JPH0755677B2 - Deployable truss structure - Google Patents

Description

The present invention relates to a lightweight open / close truss structure having high retractability.

[Conventional technology]

In recent years, the performance and reliability of space shuttles, alien rockets, etc. have improved, and an economical merit for space utilization has emerged. In particular, large deployable antennas are indispensable for communication of moving bodies such as ships and vehicles, and deployable truss structure methods that constitute them have been actively developed. On the other hand, in terms of scientific utilization, there is a plan to create a huge space base, and the deployment truss structure as a basic structural method of this base is an important development theme. This is because the deployment structure method is considered to be the most economical in the universe to construct a huge structure.

Fig. 4 shows the above-mentioned expanded truss structure based on the American academic journal "IEEE
TRANSACTIONS ON ANTENNAS AND PROPAGATION "AP-17
It is a diagram showing the conventional deployable truss structure shown in Volume 4 (1969). In the diagram, (1) constitutes the triangular lattice of the upper and lower surfaces of this truss structure, and is bent at the center. Possible bending members, (2) diagonal members supporting the upper and lower triangular lattices,
(3) is a connector for pin-connecting the bending member (1) and the slant member (2).

FIG. 5 is an enlarged view of a portion A surrounded by a broken line circle in FIG. 4, and (4) is a web provided around the connector (3), which includes a bending member (1) and a slant member ( 2) is pin-coupled to the connector (3).

FIG. 6 is an enlarged view of the portion B surrounded by the broken line circle in FIG. 4, showing the details of the central bending portion of the bending member (1), in which (5) is a pin at the central portion. A rotatable hinge lever (6) composed of two plates joined together is attached to one root of the hinge lever (5), and the hinge lever (5) is extended in the direction of unfolding the bending member (1). ) Is a spiral spring, (7) is the bending member (1)
And (7a) and (7b) are pins connecting the hinge lever (5) and the bending member (1), and (7c) is a bending member (1) at the center. It is a connecting pin that is connected at a part.

The above structure has a structure in which a plurality of tetrahedrons each including three bending members (1), three slanting members (2) and three connectors (3) are connected to each other. Also called truss structure. FIG. 7 is a diagram showing a state in which the deployable truss structure is being deployed.

Next, the operation will be described. Initially, the structure constrained by a holding cable (not shown in the retracted shape) becomes movable by cutting the holding cable with a blast tube or the like in response to a command from the ground, and the structure is expanded by the spring force of the spiral spring (6). Get started. The expansion is performed by rotating the hinge lever (5) by the spring force of the spiral spring (6) and rotating the bending member (1) around the connecting pin (7c). By the extension of the bending member (1), the connectors (3) on the upper and lower surfaces spread radially and the expansion progresses. When the bending member (1) extends linearly, the rotational torque generated by the spring force of the hinge lever (5) and the spiral spring (6) and the contact surface pressure on the bending surface of the bending member (1) are The balancing and bending member (1) stops its movement. This is an expanded shape, and the structure is a shape that is connected only by the triangular lattice. The triangular lattice is basically a rigid and stable structure. Conventionally, this kind of structure was very rigid and was considered to be suitable for a deployable antenna or a space station structure.

[Problems to be solved by the invention]

However, in the conventional structure, the connecting points of each member are not concentrated at one point in reality, so that the structure is not flexible enough to hold the shape of oneself. That is, the triangular lattice is rigid only when the connecting condition of each member is connected at one point as shown in FIG. 8, but in the conventional structure, this triangular lattice is many as shown in FIG. Not only does it lack rigidity because it has the hinge connection point, but it also leads to an unstable link structure. 8 and 9, (8) is a basic member constituting a triangular lattice, (9) is a pin joint for connecting the basic member (8), and (3) is a basic member (8) formed by the pin joint (9). ) Is a connector that joins.

As described above, the conventional deployable truss structure using bent members is basically an unstable structure, and thus there is a fatal problem that the deployable antenna or the space base body structure cannot provide the required rigidity. .

The present invention has been made to solve the above problems, and provides a deployable truss structure which is structurally stable and has high rigidity in a shape after deployment.

