RU2356141C1 - Reflector of deployable antenna - Google Patents

Abstract

FIELD: physics, optics.

SUBSTANCE: invention may be used as large-size space collapsible reflector with parabolic or other curvilinear generatrix with diametre of several dozens metres. Reflector may be used as reflector of sunlight, for illumination of Earth surface during night time, as reflector of wave energy radiated by the Sun and as solar sail. Reflector comprises hub, radial spirally folding ribs with reflecting cloth fixed on them, shape-generating cloth, which is distantly located to reflecting one and connected to it by means of flexible strainers, closed belts are introduced in it made of two parts: internal - flexible and external - collapsible, internal belt is rigidly connected to ribs, and external belt is formed by elastic planks that are hingedly connected to ribs and to each other. Planks are hingedly connected to each other and two drawbars and have turn limiter. Cord with arresters is pulled through common hinged joints of planks and common drawbars. Cord together with external belt serves as carcass for fixation of shape-generating cloth. There is compression spring installed between common hinged joint of planks and common hinged joint of drawbars coaxially to cord. Number of radial ribs and belts is determined by necessary distance between shape-generating and reflecting cloth.

EFFECT: simplification of reflector design and reduced weight of structure.

5 dwg

Description

The invention relates to antenna technology and can be used as a large-sized space folding reflector with a parabolic or other curved generatrix with a diameter of several tens of meters. The reflector can be used as a parabolic antenna, a reflector of sunlight to illuminate the Earth's surface at night, as a reflector of wave energy emitted by the Sun, and as a solar sail.

Known deployable reflectors [1] - [3], containing the Central part and connected with it radial ribs: composite - [1] and elastic - [2] and [3]. The reflectors described in [1] and [2] have a low accuracy of reproduction of the paraboloid of rotation and are structurally complex, which limits the scope of their application. The reflector described in [3] is also complex, in addition, it represents only part of the useful area of the paraboloid.

Two-level structures are also known, containing reflective and forming webs, remotely located to each other and interconnected by flexible screeds, described in [4] - [7]. The disadvantages of the reflectors according to [4] - [6] are the small size ratios in the transport and deployed positions and the relatively large mass consumption per unit of reflector useful area. The disadvantages of the reflector described in [7] are: insecurity from meteor shower and additional energy consumption for maintaining the reflector in working condition, since the pressure in the inflatable, tubular support hoop must be within certain limits at significant temperature differences associated with work in outer space.

The closest in technical essence to the claimed invention is a large-sized space folding reflector [8] selected as a prototype, containing a hub, radial, spiral-wound ribs with a reflective cloth fixed to them, in addition, the reflector contains curved ribs, a tension drum, a framework, a mechanism deployment.

The disadvantages of this reflector are: low fidelity of the paraboloid (the reflecting surface is approximated by planes), the curved ribs are profiled in thickness, which together with the frames increases the dimensions of the reflector in the transport position, the presence of a deployment mechanism reduces the reliability of the opening of the reflector, and curved ribs increase the cost of design mass per unit of reflector useful area.

An object of the invention is to simplify the design of the reflector and the desire to obtain lower cost of mass of the structure per unit of useful area of the reflector.

The problem is solved in that closed belts are introduced, consisting of two parts: internal - flexible and external - folding. The inner belt is rigidly connected to the ribs, and the outer belt is formed by elastic trims pivotally connected to the ribs and to each other. Trims have a rotation limiter. On the planks are installed articulated thrusts with them, which are pivotally connected to each other. Through the common hinges of the slats and the general hinges of the rods, a cable with the stops fixed on it is passed. The cable, together with the outer belt, serves as a frame for fixing the forming fabric on it. A compression spring is installed coaxially with the cable between the common hinge of the slats and the common hinge of the rods. The number of radial ribs and belts is determined from the condition of ensuring the necessary distance between the forming and reflecting canvases.

The invention is illustrated by drawings, where figure 1 shows the reflector in the working position, figure 2 - reflector in the transport position (transport container not shown), figure 3 - reflector in the intermediate position, figure 4 - node a on an enlarged scale in the working position, figure 5 - node B on an enlarged scale in the working position.

