JPH11166596A - Toothed belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heighten the heat resistance and wear resistance of a toothed belt. SOLUTION: A toothed belt 1 made of rubber is provided with tension members 2 in pitch line positions, teeth 5 formed at constant spaces, and tooth cloth 6 for covering tooth faces. The tooth cloth 6 is composed of knitted material formed of aromatic polyamide fiber, and the large elongation direction of this cloth is oriented in the longitudinal direction of the belt 1. Matrix rubber 3 constituting the belt 1 is fluororubber. The tooth cloth 6 and matrix rubber 3 are connected in the state of part of rubber being filled in the mesh of the tooth cloth 6, and moreover rubber oozes out to the surface so as to heighten the heat resistance and wear resistance of the belt 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a toothed belt using heat-resistant rubber as a matrix rubber.

[0002]

2. Description of the Related Art In toothed belts, it is generally practiced to cover the tooth surface with a tooth cloth to reinforce the tooth surface and prevent chipping and wear. In addition, in order to increase the heat resistance of the toothed belt, a plain woven fabric, a twill woven fabric, a satin woven fabric, or a knitted fabric woven using fibers having high heat resistance such as aromatic polyamide fibers may be used as the tooth cloth. Known (Japanese Utility Model Application Laid-Open No. 58-79157, 58-1)
No. 75246, Japanese Utility Model Laid-Open No. 59-52255, etc.).

However, since the heat-resistant fiber generally has low adhesiveness to the matrix rubber of the belt, it is actually used in combination with a nylon fiber or the like having a high adhesiveness to the matrix rubber. For example, a heat-resistant fiber is used for one of the warp yarn and the weft yarn, a fiber having a high adhesiveness is used for the other, or a fiber in which a heat-resistant fiber and a fiber having a high adhesiveness are mixed is used.

[0004]

However, fibers having good adhesion to matrix rubber, such as the above-mentioned nylon fibers, generally have low heat resistance. There is a problem that the fiber melts. Therefore, even if such fibers are used in combination with the above-mentioned heat-resistant fibers, there is a limit in improving the heat resistance of the toothed belt. Of course, if the tooth cloth is composed only of heat-resistant fibers, the heat resistance should be improved, but the adhesion between the tooth cloth and the matrix rubber is insufficient, and the tooth cloth is easily peeled. , Has not been adopted. This problem of adhesiveness is particularly remarkable when a heat-resistant rubber such as fluorine rubber is used as the matrix rubber.

[0005]

On the other hand, according to the present invention, by increasing the physical bonding force between the tooth cloth and the matrix rubber, the heat resistance rubber is used as the matrix rubber and the tooth cloth is heat-resistant. It can be composed only of conductive fibers.

That is, the invention of this application is directed to a rubber-made rubber having a tension member provided at a pitch line position, teeth formed at a constant pitch on an inner peripheral side, and a tooth cloth covering a tooth surface provided. In the toothed belt, the tooth cloth is made of a plain woven fabric, a twill woven fabric, a satin woven fabric, or a knitted fabric formed of heat-resistant fibers, and a direction in which the elongation of the cloth is increased is oriented in a belt longitudinal direction. The matrix rubber constituting the belt is a heat-resistant rubber, and the tooth cloth and the heat-resistant matrix rubber are characterized in that a part of the rubber is filled in and joined to the eyes of the tooth cloth. Things.

[0007] Therefore, although the above-mentioned tooth cloth is formed of heat-resistant fibers having low adhesion to the heat-resistant matrix rubber, a part of the rubber is filled in the eyes of the tooth cloth, and there is a so-called anchor effect. Works, and the physical bonding force between them is increased, so that the problem of peeling of the tooth cloth is solved. Of course, even if the temperature of the tooth cloth increases due to the use of the toothed belt, the problem of melting can be avoided because the fiber yarns constituting the tooth cloth have heat resistance. Further, since the direction in which the elongation of the tooth cloth increases is oriented in the longitudinal direction of the belt, fatigue deterioration of the tooth cloth is suppressed, the wear resistance is improved, and shear cracking of the teeth is prevented.

