JP2002295593A - Toothed belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toothed belt which can prevent the scattering of rubber dust caused by the texture opening of a tooth cloth's weave texture. SOLUTION: A plurality of tooth parts 3 are provided to a belt body 2 embedded with a core wire 1 along in the longitudinal direction, and the toothed belt is formed by covering the surfaces of the tooth parts 3 and tooth bottom parts 4 with the tooth cloth 5. As the tooth cloth 5, warps twisted independently one by one are used and a sailcloth, of which the cloth cover factor is 0.90-0.92 and which is treated with a resorcinol-formalin-latex solution alone, is used. The sailcloth forming the tooth cloth 5 has the small texture opening of the weave texture, and moreover, the texture opening of the weave texture is hard to grow larger despite the wear and tear of the tooth cloth 5 after using the toothed belt for a long period of time. Also, the tooth cloth along the toothed belt in the longitudinal direction is extended more easily, a tooth profile shape can be profiled with excellent accuracy. Furthermore, since the tooth cloth 5 is made into a texture of one third disordered twill weave, the rubber bleeding of the surfaces of the tooth parts 3 is suppressed more than ever and abrasion resistance is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber toothed belt having a transmission surface covered with a fiber material, and more particularly to a small toothed belt having a transmission surface formed of only a fiber material. .

[0002]

2. Description of the Related Art A toothed belt is manufactured by providing a plurality of teeth along a longitudinal direction on a belt body in which a core wire is embedded, and covering a tooth surface and a tooth bottom with a tooth cloth.
The belt body is generally formed of rubber such as chloroprene rubber and hydrogenated nitrile rubber.
A canvas woven using 6 nylon or 66 nylon crimped into a weft along the longitudinal direction of the belt body, and non-crimped 6 nylon or 66 nylon having the same composition as the warp in the width direction of the belt body. Is used.

In order to firmly adhere to the teeth, the canvas is made of resorcinol-formalin-latex liquid (RFL).
Liquid), and it is common to use a tooth cloth formed by rubberization by further soaking or spreading treatment.
Since the coefficient of friction with the toothed pulley becomes high, there is a problem that noise is generated due to friction and powder of rubber covering the tooth cloth is scattered.

[0004] As described in Japanese Patent Publication No. 5-33800, a toothed belt manufactured by using a tooth cloth which does not rubberize at least the contact surface with the toothed pulley is obtained by bonding a canvas with only an RFL solution. , Provided by the present applicant.

[0005]

SUMMARY OF THE INVENTION
Even if the toothed belt provided in Japanese Patent No. 33800 is used for a long period of time, the weave and the warp constituting the tooth cloth have large mesh openings due to wear of the tooth cloth. The rubber of the main body could be exposed. Especially for small toothed belts, it is necessary to reduce the rigidity of the tooth cloth in order to use with a small pulley diameter, and in order to obtain a small tooth shape, only a thin tooth cloth can be used. However, the opening of the texture of the tooth cloth was likely to be large.

When the weave of the weave becomes large and the rubber of the belt body is exposed, the exposed rubber wears between the pulley and the toothed pulley and scatters as rubber powder. . 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 that can prevent scattering of rubber powder due to mesh openings of a tooth cloth. Things.

[0007]

According to the present invention, a plurality of teeth 3 are provided along a longitudinal direction on a belt body 2 in which a core wire 1 is embedded, and the surface of the teeth 3 and a tooth bottom 4 are covered with a tooth cloth 5. In the toothed belt formed as described above, the cloth 5 has a cross cover factor of 0.90 to 0.92, and a canvas treated only with a resorcinol-formalin-latex liquid is used. Things.

The invention according to claim 2 is characterized in that, when the warp yarns of the above-mentioned canvas form the tooth cloth of the toothed belt, they extend along the width direction of the toothed belt. Further, the invention according to claim 3 is characterized in that the resorcin-formalin-latex liquid having a solid content of 30 to 50% by mass is used as the tooth cloth 5.

According to a fourth aspect of the present invention, the density of the warp yarns of the tooth cloth is higher than the density of the weft yarns, and the weaving structure is such that the exposed amount of the twisted yarns extending in the belt width direction and the twisted yarns extending in the belt longitudinal direction is the same The canvas surface, which has a 1/3 random twill weave differently on both sides and has a large amount of twisted yarn extending in the belt width direction, is outward, and the canvas surface having a large amount of twisted yarn extending in the belt longitudinal direction is a tooth rubber layer. The toothed belt according to any one of claims 1 to 3, wherein the belt is positioned on each side.

