Folding and unfolding device and spacecraft

Abstract

The invention belongs to the technical field of aerospace equipment, and discloses a folding and unfolding device and a spacecraft, the folding and unfolding device comprises a bottom plate, a reel, an unfolding arm and a locking and releasing mechanism, the unfolding arm is made of an elastic material, one end of the unfolding arm is connected with the bottom plate, the other end of the unfolding arm is connected with the reel, and the unfolding arm can be rolled along with a flexible solar cell array; elastic potential energy is stored; and the locking and releasing mechanism is configured to lock the reel on the bottom plate after the flexible solar cell array is wound, and can switch the reel from a locking state to a releasing state, so that the unfolding arm can release the elastic potential energy, and the unfolding arm and the flexible solar cell array are synchronously unfolded. Compared with a traditional folding and unfolding device, complex components such as a motor, a gear transmission system and a control circuit are omitted. Therefore, the unfolding structure is greatly simplified, the manufacturing cost is reduced, the weight of the folding and unfolding device and the space occupied area are obviously reduced, and the space requirement of a small spacecraft is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aerospace equipment, and in particular to a folding and unfolding device and a spacecraft. BACKGROUND

[0002] During long-term operation in orbit, a spacecraft mainly relies on a solar wing to provide electric energy for the spacecraft. When the spacecraft is launched, the solar wing is in a folded state to reduce the occupied volume. Specifically, the solar wing includes a folding and unfolding device and a flexible solar cell array, and the flexible solar cell array can be folded under the action of the folding and unfolding device to facilitate the spacecraft entering space. After the spacecraft enters orbit, the folding and unfolding device can unfold the flexible solar cell array to facilitate power generation.

[0003] To ensure the stability of the flexible solar cell array during unfolding, the folding and unfolding device is often provided with complex components such as motors, gear transmission systems, and control circuits, resulting in a complex overall structure and large volume of the solar wing, which cannot meet the space requirements of small spacecraft.

[0004] Therefore, the above problems need to be solved. SUMMARY

[0005] The present application aims to provide a folding and unfolding device to reduce the overall volume of the solar wing and meet the space requirements of small spacecraft.

[0006] To achieve this goal, the present application adopts the following technical solutions:

[0007] The folding and unfolding device is used for folding and unfolding a flexible solar cell array, and includes:

[0008] a bottom plate fixed to one end of the flexible solar cell array;

[0009] a spool fixed to the other end of the flexible solar cell array and configured to wind the flexible solar cell array on the bottom plate;

[0010] an unfolding arm made of a thin-walled elastic composite material, one end of the unfolding arm being connected to the bottom plate, the unfolding arm being configured to be flattened along its cross-sectional direction in a winding state and wound on the spool to store elastic potential energy, and to drive the flexible solar cell array to unfold by using the elastic potential energy after being released;

[0011] a locking and releasing mechanism configured to lock the spool and the unfolding arm to the bottom plate after the flexible solar cell array is wound up, and to switch the spool and the unfolding arm from the locked state to the released state.

[0012] As preferred, the deployment arm is further configured to have its cross section restored to a non-planar tubular or channel structure in the released state to form a rigid arm to provide longitudinal support force along the deployment direction for the deployed flexible solar cell array.

[0013] As preferred, a connecting mechanism is provided between the deployment arm and the reel, the connecting mechanism comprising:

[0014] a connecting box having a box opening;

[0015] a rotating shaft rotatably arranged inside the connecting box, and one end of the rotating shaft is capable of penetrating through the connecting box and fixedly connected with the reel;

[0016] a guiding portion arranged inside the connecting box and configured to guide the deployment arm to orientally pass out of the box opening to limit the interlaminar relative shear motion of the deployment arm during the releasing process.

[0017] As preferred, the locking and releasing mechanism comprises a locking and releasing assembly arranged on the bottom plate and configured to lock the connecting mechanism.

[0018] As preferred, the locking and releasing assembly comprises a fuse wire roll and a locking block, and the free end of the fuse wire roll is capable of connecting with the locking block after bypassing the connecting mechanism;

[0019] the fuse wire roll is connected with an external power supply, and the power supply is configured to electrify the two fuse wire rolls to fuse the fuse wire of the fuse wire roll.

[0020] As preferred, two deployment arms are provided and distributed on both sides of the flexible solar cell array.

[0021] As preferred, the flexible solar cell array comprises a substrate and cell pieces uniformly distributed on the substrate.

