Deployable solar cell paddle

Abstract

This expandable solar cell paddle (1) is installed in a rocket in a stored state and expands in outer space. The expandable solar cell paddle (1) comprises a plurality of frame body units (10). Each of the frame body units (10) comprises a frame body (20) and a film (30). The frame body (20) has a frame shape. The film (30) is attached to the frame body (20). The film (30) appears as a mounting surface in an opening formed by the frame shape of the frame body (20), and a plurality of solar cells (40) are mounted to the mounting surface. The expandable solar cell paddle (1) has the effects of lowering costs, saving space, and offering excellent mass producibility compared to the rigid panel-type solar cell paddles widely used in the prior art.

Description

Technical Field

[0001] The present disclosure relates to a deployable solar cell paddle.

Background Art

[0002] For solar cell paddles, which are a power generation reduction for artificial satellites or space systems, various elements such as low cost, mass production, and storability are required. There are limitations with conventional rigid paddles in realizing these elements. Therefore, with the idea of mounting multiple satellites on rockets, which is directly related to cost, various companies are expanding the development and application of flexible types that achieve various high storabilities. Although there are various types of flexible paddle systems when subdivided, they are roughly classified into roll-out types and flat-pack types. Their respective features are as follows.

[0003] <Roll-out type> A flexible long sheet on which solar cells are mounted is wound around a mandrel of a winding mechanism mounted on a satellite structure for storage. The solar cell sheet is fed out and deployed by a flexible stem or mast composed of a carbon fiber sheet. The rigidity during deployment is ensured by the stem or mast. The deployment power is by the elastic energy of the stem or mast or an actuator mounted at the base. Due to the configuration of winding the sheet, the light-receiving surfaces of the cells do not face each other, so countermeasures against cell interference are easier than those of the flat-pack type. The roll-out type is suitable for large-scale applications such as covering the extra-large class (class with a generated power of 25 kW or more). As the scale increases, the proportion of the cost and mass of the deployment mechanism and support mechanism to the power scale becomes smaller, so there are advantages in terms of cost and mass. On the other hand, since a mandrel for winding the solar cell sheet is essential, this restricts the height and volume during storage, and the deployment mechanism becomes relatively complex, resulting in poor scalability.

[0004] <Flat-pack type> Flexible sheets or thin plates with solar cells mounted on them are arranged in strips and stored in a screen-like manner. There are those that are deployed by springs mounted on each deployment axis and those that are deployed by a stem or mast like a roll-out type. In order to increase the size, the rigidity during deployment becomes an issue. For this reason, almost all of the large flat-pack types that exist in the current world have a stem or mast. The flat-pack type does not require a mandrel for sheet winding, so the height and volume during storage can be reduced. If a configuration without a stem or mast is adopted, it is excellent in scalability, so it is excellent in cost and mass productivity. On the other hand, it is disadvantageous from the viewpoints of cost and mass for the extra-large class that the roll-out type can cover.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0006]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] Patent Document 1 is a published gazette regarding a large flat-pack type paddle. Patent Document 1 uses stem actuator extension for the large flat-pack type paddle. Patent Document 2 is a patent gazette regarding a stem-free small roll-out type paddle. Non-Patent Document 1 is a paper regarding a large roll-out type paddle. The large roll-out type paddle in this paper is of the type with stem self-extension.

[0008] As described above, a stem is required to make the paddle large (Patent Document 1, Non-Patent Document 1). Since the mechanism for extending the stem, whether it is an actuator or self-expansion, becomes complicated, there are problems in terms of scalability, mass productivity, and cost. Making it stemless is limited to small paddles because the rigidity during deployment cannot be ensured (Patent Document 2). When adopting a mandrel for winding, there are problems with the storage rate because the mandrel has restrictions on the height and volume during storage (Patent Document 1, Non-Patent Document 1).

[0009] The present disclosure aims to provide a flat-pack type solar cell paddle that does not require a stem and a mast, can be enlarged, has excellent storage performance, a simple configuration, and is suitable for mass production.

Means for Solving the Problems

[0010] The deployable solar cell paddle according to the present disclosure includes a plurality of frame units. Each of the plurality of frame units has a frame forming a frame shape, a film attached to the frame, appearing as a mounting surface in an opening formed in the frame shape formed by the frame, and having a plurality of solar cell cells mounted on the mounting surface, and includes.

