JPH0319575Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] This invention relates to a telescopic structure that is extended and deployed in outer space and used as a mast for an antenna or the like.

[Conventional technology]

Conventionally, this type of telescopic structure (a telescopic structure that can be used with a mast that can be expanded from a compact folded state to a vertically extended state) was developed by the Special Publication Corporation of 1973-
A technique disclosed in Japanese Patent No. 26653 is known.

[Problem that the invention attempts to solve]

However, in the conventional expandable structure, the horizontal beam device called a small square beam device that connects at least three vertical beams in a lattice column type is a rigid member (with a diameter of about 1 cm) that does not bend due to the torsional force when the structure is folded. Since it is constructed with a rigid structure made of thick small square timbers, not only does the weight of the members of this cross beam device become heavy, but also the diagonal members in each rectangular plane formed by adjacent pivot points of the structure are subjected to only tensile force. It is necessary to use tension members such as wires that can withstand (but cannot withstand compressive forces), and two diagonal tension members are hung in an X shape within each rectangular surface of the structure. It is necessary to make one tension member with a spring and the other tension member without a spring (this is because the cross beam device has a rigid structure, so if the diagonal member is not a tension member as described above, (This is natural for technical reasons as it is not possible to twist and contract the extensible structure in one direction.) Therefore, the following problems arose.

Since the diagonal tension members loosen when the structure is contracted and folded, even if the longitudinal beam device is composed of a continuous flexible rod, the extension force of the structure is due to the winding contraction of the flexible longitudinal beam. The diagonal tension member cannot be used as an elastic member to increase the extension force of the structure without relying solely on the spring force at the time.

If two of the diagonal tension members are stretched in an X-shape within each rectangular plane formed by adjacent pivot points of the structure, the number of diagonal members in the entire structure increases; Many pivot points are concentrated on the pivot device that connects the members, making the structure of each pivot device (joint) complicated and heavy. However, there are problems such as an increase in the weight of the entire structure and an increase in cost.

In conventional structures using diagonal tension members such as those mentioned above, the tension device constantly tensions the extension structure in order to increase the rigidity, so internal stress is constantly generated in each component, especially due to environmental stress. When used in the harsh conditions of outer space, the deterioration of components accelerates and reliability becomes a problem.

[Means for solving problems]

This invention was made in order to solve the above-mentioned conventional problems, and when the structure is extended, the cross-beam devices are separated at intervals in the longitudinal direction of the structure, so that the structure is contracted. The diagonal members are composed of flexible members that are sometimes curved in the vertical direction by torsional force and stretched and overlapped by elastic restoring force; One diagonal member is inserted in a diagonal position in only one direction in the clockwise or counterclockwise direction, and one diagonal member on each side is subjected to tensile force and compressive force in the longitudinal direction of the member. (This diagonal member is elastically curved when the structure is contracted and folded, and has the rigidity to withstand both of the structure's extension forces.) The invention is characterized in that it functions as an elastic member that increases elasticity.

[Example of idea]

Embodiments of this invention will be described below with reference to the drawings. FIG. 1 shows an overall schematic perspective view of the telescoping structure, which is the expanded mast M (this illustrated example shows that there are five stages of cross beam devices 5, which will be described later). The mast M has a lattice structure with a triangular cross section, and has three vertical beams extending in the longitudinal direction. It has a longitudinal beam device 4 composed of beam members 1, 2, and 3. The longitudinal beam members 1 to 3 extend straight in the longitudinal direction of the structure when the mast M (hereinafter referred to as the structure) is extended, but at positions substantially perpendicular to the longitudinal direction of the structure when the structure M is retracted. A continuous flexible member that can be deformed into
It is formed from a bar of FRP (fiber-reinforced plastic such as vinyl ester), and is pivotally connected to a number of cross beam devices 5 and diagonal members 10 at horizontal intervals.