[0022] the reel is flat, and when the substrate is wound on the reel, the cell pieces can be stacked on the planar section of the reel.

[0023] As preferred, the flexible solar cell array further comprises a polyimide foam arranged on the back of the substrate.

[0024] As preferred, the bottom plate comprises an aluminum panel, a honeycomb core and an aluminum back plate arranged in layers.

[0025] the aluminum panel and the honeycomb core and the honeycomb core and the aluminum back plate are connected by an adhesive.

[0026] A spacecraft comprising a driving member and two folding and unfolding devices as described above connected to the driving member, the two folding and unfolding devices are symmetrically arranged about the driving member, and the driving member is configured to drive the two folding and unfolding devices to rotate.

[0027] The two folding and unfolding devices are both fixed with a flexible solar cell array.

[0028] The spacecraft has the advantages that:

[0029] The folding and unfolding device and the spacecraft have the advantages that: BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a structural schematic view of the reel of the folding and unfolding device in the locking state of the present application;

[0031] Figure 2 is a structural schematic view of the reel of the folding and unfolding device in the releasing state of the present application

[0032] Figure 3 is Figure 2 is a local enlarged view of A in the present application;

[0033] Figure 4 is a structural schematic view of the connecting mechanism in the present application;

[0034] Figure 5 is a structural schematic view of the spacecraft in the present application;

[0035] Figure 6 is a structural schematic view of the spacecraft in the present application.

[0036] In the drawings:

[0037] 100, driving member; 200, folding and unfolding device; 300, flexible solar cell array;

[0038] 1, bottom plate; 2, reel; 21, flat section; 22, arc section; 3, deployment arm; 41, lock release assembly;

[0039] 5, connecting mechanism; 51, connecting box; 511, box opening; 52, rotating shaft; 53, guide portion; 531, connecting shaft; 532, roller. DETAILED DESCRIPTION

[0040] The application will be further described below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are intended to be merely illustrative of the application and not in limitation thereof. It should also be understood that, for the purpose of clarity, only those structures of the application that are relevant to the present application have been shown in the drawings.

[0041] In the description of the present application, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0042] In the present application, unless otherwise explicitly specified and limited, the first feature "on" or "under" the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "above" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0043] In the description of the present embodiment, the terms "up", "down", "left", "right" and the like orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0044] Please refer to Figures 1 to 4In the embodiment, a folding and unfolding device 200 for folding and unfolding a flexible solar cell array 300 is provided, which comprises a bottom plate 1, a winding shaft 2, an unfolding arm 3 and a locking and releasing mechanism. The bottom plate 1 is fixed to one end of the flexible solar cell array 300. The winding shaft 2 is fixed to the other end of the flexible solar cell array 300 and is configured to wind the flexible solar cell array 300 on the bottom plate 1. The unfolding arm 3 is a thin-walled elastic composite material member. One end of the unfolding arm 3 is connected to the bottom plate 1. The unfolding arm 3 is configured to be flattened along its cross-sectional direction in the winding state and wound on the winding shaft 2 to store elastic potential energy, and to drive the flexible solar cell array 300 to unfold by using the elastic potential energy after being released. The locking and releasing mechanism is configured to lock the winding shaft 2 and the unfolding arm 3 to the bottom plate 1 after the winding of the flexible solar cell array 300 is completed, and to switch the winding shaft 2 and the unfolding arm 3 from the locked state to the released state, so that the unfolding arm 3 can release the elastic potential energy, thereby enabling the unfolding arm 3 to unfold synchronously with the flexible solar cell array 300.

[0045] It can be understood that the flexible solar cell array 300 is fixed between the bottom plate 1 and the winding shaft 2. By rotating the winding shaft 2, the flexible solar cell array 300 can be wound together with the unfolding arm 3 on the bottom plate 1. Then, the winding shaft 2 is locked by the locking and releasing mechanism, and the winding shaft 2 can be released after the spacecraft enters the orbit, so that the unfolding arm 3 drives the winding shaft 2 to move away from the bottom plate 1. During the movement of the winding shaft 2, the flexible solar cell array 300 can be unfolded, that is, the unfolding arm 3 can be unfolded synchronously with the flexible solar cell array 300, thereby avoiding the situation that the flexible solar cell array 300 is pulled, wrinkled or damaged due to asynchronous unfolding. The elastic unfolding process is smooth and has small impact. Compared with the traditional folding and unfolding device 200, the complex motor, gear transmission system, control circuit and other components are omitted. This not only greatly simplifies the unfolding structure and reduces the manufacturing cost, but also significantly reduces the weight and space occupation area of the folding and unfolding device 200, thereby meeting the space requirements of small spacecraft.

