JPH0465563B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a deployable antenna suitable for being mounted on a satellite, which has a small shape when mounted on a satellite, and which operates as a large aperture antenna when deployed in space. This relates to a set antenna.

<Prior Art> Conventionally, this type of antenna has the configuration shown in FIG. In FIG. 1, the left half shows the state before the antenna is expanded, and the right half shows the state after the antenna is expanded.

A holding base 13 is rotatably attached to the attachment portion 11 of the antenna to the satellite structure via a joint 12. One end of the radial rib 1a is attached to the holder 13, and one end of each of the radial ribs 1b to 1d and 1b' to 1d' on both sides of the radial rib 1a is attached to the holder 13 via a joint 14, respectively. Radial ribs 1a, 1b to 1d,
1b' to 1d' are each curved in one plane, and when the antenna is unfolded, these ribs form a radial shape approximately centered on the holding base 13, and are curved to the same side to follow the mirror surface of the antenna. . A joint 14 allows the radial ribs 1b to 1d, 1b' to 1d' to be rotated toward or away from the central radial rib 1a. Adjacent ones at the other ends of the radial ribs 1a, 1b to 1d, 1b' to 1d' are sequentially connected by a lateral rib 15, and the intermediate portions of the ribs 1a, 1b to 1d, 1b' to 1d' are also sequentially connected. They are connected by transverse ribs 16. Each of these transverse ribs 15, 16 can be bent or extended by knee hinges 17, 18 containing springs at their midpoints. Radial ribs 1a, 1b~1
d, 1b' to 1d', a conductive mesh 19 forming an antenna mirror surface is stretched over the lateral ribs 15, 16.

Next, an outline of the development of this antenna is shown in FIG. Deployment of the antenna is initiated by commands from the ground. As shown in FIG.
radial ribs 1b~1d, 1b'~
1d' are fixed to the satellite body (not shown) in substantially parallel proximity to each other in an unexpanded state. From this state, the end of the antenna 21 is separated from the satellite structure by operating the pyrotechnics in response to a command from the ground, and the spring is moved around the joint 12 to the predetermined antenna state 21' (Fig. 2B). The first stage of deployment is completed by rotating and fixing using force or the like.

The second stage of deployment begins when the fixing device of the radial rib (not shown) is released on command from the ground. Radial ribs 1b to 1d, 1
When the fixing devices b' to 1d' are released, the transverse rib 1
5 and 16 are stretched to open and the radial rib 1
b to 1d, 1b' to 1d' are expanded. With each lateral rib 15, 16 fully extended, the knee hinge 1
7, 18 are fixed, and the radial ribs 1b to 1d,
The expansion of 1b' to 1d' is completed, and the state shown in FIG. 2C is reached, and the second stage of expansion is completed. This completes the deployment of the antenna.

In this way, in the conventional deployable offset antenna, the antenna is deployed through two stages: transition from state A to state B in Figure 2, and transition from state B to state C in Figure 2. It is necessary to ensure sufficient deployment reliability, and the configuration makes it difficult to obtain high reliability in antenna deployment.

<Summary of the Invention> An object of the present invention is to provide a deployable antenna that can deploy the antenna in one motion and improve reliability when deploying the antenna.

Another object of the present invention is to provide a deployable antenna that can stably obtain a slow rib deployment speed with a lightweight device.

According to the present invention, the radial rib can be rotated within each of its constituent planes, and this rotation allows the antenna to be deployed in one movement, and the deployment speed can be easily and stably slowed down.

<Example> FIG. 3 shows the state of the antenna of the embodiment of the present invention before deployment, and FIG. 4 shows the state after deployment, and the same reference numerals as in FIGS. 1 and 2 are given. shall refer to the same thing. FIG. 3A is a plan view of the antenna of this embodiment in a housed state, and FIG. 3B is a front view. The antenna holding part 23 is fixed to a satellite structure (not shown), and one end of a plurality of ribs 24 is attached to the holding part 23 by a joint 25, respectively. A mesh 19 is stretched between the plurality of ribs 24, which becomes a mirror surface of the antenna when the ribs 24 are expanded. The joints 25 are arranged in a substantially arc shape on the holding part 23. Each of the ribs 24 can rotate about a joint 25 in a plane substantially perpendicular to the arcuate plane in which the joints 25 are arranged. Figure 3 A and B
As shown in FIG. 2, when the antenna is not deployed, the ribs 24 are substantially parallel and close to each other. FIG. 3C is a perspective view showing one of the ribs 24 and the structure in the vicinity of its joint 25. The other ribs 24 also have a similar structure. One end of a wire 33 is attached to the rib 24, and by pulling the wire 33, the rib 24 rotates in the direction of the arrow. Further, a spring (not shown) is attached to the rotation shaft of the joint 25. When the wire 33 is not pulled by this spring force, it is in the stored state as shown in FIG. 3C. The detailed structure and operation of the vicinity of the joint 25 will be described later with reference to FIG.

The fourth image shows the state after rotating the rib 24 and expanding it.
Shown in Figures A and B. Each rib 24 as shown
are expanded radially, and the mesh 19 stretched between the ribs 24 is stretched so as to form a mirror surface of the antenna. Note that by forming the rib 24 into an appropriately curved shape as shown in FIGS. 3B and 4B, the shape of the mesh can be made into the shape required for the mirror surface of the antenna.

