JPS60205044A - Cord for v-belt - Google Patents

Abstract

PURPOSE:To prevent a cord from damage in its core filament while in the half way of a process the cord for a V-belt is manufactured, by mixing a fiber B, whose melting point is 20 deg.C or more lower than that of a fiber A, with the fiber A in the proportion of 50pts.wt. or less the fiber B to 100pts.wt. the fiber A. CONSTITUTION:This cord, in which a mixed filament is obtained by mixing a low melting point-copolymerized polyester filament of melting point 135 deg.C, 100D/ 10<f> as a fiber B with a polyester filament of melting point 265 deg.C, 1,500D/190<f> as a fiber B after being electrically opened, is manufactured to that of 9,600D by drawing three of the mixed filaments to be twisted together in a direction S into a number of strands 300T/M while two of the mixed filaments to be twisted together in a direction Z reverse to before said twisted direction S into a number of strands 250T/M.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cord for a V-belt, and more particularly, the present invention relates to a cord for a V-belt, for example, a cord for a driving V-belt stretched over a radiator cooling fan of an automobile.
A cord used as the core of a belt-like V-belt,
In particular, the present invention relates to a cord for a V-belt that has excellent convergence, abrasion resistance, and workability.

2. Description of the Related Art One type of V-belt for transmitting driving force for equipment and the like that is used in various fields these days is a V-belt that has a core made of a synthetic fiber cord and laminated rubber on both sides of the core. For example, 1.2.
FIG. 3 is a diagram showing an example of processing a V-belt having a V-belt cord (hereinafter simply referred to as a cord) made of synthetic fiber as a core body, and the processing procedure will be explained in detail as follows. For example, three 1500D/190' polyester filament yarns are mixed and twisted, and then two of these twisted yarns are combined and twisted in the opposite direction to obtain a polyester cord. The cord is dipped in a rubber adhesion improver to adhere the necessary components in the improver (adhesion amount: about 10 parts by weight of solid components), an adhesive film is formed around the polyester cord, and then dried with hot air. death,
This is used as a core for a V-belt. That is, as shown in Fig. 1, a raw rubber sheet (2a) is wrapped around a cylindrical metal doshim D having an appropriate outer diameter selected according to the application of the V-belt, and the adhesive property improvement treatment is applied thereto as described above. Wrap the applied cord 1 in a spiral. Then, another raw rubber sheet 2b is removed from above to form a sheet S, and vulcanization is performed in this state. FIG. 2 shows a state in which the V-belt sheet S which has been vulcanized is cut into a flat plate shape along the cut plane Y shown by the broken line in FIG. Then, the flat sheet s is cut into a cut surface V shown by a dashed line, for example, depending on the purpose of the V-belt.
, by cutting in a direction perpendicular to the incision FJ y while avoiding V2, a plurality of V-belts (2) as shown in FIG. 3 can be obtained. By the way, the cut surfaces V, , V, of the V-belt ■ obtained in this way expose a part of the cord 1, as is clear from FIG. 3, but the adhesive formed on the surface layer of the cord 1 Since the rubber coating originally has low resistance to external forces, if the exposed part of the cord 1 is subjected to strong friction during use, it will wear out and become fluffy, and if this gets worse, it may cause the V-belt v to break (which may lead to shellfish). Therefore, as a method to prevent this, the V-belt v cut as shown in Figure 3 is dipped in a toluene solution or thinner solution of raw rubber prepared separately, and the exposed part of the cord 1 is covered and reinforced. However, in this type of reinforcing process, the aforementioned toluene and thinner are used as solvents for raw rubber.
This method is not preferable in terms of the working environment, and requires the installation of a solvent recovery device, so it cannot be said to be an economically preferable method.

The present invention has been developed in view of the above-mentioned circumstances, and is capable of preventing damage due to fuzzing and abrasion of the core of the cord exposed on the cut surface when the V-belt is cut during processing. The object of the present invention is to provide a functional, easy-to-process, and economical V-belt cord that has good cohesiveness and abrasion resistance without the need for reinforcement such as raw rubber adhesion using solvent processing. It is.