[0046] In addition, the deployable arm 3 is configured such that, in the released state, its cross-section returns to a non-planar tubular or trough-shaped structure to form a rigid arm, thereby providing longitudinal support force along the deployment direction for the deployed flexible solar cell array 300. Understandably, during winding, the unfolding arm 3 is forced to elastically buckle along its width, flattening its central cross-section and storing elastic potential energy. Upon release, the elastic buckling is released, and the unfolding arm 3 returns to its center alignment state using the released elastic potential energy, forming a tubular or groove-like structure and constituting an envelope surface with an opening facing the plane of the base plate 1. Because the opening of the envelope surface faces the plane of the base plate 1, the entire winding process is smoother, preventing the flexible solar cell array 300 from being stretched, wrinkled, or damaged during unfolding. During winding, the width of the opening gradually increases, enabling the unfolding arm 3 to elastically buckle, storing elastic potential energy. After the locking and release mechanism is released, the unfolding arm 3 returns to its center alignment state using the released elastic potential energy. During this process, the unfolding arm 3 gradually unfolds, driving the flexible solar cell array 300 to unfold synchronously, and providing longitudinal support along the unfolding direction for the unfolded flexible solar cell array 300.

[0047] A connecting mechanism 5 is provided between the unfolding arm 3 and the reel 2. The connecting mechanism 5 includes a connecting box 51, a rotating shaft 52, and a guide part 53. The connecting box 51 has a box opening 511. The rotating shaft 52 is rotatably disposed inside the connecting box 51, and one end of the rotating shaft 52 can pass through the connecting box 51 and be fixedly connected to the reel 2. The guide part 53 is disposed inside the connecting box 51 and is configured to guide the unfolding arm 3 to directionally pass through the box opening 511, so as to limit the interlayer relative shearing movement of the unfolding arm 3 during the release process. Understandably, one end of the unfolding arm 3 is fixed to the rotating shaft 52. During the winding process of the reel 2, the rotating shaft 52 can rotate accordingly, allowing the unfolding arm 3 to be wound around the rotating shaft 52. After winding, the connecting box 51 is fixed to the base plate 1 by the locking release component 41 of the locking release mechanism. During the unfolding stage, the locking release component 41 releases the lock on the connecting box 51, so that the elastic potential energy stored in the unfolding arm 3 is converted into kinetic energy to push the connecting box 51 to move. During this process, the rotating shaft 52 and the reel 2 rotate synchronously, so that the unfolding arm 3 unfolds synchronously with the flexible solar cell array 300. During the unfolding process, the unfolding arm 3 can abut against the guide part 53, thereby preventing the unfolding arm 3 from spreading in all directions, ensuring that the unfolding arm 3 is directionally passed through the box opening 51, realizing directional control of the unfolding arm 3, and improving the stability of the flexible solar cell array 300 during the unfolding process.

[0048] The guide section 53 includes multiple guide components, which are evenly distributed in a ring around the rotating shaft 52. Each guide component includes a connecting shaft 531 and a roller 532 sleeved on the connecting shaft 531. The roller 532 can abut against the unfolding arm 3 to reduce the friction between the guide section 53 and the unfolding arm 3.

[0049] It should be noted that the connecting mechanism 5 also includes a locking cylinder and a locking block disposed on the piston rod of the locking cylinder. The locking cylinder is disposed on the connecting box. After the unfolding arm 3 is wound, the locking cylinder extends, so that the locking block abuts against the unfolding arm 3, thereby locking the unfolding arm 3 wound on the rotating shaft 52.

[0050] In addition, a vertical plate is provided on the base plate 1 for connecting the unfolding arm 3 so that the two ends of the unfolding arm 3 are on the same plane when unfolded.

[0051] Furthermore, two deployable arms 3 are provided, distributed on both sides of the flexible solar array 300. This arrangement ensures that the ends of the scroll 2 are subjected to a stable driving force during movement, preventing the scroll 2 from shifting. This, in turn, ensures the stability of the flexible solar array 300 during deployment.

[0052] In practical applications, the scroll 2 is a hollow structure. This design can reduce the weight of the scroll 2, thereby further reducing the weight of the entire unfolding device 200. In addition, both ends of the scroll 2 are provided with connecting mechanisms 5 for connecting the unfolding arm 3.

