Large-aperture spatial columnar deployable thin film light shield

Abstract

The invention belongs to the technical field of spaceflight, and particularly relates to a large-aperture spatial columnar deployable film light shield. According to the technical scheme, the large-caliber space columnar unfoldable thin film light shield comprises an unfoldable supporting mechanism and a thin film, the unfoldable supporting mechanism has the axial folding and unfolding functions, and the shape of the unfoldable supporting mechanism in the unfolding state is an irregular dodecagonal cylindrical surface with the upper portion beveled; the thin film is connected with the inner side of the extensible supporting structure and is folded and unfolded in the axial direction along with the extensible supporting structure. The large-aperture spatial columnar deployable film light shield provided by the invention can meet the development requirements of complex optical equipment, large field of view and wide band of an optical system, light weight of a deployable structure and high storage rate.

Description

Technical Field

[0001] The invention belongs to the field of aerospace technology, and in particular relates to a large-caliber space columnar deployable film sunshade. Background Art

[0002] With the development of aerospace technology and the increasing demand and requirements for deep space exploration, space optical telescopes are gradually developing in the direction of large field of view, wide band, and high quality. For space optical systems, stray light and external heat flow in complex space environments are important factors that affect the success or failure of their missions. The space light shield is a protective device installed at the front end of the optical equipment of the spacecraft. It can avoid the influence of stray light input and temperature changes on the equipment, provide a good working environment for the space optical system, and is an important guarantee for the space telescope to successfully complete high-quality imaging tasks.

[0003] According to the geometric shape, the light shield structure can be divided into cylindrical light shield, flat light shield and conical light shield. Among them, cylindrical light shield mainly includes regular prism and cylindrical surface, flat light shield mainly includes square, V-shaped and circular, and conical light shield includes regular pyramid and conical surface. According to whether it has the function of folding and unfolding, it can be divided into fixed light shield and deployable light shield. Fixed light shield is mostly small in size due to the limitation of rocket fairing; while deployable light shield is folded during launch and unfolded after entering orbit, which is more in line with the future development trend of large caliber and lightweight. According to the driving mode, deployable light shield can be divided into motor drive, inflation drive and elastic self-expanding drive. Motor drive is precise and controllable, but it will bring problems such as weight increase and increased structural complexity; inflation drive can greatly reduce the structural mass, but the inflation rigidification technology is not mature enough, and the light shield has low deployment accuracy, low rigidity and difficult shape maintenance. Elastic self-expanding drive relies on the elastic drive of the material itself, does not require an external power source, and has high deployment accuracy.

[0004] Research on sunshades at home and abroad has achieved many research results and practical applications. Northrop Grumman Corporation of the United States designed a hexagonal prism-shaped deployable film sunshade for the International X-ray Observatory (IXO) telescope, which is driven to unfold the film by axial extension of three sets of extension arm structures. QinetiQ of the United States has developed a beveled hexagonal prism-shaped deployable film sunshade. The sunshade first controls the base support arm to unfold through a motor-driven rope, and then the main tube structure drives the upper connection structure to unfold under the action of the elastic hinge. The JWST telescope jointly developed by NASA and ESA is equipped with a V-shaped flat sunshade, which is the largest deployable film sunshade in history. It uses a combined bracket with a fixed axis rotation and a variable diameter sleeve rod to realize the unfolding of a 5-layer film structure under the drive of a motor. NASA has developed a beveled hexagonal pyramid sunshade structure for the large space telescope ST-9. The sunshade structure is driven to unfold 5 layers of film synchronously through 6 variable diameter telescopic rods. Zhejiang University has designed a cylindrical inflatable deployable sunshade, which consists of an inflatable circular tube, an inflatable straight tube and a thin film structure, and can achieve orderly expansion in the axial and radial directions.

