JPS616603A - Method for manufacturing optical fiber sheet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for continuously manufacturing an optical fiber sheet-like body useful as a constituent unit of an image transmission body called an image guide. More specifically, the present invention relates to a method for continuously producing an optical fiber sheet consisting of a large number of optical fibers arranged parallel to each other on the negative plane and fixed to each other by adhesive.

[Technical background]

An image transmission body called an image guide using optical fibers generally has a structure in which the optical fibers are arranged in parallel orderly so that both ends have rectangular end faces, and both ends of each optical fiber correspond to the address of the fiber. This allows an image received at one end to be accurately transmitted to the other end.

To manufacture such an image transmission body, first, a large number of optical fibers are arranged parallel to each other on one surface, and these are adhesively fixed to each other to create the desired number of optical fiber sheets. Generally, a method is used in which these sheet-like bodies are laminated and adhered to each other. Therefore, in order to obtain a good quality image transmission body, it is important to know how to produce a good quality optical fiber sheet. In other words, in order to achieve accurate image transmission, each optical fiber of the optical fiber sheet in the image transmission body must correctly maintain a predetermined position at both ends, and the arrangement density of the optical fibers in the sheet must be adjusted. It is necessary to make it as high as possible. For this purpose, it is necessary to bring the optical fibers in the sheet-like body close to each other at a density (hereinafter referred to as close-packed state density) where the optical fibers are almost in contact with each other.

Conventionally, it has been considered to use a warping machine for weaving in order to manufacture the above-mentioned optical fiber sheet-like body. In this case, a reed is used as a fiber arrangement regulating means, but there is a limit to increasing the arrangement density of the fiber groups, and the
It was not possible to arrange them so close together that they were arranged at a density where they were almost in contact with each other. Also, using conventional fiber convergence means, the fibers cross each other within the fiber group, making it difficult to hold the ends in place.

[Purpose of the invention]

An object of the present invention is to continuously produce an optical fiber sheet-like body in which a group of optical fibers are arranged parallel to each other on one surface and are adhesively fixed to each other at close-packed state density. The goal is to provide a way to do so.

[Structure of the invention]

In order to achieve the above object, the method for continuously producing an optical fiber sheet of the present invention involves arranging a group of optical fibers on one surface at a distance from each other, and bringing the optical fibers and groups close together until they touch each other. In the method of manufacturing an integral sheet-like body by bonding and fixing these to each other with an adhesive, the optical fibers are passed through a positioning guide and a plurality of supply rolls at the stage of arranging them, and after being bonded, the optical fibers are passed through a positioning guide and a plurality of supply rolls. The method is characterized in that the arranged sheet-shaped bodies are passed through take-up rolls in order to take them up, and the supply rolls are spaced apart from each other, and at least one of the supply rolls is a driven roll. .

[Detailed description of the invention]

The optical fiber used in the method of the present invention may be of any kind as long as it is used for image guides, and may be either glass-based or plastic-based optical fiber. However, in terms of processing operability, plastic optical fibers are more suitable for the method of the present invention.

There is no particular limitation on the diameter of the optical fiber, but a diameter of approximately 0.05 to 3 mm is generally used.

The adhesive used in the present invention is applied to the fiber group in a liquid state, and is solidified by drying and, if necessary, curing heating. There are no limitations. Generally, two-component curing adhesives, such as a combination of epoxy resin and polyamine,
Alternatively, fast-curing materials such as a combination of a hydroxyl group-containing oligoester resin and a polyisocyanate are preferred. However, liquid adhesives in which thermoplastic resins are dissolved, emulsified or dispersed in suitable volatile solvents, such as solutions of acrylic resins, polyvinyl acetate, polyurethane resins, or epoxy resins in low-boiling solvents, such as isopropyl alcohol or ethyl acetate, are preferred. Alternatively, an emulsion can also be used.

To carry out the method of the invention, for example, as shown in the drawings, a group of optical fibers (1) are pulled out from a number of creels (not shown) of a yarn feeding stand and are guided through a positioning guide (2). The fibers are arranged K on one side through the fibers, spaced apart from each other (5K so as not to intersect with each other), and the fibers arranged at a distance are passed through the supply rolls (3a) and (3b),
A predetermined tension is applied to this, and then it is fed into an optical fiber alignment unit (4)K. In this aligning unit (4), the fibers in the spaced fiber groups are brought close together until they almost come into contact with each other, and an adhesive is applied.

In this way, they are arranged parallel to each other in almost contact with each other,
The optical fibers, which are adhered to each other by means of an adhesive, form a unitary sheet and then pass through an adhesive assimilator (5), for example a dryer or a heater. The adhesive hardens in this adhesive hardening device (5), and the fibers are firmly adhesively fixed to each other.