[0053] The locking release mechanism includes a locking release component 41, which is disposed on the base plate 1 and configured to lock the connecting mechanism 5. It is understood that after the deploying arm 3 has finished retracting, the locking release component 41 can lock the connecting box 51 and can release the connecting box 51 when the deploying arm 3 needs to extend.

[0054] The locking and releasing assembly 41 includes a fuse coil and a locking block. The free end of the fuse coil can bypass the connecting mechanism 5 and connect to the locking block. The fuse coil is connected to an external power source, which is configured to energize both fuse coils to melt the fuse wires. It is understood that the fuse coils and the locking block are located on opposite sides of the base plate 1. After the unfolding arm 3 is wound up, the free end of the fuse coil can bypass the connecting box 51 and connect to the locking block to lock the connecting box 51 onto the base plate 1. When the unfolding arm 3 unfolds, the power source is energized to melt the fuse wires and release the connecting box 51.

[0055] Specifically, in this embodiment, two sets of locking and releasing components 41 are provided. The two sets of locking and releasing components 41 are located on both sides of the scroll 2 and are correspondingly set with the two connecting boxes 51. The two fuse coils are connected to the same external power source. When the unfolding arm 3 is unfolded, the power source simultaneously energizes the fuses of the two fuse coils, and the fuses on both sides melt simultaneously, thereby enabling both ends of the scroll 2 to switch from the locked state to the released state at the same time, and thus enabling both ends of the scroll 2 to move synchronously.

[0056] Furthermore, the locking and releasing mechanism includes multiple electromagnetic locking components connected to a power source, positioned between the flexible solar array 300 and the spacecraft. This locks the flexible solar array 300 onto the spacecraft after it has been wound up, preventing the deployable arm 3 from becoming disorganized. Preferably, the electromagnetic locking components are electromagnetic locks from the prior art.

[0057] In this embodiment, the flexible solar cell array 300 includes a substrate and solar cells evenly distributed on the substrate; the spool 2 is flat, and when the substrate is wound onto the spool 2, the solar cells can be stacked on the planar segment 21 of the spool 2. It is understood that the flat spool 2 can reduce the envelope size of the flexible solar cell array 300 after winding, reduce the space occupied, and meet the space requirements of small spacecraft.

[0058] For example, along the circumference of the spool 2, the outer contour surface of the spool 2 is alternately composed of two planar segments 21 and two opposing arcuate segments 22, and each solar cell can be stacked on the two planar segments 21 respectively. It is understood that the solar cells are spaced apart along the length of the substrate. When the spool 2 winds up the flexible solar cell array 300, the solar cells can be stacked on the two planar segments 21, and the areas of the substrate between two adjacent solar cells can be stacked on the two arcuate segments 22. This configuration guides the substrate to form a more regular winding shape during winding, thereby ensuring the stability and compactness of the flexible solar cell array 300 when it is in the winding state. Furthermore, at the initial moment of unfolding the flexible solar cell array 300, when the solar cells pressed at the bottom separate from the planar segments 21 of the spool 2, the contact surface separates flatly, rather than being "peeled" from the curved surface. This avoids asynchronous unfolding caused by local adhesion, laying a good foundation for the smooth and synchronous unfolding of the subsequent unfolding arm 3.

[0059] It should be noted that the substrate is composed of a glass fiber woven mesh and a polyimide film. The glass fiber woven mesh provides basic support for the substrate and serves as a mounting carrier for the flexible solar cell array 300. The solar cells are directly attached to the smooth, flat surface of the polyimide film using adhesive. However, because the polyimide film is laminated with the glass fiber mesh, during the winding process of the flexible solar cell array 300, the glass fiber mesh comes into contact with the solar cells on its back, which can easily lead to damage to the solar cells.

[0060] To this end, the flexible solar cell array 300 also includes polyimide foam, which is disposed on the back of the substrate. During the winding process, the polyimide foam can be compressed and filled between the solar cell and the flexible substrate to avoid the cells being squeezed by the glass fiber woven mesh, which could cause damage to the cells. When compressed, the polyimide foam can provide a preload pressure to compress the polyimide foam. During the unfolding process of the flexible solar cell array 300, the polyimide foam recovers its deformation and generates an outward expansion force to assist the unfolding of the flexible solar cell array 300 and improve stability.

[0061] In this embodiment, the base plate 1 includes a laminated aluminum panel, a honeycomb core, and an aluminum back plate; the aluminum panel and the honeycomb core, as well as the honeycomb core and the aluminum back plate, are connected by adhesives. The honeycomb core not only improves the load-bearing capacity of the base plate 1, but also achieves maximum weight reduction while ensuring the required rigidity and strength.

