temperature side support end 11 and the high-temperature side end face 21a of the high-temperature side end 21; a connecting piece 3b, which is a plate-like member protruding outward in the longitudinal direction L from the flange portion 3a; and a cylindrical protrusion 3d, for example, protruding inward in the longitudinal direction L from the flange portion 3a. The outer diameter of the flange portion 3a and the outer diameter of the high-temperature side end 21 are substantially equal. A pinhole 3c is formed in the connecting piece 3b. The protrusion 3d fits into the high-temperature side end 21 of the reinforcing sleeve 20, positioning the high-temperature side end 21. From another perspective, the inner peripheral surface 21b of the high-temperature side end 21 abuts against the cylindrical peripheral surface (or stepped surface) 3e of the protrusion 3d. The end face 11a of the high-temperature side support end 11 is joined and fixed to the protrusion 3d of the first connecting end 3. The gap C extending in the longitudinal direction L around the central axis A is formed between the outer peripheral surface 11b of the high-temperature side support end 11 and the inner peripheral surface 21b of the high-temperature side end 21.
[0032] As shown in FIG. 4 , the low-temperature side end 22 of the reinforcing sleeve 20 is connected to the second connecting end 4 by a plurality of fixing members 6, such as bolts. A plurality of through holes 4f are formed in the flange portion 4a of the second connecting end 4, through which the fixing members 6 are inserted, and a plurality of bolt holes 22f are formed in the low-temperature side end 22 of the reinforcing sleeve 20 at positions corresponding to the through holes 4f. An internal thread is formed in each of the bolt holes 22f. The fixing members 6 are screwed into the bolt holes 22f, thereby connecting the low-temperature side end 22 to the flange portion 4a of the second connecting end 4.
[0033] On the other hand, as shown in FIG. 5, the high temperature side end 21 of the reinforcing sleeve 20 is not connected to the first connection end 3.
[0034] The reinforcing sleeve 20 is made of a material having a linear expansion coefficient larger than that of the heat insulating support member 10. The linear expansion coefficient of the reinforcing sleeve 20 is, for example, 10 to 25 (10 -6 / K), and the linear expansion coefficient of the heat insulating support member 10 is in the range of 0 to 2 (10 -6 The difference between the linear expansion coefficient of the reinforcing sleeve 20 and the linear expansion coefficient of the heat insulating support member 10 is, for example, 8 to 25 (10 / K). -6 / K). The difference between the linear expansion coefficient of the reinforcing sleeve 20 and the linear expansion coefficient of the heat insulating support member 10 is about 8 (10 -6 / K) or more, but the difference in the linear expansion coefficient is greater than 0 and is 8 (10 -6 / K).
[0035] The length of the reinforcing sleeve 20 in the longitudinal direction L is adjusted so that there is no gap between the first connecting end 3 and the second connecting end 4 under room temperature conditions. As a result, under room temperature conditions, the high-temperature side end 21 (one end) of the reinforcing sleeve 20 contacts the first connecting end 3, and the low-temperature side end 22 (the other end) of the reinforcing sleeve 20 contacts the second connecting end 4. More specifically, the high-temperature side end surface 21a of the high-temperature side end 21 contacts the flange portion 3a (see FIG. 5), and the low-temperature side end surface 22a of the low-temperature side end 22 contacts the flange portion 4a (see FIG. 4). Such size adjustment can be achieved by, for example, a jointing process. Alternatively, size adjustment may be performed by inserting a shim between the second connecting end 4 and the reinforcing sleeve 20.
[0036] The high-temperature side end 21 is not joined to the first connection end 3, and due to the difference in linear expansion coefficients described above, the high-temperature side end 21 is configured to separate from the first connection end 3 in a predetermined low-temperature environment that is lower than room temperature. In other words, the low-temperature side end 22, which is a fixed end, cannot separate from the second connection end 4, but the high-temperature side end 21, which is a free end, can separate from the first connection end 3.
[0037] 6 and 7, the effects of the spacecraft support member 1 according to this embodiment as the ambient temperature (temperature environment) changes will be described. FIG. 6 is a cross-sectional view schematically illustrating the positional relationship among the components of the spacecraft support member 1 in a room-temperature environment. FIG. 7 is a cross-sectional view schematically illustrating the positional relationship among the components of the spacecraft support member 1 in a predetermined low-temperature environment. As shown in FIG. 6, in a room-temperature environment, the high-temperature end surface 21a of the high-temperature end portion 21 contacts the flange portion 3a, and the low-temperature end surface 22a of the low-temperature end portion 22 contacts the flange portion 4a. This state corresponds to the state before (or at) the launch of a satellite carrying the spacecraft structure S, for example. Assume that vibrations occur during launch, etc., and a compressive load is applied in the longitudinal direction L from the second connection end portion 4. In the spacecraft support member 1, the heat-insulating support member 10 and the reinforcing sleeve 20 exhibit resistance to (bear the load of) this compressive load. Therefore, buckling failure of the heat-insulating support member 10 is prevented.