[0005] In summary, as the demand and requirements of space exploration missions increase, the number and size of space optical equipment will increase, which will in turn increase the complexity and scale of space optical systems. However, the current sunshade structures are mostly regular in shape, mostly cylinders, regular prisms, planes or cones, and are small in size, which makes it difficult to meet the needs of complex shapes of future optical equipment and large fields of view and wide bands of space telescopes. Considering the limitations of rocket launch space and weight, there is an urgent need for a new type of sunshade with lightweight and high storage rate. Summary of the invention

[0006] The present invention provides a large-aperture spatial columnar deployable film sunshade, which can meet the development requirements of complex optical equipment, large field of view, wide band of optical system, lightweight deployable structure and high storage rate.

[0007] The technical solution of the present invention is as follows:

[0008] A large-caliber spatial columnar expandable film sunshade comprises an expandable support structure and a film. The expandable support structure has the functions of axial folding and unfolding, and its shape in the unfolded state is an irregular dodecagonal cylinder with an oblique cut on the upper part; the film is connected to the inner side of the expandable support structure and axially folds and unfolds with the expandable support structure.

[0009] Furthermore, the large-aperture spatial cylindrical expandable film sunshade, the expandable supporting mechanism includes a lower cylindrical part and an upper beveled part, the lower cylindrical part is formed by multiple cylindrical modules vertically connected along the height direction, and the upper beveled part is formed by beveled module one, beveled module two, beveled module three and beveled module four vertically connected in sequence along the height direction.

[0010] Furthermore, the large-aperture spatial cylindrical expandable film sunshade, the cylindrical module includes two closed rib frames and eight sets of folding rod structures, the closed rib frame is an irregular dodecagonal frame, the two closed rib frames are connected by eight sets of folding rod structures; two adjacent cylindrical modules share one closed rib frame.

[0011] Furthermore, the large-caliber spatial columnar expandable film sunshade, the bevel module one includes six sets of folding rod structures and a bevel rib frame one, the bevel rib frame one is an open irregular eleven-sided frame, and the bevel rib frame one is connected to the closed rib frame located at the uppermost end of the lower cylindrical part through the six sets of folding rod structures; the bevel module two includes six sets of folding rod structures and a bevel rib frame two, the bevel rib frame two is an open irregular nine-sided frame, and the bevel rib frame two is connected to the bevel rib frame one through the six sets of folding rod structures; the bevel module three includes four sets of folding rod structures and a bevel rib frame three, the bevel rib frame three is an open irregular nine-sided frame, and the bevel rib frame three is connected to the bevel rib frame two through the four sets of folding rod structures; the bevel module four includes two sets of folding rod structures and a bevel rib frame four, the bevel rib frame four is an open irregular heptagonal frame, and the bevel rib frame four is connected to the bevel rib frame three through the two sets of folding rod structures.

[0012] Furthermore, the large-aperture spatial columnar expandable film sunshade, the folding rod structure includes a root hinge, a lower folding rod, a middle hinge, an upper folding rod and a top hinge, one end of the lower folding rod is connected to the root hinge, and the other end is connected to the middle hinge; one end of the upper folding rod is connected to the middle hinge, and the other end is connected to the top hinge.

[0013] Furthermore, the large-aperture spatial cylindrical expandable film sunshade, the middle hinge includes a main shaft, a torsion spring 1, a male hinge, a female hinge, a locking hook, a pin shaft, a return spring and a locking plate; the male hinge and the female hinge form a rotating pair through the main shaft, and a limit block is provided at the contact position between the female hinge and the male hinge; a torsion spring is set on the main shaft, and the two ends of the torsion spring 1 are respectively connected to the male hinge and the female hinge; the middle part of the locking hook is rotatably connected to the female hinge through the pin shaft, and a return spring is provided between the tail of the locking hook and the female hinge, and the locking plate is arranged on the male hinge, and the head of the locking hook corresponds to the position of the locking plate; the male hinge is connected to the upper folding rod, and the female hinge is connected to the lower folding rod.

