JPS6249705A - Deployable antenna reflector - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a deployable antenna reflector, and particularly to the structure of a deployable antenna mounted on, for example, an artificial satellite or a space station.

[Conventional technology]

WXI diagram, Figure 8, and Figure 9 are 1, for example, JP-A-59-
It was disclosed in Publication No. 28704. They are a side view when unfolded, a front view when unfolded, and a front view when stored, showing a conventional deployable antenna reflector. In each of the above figures, 11a is a hinge that has a built-in elastic spring such as a spiral spring that provides the driving force for rotation, and is equipped with a latch device that locks the rotation when a predetermined rotation angle is reached. The hinge prisoner-11b that latches at is the same hinge that latches at a deployment angle of 135 degrees: ) (B), where each hinge (
A) 11 m and hin:) (B)llb can be configured to incorporate a bearing that can realize low friction conditions, and this bearing is, for example, a spherical bearing. 12a and 12b are tubular members 1 whose ends are connected to each other by hinges (A) 11 a and hinges (B) 1 l b, and which form a hoop shape as a whole; for example, a tubular length made of carbon fiber composite material. frame and a short frame - the long frame 12& is provided at the attachment point to the satellite body 18 and at a position opposite thereto on the hoop.

Other than that, a hoop shape is formed by the short frame 12b. 13 is a long frame 12a and each hinge (A) 1
111 eHinge (B) 1 l bHolded with v4 adjustable tension by a number of support wires mounted on it. Reference numeral 14 denotes two mesh-like flexible thin films whose edges are supported by a large number of support wires 13, and at least one of which is conductive. Reference numeral 15 refers to two opposing flexible thin films 14 that are connected inwardly to each other. The length of the bonding wire is adjustable. 16
17 is a fixture for fixing the long frames 12& to the satellite main body 18.

A conventional deployable antenna reflector is constructed as described above, and at the time of launch, as shown in FIG.

Connect the ends to each hinge (A) l 1 a # hinge (B) 1
The ninth long frame 12a and the short frame 1 are connected by lb.
A hoop consisting of 2b is attached to each of the above hinges (A) 11 &
, is folded at the hinge (B) llb. Here, as shown in FIG. A) To prevent IIJL from colliding with each other - 2 of the length of the other short frame 12b
It has been slightly longer than twice. 9. A large number of connecting wires 1 are provided inside the hoop via a large number of supporting wires 13.
Two mesh-like flexible thin films 14 connected to each other at 5
Ha, Bancho.

It is folded between short frames 12a and 12b.

In this state, each adjacent long and short frame 12a,
The spacers 16 provided on the spacers 12b are fixed to the satellite main body 18 in a state in which they abut each other and are bound by a suitable binding device (not shown). and.

After arriving in orbit, when the above bonding device is released, each hinge (
A) 111L, each long and short frame 12a, 12b begins to expand due to the torque of an elastic spring such as a thinly coiled spring built into the hinge (B) llb, and along with this, each long and short frame 123. The two flexible thin films 14 folded between 12b also begin to unfold. Here, the hinge (A) that is folded inward when stored is 11 m.
is locked by a built-in latch device when the deployment angle reaches 180 degrees lζ.

Also, the hinge (B) that was folded outward 1 lb
teeth.

It is locked by a built-in latch device when the deployment angle reaches 135 degrees. Thus, every each hinge (A)l
la, when the hinge (B) 11b is locked.

As shown in FIG. 8, it is finally formed into an octagonal hoop. In this state, the length of each support wire 13 is adjusted in advance so that the two mesh-like flexible thin films 14 connected by a large number of bonding wires 15 are applied with a predetermined tension, and thereby Form the required parabolic surface.

[Problem that the invention seeks to solve]

Since the conventional deployable antenna reflector described above is configured as described above, when the satellite performs attitude control in orbit, the fluctuation acts on the antenna reflector through the satellite body 18 as a disturbance. At this time, since the mirror surface of the antenna reflector is formed by the mesh-like flexible thin film 14, its rigidity is extremely low.Therefore, there is a problem in that the parabolic surface is greatly deformed and the mirror surface accuracy is significantly reduced. Ta.

This invention was made to solve this problem, even when the antenna is subjected to disturbance.

The purpose of the present invention is to obtain a deployable antenna reflector that can maintain a highly accurate mirror surface and also has excellent shrinkability.

[Means for solving problems]

A deployable antenna reflector according to the present invention.

It is composed of a rib made of a variable three-dimensional truss structure that can be expanded and contracted, and a flexible conductive thin film that provides the desired shape as an antenna reflector.

[Effect]

In the deployable antenna reflector of the present invention, the rigidity is increased by attaching ribs to the mirror surface of the antenna reflector, thereby preventing large deformation of the parabolic surface due to disturbances.
In other words, the mirror surface precision is prevented from deteriorating, and furthermore, by forming the ribs into a variable three-dimensional truss structure that can be extended and contracted, it is possible to achieve excellent shrinkability.

〔Example〕

Figures 1, 2, and 3 are a front view when unfolded, a side view when unfolded, and a side view when stored, showing a deployable antenna reflector that is an embodiment of the present invention. .1
8 is the same as the above conventional example. In each of the above figures, -14' is a flexible conductive thin film, 19 is a central tissue having the required mirror precision, and 20 is a rib that is arranged radially from the central dish 19 and is made of a variable three-dimensional truss structure that can be expanded and contracted. 21 is a holding device that connects each rib 20 and the central dish 19.