FIG. 5 shows a detailed structure in the vicinity of the joint portion 25. The linear spring 32 is the holding part 2
3. It is installed between the ribs 24, but this spring 3
2 is configured such that the spring force becomes stronger when the ribs 24 are rotated to expand. Wire 33 to rib 24
One end of the wire 33 is attached, and the wire 33 is mounted on a roller 34, which is provided as necessary for smooth operation.
It has been introduced into the satellite for this purpose. wire 33
is configured to be wound up and pulled by a motor or the like provided within the satellite body. Also,
A latch pin 29 is provided on the rib 24, and a pin hole 31 is provided at a location corresponding to the position where the rib 24 is fully expanded.

Next, a specific procedure for deploying the antenna of this embodiment will be explained.

The unexpanded antenna shown in FIG. 3A is locked by a fixing device (not shown) that fixes the radial rib 24 and is fixed to the satellite structure. To deploy the antenna, a command from the ground activates the pyrotechnics and separates one end of the antenna that is fixed to the structure. Next, the fixing device for the rib 24 is released using a pyrotechnic device or the like. Next, when the wires 33 attached to each rib are simultaneously pulled by a motor etc., the plurality of ribs 24 are moved from A to B in Fig. 5.
→Turn in the order of C, from the rib 24 to the latch pin 29.
falls into the pin hole 31 by the force of the spring inserted into the small hole in the side of the rib 24, and the rib 24 is fixed in that position. The rotating portion 25 of each rib 24 has a similar structure, and when each rib opens and expands, each wire 33 is rotated so that the direction of each rib is almost the same.
pull. After the ribs are expanded, each rib 24 is attached to the holding part 2
The mesh 19 is fixed in a radial manner with the mesh 19 as the center, and the antenna is completely expanded to the state shown in FIG. 4, and the mesh 19 forms a mirror surface of the antenna.

With this configuration, the wire 33
When the wire 33 is pulled, the rib 24 rotates against the force of the spring 32, so the rib 24 can be gradually rotated by adjusting the force of pulling the wire 33. That is, the deployment speed of the antenna can be adjusted arbitrarily. Therefore, according to the configuration of the present invention, the antenna can be expanded slowly, and can be expanded without applying a strong load to the long ribs.

As shown in FIG. 4, by sequentially tensioning the tension members 35 on the free ends of the ribs 24, when the mesh is developed to a mirror surface, the rotation of the ribs 24 is not aligned, so that a part of the mesh 19 is strongly pulled and damaged. It is possible to prevent such an overload, and to prevent the rib from vibrating and the mesh 19 from being torn when controlling the attitude of the satellite. The tension member 35 may also be provided on the joint 25 side. Also, mesh 19 in the state before the antenna is deployed.
In order to maintain a constant shape, the transverse ribs 15, 16 (or only 15) shown in FIG. 1 may be used in the antenna of the present invention. In this case, the springs in the knee hinges 17, 18 may be omitted.
The horizontal ribs 15 and 16 are not limited to being bent inside the antenna opening as shown in FIG. 1, but may also be bent outward to maintain the mesh shape before expansion.

The rib 24 may be rotated by the joint 25 not only at the position where it is attached to the holding portion 23, but also at a position further away from this.

<Effects> As explained above, in the deployable antenna of the present invention, the offset antenna can be deployed with one action of rotating the radial ribs radially.
Unlike conventional offset antennas, it is not necessary to perform the two movements of rotating the radial ribs all together and then expanding them, so the antenna has the advantage of being easy to deploy and having high reliability.

Also, the expansion speed of the ribs is adjusted by the wire 33 and the spring 32.
By combining these, it is possible to stably adjust to a slow state with a lightweight device. Furthermore, when the rib is expanded, the rib is received by the stopper at a predetermined position, and in this state, the latch pin of the rib is automatically inserted into the pin hole of the holding part, and the expanded state is fixed, meaning that the antenna is always A predetermined unfolded state is achieved, and the unfolded state is stably maintained.

[Brief explanation of the drawing]

Figure 1 is a front view showing a conventional deployable antenna.
FIG. 2 is a diagram showing the deployment order of a conventional deployable antenna, and FIG. 3 is a diagram showing an example of the deployable antenna of the present invention in a state before deployment, where A is a plan view, B is a front view, and C is a single Configuration diagram of the rib and its holding part No. 4
The figure shows the unfolded state of the antenna in Figure 3,
5 is a plan view, B is a front view, and C is a configuration diagram of one rib and its holding portion. FIG. 5 is a diagram showing an example of a joint portion in the deployable antenna of the present invention. 19...Mesh forming antenna mirror surface, 2
3... Holding part, 24... Rib, 25... Joint between rib and holding part, 29... Latch pin,
33...Wire.

Claims (1)

[Scope of Claims] 1. A plurality of ribs having a curved shape so as to form a part of the antenna mirror surface in an expanded state, and each rib is arranged substantially radially, and
a holding part that rotatably holds each rib while keeping the curved direction of each rib in the same direction; a spring that is wound around the rotational shaft of each rib and applies rotational force to the rib; A pin hole provided in the holding portion; a stopper provided in the holding portion corresponding to each rib so as to catch the rib in the direction of expansion when the rib is opened; and a stopper provided in the holding portion on the side surface of each rib. A latch pin is provided to fix the rib in the expanded state by being inserted into the pin hole when the rib is expanded; The deployable offset antenna is composed of a mesh forming a mirror surface of the antenna, and the spring applies rotational force to the rib in a direction opposite to the rotation of the rib in the direction in which the antenna is deployed. A deployable offset antenna characterized in that one end of a wire is attached to each of the ribs for rotating the ribs and expanding the antenna by overcoming the force of the antenna.