JP2000130514A - Toothed belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and positively restrain a foreign noise from occurring by increasing the damping action of impact force in tooth cloth. SOLUTION: This is a toothed belt 1 consisting of plural tooth parts 2 installed along the longitudinal direction, a back part 4 embedded with cores 3, and a piece of tooth cloth 5 covering each tooth surface 6 and a tooth bottom part 7, and this tooth cloth 5 is made up of comprising a hollow fiber 15 in at least a part of it. Any impact force in time of an engagement between the tooth part 2 of this toothed belt 1 and another tooth part of a pulley is transmitted to a belt body by way of the tooth cloth 5, but if it is transmitted to the hollow fiber 15 used in at least the part of the tooth cloth 5, an internal space plays the role of a damper, and thus the impact force is damped down.

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 surfaces and tooth bottoms are covered with tooth cloth, and more particularly to a toothed belt which can suppress generation of abnormal noise by the tooth cloth.

[0002]

2. Description of the Related Art A toothed belt is composed of a plurality of teeth arranged along a length direction, a back portion in which a cord is buried, and a tooth cloth which covers a tooth surface and a tooth bottom. Toothed belts having a short pitch such as 8.0 mm or 9.525 mm are mainly used in automobiles such as for driving an overhead camshaft.

[0003] In recent years, with the increase in engine output and rotation speed, the operating temperature of the toothed belt has increased and the load on the belt has also increased. High-performance toothed belts corresponding to such required quality are being developed,
In recent years, the demands for abnormal noises have become particularly severe.
Even though the basic performance of the toothed belt is good, there are cases where it is not adopted due to abnormal noise, and the improvement of the abnormal noise is important.

[0004] Usually, the conditions under which abnormal noise is generated are relatively limited. For example, in the case of general industrial use, noise can be improved relatively easily by removing a specific rotational frequency band. . However, in the case of a motor vehicle, a wide range of rotation speeds is used, so that a fundamental solution is required instead of simply removing a specific rotation speed. That is, it is necessary to take measures to suppress the generation of abnormal noise as the toothed belt itself or the belt drive system.

It is considered that the mechanism of generating abnormal noise of the toothed belt is that an impact force when the teeth of the toothed belt and the teeth of the pulley mesh with each other acts as a vibration source, and the belt body vibrates in a string. Therefore, effective measures for eliminating abnormal noise include reducing the impact force. For this purpose, there are a method of reducing the impact force itself and a method of absorbing the impact force. The former is a method of improving the size of the toothed belt and the pulley to improve the meshing state of the toothed belt and the pulley, and the latter is a method of optimizing the material of the toothed belt and the pulley.

[0006]

However, the method of reducing the impact force itself requires many experiments to improve the dimensions of the toothed belt and the pulley and to improve the meshing state of the toothed belt and the pulley. Therefore, there is a problem that time and cost increase. Also, in the method of absorbing the impact force, it is very difficult to design the toothed belt and the pulley so as not to be excessive in quality while maintaining durability, so that time and cost are increased. There was a point.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to improve the effect of damping an impact force on a tooth cloth to easily and surely suppress generation of abnormal noise. It is to provide a toothed belt.

[0008]

According to a first aspect of the present invention, there is provided a method of manufacturing a semiconductor device comprising: a plurality of teeth arranged along a longitudinal direction; a back having a core wire embedded therein; A toothed belt comprising a tooth cloth covering a bottom portion, wherein the tooth cloth is formed so as to include at least a part of a hollow fiber. Hollow fibers for clothing are used to reduce apparent specific gravity and improve heat retention. In the present invention, hollow fibers are used to attenuate the impact force transmitted through synthetic fibers. The impact force when the teeth of the toothed belt mesh with the teeth of the pulley is transmitted to the belt body via the tooth cloth, but when transmitted to the hollow fibers used for at least a part of the tooth cloth, the internal space is reduced. Acts as a damp tray, damping the impact force. Here, the hollow fiber refers to a single filament when the yarn constituting the tooth cloth is composed of multi-filament, and when the yarn constituting the tooth cloth is composed of monofilament, Refers to this monofilament. It is important to have a space in which each fiber is confined as described above, and the impact force transmitted through the hollow fiber is attenuated by the internal space.

According to a second aspect of the present invention, the tooth cloth is formed by weaving a warp in a belt width direction and a weft in a belt length direction, and the hollow fiber is used for all or a part of the warp. The toothed belt according to claim 1. Because of the woven structure of the warp and the weft, the impact force at the time of meshing passes through the warp and the weft. Therefore, hollow fibers are used not for both the warp and the weft, but for the warp which is not easily affected by deformation and abrasion at the time of meshing.

