JPH0781606B2 - Toothed belt - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toothed belt in which tooth portions are arranged at a lower portion of the belt at regular intervals and a lower surface of the belt is covered with a woven cloth, and more particularly to a woven cloth used for the toothed belt.

[0002]

2. Description of the Related Art In recent years, toothed belts in which tooth portions are arranged under a belt at regular intervals are being used in various fields, and are subjected to severe conditions such as high speed rotation, high load, and high temperature. It is also used more often below. Therefore, when used under such harsh conditions, deterioration of the material constituting the belt is apt to progress, and the teeth often scatter at an early stage or the core body is cut, often leading to early belt life. It is happening. Therefore, improvement in durability is strongly desired. In addition, with the recent sophistication of automobile and home electric appliances, low noise has been strongly required, and reduction of noise during belt driving has become a serious problem.

Therefore, in order to improve the durability of the toothed belt, for example, as described in Japanese Patent Laid-Open No. 60-81536, a woven cloth having a highly viscous polyamide fiber with a woolly processed yarn is used. Used as a woven fabric for a belt with
For example, as described in JP-A-55-40319, a heat-resistant synthetic fiber having a strength residual ratio of 90% or more after 400 hours have passed one of warp and weft of a woven fabric in an atmosphere at a temperature of 120 ° C. And the other yarn is a synthetic fiber having one of 6 nylon and 6,6 nylon, the one yarn is exposed to the surface of the woven fabric more than the other yarn, and the other yarn is the one yarn. It has been proposed to use a woven fabric that is exposed on the back surface of more woven fabrics as a woven fabric for toothed belts. In order to reduce noise, for example, as described in Japanese Utility Model Laid-Open No. 62-87238, at least one layer of coarse woven fabric is embedded in the belt body, and at least one layer surface is formed on the surface of the belt body. Those made by pasting woven fabrics, for example, Jitsukai Sho 63-1
As described in Japanese Patent Publication No. 1949, as a tooth fabric, there has been proposed a fabric which is subjected only to RFL adhesion treatment and at least a contact surface with the pulley is not rubberized.

[0004]

However, as described above,
Depending on the method, durability can be secured, but low noise performance cannot be secured, and by method, low noise performance can be secured, but durability cannot be secured, durability can be secured. The current situation is that it is not possible to achieve both low noise and ensuring low noise.

The present invention has been made in view of the above points, and an object of the present invention is to provide a toothed belt having improved durability and low noise.

[0006]

SUMMARY OF THE INVENTION The present invention uses spun yarn, which has been rarely used in conventional woven fabrics for toothed belts, as a constituent yarn of the woven fabric, thereby ensuring durability and reducing noise. It is intended to be compatible.

Specifically, it is premised on a toothed belt in which tooth portions are arranged under a belt at regular intervals and the lower surface of the belt is covered with a woven fabric, and the woven fabric is a crimped yarn of synthetic fiber. A weft yarn made of elastic yarn and extending in the belt circumferential direction,
It is characterized in that it is composed of a spun yarn of synthetic fibers and a warp yarn extending in the belt width direction.

[0008]

The nap of the yarn surface of the spun yarn of synthetic fiber exerts a cushioning effect to alleviate the impact received when coming into contact with the pulley when the belt is driven. Therefore, the impact fatigue of the woven fabric is suppressed, and the impact applied to the core body is alleviated. As a result, the service life of the woven fabric and the core body is significantly increased.

Further, this cushioning effect reduces the impact sound generated when the toothed belt meshes with the pulley, and the noise is reduced.

In particular, a spun yarn having a low strength is used as a warp yarn extending in the belt width direction where a load is not applied when the belt is driven, and a stretch yarn made of a crimped yarn of a long fiber yarn as a weft yarn extending in the belt circumferential direction. By using, while maintaining the strength of the conventional woven fabric, it exerts the cushioning effect of the tip.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings.

In FIG. 1 showing a partial cross-section of a toothed belt, 1 is a toothed belt, 2 is the belt body of the toothed belt, and glass fiber, carbon fiber, aromatic polyamide fiber, etc. are provided near the pitch line position. A low-stretch, high-strength core cord 3 made of fibers is embedded in a spiral shape. Reference numeral 4 is a tooth portion formed at a lower portion of the belt body 2 at regular intervals. 5
Is a woven cloth adhered to the lower surface of the belt, the weft yarn 5a extending in the belt longitudinal direction is made of a stretchable yarn which is a crimped yarn of synthetic fiber, and the warp yarn 5b extending in the belt width direction is made of a spun yarn of synthetic fiber. The nap of the yarn surface of the spun yarn of the synthetic fiber exerts a cushioning effect to alleviate the impact received when coming into contact with the pulley when the belt is driven. Nylon fibers, polyester fibers, aromatic polyamide fibers and the like are used as the synthetic fibers.

Then, in order to enhance the cushioning effect, in the woven cloth 5 adhered to the lower surface of the belt, the warp threads 5b made of synthetic fiber spun yarns are weft yarns made of synthetic fiber crimped yarns. It is preferable to have a woven structure exposed on the belt surface as much as possible than 5a. The weave design in which the warp yarns 5b are more exposed than the weft yarns 5a on the belt surface includes, for example, a satin design and an irregular oblique sentence design.