The present invention takes the following 41117 configurations to achieve this object. That is, in order to achieve the above object, the present invention provides a cord for a V-belt, in which fibers (4) 1
The gist of the first invention is that 50 parts by weight or less of the fiber (of a fiber having a melting point lower by 20°C or more) is mixed with 00 parts by weight of the fiber (B), and all or The gist of the second invention is that it is partially molten.

The configuration and effects of the present invention will be explained below in detail based on the drawings showing the embodiments, but the embodiments below are just one specific example, and various designs may be changed in keeping with the spirit of the above and below. Anything that does is included in the present invention.

A thermoplastic synthetic fiber (having a melting point) is used as the fiber (a) constituting the cord of the present invention. For example, melting point 265℃
, 1500D/190f polyester filament yarn and fiber (B) with a melting point of 135°C and 100/10'
Polyester filament yarn with a low melting point of 11% [e.g. "Hot melt adhesive fiber" C JP-A-57-21513
3 mixed filament yarns obtained by electrically opening and mixing [described in issue] and 300 twists in the S direction.
Twist them together at T/M, pull them together and twist them in the Z direction opposite to the above twisting direction with a number of twists of 250. If you twist them at T/M, it will be 9600D.
You will get the code. This cord is composed of 100 parts by weight of polyester filament (9000D) and 6.7 parts by weight (600D) of copolymer polyester filament. Since the fibers are mixed with polyester filament yarn and then twisted, the fibers and the fibers 03) are mixed almost evenly over the entire cross section of the cord. This cord has been subjected to the above-mentioned adhesion improvement treatment prior to processing the V-belt.
After forming an adhesive film around the cord, drying it with hot air for about 30 seconds at a temperature of about 240°C,
The cord of the present invention is used for belt processing, and in the hot air drying step, all or part of the fiber (8), which is a low melting point coweight polyester filament, is melted and fused to the polyester filament of the fiber rotation. There is. Moreover, is the low melting point copolymer polyester filament in the cord? t 1
1. Since they are uniformly mixed together, the cord as a whole is in a state in which the fibers (4) are fused and bundled together using the low melting point copolymer polyester filament as a binder.
There is no chance of loose fluff coming apart due to external forces.

When the cord 1a in this state is processed into a V-belt together with a comb sheet by the method described above and cut according to the purpose, a V-belt (Va) as shown in FIG. 4 is obtained.

At this time, the cut surface Val +Va! Hayaha Shicord 1
a is outputting i.52, but code 1a is as mentioned above (
Since it is focused and bonded with a low melting point resin derived from ia m (Is), even if the cut surface V a Hr V a 2 is subjected to frictional force, it will not easily become fluffed like the conventional code 1. There is no possibility that the function of the V-belt will deteriorate even if the belt is damaged. In addition, reinforcing the cut surface by solvent processing (coating with raw rubber), which was previously considered essential for reinforcing the cut surface, is no longer necessary.There are safety, health and work environment problems caused by solvent processing, and solvent recovery. The economic burden of providing equipment etc. can be eliminated.

In the above example, a cord obtained by mixing fibers (fibers CB and CB) was shown as an example of mixing, but even if the filaments of both fibers are twisted together, they will mix almost as uniformly as mixed fibers. It has been confirmed that the same effect can be obtained even if twisted cords are used instead of mixed fibers. When looking in the longitudinal direction of the cord, fibers (5) and fibers CB are mixed together to the same extent as fibers (5) and fibers (B).
) is preferable.

The following example uses a polyester filament yarn as the fiber (4) in the same manner as in the above-mentioned example, and uses a nylon-6 filament yarn as the fiber (B). That is, constituent fiber (4); polyethylene terephthalate filament yarn 1500D/190f constituent fiber (uniform; nylon-6 filament yarn 105D/
12f was electrically opened and mixed, three mixed filament yarns of both fibers were pulled together to give a 300"7M S twist, and two of these were pulled together and a 250"7M Z twist was applied. Te96
I got the code for 20D. The reason why the directions of the upper twist and the lower twist are reversed is to eliminate torque. The cord is composed of 6.9 parts by weight (620D) of the constituent fibers (4) to 100 parts by weight (9000D) of the constituent fibers (4).