In this case, if the matrix rubber filled in the eyes of the tooth cloth is exposed on the surface of the tooth cloth, the anchor effect becomes larger and the coefficient of friction between the tooth cloth and the toothed pulley is increased. Is high, the friction coefficient is reduced by the matrix rubber, so that the belt running noise (the meshing noise between the toothed belt and the toothed pulley) can be reduced.

Further, if the surface of the tooth cloth is covered with a coating made of the same heat-resistant rubber as the matrix rubber, and the rubber coating is integrally bonded to the matrix rubber filled in the eyes of the tooth cloth, The bonding force between the tooth cloth and the matrix rubber is increased, and the friction coefficient is advantageously reduced. Further, since the tooth cloth is protected by the heat-resistant rubber, the heat deterioration can be prevented.

Here, as the heat-resistant fiber constituting the tooth cloth, for example, an aromatic polyamide fiber or a polyparaphenylene benzobisoxazole fiber can be adopted. As the heat-resistant matrix rubber, for example, Fluorine rubber, silicone rubber or the like can be employed.

In particular, it is preferable that the above-mentioned tooth cloth is formed of a knitted fabric of an aromatic polyamide fiber, and that the above-mentioned matrix rubber is a fluorine rubber.

That is, the aromatic polyamide fiber has extremely high heat resistance and abrasion resistance, and the fluororubber has not only high heat resistance but also a high adhesive strength to the tooth cloth as compared with silicone rubber. is there. In addition, the knitted fabric increases the elongation of the tooth cloth and eliminates the need for using a high elongation fiber yarn (that is, a low elongation aromatic polyamide fiber yarn can be used). At the time of manufacturing, when the tooth cloth is superimposed on the tooth mold for molding the tooth surface and the matrix rubber material is pressed through the tooth cloth into the concave part of the tooth mold, the tooth cloth expands and The reason is that the matrix rubber pushes open the stitches of the tooth cloth and is filled well with the stitches at that time, and the matrix rubber is exposed on the tooth cloth surface side.

As the aromatic polyamide, for example, Conex, Nomex, Technora, trade name of Teijin Limited, Kevlar trade name of DuPont, Twaron trade name of Enca, etc. are suitable.

[0014]

Therefore, according to the invention of this application, a plain woven fabric, a twill woven fabric, a satin woven fabric or a knitted fabric formed of heat-resistant fibers is applied to the tooth cloth of the rubber toothed belt, and While the direction in which elongation increases is oriented in the longitudinal direction of the belt, a heat-resistant matrix rubber is applied to the belt, and this tooth cloth and the heat-resistant matrix rubber are partially filled with the rubber into the eyes of the tooth cloth. Because it is a combination of a heat-resistant fiber and a heat-resistant matrix rubber, which have low adhesion to each other, the bonding force between the tooth cloth and the matrix rubber is enhanced by using an anchor effect, and The tooth surface can be reliably reinforced with a highly heat-resistant tooth cloth without causing the problem of peeling or melting of the cloth, the wear resistance on the tooth surface side can be improved, and tooth chipping can be prevented. , The durability of toothed belts has jumped To improve on.

According to the above-mentioned structure, in which the matrix rubber filled in the eyes of the tooth cloth is exposed on the surface of the tooth cloth, it is advantageous in increasing the bonding force between the tooth cloth and the matrix rubber, and the tooth cloth is also improved. It is also advantageous in reducing the friction coefficient between the toothed belt and the toothed pulley to reduce the meshing noise of the toothed belt.

Further, the surface of the tooth cloth is covered with a coating made of the same heat-resistant rubber as the matrix rubber, and the rubber coating is integrally bonded to the matrix rubber filled in the eyes of the tooth cloth. According to the improvement of the bonding force between the tooth cloth and the matrix rubber, reduction of the friction coefficient,
In addition, it is further advantageous in preventing thermal deterioration of the tooth cloth.