[0014] Furthermore, the large-aperture spatial cylindrical expandable film sunshade has a root hinge and a top hinge structure that are the same, both of which include a base, a connecting piece, a rotating shaft, two torsion springs, a tightening spring and a positioning pin; the base and the connecting piece form a rotating pair through the rotating shaft, the two torsion springs are sleeved on the rotating shaft, and the two ends of the two torsion springs are respectively connected to the base and the connecting piece; a blind hole is provided on the side of the connecting piece, the tightening spring is arranged in the blind hole, the positioning pin is connected to the tightening spring, a self-locking positioning hole is provided on the side of the base, the axis of the positioning pin and the center of the self-locking positioning hole are both located on the same circumference with the rotating shaft as the center, and the end of the positioning pin matches the size of the self-locking positioning hole; the connecting piece is provided with a bolt for connecting the lower folding rod or the upper folding rod.

[0015] Furthermore, the large-caliber space columnar expandable film sunshade is composed of a composite of an aluminum-plated polyimide film, a polyester mesh and a black sunshade cloth.

[0016] Furthermore, the large-caliber spatial columnar expandable film sunshade is folded based on the Accordion origami model when the film is retracted, and is expanded under the drive of the expandable support mechanism.

[0017] Furthermore, the large-aperture spatial columnar expandable film sunshade and the expandable support mechanism are installed at the front end of the optical instrument compartment, and the optical instrument compartment is equipped with a solar cell panel to provide power guarantee.

[0018] The beneficial effects of the present invention are:

[0019] 1. The present invention adopts a design scheme of combining a rigid deployable support mechanism and a flexible film. While ensuring the overall rigidity of the sunshade, it fully utilizes the advantages of the film's light weight and large folding / expansion ratio to meet the needs of large-scale, lightweight and large folding / expansion ratio space optical equipment.

[0020] 2. The overall structure of the sunshade of the present invention adopts a modular design scheme, which effectively improves the versatility, flexibility and expandability of the structure. By changing the shape, size, number and combination and arrangement of the modules, the size of the sunshade structure can be quickly changed to meet the future large-scale development needs.

[0021] 3. The film of the present invention is folded using the Accordion origami model, which can maintain good coordination with the deployable support mechanism while meeting the shape and size requirements, thereby achieving an axial deployment function.

[0022] 4. The hinge in the expandable support mechanism of the present invention adopts a torsion spring self-locking hinge, which is driven by the elastic potential energy stored in the torsion spring. This driving method does not require an external driving source, reduces the weight of the overall structure, has a simple and reliable structure, and can achieve limit locking after being unfolded into place.

[0023] 5. The large-aperture space-expandable film sunshade proposed by the present invention is installed at the front end of the optical system to prevent the influence of external heat flow and light radiation on the space optical equipment. Some of the technologies are not only applicable to the field of aerospace technology, but also have high reference and reference value in the fields of foldable houses, foldable awnings and large outdoor buildings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the spacecraft's sun shield in a folded state;

[0025] Figure 2 This is a schematic diagram of the unfolded state of the sun shield on the spacecraft;

[0026] Figure 3 Schematic diagram of the unfolding process of a large-aperture space cylindrical unfoldable film sunshade; (a) is the folded state, (b) is the semi-expanded state, and (c) is the unfolded state;

[0027] Figure 4 It is a schematic diagram of the cylindrical module;

[0028] Figure 5 is a schematic diagram of a bevel cutting module;

[0029] Figure 6 This is a schematic diagram of the bevel module 2;

[0030] Figure 7 It is a schematic diagram of the bevel module three;

[0031] Figure 8 It is a schematic diagram of the bevel cutting module four;

[0032] Fig. 9 is a schematic diagram of a folding rod structure;

[0033] Fig.10 is a schematic diagram of the middle hinge;

[0034] Fig.11 This is a schematic diagram of the root (top) hinge;