[0062] Based on the above, please refer to Figure 5 and Figure 6 This embodiment also proposes a spacecraft, which includes a drive unit 100 and two deployment / retraction devices 200 as described above, connected to the drive unit 100. The two deployment / retraction devices 200 are symmetrically arranged about the drive unit 100, and the drive unit 100 is configured to drive the two deployment / retraction devices 200 to rotate. A flexible solar array 300 is fixed to each of the two deployment / retraction devices 200. It is understood that the drive unit 100 can drive the two deployment / retraction devices 200 to rotate, thereby ensuring the flexible solar array 300 is oriented towards the sun to ensure power generation efficiency. The drive unit 100 is preferably a prior art SADA (Solar Array Drive Assembly), and because the two deployment / retraction devices 200 are symmetrically arranged about the drive unit 100, the stability of the solar array during deployment can be guaranteed.

[0063] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A retraction and deployment device for retracting and deploying a flexible solar cell array (300), characterized in that, include: The base plate (1) is fixed to one end of the flexible solar cell array (300); A spool (2) is fixed to the other end of the flexible solar cell array (300) and is configured to roll the flexible solar cell array (300) onto the base plate (1); The unfolding arm (3) is a thin-walled elastic composite material component. One end of the unfolding arm (3) is connected to the base plate (1). The unfolding arm (3) is configured to be flattened along its cross-sectional direction and wound on the spool (2) in the winding state to store elastic potential energy, and to use the elastic potential energy to drive the flexible solar cell array (300) to unfold after release. The locking and releasing mechanism is configured to lock the spool (2) and the unfolding arm (3) to the base plate (1) after the flexible solar cell array (300) is wound up, and to switch the spool (2) and the unfolding arm (3) from the locked state to the released state.

2. The retracting device according to claim 1, characterized in that, The deployable arm (3) is also configured such that, in the released state, its cross-section reverts to a non-planar tubular or trough-shaped structure to form a rigid arm, thereby providing longitudinal support along the deployment direction for the deployed flexible solar cell array (300).

3. The retracting device according to claim 1, characterized in that, A connecting mechanism (5) is provided between the unfolding arm (3) and the scroll (2), the connecting mechanism (5) comprising: The connecting box (51) has a box opening (511); A rotating shaft (52) is rotatably disposed inside the connecting box (51), and one end of the rotating shaft (52) can pass through the connecting box (51) and be fixedly connected to the scroll (2); A guide (53) is disposed inside the connecting box (51) and configured to guide the unfolding arm (3) to directionally pass through the box opening (511) to limit the interlayer relative shearing motion of the unfolding arm (3) during the release process.

4. The retracting device according to claim 3, characterized in that, The locking release mechanism includes a locking release component (41), which is disposed on the base plate (1) and configured to lock the connecting mechanism (5).

5. The retracting device according to claim 4, characterized in that, The locking release assembly (41) includes a fuse coil and a locking block, wherein the free end of the fuse coil can bypass the connecting mechanism (5) and connect to the locking block; The fuse coil is connected to an external power source configured to energize both fuse coils to melt the fuse wires of the fuse coils.

6. The retracting device according to claim 1, characterized in that, Two deployable arms (3) are provided and distributed on both sides of the flexible solar cell array (300).

7. The retracting device according to claim 1, characterized in that, The flexible solar cell array (300) includes a substrate and solar cells evenly distributed on the substrate; The spool (2) is flat, and when the substrate is wound on the spool (2), the battery cells can be stacked on the planar segment (21) of the spool (2).

8. The retracting device according to claim 7, characterized in that, The flexible solar cell array (300) also includes polyimide foam disposed on the back of the substrate.

9. The retracting device according to claim 1, characterized in that, The base plate (1) includes an aluminum panel, a honeycomb core and an aluminum back plate stacked together; The aluminum panel and the honeycomb core, as well as the honeycomb core and the aluminum back plate, are all connected by adhesives.

10. A spacecraft, characterized in that, The device includes a drive unit (100) and two retractable devices (200) as described in any one of claims 1-9 connected to the drive unit (100), the two retractable devices (200) being symmetrically arranged about the drive unit (100), the drive unit (100) being configured to drive the two retractable devices (200) to rotate; Both of the aforementioned retraction devices (200) are fixed with flexible solar cell arrays (300).

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