According to the above-mentioned tooth cloth formed by knitting an aromatic polyamide fiber and applying fluororubber as the matrix rubber, it is particularly advantageous for improving the heat resistance and wear resistance of the toothed belt. In addition, the manufacture of the toothed belt becomes easy.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the toothed belt 1 shown in FIG. 1, reference numeral 2 denotes a tension member provided at a pitch line position thereof;
Is a matrix rubber of the belt 1. The matrix rubber 3 comprises a back rubber 4 constituting the outer peripheral side of the tensile member 2 and a tooth rubber 5 provided on the inner peripheral side of the tensile member 2 at a constant pitch over the entire circumference. The peripheral tooth surface is covered with a tooth cloth 6, and a thin rubber coating 7 is formed on the surface of the tooth cloth 6.

The tensile member 2 is made of glass fiber, carbon fiber,
The cord is made of a cord having a low elongation and a high strength made of an aromatic polyamide fiber or the like, and is provided spirally so as to extend in the longitudinal direction of the belt and to advance the pitch in the belt width direction. The matrix rubber 3 and the rubber coating 7 are
These rubbers are bonded via rubber filled eyes, and these rubbers are all formed of the same kind of rubber having high heat resistance. Further, the tooth cloth 6 is formed of a knitted fabric knitted with heat-resistant fiber yarn.

The toothed belt 1 can be manufactured by a well-known press-fitting method. That is, a heat-resistant fiber yarn (filament bundle) constituting the knitted fabric is preliminarily impregnated with a rubber component by performing a soaking process in which the knitted fabric for a tooth cloth is immersed in a solution of a rubber-based adhesive. This is for facilitating penetration of the matrix rubber material into the stitches during the rubber molding of the belt.

The thus-processed knitted fabric for a tooth cloth is wound around a cylindrical mold having tooth grooves for forming the teeth of the belt at a constant pitch on the peripheral surface. At this time, the direction in which the degree of elongation of the knitted fabric increases is oriented in the longitudinal direction of the belt (the circumferential direction of the mold). Then, a cord for a tensile member is spirally wound from above, a sheet of unvulcanized rubber (matrix rubber material) is further wound from above, and pressure and heat are applied from outside.

As a result, a part of the unvulcanized rubber is extruded from the gap of the cord for the tensile member toward the tooth space, and the knitted fabric for the tooth cloth is extended along with it and pressed into each tooth space together with a part of the rubber. The unvulcanized rubber is vulcanized to form a matrix rubber. Further, a part of the rubber penetrates into the stitches of the tooth cloth, oozes to the surface of the tooth cloth (mold side), and forms a thin rubber coating on the surface of the tooth cloth.

A plurality of toothed belts 1 can be obtained by releasing the thus obtained belt material from the mold, cutting it into a slice, and inverting it.

<Evaluation of Belt> (Example) As the tooth cloth, Technora T of Teijin Limited was used.
According to 360s (para-aramid) of 20s / 1 (20-count non-twist), 65 W (wells) per 5 cm, C
(Course) knitted (horizontal knitting) so as to be 56 pieces per 5 cm was used. In addition, the direction of C (course) having a large elongation of the knit was oriented in the longitudinal direction of the belt. As the matrix rubber, AFLUS SF781 (fluoro rubber) manufactured by Japan Synthetic Rubber Co., Ltd. was used. A glass cord was used for the tensile member. The method described above was used for manufacturing the toothed belt. This toothed belt has a belt width of 0.5
Inch, belt length is 66 inches H-shaped belt,
Its structure is as shown in FIG.

(Comparative Example 1) A toothed belt was manufactured in the same manner as in the example except that nylon yarn was used in place of the above-mentioned Technora as the fiber yarn constituting the tooth cloth (knitted fabric). In this case, the nylon yarn is 210 de / 1, and W is 5 c
65 lines per m and 60 lines per 5 cm.