The reflector comprises a hub 1, radial ribs 2, straps 3, hinges 4, 5, 6, 7, rods 8, a flexible belt 9, a reflective web 10, a cable 11, a forming web 12, flexible ties 13, a spring 14, an emphasis 15, limiters 16.

The hub 1 is a power element with which flexible radial ribs 2 are rigidly connected. In fact, the rib is a flat spring made of high strength steel or carbon fiber. The straps 3, made of the same material as the ribs, are connected by means of hinges 4 to the ribs and together and represent the outer (folding) part of the inserted belt. At the other end of the strap, they are joined by a hinge 5. Near this hinge there are rods 8 connected by a hinge 7 and connected to the straps 3 by hinges 6. A flexible belt 9 is passed through the hinges 4, which is the inside of the introduced belt. It is made of flexible material, such as a steel cable. The reflective fabric 10 is mounted on the ribs 2 and flexible belts 9 and is made, depending on the purpose, either of reflective or conductive material. Through the common hinges 5 of the strips and the general hinges 7 of the rods 8, a cable 11 is passed, which together with the strips 3 serves as a folding frame for fixing the forming fabric 12. The latter can be made of the same material as the reflector, or better of a material with more high modulus of elasticity. Flexible ties 13 bind reflective and forming materials. Their length, number and location determine the degree of approximation to the desired shape of the reflector. Between the hinges 5 and 7, a spring 14 is located coaxially with the portion of the cable 11. It is designed to fine-tune and hold the reflector 3 of the strips 3 in operating position. The stop 15, mounted on a cable, 11 serves to form a constant interference of the spring 14. The stops 16, made integral with the straps 3, prevent the rotation of the straps 3 from the working position.

In the collapsed position, the reflector is put into the orbit of the artificial satellite. After putting into orbit, the operation of deployment of the reflector is carried out. At the command of the control system, a transport container is opened. Under the action of the elastic forces of the ribs 2 and straps 3 are deployed and take the working position. In this case, the forming fabric stretched on the frame formed by the straps 3 and the cable 11, is straightened and through the flexible ties 13 brings the reflective fabric 10 into working condition.

The invention compared with the prototype increases the accuracy of the reproduction of a parabolic or other (cone, sphere, ellipsoid) reflective surface. The prototype reflective surface is approximated by planes, the number of which is limited by the number of radial and curved edges. In the present invention, the number of such planes is limited by the number of flexible ties. The absence of frames and curved, profiled along the thickness of the ribs reduces the dimensions of the reflector in the transport position. The absence of a deployment mechanism increases the reliability of the opening of the reflector. All of the above reduces the cost of structural mass per unit of useful area of the reflector and increases the coefficient of surface utilization. The proposed design can be made at enterprises specializing in the manufacture of space technology.

Information sources

1. US patent No. 3406404, NCI / US 343-915.

2. US patent No. 4608571, IPC 4 H01Q 15/20.

3. Russian patent No. 2093934, IPC 6 H01Q 15/20.

4. Japanese Patent No. 1-45762, IPC 4 H01Q 15/20.

5. Japanese Patent No. 3-17405, IPC 5 H01Q 15/20.

6. US patent No. 5864324, IPC 6 H01Q 15/20.

7. US patent No. 5990851, IPC 6 H01Q 15/20.

8. Russian Patent No. 2101811, IPC 6 H01Q 15/20.

Claims (1)

A reflector of a deployable antenna containing a hub, radially spirally coiled ribs with a reflective web fixed to them, a forming web remotely located to the reflective and connected with flexible screeds, characterized in that closed belts are introduced, consisting of two parts: internal - flexible - and the outer one is folding, the inner belt is rigidly connected to the ribs, and the outer belt is formed by elastic strips pivotally connected to the ribs and between themselves, the strips have a rotation limiter, on the mouth bars the rods hingedly connected to them, hingedly connected to each other, a cable with fixed stops is passed through the common hinges of the slats and the common hinges of the rods, the cable together with the external belt serves as a frame for fixing the forming fabric on it, between the common hinge of the slats and the common hinge of the rods a compression spring is installed coaxially with the cable, the number of radial ribs and belts is determined from the condition of ensuring the necessary distance between the forming and reflecting canvases.

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