JP2002106642A - Belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure strength of the belt and to improve a fatigue resistance characteristic. SOLUTION: A cord 5 embedded in a belt body has an outer layer 12 made of metallic thin wires and a central part made of a flexible synthetic fiber core 11, and the belt for securing a strength enduring practical use and reducing friction between metal wires, and having a high fatigue resistance characteristic is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a belt used as a conveyor belt or a power transmission belt.

[0002]

2. Description of the Related Art In a conventional toothed conveyor belt, a number of teeth at equal pitches are formed on an inner peripheral surface of a belt body, a tooth cloth is adhered to the inner peripheral surface, and a flat belt of the belt main body is formed. A plurality of cords are embedded in the part in parallel in the belt width direction. For each cord, a strand is created by twisting metal strands, and several strands are further twisted around a metal core wire.

[0003]

By the way, belt strength, flexibility, fatigue resistance and the like are required as the characteristics of the belt.
Although the belt strength is large, when these cords rotate on the pulleys or when they are transported, slip occurs between the strands constituting the cords and friction occurs, and as a result,
There was a problem that the life of the belt was shortened due to breakage of the thin metal wire.

[0004]

Means for Solving the Problems Accordingly, the present inventors have:
As a result of intensive research on the cord structure that improves the fatigue resistance of the above-mentioned belt, when the entire cord is made of synthetic fiber such as nylon fiber, the fatigue resistance is improved compared to the metal wire cord, but the strength is inferior and the actual use is poor. I could not stand it.

[0005] Further, in the case where a structure in which several strands in which a fine metal wire and a synthetic fiber are mixed and twisted are further twisted around a metal core wire or a strand core in which a fine metal wire is twisted is adopted, in terms of strength, it is practically used. Although it was sufficiently durable, as long as the metal core wire (including the strand core) was present at the center of the cord, the fine metal wires slipped and rubbed between the metal core wire and the side strands of the outer layer. It was found that the wire was broken as in the case where the whole was made of a thin metal wire.

On the other hand, in order to avoid friction between the strands, a structure in which a synthetic fiber core such as nylon fiber is disposed at the center of the cord is employed. It has been found that it greatly improves. This is the outer strand side of the cord,
The rubber-like elastic body that forms the belt body enters between the strands, wear does not occur between the strands or the thin metal wires into which the rubber-like elastic body has entered, and nylon fibers, etc. are used in the central part of the cord inscribed in the side strands. It is considered that since the synthetic fiber cores of the above are arranged, they also play a role of reducing the wear between the thin metal wires or the strands.

That is, since the cord outer layer has a sheath-like shape and has a high degree of freedom between the outer layer and the central fiber, the strain applied to the cord when rotating on the pulley is reduced by the center of the cord. It is considered that the burden on the cord is inevitably reduced because the synthetic fiber can be released by the flexibility.

Focusing on the characteristic that the cord core is flexible, besides the above, as the cord core, for example, a non-ferrous metal wire such as a copper wire having a lower hardness than the steel wire constituting the strand is used. The configuration mode can also be exemplified. That is, as an outer layer side strand, a plurality of steel strands are twisted to form one strand,
A plurality of these strands are twisted into the outer layer,
In addition, the core wire at the center of the cord is made of a non-ferrous metal wire such as a copper wire having a lower hardness than the steel wire constituting the strand.

In another embodiment, a core wire at the center of the cord is coated with a flexible rubber or resin coating on a strand made of a non-ferrous metal wire such as steel, fiber core or copper wire. An embodiment can be exemplified. That is, as a side strand of the outer layer, a plurality of steel strands are twisted to form one strand, and a plurality of these strands are twisted to form an outer layer. As a core wire at the center of the cord,
A configuration in which the wire is covered with a flexible rubber or resin coating can be exemplified. In this case, various materials such as a non-ferrous wire such as a steel wire and a copper wire or a synthetic fiber can be applied to the element wire.

As described above, a flat belt, a toothed belt, and the like are used as a belt with a cord in which a flexible cord core is used in the center of the cord and several side strands made of a thin metal wire are twisted on the outer layer. And a ribbed belt can be applied to various belts. Also, for belt applications,
The present invention can be applied to any of transmission belts and transport belts, and can be applied to both endless and endless belts. Further, the material constituting the belt body is applicable regardless of natural rubber, synthetic rubber, or resin elastomer.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of the transport belt of the present embodiment, FIG. 2 is a sectional view of the same transport belt, and FIG. 3 is a sectional view of the same cord.

As shown in the figure, the belt 1 of the present embodiment is
A belt-shaped belt body 2 which is a toothed belt for conveyance,
And a tooth portion 3 formed at an equal pitch in the belt length direction on the inner peripheral surface side thereof; a tooth cloth 4 bonded over the tooth surfaces and the tooth grooves of the tooth portions 3; And a plurality of reinforcing cords 5 buried in parallel in the width direction.

The rubber material forming the belt body 2 and the teeth 3 is made of a thermoplastic urethane elastomer. This thermoplastic polyurethane elastomer is composed of a block copolymer of a flexible segment (flexible segment) and a rigid segment (rigid segment), and its physical properties can be variously changed depending on the application.
As an example, the specific gravity is 1.14, the JISA hardness is 92, the tensile strength is 31 N / mm ² or more, and the 100% modulus is 9.
3N / mm ² , elongation at break 350% or more, tear strength 98
N / mm ² , and the rebound resilience set to 33% or more.

The tooth cloth 4 is bonded to the tooth portion 3 and the tooth groove 6 in order to prevent the belt body 2 and the tooth portion 3 from being worn by contact with a pulley or the like and to maintain their strength. In this case, a synthetic fiber cloth such as 6-6 nylon is used.