[0038] The state shown in FIG. 7 corresponds to, for example, the state after launch of an artificial satellite carrying the spacecraft structure S. As shown in FIG. 7, in a predetermined low-temperature environment, due to the difference in linear expansion coefficients described above, the high-temperature end surface 21a of the high-temperature end portion 21 moves away from the flange portion 3a in the longitudinal direction L. A gap g is formed between the high-temperature end surface 21a and the first connecting end 3. As a result, heat conduction through the reinforcing sleeve 20 does not occur. Therefore, thermal control is achieved to maintain a predetermined temperature difference between the high-temperature portion P1 and the low-temperature portion P2. Regarding radial deformation based on the central axis A, the gap C (see FIGS. 4 and 5) is ensured as described above, so the reinforcing sleeve 20 does not come into radial contact with the heat-insulating support member 10. By appropriately setting the length and diameter of the reinforcing sleeve 20, the gap C remains even after thermal contraction (even if it is smaller than before thermal contraction), and the reinforcing sleeve 20 does not come into radial contact with the heat-insulating support member 10.
[0039] According to the spacecraft structure S of this embodiment, in a room-temperature environment where an external force such as a compressive load is expected to be applied, the high-temperature end 21 of the reinforcing sleeve 20 contacts the first connection end 3, and the low-temperature end 22 contacts the second connection end 4. In this state, the reinforcing sleeve 20 contributes to improving the support strength. The cooperation of the heat-insulating support member 10 and the reinforcing sleeve 20 ensures resistance to external forces. For example, in a conventional support member that does not include the reinforcing sleeve 20 (that is, is composed only of the heat-insulating support member 10), buckling or damage may occur in the heat-insulating support member 10 when a compressive load is applied. However, in the spacecraft structure S and the spacecraft support member 1 described above, buckling or damage to the heat-insulating support member 10 is prevented. Furthermore, because the linear expansion coefficient of the reinforcing sleeve 20 is greater than that of the heat-insulating support member 10, the reinforcing sleeve 20 contracts more than the heat-insulating support member 10 in a predetermined low-temperature environment that is lower than room temperature, such as outer space. The high-temperature end 21 is separated from the first connection end 3. As a result, the reinforcing sleeve 20 is thermally separated from the high-temperature portion P1 and the low-temperature portion P2, and does not form a heat transfer path. Therefore, the amount of heat entering the low-temperature portion P2 is the same as the amount of heat entering through only the heat insulating support member 10, and is not increased by providing the reinforcing sleeve 20.
[0040] In particular, the low-temperature side end 22 is connected to the second connection end 4, while the high-temperature side end 21 is not connected to the first connection end 3 and can be separated from the first connection end 3. As a result, in a predetermined low-temperature environment, the high-temperature side end 21 is separated from the first connection end 3. This effectively prevents heat from entering from the high-temperature part P1. In outer space, heat is transferred by conduction and radiation (convection does not occur in a vacuum environment). By separating the high-temperature side end 21 of the reinforcing sleeve 20 from the first connection end 3, heat transfer by conduction in particular is prevented. Note that the effect of thermal radiation is small under extremely low-temperature conditions.
[0041] The heat insulating support member 10 is a cylindrical body made of resin and extends in the longitudinal direction L. This reduces heat penetration into the low temperature part P2 through the heat insulating support member 10 while ensuring the strength required in space, etc.
[0042] The reinforcing sleeve 20 is a metallic cylindrical body that surrounds the heat insulating support member 10 and extends in the longitudinal direction L. The cylindrical structure makes it easy to reinforce the heat insulating support member 10 with a simple structure. Furthermore, because the reinforcing sleeve 20 is made of metal, it is easy to increase the difference between the linear expansion coefficient of the reinforcing sleeve 20 and the linear expansion coefficient of the heat insulating support member 10.
[0043] According to a configuration in which the first connection end 3 and the second connection end 4 are connected by a pin joint structure, even if the thermal contraction in the high temperature part P1 or the low temperature part P2 is large, three rotational components out of the six degrees of freedom become free, making it easy to release the thermal strain.
[0044] A support mechanism with a truss structure is preferable because it is less susceptible to lateral forces (directions perpendicular to the opposing direction of the high temperature portion P1 and the low temperature portion P2).
