JPS61232705A - Antenna system for artificial satellite - Google Patents

Abstract

PURPOSE:To make smaller and thinner the system in the folding-up condition by dividing respective mirror surface parts into three positions, storing to the rocket in the condition folded-up to the U-shape when the artificial satellite is launched, and developing so that the parts may go to parabolic mirror surfaces after launching. CONSTITUTION:A main reflection mirror 13 is stored at the upper part of a launching rocket in the condition fitted through a hinge device 20 to a tower 12 of an artificial satellite 11 beforehand. By the command from a ground station, etc., at the processes to launch and go around on the orbit, the main reflection mirror 13 folded up to the U-shape so as to surround the tower 12 is released from the first holding device 17, both mirror surface parts B are rotated almost to 90 deg. in the direction of an arrow with a rotating supporting shaft 15a as a supporting point, and developed up to the position to form the parabolic surface together with a mirror surface part A. Next, after the time is late a little, the second holding device of the third hinge device 20 is operated, and the main reflecting mirror 13 is developed from the tower 12. Thus, the parabolic antenna with a large area can be loaded into the rocket body.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides a deployable antenna reflector suitable for use on board an artificial satellite, etc., which can be stored in a rocket when launched by a rocket to Dlj. [Technical background of the invention and its problems] Recently, reflectors with a large diameter and high mirror surface accuracy have been used as reflectors for onboard satellites. The desired 0 satellite is transported to outer space by a launch vehicle, but the outer diameter of the rocket is generally small, and the rocket is subject to a large acceleration load during flight, so in the case of a large diameter antenna, it is necessary to fold it into a small size and at the same time properly It is necessary to support the entire structure and prevent structural damage.

Conventionally, there have been two types of deployable antenna reflectors: one that folds a highly flexible mirror surface (mesh film, etc.) and one that folds a rigid mirror surface that has high mirror precision.
The former is suitable for large-scale applications, but it is difficult to improve mirror surface accuracy, and the frequency band used is several GHz.
Subject to the following restrictions. Temporary placement is suitable for use in high frequency bands, which are expected to become mainstream in the future, but it is of the so-called center feed type, for example, the mirrored end is divided into petal-like parts, each facing towards the center. Some can be assembled into a cylindrical shape.

For example, there are those shown in FIGS. 11 to 13. That is, in FIG. 11, (1) is a boundary portion divided into petal-like parts, each of which is folded in the radial direction and stored. (2) is a frame that supports the parabolic antenna; (3) is a hinge that supports the mirror part (1); and (4a) is a cable that holds the outer mirror part (1) when stored. FIG. 12 shows the state in which the outer border (1) is unfolded when stored, and s (4b) is a cable that holds the inner border (1). FIG. 13 shows the state after the expansion is completed, and (5) is the central mirror surface attached to the frame (2).

When the cable (4a) is cut with a blast tube type cutter or the like, the outer mirror portion (1) is expanded by the force of the expansion spring of the hinge (3) and launched at a predetermined position. Next, the cable (4b) holding the inner mirror surface part (1) is cut with a cutter with a blast tube, etc., and when stored, the cable (4b) holding the inner mirror surface part (1) is cut.
1) is deployed and launched, and the deployment of the parabolic antenna is completed.

In order to deploy this type of conventional antenna as described above,
It is suitable for rotationally symmetrical printing surfaces, but is not originally suitable for storage and deployment of rotationally asymmetric structures such as offset mirror surfaces, and requires multiple deployment mechanisms by dividing the mirror surface into many parts. There was a drawback.

[Purpose of the invention]

The present invention has been made in view of the above points, and aims to reduce the size and thickness of the folded state as much as possible, improve storability in a rocket, and create an offset system particularly suitable for use in artificial satellites. This invention relates to a feed antenna that employs such a deployment mechanism.

[Summary of the invention]

In other words, each mirror surface is divided into three parts, and when the satellite is launched, it is folded into a U-shape and stored in the rocket, and after launch, it can be expanded to become a parabolic mirror surface. be.

[Embodiments of the invention (configuration)]

An embodiment of the present invention shown in FIGS. 1 to 1o will be described below. αυ is an artificial satellite main body, and a pyramid-shaped antenna support tower α2 (hereinafter referred to as a tower) is provided integrally with the main body of the satellite. It will be done.