According to the fourth aspect of the present invention, the density of the warp yarn of the tooth cloth is higher than the density of the weft yarn, and the weaving structure of the twisted yarn extending in the belt width direction and the twisted yarn extending in the belt longitudinal direction. 1 / so that the amount of exposure is different on both sides of the canvas
The canvas surface, which has a three-layer twill structure and has a large amount of twist yarn extending in the belt width direction, is located on the outside, and the canvas surface having a large amount of twist yarn extending in the belt longitudinal direction is located on the tooth rubber layer side. The toothed belt according to any one of claims 1 to 3, wherein a large number of warp yarns having a higher density are exposed on the side in contact with the pulley, and a weft yarn having a lower density than the warp yarns is provided on the back side of the tooth cloth (tooth rubber Layer), the adhesion to the tooth rubber layer and the impregnation of the treatment liquid are improved, and the abrasion resistance is improved, and at the same time the composite properties of the tooth cloth and the tooth rubber layer are improved. As a result, it is possible to prevent the rubber from dropping due to the interference with the pulley and the peeling phenomenon between the tooth cloth and the tooth rubber layer.

According to a fifth aspect of the present invention, there is provided the toothed belt according to the fourth aspect, wherein the density of the warp yarn of the tooth cloth is substantially three times the density of the weft yarn.

According to the fifth aspect of the present invention, since the density of the warp yarn of the tooth cloth is approximately three times the density of the weft yarn, the effect of making the weave structure a 1/3 random twill weave is further clarified. Become.

[0013]

Embodiments of the present invention will be described below. FIG. 1 shows a structure of a toothed belt, in which a plurality of teeth 3 are integrally provided on one surface of a belt body 2 in which a core wire 1 is embedded along the longitudinal direction thereof. It is formed by attaching a tooth cloth 5 to the tooth bottom 4 between the parts 3.

The core 1 is made of polyester, aliphatic polyamide, aromatic polyamide, rayon, glass fiber,
A low elongation high strength material such as a steel wire can be used. A belt body 2 and a tooth portion 3 in which the core wire 1 is embedded.
Is formed as a rubber layer.
(Natural rubber), SBR (styrene-butadiene rubber),
CR (chloroprene rubber), NBR (nitrile rubber),
It can be formed by using a rubber selected from IIR (butyl rubber) alone or by blending it, or can be formed by using a polyurethane rubber in addition to these rubbers.

The tooth cloth 5 may be a cloth obtained by bonding a canvas with only a resorcinol-formalin-latex liquid (RFL liquid). The contact surface with the pulley has an exposed RFL bonding surface. In the present invention, as the canvas forming the tooth cloth 5, a warp yarn independently twisted one by one and having a cross cover factor of 0.90 to 0.92 is used.

Here, the cross cover factor of the canvas is a coefficient indicating how small the gap between the yarns in the canvas, that is, how much the canvas is covered with the yarn. The larger the value, the smaller the gap between the yarns in the canvas. The cross cover factor is defined as calculated by the following equation.

The warp (warp) cover factor K ₁ = d
₁ × n ₁ = k ₁ × n ₁ × √D ₁ Cover factor of weft (weft) K ₂ = d ₂ × n ₂ = k
₁ × n ₁ × √D ₁ Cross cover factor K = K ₁ + K ₂ −K ₁ × K ₂ d ₁ : diameter of warp (cm) n ₁ : yarn density of warp (book / cm) k ₁ : 2 / √ (900000 × π × ρ ₁ ) [ρ ₁ : Specific gravity of warp] D ₁ : Denier number of warp d ₂ : Diameter of weft (cm) n ₂ : Yarn density of yarn (book / cm) k ₂ : 2 / √ (900000 × π × ρ ₂ ) [ρ ₂ : Specific gravity of weft] D ₂ : Denier number of weft The cross cover factor of the canvas forming the tooth cloth 5 is 0.
If it is less than 90, the rubber may ooze out of the tooth cloth 5 when forming the toothed belt, and if the tooth cloth 5 is worn out by using the toothed belt for a long time, the texture of the tooth cloth 5 may be reduced. There is a possibility that the opening of the rubber becomes large and the rubber is exposed. Further, the cross cover factor of the canvas forming the tooth cloth 5 is 0.
If it exceeds 92, the rigidity of the tooth cloth 5 is increased, and it is difficult to accurately adhere the tooth cloth 5 along the shape of the tooth portion 3. Furthermore, by using warp yarns that are independently twisted one by one as the cloth for the tooth cloth, when the average yarn density is the same, compared with the case where two yarns are twisted together and twisted, There is no variation in the gap, and even the largest gap between the yarns is small, and the rubber bleeding on the toothed belt surface is smaller when twisted one by one independently.