Effects of the Invention

[0011] According to the present disclosure, it is possible to provide a flat-pack type solar cell paddle that does not require a stem and a mast, can be enlarged, has excellent storability, is simple in configuration, and is suitable for mass production.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Embodiments for Carrying Out the Invention

[0013] In the description of the embodiments and the drawings, the same elements and corresponding elements are denoted by the same reference numerals. The description of the elements denoted by the same reference numerals may be omitted or simplified as appropriate.

[0014] Embodiment 1. ***Description of the configuration*** The deployable solar cell paddle 1 of Embodiment 1 will be described with reference to FIGS. 1 to 14.

[0015] <1. Basic configuration> With reference to FIGS. 1 and 2, the basic configuration of the deployable solar cell paddle 1 will be described. FIG. 1 shows a perspective view of the deployable solar cell paddle 1 when deployed. FIG. 2 shows a state in which the deployable solar cell paddle 1 is folded. The deployable solar cell paddle 1 in FIG. 1 converts solar energy into electric power and supplies the converted electric power to a satellite or a space system.

[0016] The deployable solar cell paddle 1 includes a plurality of frame units 10. As shown in FIG. 1, each of the plurality of frame units 10 of the frame units 10 is arranged linearly when deployed. XYZ coordinates are shown in FIG. 1. In the drawings in which the coordinates are shown, the coordinates correspond. The deployable solar cell paddle 1 in FIG. 1 is composed of two rows, a first row 101 and a second row 102, in which a plurality of frame units 10 are directed in the linear direction 103. In the XYZ coordinates, when the deployable solar cell paddle 1 is deployed, the XY plane is the plane formed by a plurality of light-receiving surfaces described later as the XY plane, and the Y-axis direction is the linear direction 103. The Z-axis is one of the directions of the normal line of the XY plane. The first row 101 is composed of 23 frame units 10. The second row 102 is also composed of 23 frame units 10. The deployable solar cell paddle 1 is composed of two rows, the first row 101 and the second row 102, but the deployable solar cell paddle 1 may be composed of one row or three or more rows. Further, although an example in which the first row 101 and the second row 102 are composed of 23 frame units 10 is shown, the number of frame units 10 constituting the row is not limited.

[0017] When the two frame units 10 adjacent to each other during deployment in the linear direction 103 are referred to as one frame unit 10 and the other frame unit 10 respectively. In FIG. 1, an enlarged view of the region 501 of the deployable solar cell paddle 1 and an enlarged view of the region 502 are shown. The enlarged view of the region 501 shows the hinge connection between one frame unit 10 and the other frame unit 10. The enlarged view of the region 502 shows one frame unit 10 in which a plurality of solar cells 40 are arranged. As shown in the enlarged view of the region 501, in the first row 101, one frame unit 10 is connected to the other frame unit 10 adjacent to it during deployment by a hinge 50. The same applies to the second row 102.

[0018] As shown in FIG. 2, one frame unit 10 overlaps the other frame unit 10 so as to cover the other frame unit 10 by rotating around the hinge 50. The plurality of frame units 10 can be stored in layers when one frame unit 10 covers the other frame unit 10. In the deployable solar cell paddle 1, the positions of the hinges 50 are alternately located at the peaks of the mountains and the bottoms of the valleys of the plurality of frame units 10, and finally they are stacked in layers and folded. Here, the direction of the peak of the mountain is the Z-axis direction, and the direction of the valley of the mountain is the direction opposite to the Z-axis direction.

[0019] The frame unit 10 will be described. As shown in FIG. 1, each of the plurality of frame units 10 includes a frame 20 and a film 30.

[0020] <Frame 20> FIG. 3 is a schematic view showing the structure of the frame body 20. The frame body 20 has a frame shape. From the viewpoint of mass productivity, the frame body 20 is composed of beams having a simple cross-sectional shape. The beams can be made of metal or carbon fiber. The frame body 20 is formed, for example, in a polygonal shape by combining a plurality of beams by mechanical fastening or adhesion. The frame body 20 shown in FIG. 3 is formed in a square frame shape by a plurality of beams having an L-shaped cross section. Note that the L-shaped cross section is an example, and the cross-sectional shape is not limited. FIG. 3 shows cross sections A-A and B-B. In the frame body 20, the frame shape forms an opening 21.