[0010] The invention according to claim 3 is the toothed belt according to claim 1 or 2, wherein the hollow fiber has a hollow ratio of 10 to 40%. The hollow ratio indicates the ratio of the space occupied in the cross-sectional area when the hollow fiber is cut into slices, and is equal to the ratio of air contained in one fiber. If the hollow ratio is less than 10%, the degree of attenuating the impact force is small, and if the hollow ratio exceeds 40%, the hollow fiber is likely to be deformed. A more preferable range of the hollow ratio is 15 to 30%.

According to a fourth aspect of the present invention, the hollow fiber is made of polyamide or polyester and has a thickness of 2
The toothed belt according to any one of claims 1 to 3, which has a denier of 20 to 20 deniers. The strength of the hollow fibers is reduced due to the internal space, instead of the thickness. Therefore, the strength is ensured by selecting a high-strength material and by assembling them finely and densely.
That is, when the yarn is formed by a collection of hollow fibers, there is a space in the space between the fibers in addition to the space inside the fiber. When the thickness of the hollow fiber is reduced, the gap between the fibers becomes smaller, which is offset by the increase in the internal space of the hollow fiber, and the strength of the yarn can be maintained even when the hollow fiber is used.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a structure of a toothed belt, and FIG. 2 is a perspective view showing a structure of a warp which is a collection of hollow fibers.

In FIG. 1, a toothed belt 1 has a plurality of teeth 2 arranged at a predetermined pitch along the longitudinal direction of the belt.
The back 4 in which the cord 3 is embedded, the tooth surface 6 and the root 7
And a tooth cloth 5 that covers the surface of the tooth cloth.

The rubber used for the tooth portion 2 and the back portion 4 has heat aging resistance such as hydrogenated nitrile rubber, chlorosulfonated polyethylene (CSM), alkylated chlorosulfonated polyethylene (ACSM) and chloroprene rubber. Improved rubber is preferred. The hydrogenated nitrile rubber has a hydrogenation rate of 80% or more. In order to exhibit heat resistance and ozone resistance, the hydrogenation rate is 90%.
That's good. A hydrogenated nitrile rubber having a hydrogenation rate of less than 80% has extremely low heat resistance and ozone resistance. In the above rubber, carbon black as a compounding agent,
Zinc white, stearic acid, a plasticizer, an antioxidant and the like are added, and there are sulfur and organic peroxides as vulcanizing agents, but the compounding agents and vulcanizing agents are not particularly limited.

The core wire 3 is obtained by twisting a filament of 5 to 9 μm of E glass or high-strength glass and treating it with an RFL solution or the like, which is a protective agent or an adhesive made of a rubber compound. As an organic fiber, para-aramid fiber having a small elongation under stress and a high tensile strength (trade names: Kevlar, Technora)
A twisted cord obtained by twisting 0.5 to 2.5 denier filaments and treating with an adhesive of an RFL solution, an epoxy solution, an isocyanate solution and a rubber compound is used. The present invention does not limit the core wire 3 to these. The diameter of the core wire 3 is 0.6 to 1.10 m.
Although the range of m is set, if it is less than 0.6 mm, the tensile strength of the core wire 3 is low, and it cannot withstand high load transmission. On the other hand, if it exceeds 1.10 mm, it does not hold in terms of belt dimensions.

The canvas used as the tooth cloth 5 is formed by weaving a warp 11 in a belt width direction and a weft 12 in a belt length direction. The warp 11 is formed by bundling and twisting a number of hollow fibers 15.

As shown in FIG. 2, the hollow fibers 15
It is a filament having an independent space 16 inside.
Such a hollow fiber 15 is obtained by extruding a synthetic resin from a specially shaped spinning nozzle. From the viewpoint of high strength, the material of the synthetic resin is selected from polyamides such as nylon 66 and nylon 6 and polyesters such as PET. One hollow fiber 16 has a relatively small thickness of 2 to 20 denier.

Depending on the cross-sectional shape of the spinning nozzle used, not only the macaroni-like hollow fiber 15 as shown in FIG. 2 but also hollow fibers of various cross-sectional shapes can be obtained. The hollow fiber 21 in FIG. 3A has an overall cross section of a “well” shape, and an independent space 22 having a square cross section is formed in the center. FIG.
The hollow fiber 23 of (b) has a “C” in which the entire cross section is closed.
A closed space 24 is formed at the center, though it can communicate with the outside of the circle. The hollow fiber 25 in FIG. 3C has an overall cross section of “△”, and a plurality of independent spaces 26 are formed. Although any hollow fiber can be used, as shown in FIG. 2, a macaroni-like hollow fiber 21 having a circular cross section and having a space in the center is preferable.

