JPH04331845A - Toothed belt - Google Patents

Abstract

PURPOSE:To improve durability and noise suppressing performance. CONSTITUTION:As for a toothed belt 1, tooth parts 4 are arranged on the undersurface of a belt, keeping certain intervals, and the undersurface of the belt is covered with a woven fabric 5. The woven fabric 5 is constituted of the weft 5a which extends in the belt peripheral direction and consists of the extension/contractible yarn in the form of cimped yarn made of synthetic fiber and the warp 5b which extends in the belt width direction and consists of the spinned yarn of the synthetic fiber. The impact in the contact with a pulley and the impact fatigue applied on the woven fabric 5 are softened by the raising on the yarn surface of the spinned yarn of the warp 5b. Further, also the percussion noise generated in the meshing of the toothed belt 1 with the pulley can be reduced by the raising on the yarn surface of the spinned yarn of the warp 5b.

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 teeth are arranged at regular intervals on the lower part of the belt and the lower surface of the belt is covered with a woven fabric, and particularly to a woven fabric used therein.

0002

[Prior Art] In recent years, toothed belts, in which teeth are arranged at regular intervals on the lower part of the belt, have been used in a wide variety of fields, and are used under harsh conditions such as high-speed rotation, high loads, and high temperatures. It is also increasingly being used below. Therefore, when used under such harsh conditions, the belt's constituent materials tend to deteriorate, causing the teeth to fly off or the core to break, often leading to the end of the belt's lifespan. It is occurring. Therefore, there is a strong desire to improve durability. In addition, as automobiles and home appliances become more sophisticated in recent years, there is a strong demand for low noise, and reducing noise during belt drive has become a major problem.

[0003] Therefore, in order to increase the durability of toothed belts, a woven fabric having Woolly-processed yarns of high viscosity polyamide fibers is used, as described in, for example, Japanese Patent Application Laid-Open No. 60-81536. Those used as woven fabrics for toothed belts,
■For example, as described in Japanese Patent Application Laid-open No. 55-40319, one of the warp and weft of a woven fabric is heat-resistant and has a strength retention rate of 90% or more after 400 hours in an atmosphere at a temperature of 120°C. fiber and the other thread is a synthetic fiber having either 6 nylon or 6,6 nylon, and the one thread is exposed to the surface of the woven fabric more than the other thread, and the other thread is exposed to the surface of the woven fabric more than the other thread. It has been proposed to use a woven fabric in which more of the woven fabric than the threads is exposed on the back side as a woven fabric for toothed belts. In addition, in order to reduce noise, as described in, for example, Japanese Utility Model Application No. 62-87238, at least one layer of coarse fabric is buried in the belt body, and at least one layer of coarse fabric is buried on the surface of the belt body. Those made by pasting textiles on the surface, and
As described in Japanese Patent No. 1949, it has been proposed that a fabric for the teeth uses a canvas that is subjected to only RFL adhesive treatment and that does not rubberize at least the surface that contacts the pulley.

0004

[Problem to be solved by the invention] However, the above-mentioned ■,
Depending on the method (■), it is possible to ensure durability, but it is not possible to ensure low noise, and depending on the methods (■) and (■), it is possible to ensure low noise, but it is not possible to ensure durability, and it is not possible to ensure low noise. The current situation is that it is not possible to simultaneously ensure high performance and low noise.

[0005] The present invention has been made in view of the above points, and an object thereof is to provide a toothed belt having improved durability and excellent low noise properties.

[0006]

[Means for Solving the Problems] The present invention uses spun yarn, which has rarely been used in woven fabrics for toothed belts, as the constituent yarns of the woven fabric, thereby ensuring durability and reducing noise. This is an attempt to achieve both.

Specifically, a toothed belt is assumed in which teeth are arranged at regular intervals in the lower part of the belt, 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 circumferential direction of the belt;
It is characterized by being composed of warp yarns made of spun yarn of synthetic fibers and extending in the width direction of the belt.

[0008]

[Operation] The raised surface of the synthetic fiber spun yarn exerts a cushioning effect that softens the impact received when it comes into contact with the pulley during belt drive. Therefore, the impact fatigue to which the woven fabric is subjected is suppressed, and the impact applied to the core body is also alleviated, and as a result, the life of the woven fabric and the core body is significantly increased.

[0009] Furthermore, this cushioning effect reduces the impact sound generated when the toothed belt meshes with the pulley, thereby reducing noise.

In particular, when the belt is driven, a spun yarn with low strength is used as the warp yarn extending in the belt width direction to which no load is applied, and an elastic yarn consisting of a crimped long fiber yarn is used as the weft yarn extending in the circumferential direction of the belt. By using , it maintains the strength of traditional woven fabrics while still providing the same cushioning effect.

[0011]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIG. 1 showing a partial cross section of a toothed belt, 1 is the toothed belt, 2 is the belt body, and the belt body is made of glass fiber, carbon fiber, aromatic polyamide fiber, etc. near the pitch line position. A low-elongation, high-strength core cord 3 made of fiber is embedded in a spiral shape. 4 is the belt body 2
These are teeth formed at regular intervals on the lower part of the Reference numeral 5 denotes a woven fabric coated and pasted on the lower surface of the belt, in which the weft yarn 5a extending in the longitudinal direction of the belt is made of an elastic yarn which is a crimped yarn of synthetic fiber, and the warp yarn 5b extending in the width direction of the belt is made of a spun yarn of synthetic fiber. . The raised surface of the synthetic fiber spun yarn has a cushioning effect that cushions the impact received when it comes into contact with a pulley during belt drive. As this synthetic fiber, nylon fiber, polyester fiber, aromatic polyamide fiber, etc. are used.