[0021] <Film 30> FIG. 4 shows the film 30 attached to the frame body 20. In FIG. 4, the solar cell 40 is omitted. FIG. 4 shows cross sections C1-C1, C2-C2, and the film 30 in a developed state. The cross sections C1-C1 and C2-C2 correspond to the cross sections A-A and B-B in FIG. 3. The film 30 is formed of a polymer material. In FIG. 4, the film 30 is indicated by a broken line. In the following drawings, the film 30 may be indicated by a broken line. The film 30 is attached to the frame body 20. The film 30 appears as a mounting surface 31 in the opening 21 formed in the frame shape formed by the frame body 20. As shown in FIG. 1, a plurality of solar cells 40 are mounted on the mounting surface 31 of the film 30.

[0022] <Solar cell 40> A plurality of solar cells 40 are mounted on the mounting surface 31 of the film 30. As shown in FIG. 1, the plurality of solar cells 40 arranged on the film 30 of one frame unit 10 constitute an electric circuit 43. Each of the plurality of trapezoidal shapes shown in the frame unit 10 of FIG. 1 is a solar cell 40. The electric circuit 43 outputs the electric power generated by solar power generation from the output line 44. The output line 44 will be described later.

[0023] <Problems of the conventional rigid panel type> · Since the rigid panel has many manufacturing processes, it takes a long time and is costly. · The implementation of solar cells also needs to be done in panel units and is not suitable for mass production because continuous manufacturing is not possible. · There is a limit to reducing the thickness in order to ensure rigid strength. · For mounting on a satellite or a space system, in order to save space, it is necessary to reduce the panel size per sheet. Therefore, in the case of a rigid panel type solar cell paddle, the thickness of the rigid panel becomes a bottleneck. Due to the thickness of the rigid panel, when trying to secure the light receiving area, the storage height in the stacking direction of the panels becomes too high when folding and storing in a screen shape.

[0024] <Effects according to the basic configuration> · By adopting the above configuration, compared with the conventionally widely used rigid panel type, properties such as low cost, space saving, and excellent mass productivity can be obtained. · In the configuration of the deployable solar cell paddle 1, the frame body 20 can be configured by mechanically fastening metal or carbon fiber beams having a simple cross-sectional shape with mass productivity. Therefore, it is easy to ensure the rigidity of the beams, and the thickness of the frame unit 10 corresponding to one panel can be reduced. That is, the thickness of the frame body 20 can be reduced. · In the deployable solar cell paddle 1, a plurality of solar cells 40 are mounted on the film 30. With this configuration, production can be continuously carried out compared with the rigid panel type in which productivity was segmented for each panel. Therefore, low cost and mass productivity can be ensured.

[0025] <2. Spacing between light receiving surfaces> Figure 5 shows the state when the deployable solar cell paddle 1 is stored. Figure 6 shows the D-D cross section of Figure 5. Referring to the lowermost frame unit 10 in Fig. 6, the mounting surface 31 of the film 30 is located below the frame 20 in the downward direction 34, which is the direction from the mounting surface 31 to the back surface 32 of the mounting surface 31. The back surface of the light-receiving surface 41 of each of the plurality of solar cells 40 is attached to the mounting surface 31. As shown in Fig. 6, taking one of the second frame units 10 from the top and the other of the third frame units 10 from the top as an example, during storage, the entire light-receiving surfaces 42 formed by the light-receiving surfaces 41 of the respective solar cells 40 face each other. With this configuration, a plurality of solar cells 40 can be arranged on the side in the downward direction 34, like the lowermost frame unit 10 in Fig. 6. Therefore, during storage in Fig. 6, the entire light-receiving surfaces 42 face each other, and there are the following effects. Since the direction from the mounting surface 31 to the back surface 32 of the mounting surface 31 is the downward direction 34, in the frame units 10 such as the second and fourth from the top in Fig. 6, it is opposite to the lowermost frame unit 10 in Fig. 6, the downward direction 34, and the opposite direction described later.

[0026] <Effect of ensuring the interval between light-receiving surfaces> The light-receiving surface 41 of the solar cell 40 is covered with cover glass to prevent radiation degradation in the space environment. For this reason, the cover glass covering the light-receiving surface 41 has a high risk of mechanical damage due to contact with other components in the vibration environment during rocket launch. However, since the mounting surface 31 of the film 30 is located below the frame 20 in the downward direction 34, which is the direction from the mounting surface 31 to the back surface 32 of the mounting surface 31, the interval between the opposing entire light-receiving surfaces 42 can be made relatively large. Therefore, even without components or materials that directly protect the light-receiving surface, by ensuring the spatial distance between the entire light-receiving surfaces 42, contact between the entire light-receiving surfaces 42 and damage to the entire light-receiving surfaces 42 can be prevented. Therefore, there are advantages in terms of cost and mass productivity.

