JPS58134249A - Toothed belt - Google Patents

Abstract

PURPOSE:To suppress the shift due to travel of belt, by twilling a tooth sail of a toothed belt while inclining the twill line to the opposite side of the inclining direction of a tensile cord against the travelling direction of the belt. CONSTITUTION:A toothed belt 1 is constructed with a tensile cord 3 burried in spiral while inclining against the travelling direction of a belt and a tooth sail 4 formed of twilled cloth. The twill line 4a of said cloth is inclined at the opposite side from the inclining direction of the tensile cord 3 against the travelling direction of the belt.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a toothed belt for meshing power transmission.

Conventionally, in toothed belts having toothed portions, S-twist tensile cords and S-twist tensile cords have been used to reduce deviation in belt running caused by the twist direction (S-twist, Z-twist) of the tensile cord embedded inside. It is well known to alternate with Z-twist tensile cords.

In a toothed belt that is formed in an endless manner, the above-mentioned tensile cord is composed of S-twisted cords and Z-twisted cords that are continuously wound in a spiral shape. The arrangement direction of the tension cord is inclined in the winding direction by the buried interval of /pitch with respect to the running direction (length direction) of the toothed belt. Even if S-twisted cords and Z-twisted cords are arranged alternately to cancel out the deviation caused by the twisting direction, belt running will be affected due to the inclination of the tensile cords. This sometimes causes the belt to shift to one side, causing the side surface of the belt to come into contact with the falling-off prevention flange attached to the pulley, resulting in premature wear and a decrease in durability.

In addition, as a means to prevent the bias caused by the twisting and arrangement direction of the tensile cord, as shown in the Mizusho 5 Gootsu 4t♂ Otsu/No. A technique has been proposed in which the teeth of a toothed belt are formed diagonally so as to generate a thrust force to form a helical belt.

However, in the above-mentioned helical tooth belt, the angle of the tooth changes depending on the thickness of the tensile cord, winding pitch, and belt length, so it is necessary to prepare many types of molds and pulleys with different helical tooth angles. However, there is a problem with the lack of practicality.

In view of this, the present invention provides a toothed belt in which the tooth canvas covering the tooth surface is made of twill weave and the twill line is inclined in the direction opposite to the direction of inclination of the anti-I cord with respect to the belt running direction, The thrust force generated by the contact between the tooth canvas and the pulley is used to reduce the biasing force caused by the inclination of the tensile cord, thereby suppressing the occurrence of bias due to belt running.

Hereinafter, embodiments of the present invention will be explained chronologically.

In the toothed belt 1 shown in FIG. 1, 2 is a rubber structure as an elastic body forming the back portion 1a and tooth portion 1b of the belt 1; 6 is a tensile cord embedded in the rubber structure 2; is a tooth canvas coated on the surface (tooth surface) of the tooth portion 1b.

The comb structure 2 is made of chloroprene rubber (neoprene)
, styrene butadiene rubber, shrimp chlorohydrin rubber,
It is made of polyurethane rubber or the like, and is formed from a known rubber compound suitable for the intended use (application) of the belt.

The above-mentioned tensile cord 3 is a known glass cord, steel wire cord, Kevlar cord, etc. provided in a predetermined cord configuration, and as shown in FIG. The cord 3a and the Z-twisted tensile cord 3b are alternately wound in a spiral shape, and the tensile cord 3 is inclined at a spiral angle β with respect to the belt running direction R.

Further, the tooth canvas 4 is formed of a twill fabric, and as shown in FIG. It is provided so as to be inclined at an angle of α.

The above twill angle α can be adjusted by changing the composition of the woven fabric, i.e., the thickness, denier, and number of twists of the warp and weft;
Adjustments can be made by changing the density, structure, etc., or by changing the cutting direction (arrangement direction) of the twill fabric at a certain angle. In addition, threads made of materials such as tooth canvas 4 (Yotsu nylon, 6 Otsu nylon, Tetron, cotton, rayon, Tefnin-based materials, etc.) or threads made of a blended yarn can be used alone or in combination to provide the required durability as a belt tooth canvas. It is woven to satisfy abrasion resistance and friction coefficient.It is preferable to use woolly canvas using crimped yarn for the stiff and weft yarns.

Due to the striped twill pattern (unevenness) appearing along the twill line 4a on the surface of the tooth canvas 4, when it comes into contact with the Boo IJ surface, it generates a thrust force corresponding to the inclination direction, This thrust force reduces the biasing force generated by the inclination of the tensile cord 3, and the winding angle α is determined by the conditions of the tensile cord 6 (spiral angle β, thickening, twisting configuration, belt length). 100~? depending on the width) and the conditions of the tooth canvas 4 (thread material, thickness, weaving structure, etc.). θ.

