JPH0533561B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a deployable antenna reflector, particularly one suitable for use on a satellite.

[Prior Art] FIGS. 1, 2, and 3 show an example of a conventional deployable antenna reflector.

Here, FIG. 1 shows its stored state, and FIGS. 2 and 3 show its expanded state.

The deployable antenna reflector shown in FIGS. 1, 2, and 3 is formed in a so-called parasol shape, and a large number of ribs 2 are arranged radially from a disk-shaped central dish 1, and between each rib 2. A flexible conductive thin film 4 is stretched. Each rib 2 is
Its base end is connected to the central dish 1 in the above-mentioned disk shape via a hinge 3 having one degree of freedom. The flexible conductive thin film 4 is made of, for example, a fine metal mesh.

Here, in the stored state shown in FIG. 1, the ribs 2 are contracted, so that the flexible conductive thin film 4 is folded between the ribs 2. In addition, in the unfolded state shown in FIGS. 2 and 3, the ribs 2 expand radially, thereby causing the flexible conductive thin film 4 to
is developed between each rib 2 with a slight tension, thereby forming a parabolic radio wave reflecting mirror surface.

However, the above-mentioned conventional deployable antenna reflector first requires a storage length that is approximately 1/2 of its deployed diameter. For this reason, its storability was not necessarily good.

Furthermore, although each rib 2 itself is formed to curve along a predetermined parabolic plane, the flexible conductive thin film 4 developed between each rib 2 is Due to the slight tension exerted on the surface, the surface tends to flatten without following the parabolic surface. For this reason, the mirror surface precision inevitably becomes rough. In order to approximately improve this mirror precision, the only way is to increase the number of the ribs 2 as much as possible. However, increasing the number of ribs results in a significant increase in weight, which is a trade-off.

[Summary of the Invention] This invention was made to improve the above-mentioned drawbacks, and by using wires instead of the ribs described above, it is possible to improve the storage property, improve the accuracy of the radio wave reflecting mirror surface, and reduce the weight. This paper proposes a deployable antenna reflector that can achieve both of the following.

[Embodiment] FIGS. 4 to 7 show a deployable antenna reflector according to an embodiment of the present invention.

Here, FIGS. 4 and 5 are a front view and a side view showing the state when stored. Also, the 6th
FIG. 7 is a front view and a side view showing the unfolded state.

The deployable antenna reflector shown in FIGS. 4 to 7 includes hinges 11a, 11b, a long beam 12a, and a short beam 1.
2b, a support wire 13, a flexible conductive thin film 14, a bonding wire 15, and the like. Further, it can be attached to the side wall 22 of the satellite main body using accessory parts such as a spacer 16, a fixture 17, a column hinge 18, a column bar 19, a column spacer 20, and a column fixture 21.

The hinges 11a and 11b are each equipped with a spring device such as a spiral spring, and are always elastically biased in the direction of expansion. It is also equipped with a latch device so that it is locked when expanded to a predetermined angle. in this case,
One hinge 11a is locked at an expansion angle of 180 degrees, and the other hinge 11b is locked at an expansion angle of 120 degrees.

The long beams 12a and the short beams 12b are each tubular rods made of, for example, carbon fiber composite material. The long beam 12a and the short beam 12b are connected in an annular manner by the hinges 11a and 11b to form a polygonal (regular hexagonal) hoop as shown in FIG. This polygonal hoop is attached on one side to the satellite side wall 22 by a fixture 17. In this case, the long beams 12a are arranged on the side located on the attachment side to the satellite side wall 22 and on the side opposite to the side. Two short beams 12b are arranged on each of the other sides (four sides). Short beam 12b
are formed to have approximately half the length of the long beam 12a, and are arranged with two connected on each side.
The corners of the polygonal hoop are connected by hinges 11b that expand to 120 degrees. Also, the distance between the short beams 12b and 12b is 180
They are each connected by a hinge 11a that expands at the same time (see FIG. 6).

The long beam 12a and each hinge 11a, 11b
As shown in FIG. 6, one end of a support wire 13 is fixed to each of the supports. Each support wire 13
The other ends are each fixed to the peripheral edge of the flexible conductive thin film. The flexible conductive thin film 14 is made of, for example, a fine metal net. Moreover, its planar development shape is formed into the same polygon (regular hexagon) as the polygonal hoop. This flexible conductive thin film 14 is expanded by being pulled in the plane direction via the support wire 13.

As shown in FIG. 7, one end of each of a large number of engagement wires 15 is distributed and fixed to the surface of the flexible conductive thin film 14. As shown in FIG. The other end of each bonding wire 15 is concentrated in one place and fixed to the tip of the column bar 19.