A main reflecting mirror 0 is provided at the bottom of this tower α2, and a sub-reflecting mirror I is provided at the top, thereby configuring an offset feed antenna.

As shown in FIG. 1, the main reflecting mirror 0 has three mirror parts: a central reflecting mirror part (hereinafter referred to as mirror part A) and both reflecting mirror parts (hereinafter referred to as @ surface part B). It is configured as a parabolic surface, and truss assemblies Al and Bt are constructed as shown in FIGS. 3 to 6 based on the basic truss assembly configuration shown in FIG. 7. In other words, these mirror surfaces A and B are formed by a large number of trusses A2... and B2.
... are assembled by a large number of joints A3... and B3... In addition, X... is a latch device (details omitted) that acts at various places between the mirror surface part and the mirror surface part B connection part when both mirror surface parts B are expanded to become parabolic mirror surfaces. This allows the parabolic surface to be maintained mechanically expanded. Then, on this parabolic surface, a reflective thin film A4. B4 is to be stretched. The plurality of trusses A2..., B2..., joints A3... and each reflective thin film A4. B4 is made of advanced composite materials such as CFR and P (carbon fiber reinforced plastic).
It is a lightweight and high-strength member using materials such as Mposite Materials.

As shown in FIGS. 3 and 4, each of these mirror surfaces A and B is connected to a first hinge device (! They are connected by two sets of second hinge devices (!J) provided.

When using the first hinge device, the rotation support shaft (1000)
sa) is a position appropriately inward from the side edge of the mirror surface portion A (hereinafter referred to as an off-cent position), and is also located within the support structure for the mirror surface portion. And this rotation support shaft (
In 15a), an arm (15bt) extends from a position opposite to the mirror surface part B.

(15b2) and the coaxial end of the rotational support shaft (15a), the rotational support shaft (15a) is coaxially attached to the rotational support shaft (isa) so that the rotational support shaft (15a) is constantly rotated in the direction in which the mirror surface portion B is expanded. It is equipped with a coil spring (lsb) wound around the mirror, and the mirror surface part B rotates freely in the direction of the solid line arrow (FIGS. 5 and 6) from the state shown in FIGS. 5 and 6. As shown in Figure 3, it forms a parabolic surface.

Note that when the other first hinge device is in a symmetrical position, the explanation will be omitted since it has a symmetrical relationship with the first hinge device described above.
, U is 0 in which the rotation support shafts (1sa) and (16a) of the first hinge device (!5.◎) are coaxial, and the rotation support shaft (16
an arm (16bt), (tsb
2) and a coil spring (16c) coaxially wound around the rotation support shaft (16a) so as to rotate the rotation support shaft (16a).
b) The other second hinge device located at the symmetrical position, which works in cooperation with the first hinge device, will not be explained because it has a symmetrical relationship with the first hinge device. @... is a first holding device for the mirror surface part B that is disposed protrudingly opposite to both the mirror surface parts B at the tip of the tower αa, and this is a first holding device for the mirror surface part B, which is located at the tip of the tower αa, as shown in FIG.
It is attached to a holder (11) extending from the holder (illustrated in phantom line), and is connected and fixed to the holder facing the joint part on the free end side of the mirror surface part B.

At this time, the mirror surface part B is attached to open freely against the acting force of the coil spring (15b) of the first hinge device [Co., Ltd.] and the coil spring (16c) of the second hinge device [Co., Ltd.]. . That is, this first holding device is a holding tool a
Bolt catcher (18b) on the metal fitting (18a) side of No.8
Nut holder (18) with built-in pyro (18e)
c), and on the other side of the mirror surface part B, there is provided a joint B3 located in the same position as the bolt catcher (18b) and equipped with a bolt (18d).
As shown in FIGS. 8 to 10, the shaft seat (1sc) is provided in a slightly stretched position on the rotation support side of the mirror surface part B via the arms (15bt) and (15bz).

- On the kaleidoscope A side, as shown in Fig. 10, the shaft seat (
A bearing seat (isi) is provided at the same central position as the shaft seat (15C), and the mirror surface portion B is rotatably supported by this bearing seat (xsi) via the shaft seat (15C).