The strength of the hollow fiber 15 is reduced by the amount of the internal space. Therefore, by making the filaments thin, the filaments of the hollow fibers 15 can be densely assembled to form a multi-filament yarn, so that the strength does not decrease even if the yarns have the same cross-sectional area. Specifically, 2 to 20 denier hollow fiber 15 is used. The range that can be used as a multifilament yarn, which is an aggregate of filaments, that is, hollow fibers 15, is 100 to 2000 denier. When the hollow fiber 15 is formed into a multifilament, the yarn is preferably formed with a small number of twists called a sweet twist so that the space 16 inside the hollow fiber 15 is not collapsed.

The space 16 inside the hollow fiber 15 absorbs an impact when the teeth mesh with each other, so that there is a preferable degree of hollowness. The degree of this hollow is the hollow ratio (%)
The ratio is indicated by the ratio of the internal space to the cross-sectional area when the filament is sliced. It is preferable to use hollow fibers 15 having a hollow ratio of 10 to 40%. When the hollow ratio is less than 10%, the degree of absorbing the impact force is small, and the hollow ratio is 4%.
If it exceeds 0%, the single yarn is likely to be deformed. A more preferable range of the hollow ratio is 15 to 30%.

As the weft 12 in the belt length direction, it is preferable to use ordinary synthetic fibers which are not hollow but solid, in order to maintain the abrasion resistance of the canvas. It is selected from monofilaments or multifilaments such as polyamides such as nylon 66 and nylon 6, polyesters such as PET, and aramids. Note that a urethane elastic yarn having elasticity can be used as a part of the weft 12.
Further, the weaving method of the tooth cloth 5 is not limited to the illustrated plain weave,
It may be a satin weave. Although it is possible to form the tooth cloth by knitting, it is preferable to form the cloth from the viewpoint of abrasion resistance.

The above-mentioned tooth cloth 5 is treated with an RFL solution, an isocyanate solution or an epoxy solution, and is adhered so as to cover the tooth surface 6 and the tooth bottom 7.
The RFL solution is obtained by mixing a latex with an initial condensate of resorcinol and formalin, and the latex used here is styrene, butadiene, vinylpyridine three-dimensional copolymer, hydrogenated nitrile rubber, chlorosulfonated polyethylene, Latex such as epichlorohydrin.

As a preferred embodiment, a case has been described in which, out of the warp 11 and the weft 12 of the tooth cloth 5, the warp 11 is formed of a set of hollow fibers 15. However, even when the warp 11 is a mixture of the hollow fiber 15 and the solid fiber, or when the warp is a monofilament yarn and one thick hollow fiber 15 is used, there is an effect of damping the impact force. In addition, tooth cloth 5
Both the warp yarns 11 and the weft yarns 12 may be constituted by multifilaments in which ordinary synthetic fibers and the hollow fibers 15 of the present invention are mixed.

The damping effect when the hollow fiber 15 is used for the tooth cloth 5 as described above will be described. In FIG. 1, when the teeth 2 engage with the teeth of the pulley (not shown), the whole of the teeth 2 is hit by the teeth of the pulley. The impact at the time of this engagement is transmitted to the back part 4 via the tooth cloth 5. Tooth cloth 5
Because of the woven structure of the warp 11 and the weft 12 as shown,
It is transmitted from the warp 11 to the weft 12 or from the weft 12 to the warp 11. As shown in FIG. 2, the warp 11 has a space 1 inside.
6 is an aggregate of hollow fibers 15 having the number 6. When the impact force is transmitted from the hollow fiber 15 to the hollow fiber 15, the space 16 of the hollow fiber 15 acts as a damper to attenuate the impact force. The space 1 between the hollow fibers 15 is included in the warp 11.
7, the impact force is mainly attenuated by the space 16 of the hollow fiber 15. This kind of hollow fiber 15 is used in clothing for weight reduction and heat retention, but has been focused on the fact that it can be used as a damper for attenuating an impact force.