[0035] Fig.12 Schematic diagram of film crease distribution; among them, (a) is the cylindrical module part, (b) is the bevel module part one, (c) is the bevel module part two, (d) is the bevel module part three, and (e) is the bevel module part four. DETAILED DESCRIPTION

[0036] like Figure 1-11As shown, a large-caliber space columnar expandable film sunshade includes an expandable support mechanism and a film 4. The expandable support mechanism has the function of axially folding and unfolding, and its shape in the expanded state is an irregular dodecagonal cylinder with an upper bevel cut; the film 4 is connected to the inner side of the expandable support structure, and axially folds and unfolds with the expandable support structure. The expandable support mechanism is installed at the front end of the optical instrument chamber 2, and the optical instrument chamber 2 is equipped with a solar panel 3 to provide power guarantee.

[0037] The expandable support mechanism includes a lower cylindrical part and an upper beveled part. The lower cylindrical part is formed by three cylindrical modules connected vertically in the height direction, and the upper beveled part is formed by beveled module 1, beveled module 2, beveled module 3 and beveled module 4 connected vertically in sequence in the height direction. The cylindrical module includes two closed rib frames 5 and eight sets of folding rod structures 10. The closed rib frames 5 are irregular dodecagonal frames. The two closed rib frames 5 are connected by eight sets of folding rod structures 10. Two adjacent cylindrical modules share one closed rib frame 5. The bevel module one includes six sets of folding rod structures 10 and a bevel rib frame one 6, the bevel rib frame one 6 is an open irregular eleven-sided frame, and the bevel rib frame one 6 is connected to the closed rib frame 5 located at the uppermost end of the lower cylindrical part through the six sets of folding rod structures 10; the bevel module two includes six sets of folding rod structures 10 and a bevel rib frame two 7, the bevel rib frame two 7 is an open irregular nine-sided frame, and the bevel rib frame two 7 is connected to the bevel rib frame one 6 through the six sets of folding rod structures 10; the bevel module three includes four sets of folding rod structures 10 and a bevel rib frame three 8, the bevel rib frame three 8 is an open irregular nine-sided frame, and the bevel rib frame three 8 is connected to the bevel rib frame two 7 through the four sets of folding rod structures 10; the bevel module four includes two sets of folding rod structures 10 and a bevel rib frame four 9, the bevel rib frame four 9 is an open irregular heptagonal frame, and the bevel rib frame four 9 is connected to the bevel rib frame three 8 through the two sets of folding rod structures 10.

[0038] The folding rod structure 10 includes a root hinge 15, a lower folding rod 14, an intermediate hinge 13, an upper folding rod 12 and a top hinge 11. One end of the lower folding rod 14 is connected to the root hinge 15, and the other end is connected to the intermediate hinge 13; one end of the upper folding rod 12 is connected to the intermediate hinge 13, and the other end is connected to the top hinge 11.

[0039] The middle hinge 13 includes a main shaft 23, a torsion spring 24, a male hinge 21, a female hinge 22, a lock hook 26, a pin 28, a return spring 29 and a lock plate 27; the male hinge 21 and the female hinge 22 form a rotating pair through the main shaft 23, and a limit block 25 is provided at the contact position between the female hinge 22 and the male hinge 21; the torsion spring 24 is sleeved on the main shaft 23, and the two ends of the torsion spring 24 are respectively connected to the male hinge 21 and the female hinge 22; the middle part of the lock hook 26 is rotatably connected to the female hinge 22 through the pin 28, and a return spring 29 is provided between the tail of the lock hook 26 and the female hinge 22, and the lock plate 27 is arranged on the male hinge 21, and the head of the lock hook 26 corresponds to the position of the lock plate 27; the male hinge 21 is connected to the upper folding rod 12, and the female hinge 22 is connected to the lower folding rod 14. When the middle hinge 13 is fully retracted, the torsion spring 24 stores elastic potential energy; when it is unfolded, the torsion spring 24 releases the elastic potential energy to drive the male hinge 21 and the female hinge 22 to rotate around the main axis 23; when it is close to being fully unfolded, the lock hook 26 gradually contacts the lock plate 27; when it is fully unfolded, the limit block 25 of the female hinge 22 presses against the male hinge 21, and the return spring 29 pushes the lock hook 26 to hook the lock plate 27, thereby achieving a locked and limited state.