[0018] Further, in the case where the two wires are aligned and twisted,
When the rubber flows to the tooth side and pushes the canvas to the tooth surface to form the tooth shape, the tooth shape is formed by the weft extending along the belt longitudinal direction in the canvas. At this time,
If two warp yarns along the belt width direction are aligned to form a canvas, the two warp yarns are aligned at the intersection of the warp yarns and the weft yarns. This limits the weft elongation. On the other hand, one warp
In the case where the canvas is formed by independently twisting each book, even if the yarn density in the canvas is the same as that in the case where the two yarns are aligned,
At the intersection with the weft yarn, the force for suppressing the elongation of the weft yarn is reduced, and the weft yarn elongates and does not hinder the formation of a tooth profile, and the shape of the teeth is easily produced. Further, since the tooth cloth forms a tooth shape by elongation in the belt longitudinal direction, it is effective to use yarns independently twisted one by one on the warp yarns along the belt width direction.

Further, in order to make it difficult for the weave of the woven cloth of the tooth cloth 5 to become large, it is preferable to use a canvas having a high amount of RFL liquid attached thereto. If the amount of the solid content resin of the RFL is high, the surface of the tooth cloth 5 is covered with the resin, the elongation of the tooth cloth 5 is reduced, and the aperture is hardly increased. In order to increase the solid content of the RFL solution, it is preferable to treat the canvas twice with the RFL solution. And in this invention, it is preferable that the solid content adhesion amount of RFL liquid of the canvas which forms the tooth cloth 5 is the range of 30-50 mass%. If the solid content is less than 30% by mass, the effect of reducing the elongation of the tooth cloth 5 and making the aperture less likely to be insufficient becomes insufficient. Conversely, if the solid content exceeds 50% by mass, Since the rigidity of the tooth cloth 5 is increased, it is difficult to accurately attach the tooth cloth 5 along the shape of the tooth part 3, and the size of the tooth part 3 varies. It may decrease. As described above, the warp yarns independently twisted one by one having a cross cover factor of 0.90 to 0.92 are used in a direction along the width direction of the toothed belt, and the RFL is used.
The use of the tooth cloth 5 made of canvas having a solid content of the liquid of 30 to 50% by mass prevents the scattering of rubber powder due to the mesh opening of the tooth cloth, and further prevents the tooth shape. This makes it possible to produce a toothed belt with high precision.

Further, the density of the warp yarn of the tooth cloth is higher than the density of the weft yarn, and the weaving structure is such that the exposed amount of the twist yarn extending in the belt width direction and the twist yarn extending in the belt longitudinal direction are different on both sides of the canvas. It is composed of 1/3 random twill weave,
The canvas surface with a large amount of twist yarn extending in the belt width direction is located on the outside, and the canvas surface with a large amount of twist yarn extending in the belt longitudinal direction is located on the tooth rubber layer side.

The woven structure is as shown in FIG. That is, in FIG. 2, 6 nylon fiber yarns extending in the belt width direction are woven as warp yarns, and 6 nylon fiber yarns extending in the belt longitudinal direction are woven as weft yarns. In FIG. This indicates that the thread (yarn) is exposed on the front side of the tooth cloth 5 and the weft (6 nylon fiber) is exposed on the back side of the tooth cloth 5. On the front side of the 1/3 random twill weave cloth 5, the exposed amount of the warp is larger than that of the weft, and conversely, on the back side, the exposed amount of the weft is larger than that of the warp. The tooth cloth 5 has a canvas surface with a large amount of warp exposed on the outside and a canvas surface with a large amount of weft exposed on the tooth rubber layer side, and has a 2/2 twill tooth shown in FIG. Compared to the cloth, the warp (6 nylon fibers) is more exposed on the front side of the tooth cloth 5, that is, on the side that comes into contact with the pulley, and is longer exposed at a random pitch. Therefore, a large amount of weft (6 nylon fiber yarn) is exposed on the back side of the tooth cloth, that is, on the side in contact with the tooth rubber layer 3,
Moreover, it is exposed at a random pitch for a long time.

In the tooth cloth 5, by setting the density of the warp to be higher than the density of the weft, and more preferably to approximately three times the density of the warp, many warps are exposed on the side in contact with the pulley and further exposed. Since the warp has a high density, it has an effect on the abrasion resistance of the belt while suppressing the seepage of the rubber onto the surface of the tooth cloth. On the other hand, on the side that contacts the tooth rubber layer 3,
Since the weft is exposed, the density of the weft is made smaller than that of the warp, so that the adhesion to the tooth rubber layer and the impregnation of the treatment liquid are improved, and the peeling phenomenon between the tooth cloth and the tooth rubber layer is suppressed. You.