As the rubber constituting the toothed belt, NR
(Natural rubber), SBR (Styrene butadiene rubber), C
R (chloroprene rubber), NBR (nitrile rubber), C
Single or blend of SM (Hypalon rubber), HNBR (hydrogenated nitrile rubber) and urethane elastomer
(Elastic body) or the like is used.

Furthermore, when using such a woven fabric 5,
Adhesive containing a large amount of rubber paste or rubber component (eg RF
By infiltrating L) into the inside of the woven cloth 5, the spun yarn can be appropriately bundled and the defect of wear can be improved without reducing the cushioning effect.

With the above construction, the spun yarn is formed by bundling short fibers differently from the long fiber yarn, and since many naps are present on the yarn surface, the woven fabric 5 covering the lower surface of the belt is formed. In the above, since the spun yarn of the synthetic fiber is used, the raised surface of the spun yarn exerts a cushioning effect to soften the impact received when coming into contact with the pulley when the belt is driven. Since the spun yarn has a lower strength than the continuous fiber yarn, when the belt drives the spun yarn having a low strength, the spun yarn is used as the warp yarn 5b extending in the belt width direction where no load is applied, and the load is applied in the circumferential direction of the belt. Weft 5a extending to
By using an elastic yarn made of a crimped long fiber yarn, the conventional cushioning effect is exerted while maintaining the strength of the conventional woven fabric.

As a result, the impact fatigue of the woven cloth 5 is suppressed and the impact applied to the core cord 3 is also alleviated. As a result, the service life of the woven fabric 5 and the core cord 3 is significantly increased. In addition, this cushioning effect is achieved by the toothed belt 1
Since the impact sound generated when the gear meshes with the pulley is reduced, it is also effective in reducing noise.

Next, Tables 1 and 2 show the structures of the woven fabrics of Examples 1 and 2 of the present invention, Comparative Example and Conventional Example, and Table 2 shows the results of measuring the physical properties thereof.
Shown in.

[0019]

[Table 1]

[0020]

[Table 2]

Then, the woven cloth having the structure shown in Table 1 was treated with rubber glue as is well known, and then used as a woven cloth for covering the lower surface of the toothed belt (see FIG. 1) having the above-mentioned structure. An attached belt was manufactured. That is, the above-mentioned woven fabric is wound around a toothed cylindrical mold, a core cord is spun on it, and an unvulcanized rubber sheet of a certain thickness is further wound around it, and heated from the outside under pressure. With a well-known press-fitting method in which rubber is press-fitted into the tooth groove of the drum, PLD = 0.656 mm
A toothed belt having a belt width W = 19 mm and a belt tooth number Z = 125 was manufactured.

The toothed belt is wound around a driving and driven pulley having 18 teeth with a tension of 20 kg, a load of 4 PS, a rotation speed of 1000 rpm, and an ambient temperature of 100 ° C.
Table 3 shows the results of measuring the time (running time) at the time when the teeth were scattered after running under these conditions.

[0023]

[Table 3]

From Table 3, it can be seen that Examples 1 and 2 of the present invention greatly extend the running time corresponding to the belt life, as compared with the comparative example and the conventional example. In particular, it can be seen that satin weave is superior to twill weave in terms of belt life.

In the same running test, the belt residual stress after running for 100 hours was measured, and the results shown in Table 4 were obtained.

[0026]

[Table 4]

Further, Table 5 shows the measured values of the noise level generated during running in the same running test. The ambient temperature in the noise measurement test was room temperature, and the measured value was 100 rpm.
Fixed at 0 rpm, 300 Hz (primary meshing frequency) and 60
The amount of noise at 0 Hz (secondary meshing frequency) is shown.

[0028]

[Table 5]

From Table 5, it is understood that the invention examples 1 and 2 are not so different from the comparative example, but the noise level is greatly reduced as compared with the conventional example. Further, it can be seen that the twill weave is advantageous over the satin weave in terms of low noise.

[0030]

As described above, according to the present invention, since the warp of the woven cloth for covering the lower surface of the belt is composed of the spun yarn of the synthetic fiber, by raising the yarn surface of the spun yarn of the synthetic fiber,
A cushioning effect is exerted to alleviate the impact received when coming into contact with the pulley when the belt is driven, the impact fatigue of the woven fabric is suppressed, and the impact applied to the core is also alleviated. The life is significantly increased. Further, this cushioning effect reduces the impact sound generated when the toothed belt meshes with the pulley, so that the noise is also reduced.

Therefore, the belt life can be remarkably extended and the noise can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of a toothed belt.

[Explanation of symbols]

 1 Toothed belt 3 Core body cord 4 Tooth portion 5 Woven cloth 5a Weft thread 5b Warp thread

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsutomu Shioyama 3-2-15 Meiwadori, Hyogo-ku, Kobe-shi, Hyogo Bando Kagaku Co., Ltd. (56) Reference JP-A-63-62933 (JP, A)

Claims (1)

[Claims] 1. A toothed belt in which tooth portions are arranged under a belt at regular intervals, and a lower surface of the belt is covered with a woven fabric, wherein the woven fabric is a crimped yarn of synthetic fibers. A toothed belt comprising a weft yarn made of a yarn and extending in the belt circumferential direction, and a warp yarn made of a synthetic fiber spun yarn and extending in the belt width direction.