[0027] Also, in FIG. 6, when the deployable solar cell paddle 1 is stored, the light-receiving surface interval 45 between the entire light-receiving surfaces 42 is set to be at least twice the thickness of the frame body 20. Here, the thickness of the frame body 20, as explained with respect to the lowermost frame unit 10 in FIG. 6, is the maximum width 36 in the downward direction 34 and the direction 35 opposite to the downward direction 34. As shown in FIG. 6, the opposite surfaces of the light-receiving surfaces 41 of the solar cells 40 can be placed back-to-back via their respective films 30, and the interval between the entire light-receiving surfaces 42 can be ensured to be at least twice the thickness of the frame body 20. Thereby, when the deployable solar cell paddle 1 is stored, the interval between the adjacent frame units 10 and between the entire light-receiving surfaces 42 of the frame units 10 can be maintained. Therefore, also from this point, there is the same effect as the above-described configuration of "the mounting surface 31 of the film 30 is located below the frame body 20 in the downward direction 34."

[0028] <3. Thermal deformation absorption structure 60 of film to frame body> Referring to FIGS. 7 and 8, a thermal deformation absorption structure 60 for attaching the film 30 to the frame body 20 will be described. FIG. 7 shows the frame unit 10 with the solar cells 40 omitted. FIG. 8 shows three types in the E-E cross-section including the thermal deformation absorption structure 60. As shown in FIG. 7, the deployable solar cell paddle 1 includes a thermal deformation absorption structure 60 that allows the thermal deformation of the film 30 with respect to the frame body 20 to escape as a mounting structure between the film 30 and the frame body 20. The thermal deformation absorption structure 60 is a structure for attaching the film 30 to the frame body 20 with respect to the entire circumferential portion of the frame body 20. In FIG. 8, it shows that any one of the three types from type 1 to type 3 is used in the E-E cross-section. The E-E cross-section is a cross-section adopted for explanation, and the three types from type 1 to type 3 are arranged in plurality over the entire circumference of the frame body 20. The thermal deformation absorption structure 60 includes a surface fastener structure 61 of type 1. The surface fastener structure 61 attaches the film 30 to the frame body 20 by attaching a film surface fastener 70b, which is a surface fastener attached to the film 30, to a frame body surface fastener 70a, which is a surface fastener attached to the frame body 20.

[0029] Type 1 in Fig. 8 shows the hook-and-loop fastener structure 61. In the thermal deformation absorption structure 60, the hook-and-loop fastener structure 61 is mainly used, and the mechanical fastening methods shown in Fig. 8 are used as auxiliary attachments for Types 2 and 3. Both Types 2 and 3 may be used in combination, or either one of them may be used in combination. Types 2 and 3 have a structure in which the shaft portion 23 of the shaft body 22 attached to the frame body 20 having the shaft portion 23 penetrates through the through hole 33 formed in the film 30. Type 2 has a structure in which the shaft portion 23 of the pin 26, which is the shaft body 22 attached to the frame body 20 having the shaft portion 23, penetrates through the through hole 33 formed in the film 30. Type 3 is a configuration using a set of screw 27 and nut 28, or a rivet. In Type 3 of Fig. 8, a set of screw 27 and nut 28 is shown. When a set of screw 27 and nut 28 is adopted as Type 3, as shown in Fig. 8, it has a structure in which the shaft portion 23 of the screw 27, which is the shaft body 22 attached to the frame body 20 having the shaft portion 23, penetrates through the through hole 33 formed in the film 30. The screw 27 is attached to the frame body 20 with the nut 28. When a rivet is adopted as Type 3, similar to the screw 27, it has a structure in which the shaft portion of the rivet, which is the shaft body attached to the frame body having the shaft portion, penetrates through the through hole 33 formed in the film 30. As the mechanical fastening of Type 3, a set of screw 27 and nut 28 may be adopted, a rivet may be adopted, or both a set of screw 27 and nut 28 and a rivet may be adopted. Type 2 is a loose attachment in which the film 30 is movable with respect to the axial direction 29 in which the shaft portion 23 extends. In contrast, Type 3 is a tight attachment in which the film 30 does not move with respect to the axial direction 29.