[0023]

Next, the present invention will be described specifically with reference to examples. (Example) Using 40 denier 66 nylon warp yarn (warp yarn, the same applies hereinafter) and 40 denier 66 nylon 66 weft yarn (weft yarn, the same applies hereinafter) at a warp density of 340 yarns / 3cm and a weft yarn density of 119 yarns / 3cm Woven 1 /
Using a canvas having a three-layer twill weave structure, the canvas was vibrated in water and shrunk to about の of the width at the time of weaving (the structure of the canvas is shown in Table 1). Next, this canvas was mixed with RF having the composition shown in Table 2.
Immerse in L liquid, pass between a pair of rolls, 0.5kg / c
m (gauge pressure), dried at 150 ° C. for 4 minutes, and then the RFL-treated canvas was again subjected to R
Immersed in FL solution, squeezed under the same conditions, and then dried under the same conditions,
A tooth cloth having a solid content of RFL of 40% by mass was obtained. The cross cover factor of this tooth cloth was 0.91.

The relationship between the stress and the elongation of this canvas is defined by JIS.
It was measured according to the conditions of L1096. The result at that time is shown in FIG.

Further, as a core wire, about 600 glass fiber filaments having a wire diameter of about 9 μm are bundled to form a strand, and this strand is immersed in an RFL solution having the same composition as above and dried at 200 ° C. for 2 minutes. After doing, 4.0 times / 1
A cord having a diameter of about 0.3 mm twisted with a twist number of 0 cm was used. Then, the above-mentioned tooth cloth is set in a mold in the form of an endless cylinder with the weft in the circumferential direction so that the warp runs along the width direction of the belt, and is set in a mold. It was wound so as to be arranged at a pitch of 0.5 mm, and a rolled sheet made of the rubber composition shown in Table 3 was further wound therefrom, followed by pressurization and vulcanization to produce a sleeve-shaped molded product. This was cut into a predetermined width to obtain a toothed belt having a tooth width of 5 mm and a tooth portion having 500 teeth and a pitch of 1.411 mm.

The toothed belt obtained in this manner has a good tooth shape, and the standard of tooth height is 0.49 mm to 0.2 mm.
With respect to 55 mm, it was 0.538 mm, which was almost at the center of the standard, the rubber was not exposed from the weave of the tooth cloth of the tooth part, and the rubber did not adhere to the surface of the tooth cloth.

(Comparative Example) A weft yarn obtained by aligning and twisting two yarns composed of 40 denier 6 nylon and twisting two yarns composed of 40 denier wooly 6 nylon. Warp density 170 threads / 3cm, weft density 1
A satin woven cloth woven at 75/3 cm was used, and this cloth was vibrated in water to shrink to about の of the width at the time of weaving. Next, RFL was applied to this canvas in the same manner as in the embodiment.
The solution was treated twice to obtain a tooth cloth having a solid content of RFL of 40% by mass. The cross cover factor of the canvas of this tooth cloth was 0.964.

The relationship between the stress and the elongation of this canvas was determined according to JIS.
It was measured according to the conditions of L1096. The result at that time is shown in FIG.

As can be seen from the results shown in FIG. 4, the canvas used in the example is one in the canvas compared to the canvas used in the comparative example.
When a force of 0N or more is applied, it becomes easy to expand. Therefore,
It is considered that the teeth can be more easily formed with respect to the shape of the mold in the process of forming the teeth of the toothed belt.

Using this tooth cloth, an endless cylindrical tooth cloth with a weft thread in the circumferential direction is put on a mold in the same manner as in the embodiment, and the number of teeth is 500 and the pitch is 1.411.
Thus, a toothed belt having a tooth width of 5 mm and a tooth width of 5 mm was obtained. The toothed belt thus obtained had rubber oozing out of the tooth cloth. The tooth height of the tooth portion is 0.49 mm to 0.4 mm.
0.49mm, just below the lower limit for the standard value of 55mm
Met.

[0031]

[Table 1]

[0032]

As described above, the present invention comprises a back rubber portion having a core wire embedded therein and a plurality of tooth rubber portions disposed at a predetermined pitch in the longitudinal direction of the belt on the back rubber portion. A toothed belt comprising a belt body and a tooth cloth adhered to a tooth rubber portion side of the belt body, wherein the tooth cloth uses warp yarns independently twisted one by one, and has a cross cover factor of 0. .9
0 to 0.92, and a toothed belt characterized by using a canvas treated only with a resorcinol-formalin-latex liquid, so that the canvas forming the tooth cloth has a small mesh opening, In addition, even if the tooth cloth is worn for a long period of time and the tooth cloth is worn, it is difficult for the mesh opening to become large, thereby preventing the scattering of the rubber powder due to the mesh opening of the tooth cloth. In addition, there is an effect that the tooth shape is easily formed and the dimensional accuracy of the teeth is increased.