The column bar 19 is a column foldable by a hinge 18, and its base is fixed to the satellite side wall 22 by a column fixture 21. As shown in FIGS. 4 and 5, the column bar 19 is designed to be stored even when it is folded and laid down on the side of the satellite side wall 22.
The satellite side wall 22 has the column bar 1 in its stored state.
A column spacer 20 for supporting the column 9 is attached. Further, the column bar 19 has a sixth column bar 19.
As shown in FIG. 7 and FIG. 7, it is extended to stand vertically with respect to the satellite side wall 22. Then, the tip thereof is located at the same height as the center of the hoop, and the other end of the bundled bonding wire 15 is pulled from this position.

Note that the hinge 18 is also provided with a spring device and a latch device. This allows that hinge 1
8 is always elastically biased in the expansion direction. It also locks when expanded to 180 degrees.

Now, the operation of the deployable antenna reflector will be explained.

First, at the time of satellite launch, the hoop and the column bar 19 are folded by bending them at the hinges 11a, 11b, and 18, respectively, as shown in FIGS. 4 and 5. At the same time, the flexible conductive thin film 14 is also folded into the hoop. At this time, the long beam 12a is formed to be slightly longer than twice the length of the short beam 12b. This prevents the left and right hinges 11a from colliding with each other when the hoop is folded. Also, the folded beam 1
A spacer 16 is interposed between each of the beams 2a and 12b, thereby maintaining a predetermined gap between each beam 12a and 12b.
Even in the folded state as described above, it is secured and stored in the side wall 22 of the satellite by an appropriate binding condition (not shown).

Next, when the launched satellite reaches a predetermined orbit, the binding by the binding device is released. As a result, as shown in FIGS. 6 and 7, the hinges 11a, 11b, 18 are each expanded to a predetermined angle by the action of the spring device and locked. Then, the flexible conductive thin film 14 spreads together with the hoop, and as a result, the bonding wire 1
5 also expands. At the same time, the column bar 19
rises from the satellite side wall 22 at a right angle, and its tip pulls the other end of the coupling wire 15 rearward. As a result, the flexible conductive thin film 14 is stretched in three axial directions and expanded into a parabolic shape. Then, an antenna reflector is formed.

Here, even when the peripheral edge of the flexible conductive thin film 14 is pulled radially in the surface direction from the hoop via the support wire 13, the flexible conductive thin film 14 has a large number of fastening points distributed on its surface. By being pulled backward by a large number of bonding wires 15,
It is designed to be expanded into a predetermined parabolic shape. The shape of the curved surface is determined by the length of each bonding wire 13, and the mirror-like precision of the curved surface is determined by the number of fixing points per unit area of a large number of bonding wires 15 fixed to the conductive thin film 14, or ,
It depends on the number of bonding wires 15. Therefore, only the number of bonding wires 15 are used to obtain the required curved surface damping, but what should be noted at this time is that the bonding wires 15 are smaller than the ribs of a conventional parasol-like deployable antenna reflector. and 1
The weight per book can be made very light, and since it is made of wire, it can be bent completely freely.
Therefore, the approximation accuracy of the radio wave reflecting mirror surface of the antenna reflector can be improved by increasing the number of antenna reflectors without significantly increasing the weight. Moreover, the storage property can also be made very good.

In the above embodiment, the shape of the hoop is a regular hexagon, but the same effect can be obtained by using other regular polygonal shapes or irregular polygonal shapes. Further, the bonding wire 15 may be made of either metal or non-metal. Furthermore, the column bar 19 can be omitted if there is a suitable place to fasten the other ends of a large number of bonding wires. Furthermore, the other ends of the large number of bonding wires may be fixed at a plurality of locations or in a dispersed manner.

[Effects of the Invention] As explained above, the present invention uses a wire in place of the rib as a member that defines the curved surface of the deployable antenna reflector, thereby improving the storage property and improving the accuracy of the radio wave reflecting mirror surface. It is possible to achieve both improvement and weight reduction.
There is an effect.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a conventional deployable antenna reflector in its retracted state, FIGS. 2 and 3 are front and side views respectively showing its deployed state, and FIGS. 4 and 5 are one example of the present invention. FIGS. 6 and 7 are a front view and a side view showing a state in which the deployable antenna reflector according to the embodiment is stored, and FIGS. 6 and 7 are a front view and a side view showing a state in which it is deployed. In the figure, 11a, 11b, 18 are hinges,
12a, 12b long beams and short beams, 13 is a wire,
14 is a flexible conductive thin film, 15 is a bonding wire, 19
is a column bar, and 22 is a side wall of the satellite. In addition,
The same reference numerals in each figure indicate the same or equivalent members.

Claims (1)

[Claims] 1. A deployable antenna reflector in which a folded flexible conductive thin film is deployed into a predetermined curved shape, and a foldable hoop that is deployed by pulling the flexible conductive thin film in the direction of its surface; ,
A large number of bonding wires fixed to a large number of locations distributed on the surface of the flexible conductive thin film and a hoop having the flexible conductive thin film are provided separately, and the entire flexible conductive thin film is fixed to a predetermined area. pulled backwards with a tension of
1. A deployable antenna reflector comprising a bonding wire focusing means for fixing the other end of the bonding wire so that the flexible conductive thin film has a predetermined curved surface shape.