[0045] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, the low-temperature end 22 may not be coupled to the second connection end 4 and may be separable from the second connection end 4. If both the high-temperature end 21 and the low-temperature end 22 are separable from the first connection end 3 and the second connection end 4, both the high-temperature end 21 and the low-temperature end 22 are separated from the first connection end 3 and the second connection end 4. Even in this case, heat conduction does not occur through the reinforcing sleeve 20, and thermal control that maintains a predetermined temperature difference between the high-temperature portion P1 and the low-temperature portion P2 is achieved. In the present invention, it is sufficient that at least one of the high-temperature end 21 and the low-temperature end 22 is not coupled to the first connection end 3 and the second connection end 4 and is free.
[0046] Only one spacecraft support member 1 may be provided in the spacecraft structure S. One or more spacecraft support members 1 may be provided perpendicular to the high temperature part P1 or the low temperature part P2.
[0047] The material constituting the reinforcing member may be a metal other than aluminum alloy or stainless steel. Alternatively, the material constituting the reinforcing member may be a resin. For example, materials such as nylon or Vespel (registered trademark) may be used for the reinforcing member. Furthermore, in one spacecraft support member 1, multiple rod-shaped reinforcing members may be provided around (on the outer periphery of) one heat insulating support member 10.
[0048] The material constituting the heat insulating support member may be a resin other than FRP. The heat insulating support member 10 may be made of metal. The heat insulating support member 10 may be a solid columnar body instead of a cylindrical body.
[0049] The first connection end 3 and the second connection end 4 may be connected to the high temperature part P1 or the low temperature part P2, respectively, by a structure with play (movable range) in either direction, or may be connected to the high temperature part P1 or the low temperature part P2, respectively, by a rigid connection structure. [Explanation of symbols]
[0050] 1...spacecraft support member, 3...first connection end, 4...second connection end, 10...insulating support member, 20...reinforcing sleeve (reinforcing member), 21...high temperature side end (one end), 22...low temperature side end (other end), L...longitudinal direction, P1...high temperature portion, P2...low temperature portion, S...spacecraft structure.
Claims
1. A high temperature section; a low temperature section that is disposed apart from the high temperature section and that can be cooled to a temperature lower than that of the high temperature section; a first connection end connected to the high temperature portion; a second connection end connected to the low temperature portion; a heat insulating support member extending longitudinally between the first connection end and the second connection end; a reinforcing member provided on the outer circumferential side of the heat insulating support member, extending in the longitudinal direction, and having a high-temperature side end located on the high-temperature portion side that contacts the first connecting end and a low-temperature side end located on the low-temperature portion side that contacts the second connecting end under a normal temperature environment; The spacecraft structure, wherein the reinforcing member is made of a material having a linear expansion coefficient greater than that of the heat insulating support member.
2. 2. The spacecraft structure according to claim 1, wherein the low-temperature side end is coupled to the second connection end, and the high-temperature side end is not coupled to the first connection end and is separable from the first connection end.
3. 3. The spacecraft structure according to claim 1, wherein the heat insulating support member is a cylindrical body made of resin and extending in the longitudinal direction.
4. 3. The spacecraft structure according to claim 1, wherein the reinforcing member is a cylindrical body made of metal or resin that surrounds the heat insulating support member and extends in the longitudinal direction.
5. 3. The spacecraft structure according to claim 1, wherein the first connection end and the second connection end are connected to the high temperature portion and the low temperature portion, respectively, by a pin joint structure.
6. a first connection end portion and a second connection end portion provided at both ends in the longitudinal direction; a heat insulating support member extending in the longitudinal direction between the first connection end and the second connection end; a reinforcing member provided on an outer circumferential side of the heat insulating support member, extending in the longitudinal direction, and having one end in the longitudinal direction contacting the first connection end and the other end in the longitudinal direction contacting the second connection end under a room temperature environment; The support member for a spacecraft, wherein the reinforcing member is made of a material having a linear expansion coefficient greater than that of the heat insulating support member.
7. a first connection end portion and a second connection end portion provided at both ends in the longitudinal direction; a heat insulating support member extending in the longitudinal direction between the first connection end and the second connection end; a reinforcing member provided on an outer circumferential side of the heat insulating support member, extending in the longitudinal direction, and having one end in the longitudinal direction contacting the first connection end and the other end in the longitudinal direction contacting the second connection end under a room temperature environment; a support member for a spacecraft, wherein at least one of the one end or the other end of the reinforcing member is configured to be separated from at least one of the first connection end or the second connection end in a predetermined low-temperature environment that is lower than room temperature.
Citation Information
Patent Citations
Absorption type refrigerator
JP1998160314A