As shown in FIG. 3, each reinforcing cord 5 is formed by twisting a fiber core 11 made of a synthetic fiber such as nylon 6 disposed at the center of the cord and a plurality of side strands 12 disposed on the outer layer side. They are finished to have a cord diameter of approximately 1.0 mm. The fiber core 11 is formed by twisting a plurality of (seven) nylon fibers 11a as shown by a region surrounded by a chain line in FIG. Finished with good vibration absorption performance.

The side strands 12 of the outer layer are composed of six strands 12, and each side strand 12 is in the form of a bundle as shown by a region surrounded by a chain line in FIG. Seven 11-mm steel wires 12a are twisted to maintain a predetermined strength. The fiber core 11 and the strand 12 are subjected to a predetermined bonding treatment and twisted.

In the belt having the above-mentioned structure, a thermoplastic elastomer (pellet) is put into an extruder, heated, and extruded as a sheet from an extrusion port. A thermoplastic elastomer molding machine is installed in the vicinity of the extruder, and the tooth cloth 4 is continuously supplied to a rotary mold in the molding machine having a toothed belt as a groove, and the cord 5 is continuously supplied thereon. And furthermore,
The extruded sheet is supplied from above and heated and pressed to impart fluidity to the thermoplastic elastomer, and the fluidity is used to make the tooth cloth 4 follow the mold groove. When the groove of the mold is sufficiently filled with the tooth cloth 4 and the thermoplastic elastomer, the mold is cooled and solidified at its rotational position to form a desired belt. The formed belt is continuously and separately wound up. The formed belt 1 has a structure in which a reinforcing cord 5 is provided inside the belt body 2 and a tooth portion 3 to which a reinforcing tooth cloth 4 is adhered is provided on a tooth surface.

In such a belt 1, since the outer layer portion of the reinforcing cord 5 has a side strand structure made of a thin metal wire, the strength is slightly inferior to that of a steel core (the relative strength is a fiber). Heart: steel core = 100: 110),
The fatigue resistance is greatly improved.

That is, in the side strands 12 of the outer layer of the cord 5, the main rubber (thermoplastic polyurethane elastomer) enters between the strands, and the abrasion is reduced between the strands 12 containing the elastomer or between the thin metal wires 12a constituting the strands. Further, in the central portion of the cord inscribed in the side strand 12, the fiber core 11 such as nylon fiber is disposed, so that the abrasion between the fine metal wires 12a or the strands 12 is reduced, and the outer layer portion and the central portion are also reduced. The degree of freedom between the fiber cores is increased. Therefore, when the belt rotates on the pulley,
The strain applied to the cord can be released by the flexibility of the fiber core 11 at the center of the cord, and the fatigue resistance can be greatly improved as compared with the related art.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that many modifications and changes can be made within the scope of the present invention. For example, in the above embodiment, the description has been given of the transport belt, but the present invention is not limited to this, and the present invention may be applied to a power transmission belt. The present invention is preferably applied to a toothed belt as in the above embodiment, but may be applied to a flat belt.
Further, it goes without saying that the belt can be applied regardless of whether it is endless or endless.

Further, in the above-described embodiment, a configuration in which a plurality of fibers are twisted with respect to the fiber core 11 has been exemplified. Further, the side strands of the outer layer are not limited to a single layer as in the above embodiment,
It may have a multilayer structure. Further, each strand may have a mixed twist configuration of a synthetic fiber such as nylon and a thin metal wire, in addition to a twisted thin metal wire.

Further, as a flexible cord core, a mode composed of a non-ferrous metal wire such as a copper wire having a lower hardness than the steel wire constituting the strand, or a non-ferrous metal wire such as a steel, fiber core or copper wire May be coated with a flexible rubber or resin film.

[0023]

As is clear from the above description, according to the present invention, the cord embedded in the belt body has a flexible core structure at the center of the cord with respect to the outer layer made of a metal wire. It is possible to secure a strength that can withstand actual use, reduce friction between metal wires, and provide a belt having excellent fatigue resistance.

[Brief description of the drawings]

FIG. 1 is a perspective view of a transport belt according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the same conveyance belt.

FIG. 3 is a sectional view of the same cord.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Belt 2 Belt body 3 Tooth part 4 Tooth cloth 5 Reinforcement cord 11 Fiber core 12 Side strand

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kaiki Umehata 172 Ikezawacho, Yamatokoriyama-shi, Nara Prefecture Unita Co., Ltd. Nara Factory F-term (reference) 3B153 AA14 AA33 AA45 BB01 CC22 CC29 CC52 CC55 FF12 GG01 GG03 GG05 GG19

Claims (5)

[Claims] 1. A belt wherein the reinforcing cord embedded in the belt body is constituted by a fiber core at the center of the cord and a plurality of metal side strands twisted around its outer layer. 2. The toothed belt according to claim 1, wherein a tooth portion is formed on an inner peripheral surface side of the belt main body. 3. The belt according to claim 1, wherein said fiber core is made of nylon fiber. 4. A reinforcing cord embedded in a belt body comprises a core wire at the center of the cord and a side strand of an outer layer. The side strand is formed by twisting a plurality of steel strands into one strand. A plurality of these strands are twisted into an outer layer, and the core wire is made of a non-ferrous metal wire such as a copper wire having a lower hardness than a steel wire constituting the strand. 5. A reinforcing cord buried in a belt body comprises a core wire at the center of the cord and a side strand of an outer layer. The side strand is formed by twisting a plurality of steel strands to form one strand. A belt, wherein a plurality of these strands are twisted to form an outer layer, and the core wire is formed by covering a strand of the core wire with a flexible rubber or resin coating.