The bearing seat (15i) is attached to the truss A2 as shown in FIG.
The fixing member (15d) fixed through the fixing member (15d) is supported so that an urging force is applied in the direction of the arrow. The fixing member (
15d) is provided with a second holding device 0 similar to the first holding device αη. In this case, the mirror surface part A is a nut holder (15e).

0 held on the tower (1 wharf) via the support arm (15f)
Inside the nut holder (15e), like the aforementioned Nando holder (18C), there is a Nando holder (15e) with a built-in bolt catcher (05g) and Bi-O (15h).
is provided, and does not operate after the mirror part B is deployed until it is further deployed from the tower living room 2 as described later. As shown in Figs. 1 and 2, the main reflector can be deployed in the direction of the arrow with respect to the tower (L), that is, from the state in Fig. 1 to the state in Fig. 2. A third hinge device is provided between the side of the second hinge device and the tower α.This third hinge device [phase] is installed radially from the base (20a). The arms (20b) to (zoe) extending to connect the joints A3 of the mirror part A to the arms (zob) to (20e) at the ends of the mirror part A, and further connect the base ( 20a) is a coil spring (zo
g), and when the second holding device υ operates, the holding is released, and the main reflecting mirror 0 is moved to the position shown in FIG.
It operates so that a biasing force is applied in the direction of the arrow, that is, in the unfolding direction, from the state of the antenna, that is, the folded state of the antenna.

[Embodiments of the invention (effects)]

The present invention is constructed as described above, and its operation will be explained next.

In the state shown in Figure 2, the main reflector ◎ is installed in advance on the tower 〇 of the artificial satellite αυ via the third hinge device [Co., Ltd.] and is stored at the top of the launch vehicle (illustrated by the imaginary line). Ru. This is launched by a rocket into, for example, a geostationary orbit. After being launched, the antenna is deployed in response to a command from a ground station while orbiting. In other words, the main reflector U, which is folded into a U-shape to surround the tower as shown in Figs. The first holding device @ is released.

That is, the pyro (18e) is activated by the command signal, the bolt catcher (18b) is destroyed by the detonation action, and the bolt (18d) and the nut (not shown) are disengaged. In addition, this first holding device ■ is such that a total of four first holding devices 0, including those provided symmetrically on one mirror surface portion B and those on the other mirror surface portion B, operate simultaneously. It is something to do. This first holding device 0...
With the release of *, both mirror parts B rotate approximately 90 degrees in the direction of the arrow in FIGS. 5 and 6 using the rotation support shaft (15a) as a fulcrum and then stop. In other words, the coil springs (is
Due to the actions of b) and (16b), the rotating force is applied, and the state shown in FIG. 8 is changed to the first hinge device located on the rotation support shaft as shown in FIG. 9 (15G). and the bearing seat (15υ) of the mirror surface part B as a fulcrum,
(The end side of the hinge device operates in the same way, so the explanation will be omitted.) Together with the mirror surface section, it is expanded to a position forming a parabolic surface as shown in FIG.

Then, the parabolic surface is maintained expanded by the operation of the launch device X.

Next, with a slight delay due to the operation of the first holding device 0, the third hinge device (or the second holding device 0) is activated, and the state held by the tower (La) is released. , as shown in Fig. 2, the main reflecting mirror ◎ is deployed from the tower α2.

That is, in response to a command from the ground station, the second holding device 0, like the first holding device 0, is activated by the bolt catteyer (15g) due to the detonation effect caused by the operation of the pyro (xsh) shown in FIG. Destroyed, Pol) (15
j) The bond with Nando (not shown) is lost. Note that a description of the other second holding device 0 located at the symmetrical position will be omitted. When the NAND comes off in this way, the spring (20g) of the third hinge device [Co., Ltd.] will apply a biasing force to the main reflecting mirror 0 in the direction of expansion as shown by the arrow in Figure 2. . Then, the bolt attached to the mirror surface A side is released from the second holding device 1. Therefore, the main reflection ml is the tower U as shown in FIGS. 3 and 6.
It is expanded to a predetermined position (relative position to the sub-reflector I) shown in FIG. 1 by the action of a coil spring (20g) using the rotation support shaft (20h) as a fulcrum.