[0025]

The present invention will be described in more detail with reference to the following examples. Examples 1-4, Comparative Example 1 A canvas having the composition shown in Table 1 was subjected to RFL treatment [resorcinol 1
1.0 part by weight, formalin (37%) 8 parts by weight, caustic soda 0.2 parts by weight, styrene, butadiene, vinylpyridine terpolymer (40%) 84.0 parts by weight, chlorsulfonated polyethylene rubber latex (40%) 5
6.0 parts by weight and 121.5 parts by weight of water], dried, heat-treated at 200 ° C. for 3 minutes, and further added with a rubber paste (100 parts by weight of a rubber compound shown in Table 2 and methyl ethyl ketone 680).
Parts by weight, 20 parts by weight of PAPI-135) and air-dried to obtain a tooth cloth.

[0026]

[Table 1]

Next, three ECG 150 glass fibers are aligned as core wires, immersed in the RFL treatment solution, and air-dried.
What was heat-treated at 280 ° C. for 1.5 minutes was separately twisted in the S direction and the Z direction at a rate of 12 times / 10 cm, respectively, to prepare 11 twisted strands. A glass cord in which the cord was twisted in the Z direction and the cord twisted in the Z direction was twisted in the S direction at a rate of 8 times / 10 cm, respectively, was used as the cord. Further, as a material of the back rubber and the tooth rubber, a rubber compound shown in Table 2 was used as a 3.0 mm sheet.

[0028]

[Table 2]

Each tooth cloth shown in Table 1 was finished into an endless cylindrical body, which was set in a mold. From above, a pair of S,
Z-twisted glass core wires are alternately wound spirally at a pitch of 1.3 mm at a winding tension of 10 kg / strand, a rubber sheet of 3.0 mm is stuck thereon, and a vulcanization sleeve is vulcanized by a conventional press-fitting method. After being formed, this was cut into a predetermined width in a ring shape to produce individual belts. The produced belt size is 105S8M19 (number of teeth: 105, belt width: 19.1 mm, tooth pitch: 8 m)
m, belt tooth form: STPD).

In order to measure the sound level of the toothed belt, the sound measuring device shown in FIG. 4 is used. As shown
The toothed belt is driven under the conditions, and the degree of sound pressure is measured by hearing. The results are shown in Table 3.

[0031]

[Table 3]

The degree of audibility is quantified in five stages, and the higher the value, the quieter the sound. A score of 4.0 or more is a pass level. All of the toothed belts using the tooth cloth containing the hollow fibers passed.

[0033]

According to the first aspect of the present invention, at least a part of the tooth cloth is included when an impact force generated when the tooth part of the belt and the tooth part of the pulley engage with each other through the tooth cloth to the belt body. Since the internal space of the hollow fiber attenuates the impact force, abnormal noise of the toothed belt is suppressed.

According to the second aspect of the present invention, since hollow fibers are used for the warp having little effect on the wear resistance and ordinary synthetic fibers are used for the weft having the influence on the wear resistance, the belt tooth portion and The deterioration of the toothed belt can be prevented from abrasion when the teeth of the pulley mesh with each other. Further, since the hollow fiber is less affected by abrasion, it is possible to prevent the attenuation of the impact force from being reduced, and to maintain the effect of suppressing the abnormal noise of the toothed belt.

According to the third aspect of the invention, since the hollow fiber has an appropriate range of the hollow ratio, an effect of suppressing abnormal noise is recognized, and the hollow fiber is hardly deformed at the same time.

According to the fourth aspect of the present invention, since the material and thickness of the hollow fiber are appropriate, it is possible to secure the strength required for the tooth cloth.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the structure of a toothed belt of the present invention.

FIG. 2 is a perspective view showing the structure of a warp using hollow fibers.

FIG. 3 is a view showing another hollow fiber.

FIG. 4 is a schematic view showing a sounding measuring device for a toothed belt.

[Description of Signs] 1 toothed belt 2 toothed portion 3 core wire 4 back 5 tooth cloth 6 toothed surface 7 tooth bottom 11 belt width direction warp yarn 12 belt length direction weft yarn 15 hollow fiber 16 space

Claims (4)

[Claims] 1. A toothed belt comprising: a plurality of teeth arranged along a length direction; a back having a core wire embedded therein; and a tooth cloth covering a tooth surface and a tooth bottom. A toothed belt, wherein the tooth cloth is formed so as to include hollow fibers at least in part. 2. The tooth cloth is formed by weaving a warp in a belt width direction and a weft in a belt length direction, and the hollow fiber is used for all or a part of the warp.
The toothed belt as described. 3. The hollow fiber has a hollow ratio of 10 to 40%.
The toothed belt according to claim 1 or 2, wherein: 4. The toothed belt according to claim 1, wherein the hollow fiber is made of polyamide or polyester, and has a thickness of 2 to 20 denier.