[0030] <Effect of the thermal deformation absorption structure 60> As described above, the method for attaching the film 30 to the frame body 20 is the thermal deformation absorption structure 60. The thermal deformation absorption structure 60 mainly uses the surface fastener structure 61 shown as type 1, and supplements it with mechanical fastening using the pin 26 shown as type 2, the screw 27 and nut combination shown as type 3, rivets, etc. Any of the combinations of type 1 and type 2, type 1 and type 3, and type 1, type 2, and type 3 may be used. The type 1 surface fastener structure 61, which is the main fixing method, has flexibility in attaching the frame body 20 and the film 30. The surface fastener structure 61 can release the thermal deformation of the film 30 relative to the frame body 20 caused by the difference in linear expansion of the components under the thermal cycle environment in space. Although mechanical fastening such as type 2 and type 3 is used in combination, it is configured to allow the film 30 to move relative to the frame body 20 with respect to thermal deformation. With the above configuration, it is possible to eliminate the tension adjustment mechanism that was essential for the conventional flexible type. Therefore, since the configuration of the frame unit 10 is a simple configuration, cost reduction and mass productivity can be ensured.

[0031] <4. Fixing of the film 30 by the protrusion 24> Referring to FIG. 9, a configuration in which the film 30 is sandwiched and fixed by the protrusion 24 provided on the frame body 20 when the deployable solar cell paddle 1 is stored will be described. FIG. 9 shows a D-D cross section of FIG. 5.

[0032] As shown in FIG. 9, the frame body 20 has a protrusion 24. The protrusion 24 of the frame body 20 of one frame unit 10, together with the protrusion 24 of the frame body 20 of the other frame unit 10, sandwiches and fixes the film 30 of one frame unit 10 and the film 30 of the other frame unit 10 in a state where a plurality of frame units 10 are stored in layers.

[0033] This will be described in detail below. In Fig. 9, the frame units 10 are denoted as frame units #1, #2, #3, and #4 in order from the top. Each frame 20 of the frame units #1, #2, #3, and #4 is denoted as frame #1, #2, #3, and #4. Pay attention to frame #2 and frame #3, and frame #3 and frame #4. Between frame #2 and frame #3, the entire light-receiving surfaces 42 face each other. In region 503, frame #2 has a protrusion 24 at the end in the stacking direction, and frame #3 has a protrusion 24 at the end in the stacking direction on the side facing frame #2. The film 30 of frame unit #2 and the film 30 of frame unit #3 are sandwiched and fixed by the protrusion 24 of frame #2 and the protrusion 24 of frame #3. Between frame #3 and frame #4, the films on which the back surfaces of the entire light-receiving surfaces 42 are arranged face each other. In region 504, the protrusion 24 of frame #3 is arranged between frame #3 and the film 30, and the protrusion 24 of frame #4 is arranged between frame #4 and the film 30. The film 30 of frame unit #3 and the film 30 of frame unit #4 are sandwiched and fixed by the protrusion 24 of frame #3 and the protrusion 24 of frame #4.

[0034] <Effect of fixing film 30 by protrusion 24> When the deployable solar cell paddle 1 is deployed, as described in Fig. 8, in order to release the thermal deformation due to the thermal cycle, the frame and the film are configured to be loosely fixed. Further, when the deployable solar cell paddle 1 is stored, that is, when launched by a rocket, since the frame 20 has the protrusion 24, the film is rigidly fixed to the frame 20 which is a structure. For this reason, the film 30 can withstand the launch vibration environment. Therefore, for the film 30, a simple configuration that can withstand the vibration during launch and a simple configuration that can withstand the thermal cycle during deployment described in Fig. 8 can be realized.

[0035] <5. Mechanical contact> Fig. 10 shows the mechanical contact 25. One frame unit 10 and the other frame unit 10 are provided with a mechanical contact 25 that transmits loads to each other during deployment.

[0036] This will be described in detail below. As shown in FIG. 10, mechanical contacts 25 for transmitting loads to each other are provided between adjacent frame bodies 20 when deployed. FIG. 10 shows four frame units 10 in the region 505 of FIG. 1. The solar cell 40 is omitted in FIG. 10. The mechanical contact 25 is composed of a member 25A disposed on one frame body 20 and a member 25B disposed on the other frame body 20. The mechanical contact 25 maintains the deployed shape of the deployable solar cell paddle 1 only by the rigidity of the frame body 20. Also, the hinge 50 and the mechanical contact 25 are configured to be able to receive moment loads by ensuring a spatial distance in the X-Y plane view.