[0040] The root hinge 15 has the same structure as the top hinge 11, and both include a base 31, a connecting member 32, a rotating shaft 33, a second torsion spring 34, a tensioning spring and a positioning pin 35; the base 31 and the connecting member 32 form a rotating pair through the rotating shaft 33, the second torsion spring 34 is sleeved on the rotating shaft 33, and the two ends of the second torsion spring 34 are respectively connected to the base 31 and the connecting member 32; a blind hole is provided on the side of the connecting member 32, and the tensioning spring is arranged in the blind hole, the positioning pin 35 is connected to the tensioning spring, and a self-locking positioning hole 36 is provided on the side of the base 31, the axis of the positioning pin 35 and the center of the self-locking positioning hole 36 are both located on the same circumference with the rotating shaft 33 as the center, and the end of the positioning pin 35 matches the size of the self-locking positioning hole 36; the connecting member 32 is provided with a bolt 37 for connecting the lower folding rod 14 or the upper folding rod 12. When the root hinge 15 or the top hinge 11 is fully retracted, the torsion spring 34 stores elastic potential energy; when unfolded, the torsion spring 34 releases elastic potential energy to drive the connecting member 32 to rotate around the rotating shaft 33; when rotated into place, the positioning pin 35 pops out and is inserted into the self-locking positioning hole 36 under the action of the tightening spring, thereby achieving locking and limiting.

[0041] The film 4 is composed of aluminized polyimide film, polyester mesh and black shade cloth; the aluminized polyimide film arranged on the outermost side plays a role in heat preservation and heat insulation; the polyester mesh can separate the multiple layers of aluminized polyimide film, thereby making the film more fluffy to prevent heat transfer; the innermost black shade cloth is used to block stray light and prevent light reflection. Fig.12As shown, the film 4 is folded based on the Accordion origami model when it is folded, and is unfolded under the drive of the unfoldable support mechanism.

[0042] The working process is as follows: in the initial state, the expandable support mechanism and the film 4 are completely folded and pressed, and the torsion springs 1 24 and 2 34 in the root hinge 15, the top hinge 11 and the middle hinge 13 store elastic potential energy; when expanding, the torsion springs 1 24 and 2 34 release the elastic potential energy to twist and drive the lower folding rod 14 and the upper folding rod 12 to rotate, and the folding rod structure 10 expands axially and drives the closed rib frame 5, the beveled rib frame 1 6, the beveled rib frame 2 7, the beveled rib frame 3 8 and the beveled rib frame 4 9 connected to the folding rod structure 10 to expand axially; when the expandable support mechanism is expanded, the film 4 connected thereto is also expanded synchronously; after the expandable support mechanism is expanded into place, locking and limiting are achieved, and finally an irregular dodecagonal cylindrical structure with an upper bevel is formed.

Claims

1. A large-diameter space columnar expandable film sunshade, characterized in that: It includes an expandable support structure and a film. The expandable support structure has the function of axial folding and unfolding, and its shape in the expanded state is an irregular dodecagonal cylinder with an oblique upper portion. The film is connected to the inner side of the expandable support structure and axially folds and unfolds with the expandable support structure.

2. The large-aperture space columnar expandable film sunshade according to claim 1, characterized in that: The expandable support mechanism includes a lower cylindrical part and an upper beveled part, the lower cylindrical part is formed by a plurality of cylindrical modules vertically connected along the height direction, and the upper beveled part is formed by beveled module one, beveled module two, beveled module three and beveled module four vertically connected in sequence along the height direction.