〔Effect of the invention〕

As described above, the present invention provides a central reflecting mirror surface portion A.

Folding reflective mirror parts B and B'Ir:a are provided on both sides of the mirror so as to be foldable via hinge devices, and when folded, the mirror parts are folded into a U-shape to surround the tower of the satellite body. Therefore, when this type of antenna is mounted, the tower can be housed in the so-called dead space that is created around the tower, and a parabolic antenna with as large an area as possible can be installed within the limited size of the rocket body. It is possible to carry an artificial satellite with a

Furthermore, in the hinge device according to the present invention, since the rotation support shaft of the folding reflective mirror part is provided at an offset position from the joining part of the mirror parts A and B, the entire area occupied when stored in the folded state can be reduced, and the space occupied by the tower can be reduced. The gap can be made very small, and in particular, the offset position or dimension can be appropriately determined depending on the width dimension, ie, L dimension, of the trap and antenna support tower, as shown in FIG. Therefore, the gaps between the mirror parts A and B and the antenna support tower can be greatly reduced, in other words, the dead space can be utilized more, and it can be stored compactly, especially in a limited area inside the rocket. It is something that can be done.

Furthermore, since the off-cent position is located inward by a dimension of '' on the side projection plane of the mirror surface section A, this hinge device itself can be mounted within the wall surface of the mirror surface section A, thereby eliminating dead space. It is possible to make use of the following information.

Historically, the folding reflective mirror section is provided with a spring device that is always biased in the unfolding direction, and the trap tower is provided with a holding mechanism that always holds the folding reflective mirror surface in the folded state. Since the folded reflective mirror parts are automatically unfolded when the rocket is released, when the rocket is launched, each of the reflective mirror parts has sufficient strength to withstand the impact caused by the launch of the rocket held against the tower. This is something you can prepare for.

[Brief explanation of drawings]

Figures 1 to 10 are diagrams showing the present invention. Figure 1 is a perspective view of the main parts of the satellite with the antenna expanded, and Figure 2 is a side view of the main parts of the satellite with the antenna folded. , 3rd
The figure is a rear view of the antenna body in the unfolded state, Figure 4 is a rear view of the antenna body of Figure 3 in the folded state, Figure 5 is a view taken along the X-arrow view of 7th
The figure is a perspective view of the truss assembly in the antenna deployment state, FIG. 8 is an enlarged perspective view of the antenna device shown in the direction of the arrow in FIG. FIG. 10 is an enlarged perspective view of the second part of FIG. 8, which is a perspective view of a main part showing a state in which the antenna is unfolded. Figure 11~
Fig. 13 shows a conventional example, Fig. 11 shows a folded state of the antenna, Fig. 12 shows a partially unfolded state, and Fig. 13 shows a state after completion of unfolding. be. αυ: Satellite body, σ2: Antenna support tower, 0: Main reflector, σno: Sub-reflector, Kasumi: First hinge device, 4: Second hinge Device, 0...
First holding device, holding device, U... second holding device, [Co., Ltd.]... third hinge device % A... central reflective mirror surface section, B... folding mirror surface Section, A1. Bt...
Truss assembly, A2゜B2...Truss, A3. B3...
Joint, A4. B4...Reflector film, X...2-point device. Agent Patent attorney Noriyuki Chika (and 1 other person) Figure 6 1ad

Claims (3)

[Claims] (1) It has a central reflective mirror surface portion, and foldable reflective mirror surface portions that are foldably provided on both sides of the central reflective mirror surface portion via a hinge device,
When this folding reflective mirror part is folded,
An artificial satellite characterized in that it is U-shaped so as to surround an antenna support tower of a main body of the artificial satellite, and the rotational support shaft of the hinge device is located at an offset position from the joint between the central reflective mirror surface part and the folding reflective mirror surface part. antenna device. (2) The antenna device for an artificial satellite according to claim 1, wherein the offset position is located within a support structure of the central reflecting mirror surface. (3) The folding reflective mirror section is provided with a spring device that is always biased in the unfolding direction, and the antenna support tower is provided with a holding mechanism that always holds the folding reflective mirror surface in the folded state; 3. An antenna device for an artificial satellite according to claim 1, wherein the folded reflective mirror surface section is automatically unfolded when the folding mirror surface section is released.