JPH07208416A - Bar body joint - Google Patents

Abstract

PURPOSE:To make a joint consisting of two bar bodies, whose extended points at the tip cross with a certain angle, light in weight and its manufacturing facilitated by making the cross section shape of a bar body socket in quandrangle and composing the bar body joint with a CFRP layer body. CONSTITUTION:A joint 1, which id a joint to joint two bar bodies 2, holds the bar bodies 2 at their extended points so that they can be cross in an angle theta. The respective bar bodies 2 have their cross sections made in quandrangle and so does the opening cross section shape of the socket of the joint receiving the bar bodies 2. The joint 1, which is laminatedly formed with CFRP (carbon fiber reinforcement plastic), is formed in the manner of using a framework 3, as the base, taking the form of the inside shape of the joint 1 in advance so that the bar body 2 can be inserted therein, and joining it face to face with a prepreg 4 of an identical shape. Since the joint 1 is composed of a combination of rectangules, cut-in places in the prepreg 4 can be made less by taking the form from a cloth material, and the joint 1 is formed by laminating prepreg 4 so as to make it fit the prepregs 4 through sockets, after which the joining parts are join processed and the framework 3 removed. Thus the bar body joint is made light in weight and easily manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a rod-shaped joint suitable for forming a truss.

[0002]

2. Description of the Related Art Conventionally, a joint made of steel or aluminum is often used as a joint for combining rod-shaped bodies such as pipes to form a truss. There are cases where rod-shaped bodies are joined in a straight line to joints and cases where they are joined at a certain angle.In the latter case, in particular, a force is often applied in the angular direction. Manufactured so that the required strength can be obtained by processing or the like.

On the other hand, since aluminum joints are lighter than steel joints, they are used, for example, in forming large trusses for spacecraft. FIG. 3 shows a conventional rod-shaped joint 1, showing a state in which rod-shaped bodies 2 each having a circular cross-section intersecting each other at an angle θ are joined by an opening receiving port 1a.

The aluminum joint 1 is manufactured not by casting but by cutting in order to reduce the weight as much as possible in order to obtain necessary strength. However, manufacturing a joint by cutting from an aluminum block requires a huge number of man-hours for manufacturing because the joint 1 has a complicated shape and configuration in which the joint 1 intersects at an angle θ.

Particularly in the formation of trusses for spacecraft, since a large number of them are required, there has been a demand for facilitating the manufacturing process. Further, since the aluminum joint made by cutting is still heavy in weight, there has been a particular demand for weight reduction.

[0006]

As described above, since the conventional rod-shaped joint is manufactured by cutting from an aluminum block, for example, the joint itself is heavy and requires a lot of manufacturing steps. was there. Therefore, an object of the present invention is to provide a rod-shaped joint which is lightweight and easy to manufacture.

[0007]

According to the present invention, in a rod-shaped joint that joins two rod-shaped bodies in which the extension points of the tip portions intersect each other at an angle, the cross-sectional shape of the receiving port that receives the rod-shaped body is a quadrangle. And is composed of a laminated body of CFRP (carbon fiber reinforced plastic).

[0008]

Since the rod-shaped joint of the present invention is made of a CFRP laminated body, it is possible to reduce the weight, and since the rod-shaped receptacle has a quadrangular cross-sectional shape, the laminated body can be easily laminated. It is a thing.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a rod-shaped joint according to the present invention will be described below in detail with reference to FIGS. FIG. 1 is a perspective view showing an embodiment of a rod-shaped joint according to the present invention.

That is, the rod-shaped joint 1 joins two rod-shaped bodies 2 and is held so that the rod-shaped bodies intersect each other at an angle θ at their extension points. Each rod-shaped body 2 has a quadrangular cross section, and therefore the joint for receiving the rod-shaped body 2 also has a quadrangular cross-sectional shape of the opening.

Therefore, the joint of the present invention having the above-described shape and configuration is formed by laminating with CFRP. A method of forming the laminated body will be described with reference to FIG. FIG. 2 shows a state in which one molding material, that is, a prepreg 4 is fitted into a base of a mold 3 having the inner shape of the joint 1 so that the rod-shaped body 2 is inserted in advance.

Although FIG. 2 shows only one prepreg 4, the shape of the joint 1 is realized by combining and joining the prepregs 4 having the same shape so as to face each other.

The prepreg 4 has the joint 1 itself formed of a rectangular combination, so that it can be formed from a cloth-like material.
The number of cut portions 4a is small, and the strength required as a joint can be maintained. Such prepregs 4 are sequentially laminated so as to be fitted from both receiving ports, the joint portion is subjected to an adhesive process, and then the mold 3 is removed to form a joint.

Here, if the rod-shaped body 2 and the opening of the joint 1 for receiving the rod-shaped body 2 have a circular cross section as in the conventional case, the form 3 has a complicated shape with an angle θ between the receiving ports. In that case, it is necessary to make many complicated notches in the prepreg 4 as well, and a gap is generated in the joint surface, so that sufficient mechanical strength cannot be obtained.

In FIG. 2, the prepreg 4 has been described as being sequentially fitted and laminated along the form 3, but the form 3 is removed in the middle of the lamination, and the prepreg 4 is laminated thereafter by using the laminated body up to that as a base. You may do it.

Since the rod-shaped joint according to the present invention is constructed as described above, the weight can be reduced by 20% and the number of manufacturing steps can be reduced by about 30% as compared with the aluminum machined one. It was Needless to say, in the above embodiment, the rod-shaped body 2 may be in the shape of a pipe having an opening surface of a quadrangle.

[0017]

As described above, the rod-shaped joint according to the present invention is configured so that the receiving port of the rod-shaped body has a rectangular shape.
Further, since it is made of CFRP, it is lightweight and easy to manufacture, and it is used for forming a truss for a spacecraft, for example, and a remarkable effect can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a rod-shaped joint according to the present invention.

FIG. 2 is a perspective view illustrating a method for forming the joint shown in FIG.

FIG. 3 is a perspective view showing a conventional joint.

[Explanation of symbols]

 1 ... Joint. 2 ... Rod-shaped body.

Claims (1)

[Claims] 1. In a joint of a rod-shaped body that joins two rod-shaped bodies in which extension points of the tip end intersect each other at an angle, a cross-sectional shape of a receiving port for receiving the rod-shaped body is quadrangle,
A rod-shaped joint characterized by being composed of a laminated body of FRP.