It is preferable to set it to .

Next, a method of manufacturing the toothed belt 1 will be explained.

First, a toothed canvas 4 having a desired winding angle α is prepared, and a known adhesive such as RFL, epoxy, incyanate, etc. is applied to this toothed canvas 4 for bonding treatment, and if necessary, rubber glue is applied. etc. are further covered with a wall cloth, and mounted on a mold having an uneven shape corresponding to the toothed portion 1b on the circumferential surface.

At that time, generally, a woolly canvas using crimped yarn as the weft is used as the toothed canvas 4, the width direction of the cloth is the length direction of the belt, the cloth is joined into a cylindrical shape by a known method, and molded into a mold. Attach to. On the other hand, 1. When the woolly canvas is not used, an adhesive-treated toothed canvas 4 is attached along the uneven shape of the mold. When the tooth canvas 4 is worn, the twill line 4a is set in a predetermined inclination direction and at a twill angle α.

The tensile cord 3 is spirally wound around the tooth canvas 4. This tensioned cord 3 has been subjected to an adhesive treatment in advance by a known method. Subsequently, a predetermined rubber compound that constitutes the rubber structure 2 of the back portion 1a and the tooth portion 1b is wrapped.

The belt material constructed as described above is placed in a vulcanizing device, and pressure vulcanization is performed at a predetermined temperature (Ito° C., 30 to Otsu theta minutes). When the vulcanization is completed, the product is taken out from the vulcanizer, the vulcanized product is pulled out from the mold, and the toothed belt 1 is obtained by cutting it into a predetermined belt width.

On the other hand, the results of a shift test conducted by changing the winding angle α of the toothed canvas 4 in the above configuration are shown. In this test, a toothed belt 1
was rotated at a predetermined speed (0θrpm), and the amount of deviation was measured after 5 seconds. In addition, the toothed bell (XL type) used in the experiment has a belt length (circumference) of 30.4'? Be prepared and wide! , 3M, the rubber structure 2 is made of neoprene, the tensile cord 3 is a glass cord with a diameter of O1, and the spiral angle β is 0.
It is 26°.

In addition, the tooth canvas 4 is woven into a 2/2 twill structure using zz nylon threads, and the angle of the twill with respect to the warp and warp yarns is 4tj°.
A test was conducted using the following canvas and the cutting angle of the canvas. The results of the above bias test are shown in the table below.

As is clear from the above table, when the twill angle θ0 is exceeded and the inclination direction of the twill wire 4a becomes the same side as the inclination direction of the tensile cord 6, the amount of deviation becomes very large, and the twill angle α
The tilt of the tensile cord 3 with respect to the belt running direction is 200 or less so that the twill is tilted to the opposite side to the belt running direction, so that an offset suppressing effect can be obtained.
It is large in the range of 00 to ♂o0, and is particularly noticeable in the range of 300 to ♂o0.

As explained above, the toothed belt of the present invention can prevent the deviation of the belt caused by the tensile cord that is buried in a spiral shape and is inclined with respect to the belt running direction, by using the tooth canvas made of twill weave along its twill lines. is inclined in the direction opposite to the direction of inclination of the tensile cord with respect to the belt running direction, and is reduced by the thrust force generated by contact between the tooth canvas and the pulley, thereby suppressing deviation due to belt running. This makes it possible to prevent abnormal wear caused by contact of the side surface of the belt with the flange of the pulley, thereby extending the life of the belt.

In addition, the twill angle of the toothed canvas can be changed simply by changing the direction in which the toothed canvas is arranged, so it can be easily done without preparing many types of molds, etc., and is extremely practical. It is something.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a cross-sectional side view of the main part of a toothed belt, and FIG. 2 is a bottom view of the main part of the toothed belt with the toothed canvas and rubber structure partially removed. It is.

Claims (1)

[Claims] (1) In a toothed belt having a tensile cord embedded in a spiral shape and inclined with respect to the belt running direction, and a toothed canvas coated on the tooth surface, the toothed canvas is composed of a twill fabric, and this A toothed belt characterized in that the twill lines of the twill fabric are inclined in the direction opposite to the direction of inclination of the tensile cord with respect to the belt running direction. (21) The toothed belt according to claim 1, wherein the angle formed by the twill line of the toothed canvas is 100 to ♂θ0 with respect to the belt running direction.