[Means for solving problems]

The deployable truss structure according to the present invention includes a mandrel having a connector having a pin joint at one end and a mandrel having a stopper at the other end, and a main slide hinge that slides on the mandrel at the time of unfolding and finally comes to rest on the stopper. And four ribs extending in a radial direction with one end pin-connected to the main slide hinge, a synchronous slide hinge sliding between one end of the mandrel and the main slide hinge, and one end radially pin-connected to the synchronous slide hinge. And four coil beams, the other ends of which are pin-coupled to the four ribs, respectively, and a coil spring provided between the main slide hinge and the synchronous slide hinge, and the directions of the mandrels are adjacent to each other. The ribs are arranged so that they are in opposite directions, and the ribs, except the ribs that are the free ends of the expanded truss structure, are A plurality of skeletons formed by connecting diagonally-connected connectors on mandrels that are connected with each other and opposite to each other, between the connectors on the mandrels with the same direction of the mandrel, and the expanded truss structure described above. Between the other ends of the ribs, which are the free ends of the expanded truss structure, and between the other ends of the ribs, which are the free ends of the expanded truss structure, and the above-mentioned connectors. It is attached with a wire to be hung.

[Action]

In the present invention, the wire stretched between the vertices forming the quadrangular pyramid causes a compressive force on the ribs to realize a force equilibrium state. A quadrangular pyramid has a stable structure, which makes it easy to obtain high rigidity.

Furthermore, since each of the above-mentioned quadrangular pyramids deploys in synchronization with each other, the reliability of deployment increases, and the energy from the outside for deploying the quadrangular pyramid by the force of the spring is unnecessary.

〔Example〕

FIG. 1 is a diagram showing an expanded truss structure in an expanded shape showing an embodiment of the present invention. (3a) and (3b) are connectors having pin joints, and (3c) is freedom of the expanded truss structure. A connector (10) provided at the other end of the rib as an end is a mandrel having a connector (3) attached to the tip thereof, and adjacent mandrels are arranged such that their axial directions are opposite to each other. (11) is the mandrel (10)
One end of the main slide hinge (12) sliding above is a pin radially connected to the main slide hinge (11) and is a rib that can be expanded in a direction orthogonal to the axial direction of the mandrel. ) The connector (3a) is opposite to the connector (3a) above, and is pin-coupled to the connector (3b) mounted on the adjacent mandrel (10) in the opposite direction. The ribs, which are the free ends of the expanded truss structure, are connected to the connector (3c).

(13) is between the connectors (3a) attached to the tip of the mandrel (10), (3b), between the connectors (3c) arranged at the free ends of the deployable truss structure, and A wire attached between the peripheral connector (3a) mounted on the mandrel and the connector (3c) arranged at the free end of the deployable truss structure, which is pulled when the deployable truss structure is deployed. It is set so that

(2) is the upper surface side connector (3a) and the lower surface side connector (3a)
Baffle that connects b) and (3c) by pin connection, (14)
Is a synchronous slide hinge that slides on the mandrel between the connector (3) and the main slide hinge (11), and (15) has one end pin-connected to the synchronous slide hinge (14) and the other end rib (12). Shown above is a pin-coupled synchronization beam.

FIG. 2 is an enlarged view of the portion C of FIG. 1, (16) is a stopper that determines the bottom dead center of the main slide hinge (11) during deployment, and (17) is the deployment truss structure of the present invention. Coil spring that gives driving force, θ is mandrel (11) and rib (12)
Shows the angle formed by, and is set to be around 90 ° when deployed.