There are, for example, 37 stages of the cross beam devices 5 (the illustrated example in FIG. 1 shows only 5 stages) in the longitudinally extending plane of the structure M, and each of the cross beam devices 5 of each stage has the same structure as the one described above. When the structure M is extended, they are spaced apart in the longitudinal direction of the structure as shown in FIG. In this cross beam device 5 of each stage, the structure M is the sixth
When it is compressed as shown in the figure, it is deformed upwardly or downwardly by the torsional force F as shown by the dotted line in Fig. 6.
When the structure M is completely folded as shown in the lower part of FIG. 6, three flexible members 6, 7, 8 (for example, 2 mm in diameter and long FRP bar with a diameter of about 176 mm) or second
It is composed of a flexible member 9 in the form of an integral radiating arm as shown in the figure, and is connected to the longitudinal beam member 1 through a pivot device 11.
~3.

The diagonal member 10 is a rod-shaped elastic member that is longer than the diameter of the structure (diameter of a circle passing through the longitudinal beam members 1 to 3) and has a rigidity capable of withstanding both tensile force and compressive force in the longitudinal direction of the member. For example, diameter 2mm, length 235
It is made of FRP rods of about mm in diameter, and is located at a diagonal position in one direction with respect to the clockwise direction (counterclockwise direction is also possible) of each rectangular surface formed by the pivot points of the adjacent pivot devices 11 of the structure M. As shown in Figure 1, each one is pivotally connected.

Each pivot device 11 that pivotally connects the diagonal member 10 and the horizontal beam device 5 includes three longitudinal beam members 1 to 3.
Attachment part 1 fixed by an attachment means such as caulking to
2a and adjacent flexible members 6, 7 (7, 8 or 8, 6) of the crossbeam device 5
It has four pivot parts 13a to 13d that pin-support the rod end of the diagonal member 10 and the rod end of the diagonal member 10, as shown in FIGS. Rotating joint 1
3, and the roller shaft 14 protruding outward from the longitudinal beam member mounting portion 12a of the joint shaft 12 has a telescopic guide guided by a spiral guide in a storage cylinder (not shown) of the folding structure. A roller 15 is pivotally supported.

Incidentally, when the cross beam device 5 is composed of an integrated radial arm-shaped flexible member 9 shown in FIG.
The rotary joint 13 has a three-axis joint structure having two pivot parts of the diagonal member 10 and one arm end pivot part of the radial arm-shaped flexible member 9.

Therefore, the telescoping structure of the present invention configured as described above has a telescoping actuating device similar to that of the conventional telescoping structure (this is the same as the device shown in FIG. 8 of the conventional publication, so the explanation will be omitted). Therefore, it expands and contracts in a manner that changes between an extended state in which it is stretched in the vertical direction and a folded state in which it is contracted in the vertical direction. Figure 1 shows the extended state, and Figure 6 shows the folded state. It shows the state in progress.

Here, the effect when the structure M is contracted by the torsional force F in one direction will be explained with reference to FIGS. 6 and 7. When a torsional force F in the clockwise direction in FIG. 6 acts on the structure M, the longitudinal beam members 1 to 3 formed of continuous flexible members will move upward or downward as shown by the dotted line in FIG. The transverse beam device 5 is in an overlapping state in which it is sequentially displaced into a planar shape as shown in FIG. 7, and the diagonal member 10 is curved and displaced as shown in FIG. Folded into an overlapping state.

Figure 7 is based on points a, b, and c in Figure 6,
Points a, a1, a2, b, b1, b2 and c, c1, when the upper part is completely folded,
It is a plan view shown in correspondence with c2, and each point a, b, c, a1, b1, c1, a2, b2,
When the vertical beam members 1 to 3 are completely rolled and contracted, c2 moves on the circumference as shown in FIG. 7, and therefore each of the points a to c (a1 to c1 or a2 to c2)
The triangular transverse beam devices 5, 5', 5'' connecting the structures are displaced as shown in FIG. 7, and each diagonal member 10 (10-1 to 10-1
-6) are elastically curved and overlapped as shown in Fig. 7 so as to overlap at the center and create a space S (forming such a space is effective for inserting a pull-down wire (not shown) of the extension structure M). The bending elastic force of the curved diagonal member 10 is accumulated as an increased extension force when the structure M is extended (an elastic force that assists the extension force due to the winding spring force of the longitudinal beam members 1 to 3).