[0037] <Effect of mechanical contact> Conventional flexible paddles are not composed of rigid materials in which each unit has sufficient rigidity to constitute the entire paddle alone. For example, each unit is composed of a single film or a thin plate. Therefore, in order to ensure rigidity during deployment, a support structure such as a mast or a stem is essential. Regarding the support structure, there are demerits such as poor design scalability, unsuitability for mass production, complexity of the support structure and its deployment mechanism, high cost, and space occupation. However, with the configuration of providing the mechanical contact 25, the support structure and its deployment mechanism become unnecessary. Essentially, each frame body 20 bears the rigidity, and by creating a load path between the frame body 20 and the frame body 20 by the mechanical contact 25, the rigidity of the entire deployable solar cell paddle 1 is ensured. Therefore, a deployable solar cell paddle 1 with low cost, space saving, and excellent mass productivity can be realized.

[0038] <6. Wiring arrangement during deployment> FIG. 11 shows an output line 44 for extracting power from the frame unit 10. A plurality of solar cells 40 constitute an electric circuit 43. The frame unit 10 includes an output line 44 connected to the electric circuit 43. The output lines 44 of each frame unit 10 are arranged along the side surfaces of the plurality of frame units 10 in the same direction 506, which is one direction in a straight line, when the plurality of frame units 10 are deployed.

[0039] The following will be described in detail. As shown in FIG. 11, an output line 44 connected to an electric circuit 43 formed by a plurality of solar cells 40 is led out from a side of the frame body 20 and is made to crawl on the side surface of the frame body 20. The output line 44 led out from the frame body 20 is routed toward the base of the deployable solar cell paddle 1, that is, in the same direction 506, without passing through a connector or a terminal. The three frame units 10 in FIG. 11 are denoted as frame unit #1, #2, and #3 from the left. The output lines 44 of the frame units #1, #2, and #3 are denoted as output line #1, #2, and #3, respectively. Along the side surface of the frame unit #1, output line #1 runs; along the side surface of the frame unit #2, output lines #1 and #2 run; and along the side surface of the frame unit #3, output lines #1, #2, and #3 run. Finally, along the side surface of the frame unit #N, output lines #1, #2, #3, ···, #N run. That is, in a flat pack in which the thickness of the frame body 20 is made thin by stacking the output lines in the thickness direction, it becomes impossible to mount them. Therefore, in the deployable solar cell paddle 1, the bundle of output lines is laid flat, and the width of the bundle of output lines increases as it goes toward the base. A plurality of output lines 44 going in the same direction 506 reach a satellite or a space system.

[0040] <Effect of Output Line Arrangement> Conventionally, a configuration for transmitting power to a satellite or a space system has been a configuration in which connectors mounted on each panel are connected. Therefore, as the size of the solar cell paddle increases according to the required power, the number of components increases, and wiring design is required each time according to the size. On the other hand, according to the configuration of the output line 44 shown in FIG. 11, wire splicing between the frame units 10 is unnecessary, and connectors are unnecessary for each frame unit 10. Therefore, the number of components can be reduced, the reliability of performance can be ensured, and cost reduction can be achieved. Further, by adopting a configuration in which the output line 44 is directly led out from each frame unit toward a satellite or a space system, circuit design and wiring design according to the required power of the solar cell paddle become unnecessary. That is, in the deployable solar cell paddle 1, by adjusting the number of frame units 10 according to the required power, the deployable solar cell paddle 1 corresponding to the required power can be flexibly designed. Therefore, according to the deployable solar cell paddle 1, a configuration that is designed to be scalable with respect to the required power can be achieved, and the construction period and cost can be reduced.

[0041] <7. Elastic body 80> FIG. 12 shows an elastic body 80 that is arranged independently of the hinge 50 constituting the rotation axis and generates the deployment power of the deployable solar cell paddle 1. The deployable solar cell paddle 1 includes an elastic body 80 that stores elastic energy when deploying one frame unit 10 with respect to the other frame unit 10, between the one frame unit 10 and the other frame unit 10. In FIG. 12, a coil spring is shown as an example of the elastic body 80. The elastic body 80 stores elastic energy that causes a deployment operation from the stored state to the deployed state when it becomes the stored state shown in FIG. 2 from the deployed state.

