JPS6333682B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a metal spacer used at the center when a plurality of core wires are collected and arranged as one.

When a plurality of optical fiber core wires for communication are installed in a structure of coaxial cores and parallel pairs, for example, Japanese Patent Application Laid-Open No. 51-67141 and Japanese Utility Model Application No. 52-13851 are recommended for the purpose of reinforcing the communication lines. As disclosed in
A metal spacer is used that has an optical fiber storage groove formed on its outer peripheral surface. Generally, it is desirable for this metal spacer to be as small in diameter as possible and as strong as possible, and conventionally, it is made by the following method.

That is, metal spacers are generally made by passing a solid, soft, aluminum or copper wire having a circular cross section through a deformed die.

However, in this method, the force required to form the metal filament is large, and if heating is used as an auxiliary means to reduce this force, the function of the material will deteriorate. And if you use a metal filament made of hard material,
Because of the forming force, the grooves cannot be made deep, and on the other hand, if a metal filament made of a soft material is used, the tensile strength is low and it tends to tear easily.

Therefore, the present invention relates to a method for manufacturing a metal spacer that eliminates such drawbacks.The structure is such that a tensile strength member is inserted into a metal tube, and a tensile strength member is inserted into the outer circumference of the metal tube from multiple locations at the center of the metal tube. The present invention is characterized in that the metal tube is pressurized so that the metal tube and the tensile strength body are integrated, and a plurality of grooves for storing wire rods are compression-molded on the outer periphery of the metal tube.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for manufacturing a metal spacer according to the present invention will be described in detail below based on an embodiment shown in the drawings.

First, as shown in FIG. 1, a tensile strength member 2 such as stainless steel wire or steel wire is inserted for reinforcement into a circular hollow metal tube 1 made of a soft material such as aluminum or copper. The reason why the hollow metal tube 1 is used is that when compressing the groove 3 on the outside of the metal tube 1 by applying pressure from the outer periphery as described later, the groove 3 can be formed even under a small pressure compared to the case of a solid tube. This is because it is possible. Next, in this embodiment, the outer periphery of the metal tube 1 is divided at four equal intervals, and pressure is applied on a line extending along the axial center of the metal tube 1 from the outer periphery of the metal tube 1 toward the axial center. In this embodiment, four U-shaped grooves 3 are formed on the outside of the tube 1 (see FIG. 2). Furthermore, metal tube 1
Apply pressure from the entire outer periphery of the gap 4 (shown in Figure 2).
A metal spacer like the one shown in FIG. 3 without the metal spacer is obtained. In order to compression mold the entire outer periphery or a portion of the metal tube 1 in this manner, it is possible to perform hydraulic processing using fluid pressure or simply to pass the metal tube 1 through a die array having an irregular cross-sectional shape.

In the manufacturing method described above, if the inner diameter dimension b of the metal tube 1 is sufficiently larger than the outer diameter dimension a of the tensile strength member 2, the force required for forming will be smaller, and it will be easier to manufacture long metal spacers. It is advantageous. Further, the cross-sectional area of the metal tube 1 must be selected so as to be larger than the cross-sectional area of the portion of the metal spacer formed by deformation of the metal tube 1 during final finishing.

As explained above based on the examples shown in the drawings, the manufacturing method for such metal spacers is easy to process and form, and since auxiliary means such as heating are not required, the material does not change and the physical properties is kept constant. In addition, since it can be processed whether the material is hard or soft, metal pipe materials can be selected from a wide range.
It can also be used on hard metal pipes such as iron. Furthermore, since the tensile strength member can be embedded in the center of the metal spacer regardless of the material, the strength of the metal spacer can be sufficiently increased.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the metal spacer before pressure forming with the tensile strength member inserted into the metal tube, Figure 2 is an intermediate pressurized cross-sectional view of the metal spacer with the metal tube partially press-formed, and Figure 3 is the same as that of Figure 2. It is a sectional view of a metal spacer completed by further pressure forming the entire outer periphery of the metal tube. In the drawing, 1 is a metal tube, 2 is a tensile strength member, 3 is a groove,
4 is a gap.

Claims (1)

[Claims] 1. Insert a tensile strength member into a metal tube, apply pressure to the metal tube from multiple locations on the outer periphery toward the center of the metal tube, integrate this metal tube and the tensile strength member, and A method for manufacturing a metal spacer, characterized in that a plurality of grooves for storing wire rods are compression-molded on the outer periphery of a metal tube.