In order to enhance the above-mentioned cushioning effect, in the woven fabric 5 covered and pasted on the lower surface of the belt, the warp yarns 5b made of spun yarns of synthetic fibers are replaced by the weft yarns which are elastic yarns made of crimped yarns of synthetic fibers. It is preferable to have the weave structure exposed on the belt surface as much as possible than 5a. Weaving structures in which the warp yarns 5b are exposed more than the weft yarns 5a on the belt surface include, for example, a satin weave, an irregular diagonal weave, and the like.

[0014] As the rubber constituting the toothed belt, NR
(natural rubber), SBR (styrene butadiene rubber), C
R (chloroprene rubber), NBR (nitrile rubber), C
Single or blends of SM (Hypalon rubber), HNBR (hydrogenated nitrile rubber), and urethane elastomers
(elastic body) etc. are used.

Furthermore, when using such a woven fabric 5,
Rubber glue or adhesives containing a large amount of rubber components (e.g. RFL
) by penetrating into the inside of the woven fabric 5, the spun yarn can be appropriately focused without reducing the cushioning effect,
Wear defects can be improved.

[0016] With the above structure, unlike long fiber yarn, the spun yarn is composed of short fibers bundled together and has many naps on the yarn surface, so that the woven fabric 5 covering the lower surface of the belt By using a synthetic fiber spun yarn, the raised surface of the spun yarn exhibits a cushioning effect that cushions the impact received when it comes into contact with a pulley during belt drive. Note that spun yarn has lower tenacity than long fiber yarn, so when the belt drives a spun yarn with low tenacity, it is used as the warp yarn 5b extending in the belt width direction where no load is applied, and then used as the warp yarn 5b extending in the belt width direction where no load is applied. By using an elastic yarn made of crimped long fiber yarn as the weft yarn 5a extending in the weft, the cushioning effect described above can be achieved while maintaining the strength of a conventional woven fabric.

[0017] As a result, the impact fatigue to which the woven fabric 5 is subjected is suppressed, and the impact applied to the core cord 3 is also alleviated. As a result, the life of the fabric 5 and the core cord 3 is significantly increased. In addition, this cushioning effect is due to the toothed belt 1
Since it reduces the impact sound generated when the pulley meshes with the pulley, it is also effective in reducing noise.

Next, the compositions of the woven fabrics of Examples 1 and 2 of the present invention, comparative examples, and conventional examples are shown in Table 1, and the results of measuring their physical properties are shown in Table 2.
Shown below.

[0019]

[Table 1]

[0020]

[Table 2]

Next, the woven fabric having the structure shown in Table 1 is treated with rubber glue in a well-known manner, and then used as a woven fabric to cover the lower surface of the toothed belt having the above-described structure (see FIG. 1). Manufactured an attached belt. That is, the above-mentioned woven fabric is wrapped around a toothed cylindrical mold, a core cord is spun onto it, an unvulcanized rubber sheet of a certain thickness is wrapped around it, and the material is heated under pressure from the outside. PLD=0.656mm by the well-known press-fitting method of press-fitting rubber into the tooth groove of the drum.
A toothed belt having a belt width W=19 mm and a belt tooth number Z=125 was manufactured.

Then, this toothed belt is wound with a tension of 20 kg between the driving and driven pulleys having 18 teeth.
Load 4PS, rotation speed 1000rpm and ambient temperature 1
Table 3 shows the results of measuring the time (running time) at which the tooth part flew off after running at 00°C.

[0023]

[Table 3]

From Table 3, it can be seen that the running time corresponding to the belt life is significantly longer in Examples 1 and 2 of the present invention than in 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.

Further, in a similar running test, the residual stress of the belt after running for 100 hours was measured, and the results shown in Table 4 were obtained.

[0026]

[Table 4]

Furthermore, Table 5 shows the measured values of the noise level generated during running in a similar running test. The ambient temperature in the noise measurement test was room temperature, and the measured values were taken at a rotation speed of 100.
Fixed at 0 rpm, 300Hz (primary meshing frequency)
and the amount of noise at 600Hz (secondary meshing frequency).

[0028]

[Table 5]

From Table 5, it can be seen that Examples 1 and 2 of the present invention are not significantly different from the comparative example, but the noise level is significantly lower than that of the conventional example. It is also found that twill weave is more advantageous than satin weave in terms of low noise.

[0030]

Effects of the Invention As described above, in the present invention, since the warp of the woven fabric covering the lower surface of the belt is composed of spun yarn of synthetic fiber, the raising of the yarn surface of the spun yarn of synthetic fiber makes it possible to reduce the impact when the belt is driven. - It has a cushioning effect that softens the impact received when it comes into contact with the fabric, suppresses impact fatigue on the fabric, and alleviates the impact on the core, resulting in a significant increase in the lifespan of the fabric and core. do. Further, this cushioning effect reduces the impact sound generated when the toothed belt meshes with the pulley, so noise is also reduced.

[0031] Therefore, the belt life can be significantly increased and noise can be reduced.

[Brief explanation of drawings]

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

[Explanation of symbols]

1 Toothed belt 3 Mind-body code 4 Teeth 5 Woven fabric 5a　Weft 5b Warp

Claims (1)

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