[Effect of idea]

Since the stretchable structure of this invention is constructed as described above, it has the following effects.

Since the cross beam device 5 is composed of a flexible member that bends vertically due to the torsional force when the structure is folded and expands due to elastic restoring force, the weight of the cross beam device 5 is reduced compared to a conventional cross beam device with a rigid structure. In addition, it is possible to use an elastic member having a rigidity capable of withstanding both tensile force and compressive force for the diagonal member 10.

Since the diagonal member 10 elastically bends when the structure is contracted and folded, this bending force can be used to increase the extension force of the structure.

The diagonal members 10 are inserted one by one in a diagonal position in one direction of each rectangular surface formed by adjacent pivot points of the structure, so that X
Compared to the conventional structure in which two pieces are placed in each mold, the number of diagonal members in the entire structure can be significantly reduced, and the number of pivot points of the pivot device 11 that connects the diagonal members 10 and the cross beam device 5 is also reduced. Since the structure of each pivot device (rotary joint) is simplified and the weight is also reduced, the cross beam device 5 has a flexible structure.
Coupled with the reduction in the weight of the members, it is possible to reduce the weight of the entire structure and reduce costs.

Since the structure of this invention does not have a tension device like the conventional diagonal tension member, there is no problem of internal stress occurring in each component of the extension structure, and therefore it can be used in outer space where the environmental conditions are harsh. Even in such cases, deterioration of members can be kept to a minimum, extending the service life of the structure and improving its reliability.

[Brief explanation of drawings]

Fig. 1 is a schematic perspective view of the extensible structure of this invention in an extended state, Fig. 2 is a perspective view of the main part showing a modification of the cross beam device of the same structure, and Fig. 3 is a partially enlarged view of Fig. 1. The detailed diagram shown in Figure 4 is the same as in Figure 3.
An enlarged cross-sectional view along the line, Figure 5 is - of Figure 4.
A cross-sectional view along the line, FIG. 6 is an action explanatory diagram diagrammatically showing the folded state of the structure (partially folded), and FIG. 7 is a diagram showing the upper part of FIG. 6 to the end. FIG. 3 is a plan view diagrammatically showing a member displacement state and a curved state when completely folded. 1, 2, 3...Longitudinal beam member, 4...Longitudinal beam device, M
... Structure (telescopic mast), 5 ... Cross beam device, 6,
7, 8...Flexible members constituting the cross beam device, 9...
...The same radial arm-shaped flexible member, 10...Diagonal member, 11...Pivot device, 12...Joint shaft,
13...Rotary joint, 13a-13d...Pivot part,
F...Torsional force.

Claims (1)

[Scope of utility model registration request] at least three laterally spaced longitudinal beams that extend straight along the length of the structure when the structure is extended, but are capable of deforming to positions substantially perpendicular to the length of the structure when the structure is retracted; a device;
The structure is located in a plane extending in the longitudinal direction of the structure, and is spaced apart in the longitudinal direction of the structure when the structure is extended, and is moved up and down by torsional force when the structure is retracted. A large number of transverse beam devices constituted by flexible members that are bent and deformed in the direction and stretched and overlapped by elastic restoring force, a pivot device that pivotally connects the transverse beam devices and the longitudinal beam device, and a member length. A clockwise direction of each rectangular surface formed by adjacent pivot points of the structure, which is composed of a rod-shaped elastic member having a length longer than the diameter of the structure and has a rigidity capable of withstanding both tensile force and compressive force in the direction. or a diagonal member that is pivotally connected one by one to diagonal positions in only one direction in the counterclockwise direction, and is characterized by a state in which it is extended in the vertical direction and a state in which it is contracted in the vertical direction. A telescopic structure that can change between folded and folded states.