3. The large-aperture space columnar expandable film sunshade according to claim 2, characterized in that: The cylindrical module comprises two closed rib frames and eight sets of folding rod structures. The closed rib frame is an irregular dodecagonal frame. The two closed rib frames are connected by the eight sets of folding rod structures. Two adjacent cylindrical modules share one closed rib frame.

4. The large-aperture space columnar expandable film sunshade according to claim 3, characterized in that: The bevel module one includes six sets of folding rod structures and a bevel rib frame one, the bevel rib frame one is an open irregular eleven-sided frame, and the bevel rib frame one is connected to the closed rib frame located at the uppermost end of the lower cylindrical part through six sets of folding rod structures; the bevel module two includes six sets of folding rod structures and a bevel rib frame two, the bevel rib frame two is an open irregular nine-sided frame, and the bevel rib frame two is connected to the bevel rib frame one through six sets of folding rod structures; the bevel module three includes four sets of folding rod structures and a bevel rib frame three, the bevel rib frame three is an open irregular nine-sided frame, and the bevel rib frame three is connected to the bevel rib frame two through four sets of folding rod structures; the bevel module four includes two sets of folding rod structures and a bevel rib frame four, the bevel rib frame four is an open irregular heptagonal frame, and the bevel rib frame four is connected to the bevel rib frame three through two sets of folding rod structures.

5. The large-aperture space columnar expandable film sunshade according to claim 4, characterized in that: The folding rod structure includes a root hinge, a lower folding rod, a middle hinge, an upper folding rod and a top hinge. One end of the lower folding rod is connected to the root hinge and the other end is connected to the middle hinge; one end of the upper folding rod is connected to the middle hinge and the other end is connected to the top hinge.

6. The large-aperture space columnar expandable film sunshade according to claim 5, characterized in that: The middle hinge comprises a main shaft, a torsion spring 1, a male hinge, a female hinge, a locking hook, a pin shaft, a return spring and a locking plate; the male hinge and the female hinge form a rotating pair through the main shaft, and a limit block is provided at the contact position between the female hinge and the male hinge; a torsion spring is set on the main shaft, and the two ends of the torsion spring 1 are respectively connected to the male hinge and the female hinge; the middle part of the locking hook is rotatably connected to the female hinge through the pin shaft, and a return spring is provided between the tail of the locking hook and the female hinge, and the locking plate is arranged on the male hinge, and the head of the locking hook corresponds to the position of the locking plate; the male hinge is connected to the upper folding rod, and the female hinge is connected to the lower folding rod.

7. The large-aperture space columnar expandable film sunshade according to claim 5, characterized in that: The root hinge has the same structure as the top hinge, and both include a base, a connecting piece, a rotating shaft, two torsion springs, a tightening spring and a positioning pin; the base and the connecting piece form a rotating pair through the rotating shaft, the two torsion springs are sleeved on the rotating shaft, and the two ends of the torsion springs are respectively connected to the base and the connecting piece; a blind hole is provided on the side of the connecting piece, the tightening spring is arranged in the blind hole, the positioning pin is connected to the tightening spring, a self-locking positioning hole is provided on the side of the base, the axis of the positioning pin and the center of the self-locking positioning hole are both located on the same circumference with the rotating shaft as the center, and the end of the positioning pin matches the size of the self-locking positioning hole; the connecting piece is provided with a bolt for connecting the lower folding rod or the upper folding rod.

8. The large-aperture space columnar expandable film sunshade according to claim 1, characterized in that: The film is composited by aluminum-plated polyimide film, polyester net and black light-shielding cloth.

9. The large-aperture space columnar expandable film sunshade according to claim 1, characterized in that: The film is folded based on the Accordion origami model when it is gathered, and is unfolded under the drive of the unfoldable support mechanism.

10. The large-aperture space columnar expandable film sunshade according to claim 1, characterized in that: The deployable support mechanism is installed at the front end of the optical instrument compartment, and a solar cell panel is installed on the optical instrument compartment to provide power guarantee.

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