4 and 5 are perspective views showing a part of the shape of the ribs constituting the deployable antenna reflector shown in FIG. 1 when they are retracted and when they are extended, and FIG. It is a perspective view showing the variable truss member of the variable three-dimensional truss structure which constitutes a rib. In each of the above figures, 22 is a hinge that incorporates an elastic spring such as a spiral spring that provides the driving force for rotation, and is equipped with a latch device that locks the rotation when a predetermined rotation angle is reached; 23 is a hinge in the longitudinal direction of the rib 20; Diagonal member-2 constituting
Reference numeral 4 denotes an extensible and contractible transverse member that constitutes a plane perpendicular to the longitudinal direction of the rib 20. Reference numeral 25 indicates a pipe-shaped outer cylinder that constitutes the transverse member 24. Reference numeral 26 indicates a pipe-shaped inner cylinder, and 27 28 is an elastic spring, and 28 is a latching device that locks the transverse member 24 when it is retracted.

Next, the operation of the deployable antenna reflector which is an embodiment of the invention described above will be explained.

During launch, the diagonal members 23 and the transverse members 24 that cover the ribs 20 of the deployable antenna reflector are folded at each hinge 22, as partially shown in FIGS. In a tightly bound state, it is held in the central dish 19 via the holding device 21, and further.

It is fixed to the satellite main body 18 by a fixture 17 . here,
A flexible conductive thin film 14' attached to each rib 20 is folded between each rib 2o. Also.

The elastic spring 27 of the transverse member 24 has one end at the end of the member,
The other end is fixed to the end of the inner cylinder 26 and stored in a stretched state. After reaching the orbit, when the binding device is released, the inner tube 26 is nested inside the outer tube 25 due to the restoring force of the elastic spring 27 built in the transverse member 24. and is locked by the latch device 28. At this time, each horizontal member 2
4 becomes shorter than the initial state, each diagonal member 23, which was folded in a plane when stored, lifts up three-dimensionally, and the rib 20 begins to expand. Diagonal member 2
3 reaches a predetermined angle, it is locked by a latch device 28 built into the hinge 22, resulting in the variable space truss structure shown in FIG.

Here, by appropriately determining the length of the transverse member 24, an arbitrary curvature can be obtained as a variable space truss structure. Therefore, by employing a transverse member 24 of an appropriate length, ribs 20 having the required curvature as shown in FIGS. 1 and 2 can be extended and formed. The attached flexible conductive thin film 14' spreads out as each rib 20 stretches, forming the desired parabolic surface in its final position. Here, the details of the unfolding mechanism of the variable space truss structure can be found in the US literature, N.A.S.A. Covference publ.
cation2311 r l 8THAERO8P
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See M.J.

In addition, in the above embodiment, the case where the deployable antenna reflector is mounted on the satellite main body 18 is shown.

The present invention can be applied to a so-called free flyer in which the antenna alone floats in space, and also to a large-diameter antenna constructed at a space base, and the same effects as in the above embodiment can be achieved.

Further, in the above embodiment, the antenna reflector is circular and the following case is shown, but the present invention can also be applied to a non-circular antenna, for example, an offset antenna, and the same effects as in the above embodiment can be obtained in this case as well.

〔Effect of the invention〕

As explained above, the present invention is a deployable antenna reflector in which the antenna reflector is configured to form a desired parabolic surface by a rib made of a variable three-dimensional truss structure that can be expanded and contracted, and a flexible conductive thin film. The rigidity of the parabolic surface is increased, and large deformation of the parabolic surface due to disturbance can be prevented.1. This has the excellent effect of providing a deployable antenna reflector that maintains extremely high mirror surface accuracy and has good H injection.

[Brief explanation of drawings]

1, 2, and 3 are a front view when unfolded, a side view when unfolded, and a side view when stored, showing a deployable antenna reflector that is an embodiment of the present invention; FIG. FIG. 5 is a perspective view showing a part of the shape of the ribs forming the expandable antenna reflector shown in FIG. 1 when retracted and extended; FIG. 6 shows a part of the ribs forming the ribs shown in FIGS. 4 and 5; FIG. FIGS. 7 and 8 are perspective views showing variable truss members of a variable three-dimensional truss structure. and FIG. 9 are a side view when unfolded, a front view when unfolded, and a front view when stored, showing a conventional deployable antenna reflector. In the figure, 14'...flexible conductive thin film, 17...
Attachment, 18... Satellite body, 19... Central dish - 20... Rib - 21... Hold! Place, 22
... Hinge, 23 ... Diagonal member, 24 ... Lateral member, 25 ... Outer cylinder, 26 ... Inner cylinder - 27 ... Elastic spring, 28 ... Latch device . In each figure, the same reference numerals indicate the same or similar parts.

Claims (3)

[Claims] (1) A deployable antenna reflector comprising a rib made of a variable three-dimensional truss structure that can be expanded and contracted in the axial direction and a flexible conductive thin film, and is configured to be deployed into a desired curved shape. (2) the variable space truss structure consists of a tubular member;
The deployable antenna reflector according to claim 1, wherein this member is made of a carbon fiber composite material. (3) The deployable antenna reflector according to claim 1 or 2, wherein the curvature of the curved surface formed by the variable three-dimensional truss structure is adjustable.