According to the second aspect of the present invention, when the warp of the canvas forms the toothed belt, the toothed belt according to the first aspect runs along the width direction of the toothed belt. From, since the warp is twisted one by one independently,
Without limiting the elongation of the weft yarns along the belt longitudinal direction, the canvas becomes easier to extend in the longitudinal direction of the toothed belt, so that the tooth shape is more likely to appear and the tooth dimensions can be formed more accurately. .

Since the resorcin-formalin-latex liquid having a solid content of 30 to 50% by mass is used as the tooth cloth, the surface of the tooth cloth is coated with the solid resin of the RFL liquid. It is possible to reduce the elongation of the tooth cloth, and it is difficult for the mesh of the tooth cloth to become large, and the effect of preventing the scattering of the rubber powder due to the mesh of the tooth cloth is increased. What you can get.

Furthermore, the density of the warp yarns of the tooth cloth is higher than the density of the weft yarns, and the weaving structure is such that the exposed amount of the twisted yarn extending in the belt width direction and the twisted yarn extending in the belt longitudinal direction are different on both sides of the canvas. It is composed of 1/3 random twill weave,
And since the canvas surface with a large amount of exposed twisted yarn extending in the belt width direction is located on the tooth rubber layer side,
Exposing a large number of warps having a high density on the belt surface side, that is, on the side in contact with the pulley, has an effect of suppressing rubber bleeding on the belt surface and has an effect of improving abrasion resistance. In addition, since a large number of weft yarns having a lower density than the warp yarns are exposed on the tooth rubber layer side, the adhesiveness with the tooth rubber layer and the impregnation of the treatment liquid are improved, and the tooth cloth and the tooth rubber layer are separated. There is an effect that the phenomenon is suppressed.

According to the fifth aspect of the present invention, since the density of the warp yarn of the tooth cloth is about three times the density of the weft yarn, when the weave structure is 1/3 random twill weave, the density of the warp yarn on the belt tooth surface is reduced. It is more effective in suppressing rubber bleeding, abrasion resistance of the belt, and suppressing the phenomenon of peeling between the tooth cloth and the tooth rubber layer.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing an example of an embodiment of a toothed belt.

FIG. 2 is a weave organization diagram of a 1/3 random twill weave fabric.

FIG. 3 is a weave organization diagram of a 2/2 twill weave cloth.

FIG. 4 is a graph showing a relationship between an elongation ratio in a lateral direction of a canvas and stress.

[Description of Signs] 1 core wire 2 belt body 3 tooth section 4 tooth bottom section 5 tooth cloth

 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shin Hasegawa 4-1-1-21 Hamazoedori, Nagata-ku, Kobe City, Hyogo Prefecture Inside Mitsuboshi Belting Co., Ltd.

Claims (5)

[Claims] 1. A belt body comprising a back rubber portion in which a core wire is embedded, and a plurality of tooth rubber portions disposed on the back rubber portion at a predetermined pitch in the longitudinal direction of the belt. A toothed belt having a tooth cloth adhered to the tooth rubber part side, wherein the tooth cloth uses warp yarns that are individually twisted one by one, and a cross cover factor is 0.90 to 0.92, A toothed belt using a canvas treated only with a resorcin-formalin-latex liquid. 2. The toothed belt according to claim 1, wherein when the warp yarns of the canvas form a toothed belt, the toothed belt runs along the width direction of the toothed belt. 3. The toothed belt according to claim 1, wherein the resorcin-formalin-latex liquid having a solid content of 30 to 50% by mass is used as the tooth cloth. 4. The density of warp yarns of the tooth cloth is higher than the density of weft yarns, and the weaving organization is such that the amount of exposure of the twist yarns extending in the belt width direction and the twist yarns extending in the belt longitudinal direction are different on both sides of the tooth cloth. As described above, the tooth cloth surface having a large amount of twisted yarn extending in the belt width direction is formed on the outer side, and the tooth cloth surface having a large amount of twisted yarn extending in the belt longitudinal direction is formed on the tooth rubber layer side. Claim 1 which is located in each
4. The toothed belt according to any one of items 1 to 3. 5. The toothed belt according to claim 4, wherein the density of the warp yarn of the tooth cloth is approximately three times the density of the weft yarn.