Comparative Example 2 A toothed belt was manufactured in the same manner as in Example except that a 2/2 twill fabric was used as the tooth cloth. In this twill fabric, the above-mentioned Technora of 30 s / 1 is used for the warp, and the nylon crimped yarn of 210 d / 2 is used for the weft,
The weaving density was set to 100 per 5 cm for both the vertical and horizontal sides.

Comparative Example 3 A toothed belt was manufactured in the same manner as in Example except that a 2/2 twill fabric was used as the tooth cloth. In this twill fabric, the above-mentioned Technora of 30 s / 1 is used for both the warp and the weft, and the woven density is 1 for 5 cm for both the warp and the weft.
00 pieces.

With respect to each of the toothed belts of the above embodiment and comparative examples 1 to 3, the protruding properties (whether or not the tooth rubber is properly formed) at the time of its production were evaluated, and the driving pulley and the driven pulley were evaluated. (Each of the pulleys was wound around an H-type pulley having 12 teeth), and was run at a belt speed of 20 m / min to evaluate the tooth missing life and noise. Tooth missing life was evaluated by running the belt at an ambient temperature of 140 ° C., and noise was evaluated by running the belt at room temperature.
The magnitude of the noise of each of the other examples was evaluated based on the noise level of the other. The results are shown in Table 1.

[0029]

[Table 1]

According to the table, the embodiment has a tooth missing life of 95.
It was the longest day, the noise was low, and the toothing was good.
It is considered that the noise was reduced because the friction coefficient between the belt and the pulley was reduced by the fluorine rubber covering the tooth cloth surface.

On the other hand, Comparative Example 1 has good tooth protruding properties and low noise, but the heat resistance of the tooth cloth is not obtained due to the use of the nylon thread, and the tooth missing life is shortened. ing. In Comparative Example 2, a nylon crimped yarn was used as the weft yarn to increase the elongation of the twill weave. However, the heat resistance of the weft yarn was low, so that the life of the tooth missing was also shortened. Further, in Comparative Example 2, the elongation of the tooth cloth in the longitudinal direction of the belt is large, which is a standard design, and the seepage of rubber on the tooth cloth surface during belt production is small. However, for this reason, the surface of the tooth cloth cannot be covered with the rubber coating, and in such a conventional method, the friction coefficient between the belt and the pulley increases, and the running noise increases. Comparative Example 3
As in Comparative Example 2, the twill fabric is used for the tooth cloth, but the warp yarn and the weft yarn use technolas with small elongation, so the elongation in the belt longitudinal direction becomes insufficient, and the tooth-extraction property deteriorates. Both chipping life and noise were not good.

[Brief description of the drawings]

FIG. 1 is a partially broken perspective view showing a part of a toothed belt according to an embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Toothed belt 2 Tensile body 3 Matrix rubber 4 Back rubber 5 Tooth rubber 6 Tooth cloth 7 Rubber coating

Claims (4)

[Claims] 1. A tension member is provided at a pitch line position,
In a rubber toothed belt having teeth formed at a constant pitch on an inner peripheral side and a tooth cloth covering a tooth surface, the tooth cloth is a plain fabric or a twill fabric formed of heat-resistant fibers. , The direction in which the elongation of the cloth is large is oriented in the longitudinal direction of the belt, the matrix rubber constituting the belt is heat-resistant rubber, and the tooth cloth and the heat-resistant matrix Rubber is a toothed belt characterized in that a part of the rubber is filled in and joined to the eyes of the tooth cloth. 2. The toothed belt according to claim 1, wherein the matrix rubber filled in the eyes of the tooth cloth is exposed on the surface of the tooth cloth. 3. The toothed belt according to claim 1, wherein the surface of the tooth cloth is covered with a coating made of the same heat-resistant rubber as the matrix rubber, and the rubber coating is formed on the surface of the tooth cloth. A toothed belt, which is integrally connected to a matrix rubber filled in the belt. 4. The toothed belt according to claim 1, wherein the tooth cloth is formed of a knitted fabric of an aromatic polyamide fiber, and the matrix rubber is a fluororubber. A toothed belt characterized by the following.