The thus formed optical fiber sheet is wound up.

In the method of the present invention, the optimum method is proposed as a result of examining particularly the positioning guide (2), the supply roll, and the take-up row (v), and these will be explained in detail below.

The positioning guide (2) is a ring-shaped thread guide made of ceramic or the like corresponding to the number of optical fibers in a group (1) fixed to a base plate (l) at approximately equal intervals, or a warping guide for textiles. It has a structure that allows a large number of optical fibers to be arranged at approximately equal intervals, like a reed used in machines, etc. Here, the dimensions of the thread guide, the pitch between guides, or the reed dimensions are determined by the thickness of the optical fibers, This should be determined based on the number of fibers and the distance between the positioning guide (2) and the alignment unit (4), but as a guide, the inner diameter of the fiber guide should be large enough to allow the optical fibers (1) to pass through without difficulty. In particular, the pitch between the guides is determined by the angle between the traveling axis direction of the fiber group and the traveling direction of the outermost fibers of the fiber group (hereinafter referred to as The width convergence angle) is preferably in the range of 2 to 10 degrees.

If the width convergence angle is too large, the difference in the length of the traveling path between the fibers placed in the center of the fiber group and the fibers placed on the outside will become large, resulting in the disadvantage that the difference in tension between them will become excessive. arise. Also, if the width convergence angle is too small, disadvantages may occur, such as the fiber groups coming into contact with each other before reaching the width convergence path, or the amount of adhesive penetrating between the fibers being minimal.

The same applies to the case where a reed is used.

The supply roll pulls out the fiber groups spaced apart by the positioning guide (2) and supplies them to the alignment unit (4) under a predetermined tension, and includes at least one driving roll having a predetermined effective width. It is a group of multiple rolls made of metal or rubber.

In general, this type of supply roll is often of the nip roll type, which has a mechanism that allows the object to be supplied (thread, sheet, etc.) to be sandwiched between a pair of rolls and sent out by driving the rolls. In the case of the present invention, as shown in the drawing, a plurality of (two in the drawing) supply rolls (3a) and (3b) are maintained in a positional relationship that does not touch each other, and the fibers are wound in a figure-eight pattern when viewed from the side. At least one of the two attachment rolls, in the drawing the supply roll (3b)
The mechanism is such that a large number of optical fibers (1) are sent out by driving the optical fibers (1).

The take-up roll (6) that takes over the formed optical fiber shifted body (11) is composed of a metal drive roll (8) and a rubber nip roll (9) as shown in the drawing. The sheet-like material (11) is taken up while being sandwiched between both rolls (81, +91). By applying appropriate nip pressure between the rolls, the optical fiber sheet-like material is removed immediately after the sheet has been heated in the previous stage. The shaping effect (11) can be obtained.

The reason why the take-up row /I/+6+ for this take-off is not structured like the supply rolls (3a) and (3b) is that firstly, the fibers pass through the rolls in the form of a sheet. This is because there is no risk of single fibers being crushed as they are when passing through the rolls (3a) and (3b), and secondly, the nip method is better in ensuring that the fibers are taken off at a constant speed.

〔Effect of the invention〕

As is clear from the above description, in the present invention, a positioning guide (2) is provided as an auxiliary means in the first stage of aligning a large number of optical fibers (1) in the alignment unit (4) in a close-packed state, and furthermore, The method is characterized by using two types of supply methods depending on the properties of the material to be supplied, and is extremely effective as a means for making a sheet-like body (11) by aligning a large number of optical fibers (1). .

Further, according to the method of the present invention, the fibers can be sent out without being nipped with rolls, so there is no risk of the fibers being crushed by the nip. Another advantage of this method is that even if a slight difference in tension occurs between a large number of optical fibers, the tension difference can be absorbed by the fibers slipping on the roll surface.

[Brief explanation of the drawing]

The drawing is an explanatory perspective view showing an example of an apparatus for carrying out the method of manufacturing an optical fiber sheet according to the method of the present invention. (1)...Optical fiber (2)...Positioning guide (3a) (3b)...Supply roll (6)...
・Takeover roll

Claims (1)

[Claims] 1. Arranging a group of optical fibers on one surface at a distance from each other, bringing the optical fiber groups close together until they touch each other, and fixing them together with an adhesive to form an integrated sheet-like body. In the manufacturing method, in the step of arranging the optical fibers, a positioning guide and a plurality of supply rolls are passed through, and after adhesion, a take-up roll is passed in order to take up the arranged sheet-like body, and the supply A method for producing an optical fiber sheet, characterized in that the rolls are spaced apart from each other and at least one of the supply rolls is driven.