[0042] <Effect of having the elastic body 80> Due to the elastic body 80, the configuration of the deployment mechanism realized by the hinge 50 and the elastic body 80 becomes simple. Therefore, cost reduction can be achieved. In addition, since the deployment mechanism can be realized with a simple configuration of the combination of the hinge 50 and the elastic body 80, the mass productivity of the deployable solar cell paddle 1 can be ensured. Also, design was required each time depending on the size of the solar cell paddle. In this regard, in the deployable solar cell paddle 1, by adjusting the number of elastic bodies 80 arranged between the one frame unit 10 and the other frame unit 10, it is possible to cope with the sizing of the deployment torque. As a result, a configuration that is scalable with respect to the solar cell paddle size can be achieved. Therefore, unlike the conventional solar cell paddle unit, design is not required each time, and the construction period and cost can be reduced.

[0043] <8. Deployment delay mechanism 90> FIGS. 13 and 14 are diagrams for explaining the deployment delay mechanism 90. FIG. 13 shows the F-F cross-section where the deployment delay mechanism 90 appears. FIG. 14 shows the deployment by the deployment delay mechanism 90.

[0044] As shown in FIG. 14, the deployable solar cell paddle 1 includes a deployment delay mechanism 90 that sequentially starts a deployment operation from the start frame unit 10, which is the frame unit #1 located at one end of the layer in the stored state, toward the end frame unit #E located at the other end of the layer in the stored state, with respect to the end frame unit #E. The delayed deployment operation by the deployment delay mechanism 90 will be described with reference to FIG. 14.

[0045] The deployment delay mechanism 90 is realized by a plurality of hinges 50, a plurality of elastic bodies 80, a plurality of cams, and a plurality of rollers. The frame unit 10 is denoted as the frame unit #1. In FIG. 14, a plurality of frame units 10 from the frame unit #1 to the frame unit #E are folded in layers. The plurality of frame units 10 from the frame unit #1 to the frame unit #E are folded in layers in the stacking direction 507. (1) In state 1, the frame unit #1 tries to rotate around the hinge 50 by the elastic body 80 disposed between the frame unit #1 and the frame unit #2. However, since the frame unit #1 is pressed by the pressing force 508 in the stacking direction 507, the frame unit #1 does not open. In this state, the frame units after the frame unit #2 do not open. (2) The pressing force 508 is removed. The frame unit #1 begins to open by the elastic force of the elastic body 80. The frame unit #2 tries to open by the elastic force of the elastic body 80 on the opposite side. However, the cam 201 and the roller 301 are engaged, and the cam 202 and the roller 302 are also engaged. When the frame unit #2 presses the frame unit #1, the cam 201 and the roller 301 receive this force, so the frame unit #1 does not move upward. The frame unit #1 continues to rotate. (3) In state 2, due to the rotation of the frame unit #1, the engagement between the cam 201 and the roller 301 is released, and the cam 201 and the roller 301 cannot receive the force exerted by the frame unit #2 pushing the frame unit #1. Therefore, the frame unit #2 starts to rotate by the elastic force of the elastic body 80 on the opposite side. The state changes from state 2 to state 3. In FIG. 14, the left-side deployment delay mechanism 90 in the folded state in layers is shown, but the same deployment delay mechanism 90 is also arranged on the right side. For this reason, the frame unit #1 opens, then the frame unit #2 opens, then the frame unit #3 opens, and so on, and the frame units 10 are sequentially deployed.

[0046] <Effect of the deployment delay mechanism 90> As shown in FIG. 14, the deployable solar cell paddle 1 has a deployment delay mechanism 90. The deployment delay mechanism 90 is realized by the entire plurality of hinges 50, the plurality of elastic bodies 80, the plurality of cams, and the plurality of rollers. In conventional solar cell paddles, it is common to be equipped with a synchronization mechanism to synchronize the overall movement. For this reason, adjustment during assembly is necessary, and design is required each time the size of the solar cell paddle changes. According to the deployment delay mechanism 90, design and adjustment after assembly are no longer necessary. Therefore, a scalable configuration can be achieved with respect to the paddle size, and the construction period and cost can be reduced.

