JPS6013942B2 - How to tie yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of tying a thread, and more particularly, to a method of tying a thread so that it does not unravel even if it is pulled before cutting, and the knot easily unravels upon cutting to return to the original thread. .

Glass fibers are widely used as reinforcing materials in reinforced plastics, often in the form of rovings.

A large number of glass monofilaments gathered together is called a glass strand, and roving is a bundle of glass strands that is wound in parallel without twisting. It is usually served as a roll called cheese. When this is cut continuously and used, the rovings must be continuously supplied without interruption, and therefore the cheeses of a large number of rovings must be connected to each other in advance. Usually for this. You need to tie one end of one roving cheese to one end of the next roving cheese. In the normal knotting method, even if the roving is cut, the knot remains as a large number of strands, which causes defects in the reinforced plastic molded product due to the strands. As a method for solving this problem to some extent, a knotting method disclosed in Samurai Ko Sho 49-41494 is known. This method of tying has practical binding strength in terms of the tensile strength of the knotted part before cutting, but the unraveling property after cutting (the degree to which the strands unravel into individual strands, hereinafter referred to as ``unraveling property'') is lower than normal. Although this method is better than the knot method, it is still not satisfactory, and defects caused by insufficient release of the knots between the rovings are increasingly occurring in reinforced plastic molded products. The inventors of the present invention have conducted intensive studies on an excellent way to tie the knot after cutting, which is less likely to cause such defects.
After seeing an improved way to tie roving, he came up with the idea.

In other words, when tying one end of one yarn to one end of another yarn, the front knot in the yarn traveling direction partially divides one yarn into two in front of the end, and the two halves are tied together. One of the threads forms a ring, and within this ring, the remaining thread that has been split into two and another thread intertwine with each other in a criss-cross shape. It consists of tying together in a criss-cross shape and alternating up and down in four places on all four sides around the shape intersection, while the "rear knot" is the thread of the one where the ends of these two types of thread are not divided into two. According to the present invention, the roving comrades are connected in the direction in which the yarn travels, as shown in the roving diagram. Because the radius of curvature of one of the two halves of the ring at the front knot is large, the east-centering property of the yarn is reduced and the accompanying entanglement of the yarn is eliminated, and it is difficult to unravel due to tension before cutting. Therefore, the knotted part is easily scaled by cutting, and the glass strands are well dispersed.

The present invention will be specifically explained below using Examples.

EXAMPLE FIG. 1 shows two glass roving cheese glass strands East 1 consisting of a thickness of 4630 tex (unit of thickness meaning weight in grams per 1000 length) tied according to the invention. This is a model diagram showing the knotted part.

FIG. 2 is a model diagram showing the knotted portion of the glass strand east 1 according to the method disclosed in Japanese Patent Publication No. 49-41494.

Glass strands having a thickness of 4630 tex were tied at 5 points at intervals of one rudder using the tying method of the present invention shown in FIG. 1, and cut into lengths of 25 using an ordinary cutting machine.

As a result of measuring the number of defective blind ends at the connecting part at this time, it was found that no defective opening occurred. Furthermore, the tensile strength of the knotted part was measured using a tensile tester (Autograph manufactured by Shimadzu Corporation, tensile speed 10 ribs/min) and found to be 29k9.
/ It was a knot. Similarly, using the tying method shown in Figure 2, tie the 4630 tex thick glass strand east at 5 female points at 1-skin intervals, and cut it into 2 lengths using a regular cutting machine.
As a result of cutting into 5 ribs, the tensile strength of the knotted portion was further measured under the conditions described above and found to be 22k9/knot. *It was found that the number of East defective items was 6. From the above results, it is clear that according to the tying method of the present invention, the threads are sufficiently loosened after cutting, and the adverse effects on the reinforced plastic molded product due to poor loosening are prevented.

[Brief explanation of drawings]

FIG. 1 is a model diagram showing how to tie the threads of the present invention. FIG. 2 is a model diagram showing the method of tying threads disclosed in Japanese Patent Publication No. 49-41494. Explanation of symbols, 1.
...Glass strand east, 2...The traveling direction of the thread. Bag 1 figure Hair 2 figures

Claims (1)

[Claims] 1. When tying one end of one yarn to one end of another yarn, the front knot in the yarn traveling direction partially divides one yarn into two in front of the end, and the two halves are One of the threads forms a ring, and within this ring, the remaining thread is divided into two, and the other thread intertwines with each other in a cross shape.
Furthermore, this ring is made of a criss-cross pattern that is interlocked alternately up and down at four places on all sides around the cross-shaped intersection, and on the other hand, at the rear knot, the ends of these two types of yarn are divided into two. A method of tying threads characterized by passing through a loop formed by the other thread.