This cord is then subjected to an adhesion improvement treatment. That is, a mixed solution of resorcinol, formalin, and latex is used as the rubber adhesion improver, and the cord is immersed in the mixed solution.
After attaching about 101 latex to the cord, it was heated to 240', which is higher than the melting point of nylon-6 (224~5℃).
It was dried with hot air at C for 30 seconds. As a result, the nylon-6 filaments around the cord were melted, and a cord in which polyethylene terephthalate filaments were bonded together with nylon-6 was obtained. This cord is placed on a raw rubber sheet 2 wrapped around a metal drum D shown in Figure 1.
After winding it into a spiral shape at a density of 0 pieces/inch, and placing a raw rubber sheet 2 on top of it, it was vulcanized by evaporating steam at a temperature of 140°C for 1 hour, and then cut to an appropriate width. It was made into a V-belt. Table 1 shows test results using the V-belt thus obtained as an automobile fan belt. As a comparative example, three pieces of conventional polyethylene terephthalate 1500D/190f were aligned, mixed and twisted, and then two
A 9000D cord obtained by aligning and twisting (the number of twists and twist direction are the same as the cord of the present invention) was subjected to a dipping treatment with the same rubber adhesion improver as the present invention and a hot air drying treatment to form a V-belt. The results obtained using the V-belt obtained in this manner are shown.

[In other words, Table 1 shows the results of running tests when each of the V-belts mentioned above was used as a fan belt for an automobile.The condition of the cut surface of the V-belt was checked every 100,000 km of mileage, and if the shape was good, it was marked as ○ or ○. Check the exposed cord for fuzz or wear.
The damaged state is shown as an ×. According to the test results in Table 1, V-belts using conventional cords already had fluff on the exposed cords after a mileage of 100,000 km, and the cords were damaged at 200,000 km, but when using the cords of the present invention, The V-belt used had no problems at all up to a running pressure of 1'FFL up to 300,000 km, but it was not until the mileage reached 400,000 km that the exposed cord became fuzzed. That is, it is shown that the V-belt obtained using the cord of the present invention can be used without any problem during the period of use of the automobile, even when the mileage t1 of the automobile itself is about 300,000 km.

The fibers (5) used in the cord of the present invention include fibers that have good adhesion to rubber, and t' to plastic synthetic fibers that can improve adhesion to rubber (with a melting point of However, considering the other performance requirements of the V-belt, polyester filaments, nylon filaments, etc. are preferable, and among them, polyester filaments are the most preferable. As for the yarn form, both filament yarn and spun yarn are suitable, but filament yarn is preferable because of its strength. On the other hand, the fiber (B) may be any type as long as it has a melting point 20°C or more lower than that of the fiber (A), but from a practical point of view, the fiber (5
) is preferably not more than 115°C lower than the melting point of For example, it is preferable to use various nylon filaments other than nylon-66, copolymerized polyester filaments, and the like. On the other hand, the amount of fibers (Bl) to be mixed with the fibers or co-twisted is 50 parts by weight or less, preferably 7 to 50 parts by weight, depending on the purpose of the belt and the desired durability. Although it varies depending on the type and combination of
It is 12 parts by weight.

Since the present invention is configured as described above, it is possible to prevent damage due to fuzzing or abrasion of the core of the cord on the cut surface exposed by cutting the V-belt during V-belt processing. It is functional and easy to process with its cohesiveness and abrasion resistance even without reinforcement such as adhesion.
Moreover, an economical code can be provided.

[Brief explanation of the drawing]

1 to 3 are explanatory views of processing examples of a V-belt using a cord as a core, and FIG. 4 is an explanatory view illustrating a V-belt using a V-belt cord according to the present invention. 1.1a...V-belt cord 2a, 2b...Raw rubber sheet D...Metal drum S...Sheet V+Va ''-
V-belt applicant Toyobo Co., Ltd.

Claims (2)

[Claims] (1) V-belt cord, which constitutes the cord (
A cord for a V-belt, characterized in that 100 parts by weight of the cut fiber (A) is mixed with 50 parts by weight or less of a fiber (B) whose melting point is 20° C. or more lower than that of the fiber (A). (2) A cord for a V-belt, in which the fiber (B) whose melting point is 20°C or more lower than that of the fiber (3) is 50 parts by weight or less per 100 parts by weight of the fiber (A) constituting the cord. A cord for a V-belt, characterized in that the fibers (all or part of the fibers) are melted by heat treatment.