Explanation of reference numerals

[0047] 1 Deployable solar cell paddle, 10 Frame unit, 20 Frame, 21 Opening, 22 Shaft body, 23 Shaft portion, 24 Protrusion, 25 Mechanical contact, 26 Pin, 27 Screw, 28 Nut, 29 Axial direction, 30 Film, 31 Mounting surface, 32 Back surface, 33 Through hole, 34 Downward direction, 35 Opposite direction, 40 Solar cell, 41 Light receiving surface, 42 Total light receiving surface, 43 Electric circuit, 44 Output line, 45 Light receiving surface interval, 50 Hinge, 60 Thermal deformation absorption structure, 61 Surface fastener structure, 70a Frame surface fastener, 70b Film surface fastener, 80 Elastic body, 90 Deployment delay mechanism, 101 First row, 102 Second row, 103 Linear direction, 201, 202 Cam, 301, 302 Roller, 501, 502, 503, 504, 505 Region, 506 Same direction, 507 Laminating direction, 508 Pressing force.

Claims

1. In a deployable solar cell paddle, comprising a plurality of frame units, each frame unit of the plurality of frame units has a frame shape forming an opening, and has a rigidity to maintain the frame shape from the storage time to the deployment time of the deployable solar cell paddle, a film attached to the frame body, appearing as a mounting surface in the opening formed in the frame shape formed by the frame body, and having a plurality of solar cell cells mounted on the mounting surface, A deployable solar cell paddle comprising:

2. Each frame unit of the plurality of frame units is arranged linearly when deployed, one of the two adjacent frame units of the plurality of frame units when deployed is connected to the other adjacent frame unit by a hinge when deployed, the one frame unit overlaps the other frame unit so as to cover the other frame unit by rotating around the hinge, the plurality of frame units The deployable solar cell paddle according to claim 1, wherein the one frame unit can be stored in layers by covering the other frame unit.

3. The mounting surface of the film is located below the frame body in the downward direction, which is the direction from the mounting surface to the back surface of the mounting surface, each solar cell of the plurality of solar cells has the back surface of the light receiving surface attached to the mounting surface, the one frame unit and the other frame unit When stored, the entire light receiving surfaces formed by the light receiving surfaces of each solar cell of the plurality of solar cells face each other. The deployable solar cell paddle according to claim 2.

4. The deployable solar cell paddle as a mounting structure between the film and the frame body, comprises a thermal deformation absorption structure that allows thermal deformation of the film with respect to the frame body to escape. The deployable solar cell paddle according to claim 2 or claim 3.

5. The thermal deformation absorption structure includes a surface fastener structure for attaching the film to the frame body by attaching a film surface fastener, which is a surface fastener attached to the film, to a frame body surface fastener, which is a surface fastener attached to the frame body. The deployable solar cell paddle according to claim 4.

6. The frame body has protrusions, the protrusions of the frame body of the one frame unit The deployable solar cell paddle according to any one of claims 2 to 5, wherein the film of the one frame unit and the film of the other frame unit are sandwiched and fixed in a state where the plurality of frame units are stored in layers together with the protrusions of the frames of the other frame unit.

7. The one frame unit and the other frame unit The deployable solar cell paddle according to any one of claims 2 to 6, which comprises mechanical contacts that transmit loads to each other during deployment.

8. The plurality of solar cell panels constitute an electrical circuit, The frame unit further comprises output lines connected to the electrical circuit, The output lines of each of the plurality of frame units of the plurality of frame units The deployable solar cell paddle according to any one of claims 2 to 7, which are arranged along the side surfaces of the plurality of frame units in the same direction, which is one direction in the linear shape, when the plurality of frame units are deployed.

9. The deployable solar cell paddle further comprises an elastic body that stores elastic energy for deploying the one frame unit with respect to the other frame unit during storage, between the one frame unit and the other frame unit. The deployable solar cell paddle according to any one of claims 2 to 8.

10. The deployable solar cell paddle further comprises a deployment delay mechanism that sequentially starts a deployment operation from a start frame unit, which is a frame unit located at one end of the plurality of frame units in the layered state during storage, to an end frame unit, which is a frame unit located at the other end of the plurality of frame units in the layered state during storage. The deployable solar cell paddle according to any one of claims 2 to 9.

11. The frame The deployable solar cell paddle according to any one of claims 1 to 10, wherein the frame shape is formed by a plurality of beams by repeating a structure in which an end of one beam is fastened to an end of another beam.

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