The unfolding operation of the unfolding truss structure configured as described above will be described below. The deployable truss structure of the present invention is
When stored, a connector on the mandrel (10), for example (3a), a main slide hinge (11) on the mandrel (10), and a rib (12) whose one end is pin-connected to the main slide hinge (11). The triangle with three vertices of another connector, eg (3b), connected to the other end is collapsed, and the rib (1
The angle θ between 2) and the mandrel (10) is zero. The main slide hinge (11) is deployed by the spring force of the coil spring (17).
It is done by pushing the space between and the synchronous slide hinge (14). When the distance between the main slide hinge (11) and the synchronous slide hinge (14) increases, the distance between the connector (3a) on the mandrel (10) and the main slide hinge (11) increases. The distance between the child (3a) and the other connector (3b) is kept constant by the diagonal member (2), and the distance between the other connector (3b) and the main slide hinge (11) is further maintained. Since the ribs (12) are also held by the length of the ribs (12), the triangle consisting of the three vertices expands, and the angle θ formed by the ribs (12) and the mandrel (10) increases. When the angle θ between the rib (12) and the mandrel (10) increases, the other connector (3
The distance between b) and another connector, for example (3c), provided at the other end of another rib (12) whose one end is pin-connected to the main slide hinge (11) also increases. When the main slide hinge (11) comes close to the stopper (16), the upper surface side connectors (3a) are mutually connected, and the lower surface side connectors (3b), (3c).
The wires (13) are stretched between each other and between the connector (3a) at the free end on the upper surface side and the connector (3c) at the free end on the lower surface side. The wire (13) is continuously stretched until the main slide hinge (11) hits the stopper (16).
The stretched wire (13) connects the connector (3) to the rib (12).
Since it is pressed to the side, there is no play in the pin joint, and the deployable truss structure has a high rigidity.

FIG. 3 shows a diagram of the deployable truss structure of the present invention in the process of being deployed.

〔The invention's effect〕

As described above, the present invention has an effect that a high rigidity can be easily obtained because the wire is stretched between the vertices of each quadrangular pyramid and has a structure without backlash.

Further, according to the present invention, since the synchronous beam for synchronizing the expansion and the coil spring for supplying the expansion energy are provided between the rib and the mandrel, the expansion is synchronized, the reliability of the expansion is increased, and the expansion is achieved by itself. effective.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a deployed truss structure showing an embodiment of the present invention, FIG. 2 is a diagram showing a member connecting portion in the embodiment of the present invention, and FIG. 3 is an embodiment of the present invention. FIG. 4 is a diagram showing a shape in the middle of unfolding, FIG. 4 is a diagram showing a shape after unfolding in a conventional example, FIG. 5 is a diagram showing a diagonal member connecting portion in the conventional example, and FIG. 6 is a bent triangular lattice in the conventional example. FIG. 7 is a view showing a mechanism of the bending member, FIG. 7 is a view showing a shape in the middle of development in the conventional example,
The figure shows the physical model of the triangular lattice that was previously considered, 9th
The figure shows an actual physical model of the triangular lattice in the conventional example. In the figure, (1) is a bent member, (2) is a diagonal member,
(3) is a connector, (4) is a web, (5) is a hinge lever, (6) is a spiral spring, (7) is a connecting pin, (8) is a basic member, (9) is a pin joint, (10). Is a mandrel, (1
1) is a main slide hinge, (12) is a rib, (13) is a wire, (14) is a synchronous slide hinge, (15) is a synchronous beam,
(16) is a stopper and (17) is a coil spring. In the drawings, the same reference numerals indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 64-14447 (JP, A) JP 64-14449 (JP, A) JP-B 5-69759 (JP, B2)

Claims (1)

[Claims] 1. A mandrel having a pin joint at one end and a mandrel having a stopper at the other end, a main slide hinge sliding on the mandrel, and one end radially pin-coupled to the main slide hinge. ， Can be deployed in directions orthogonal to the axial direction of the mandrel 4
Ribs, a synchronous slide hinge that slides between one end of the mandrel and the main slide hinge, one end is radially pin-coupled to the synchronous slide hinge, and the other end is the above-mentioned 4
Four ribs, each of which is pin-coupled to a rib, and a coil spring provided between the main slide hinge and the synchronization slide hinge, and the mandrel is arranged so that adjacent ones are in opposite directions. A plurality of skeletons in which ribs other than the free end ribs of the deployed truss structure are connected by connectors of mandrels opposite to each other, and connectors on the mandrels opposite to each other are connected by diagonal members. And between the connectors on the mandrel in which the directions of the mandrels are the same, between the other ends of the ribs that are the free ends of the expanded truss structure, and the other ends of the ribs that are the free ends of the expanded truss structure. And a wire which is provided between the above-mentioned connectors and is stretched between the deployable truss structures when the deployable truss structure is deployed.