JP2002039291A - V-ribbed belt driver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a V-ribbed belt enhancing transmitting force of a belt and extending a service life of the belt by suppressing slips of the belt and reducing abnormal sounds. SOLUTION: In this V-ribbed belt driver 1 with the V-ribbed belt 8 suspended between a V-ribbed pulley 9 having V-rib grooves 11 used as a driving pulley and at least one driven pulley, a pitch P between ribs 7 of the V-ribbed belt 8 is 90-95% in size to a pitch P' between the rib grooves 11 of the V-ribbed pulley 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a V-ribbed belt driving device, and more particularly to a V-ribbed belt driving device which suppresses sound generation and slip even under a low tension of a belt and improves transmission power.

[0002]

2. Description of the Related Art A V-ribbed belt has a core wire buried in an adhesive rubber layer, a cover canvas is laminated on the upper portion of the adhesive rubber layer as required, and a plurality of rib portions are provided below the adhesive rubber layer. Is provided. The V-ribbed belt has been widely used in place of the V-belt for power transmission of a multi-shaft drive such as a water pump or a generator of an automobile. Conventionally, in order to efficiently transmit the power of the belt, it is necessary to reduce the slip ratio between the belt and the pulley, and the belt tension is increased to reduce the slip ratio. In addition, when the vehicle is running in the rain, water enters the engine room, water adheres between the belt and the pulley, and the belt slips, so that a slip noise is generated.

[0003] Furthermore, the current automobile is becoming quieter,
In particular, sounds other than engine sounds are regarded as abnormal sounds. Therefore, the belt tension is increased to reduce the slip ratio so that the belt noise caused by water does not occur even if water enters the engine room during traveling in rain.

[0004]

However, when the belt tension is increased, when the belt shrinkage stress during dry heating is increased, the belt dry heat shrinkage rate increases and the belt length shrinks with time. did. Further, in the conventional multi-axis drive device, a V-ribbed belt having a cord of polyethylene terephthalate fiber as a cord is suspended, and a belt separated from a pulley of a generator having a large rotational inertia generates a large inertia torque and power generation. It was instantaneously stretched to carry the torque, and caused abnormal noise due to the resonance phenomenon occurring between the pulleys on the slack side.

[0005] In the conventional belt, as described above, the type of the core wire is changed, the belt tension is increased, the rubber composition is changed, and the rib shape is changed. However, other problems such as poor durability have occurred. By focusing on the belt rib pitch this time, it is intended to take measures against sound generation by changing the ratio of the belt rib pitch and the pulley rib groove pitch which are conventionally the same size.

Accordingly, the present invention has been made to solve such a problem, and in order to cope with the problem, the belt transmission force and the belt life are extended by suppressing the slip of the belt and reducing abnormal noise. It is intended to provide a ribbed belt.

[0007]

That is, the invention according to claim 1 of the present application provides an adhesive rubber layer in which a core wire is embedded along an extension portion and a longitudinal direction of the belt, and a peripheral portion of the belt adjacent to the adhesive rubber layer. A V-ribbed belt including a compression section having a plurality of ribs extending in a direction, a V-ribbed belt driving device suspended from a driving pulley and at least one driven pulley, wherein a pitch between the ribs of the V-ribbed belt is between rib grooves of the pulley. In a V-ribbed belt drive that is 90-95% of the pitch.

According to the first aspect of the present invention, since the pitch between the ribs of the V-ribbed belt is 90 to 95% of the pitch between the rib grooves of the pulley, the V-ribbed belt driving device is used. As the surface pressure on the pulley increases, the coefficient of friction of the V-ribbed belt with respect to the pulley increases, and it is possible to reduce the sound generation by suppressing the slip at the time of starting and stopping.

[0009]

FIG. 1 is a sectional perspective view showing a V-ribbed belt used in a V-ribbed belt driving device according to the present invention. FIG. 2 is a sectional view showing a V-ribbed belt driving device according to the present invention. In FIG. 1, a V-ribbed belt 8 is composed of an extension portion 2 made of a cover canvas 3, an adhesive rubber layer 5 in which a cord 4 made of a cord is buried, and a compression rubber layer 6 which is an elastic material layer under the extension portion. I have. In the compressed rubber layer 6, a plurality of trapezoidal ribs 7 having a substantially triangular cross section extending in the longitudinal direction of the belt are arranged at a pitch P in the belt width direction.

FIG. 2 is a sectional view showing a V-ribbed belt driving device according to the present invention. The V-ribbed pulley 9 on which the V-ribbed belt 8 is suspended has a plurality of V-ribs 7 on which the V-ribs 7 of the V-ribbed belt 8 are fitted. V-rib grooves 11 are formed at a pitch P '.

The pitch P between the V-ribs 7 of the V-ribbed belt 8 is 90 to 95% of the pitch P 'between the V-rib grooves 11 of the V-ribbed pulley 9. By doing so, the surface pressure at which the belt rib surface presses the pulley rib groove surface when the V-ribbed belt 8 is fitted to the V-ribbed pulley 9 increases, and the friction coefficient of the V-ribbed belt 8 against the V-ribbed pulley 9 increases. Suppression of the slip at the time of stop can reduce sound generation.

The V rib 7 has a hydrogenated nitrile rubber,
Chloroprene rubber, natural rubber, CSM, ACSM, SB
R is used, and hydrogenated nitrile rubber has a hydrogenation rate of 80%.
In order to exhibit the heat resistance and ozone resistance characteristics, it is preferably 90% or more. 80% hydrogenation rate
If the hydrogenated nitrile rubber is less than 1, heat resistance and ozone resistance are extremely reduced. In consideration of oil resistance and cold resistance, the amount of bound acrylonitrile is preferably in the range of 20 to 45%.

Further, short fibers made of cotton are mixed in the V-ribs 7 to improve the lateral pressure resistance of the V-ribs 7. Furthermore, short cotton fibers can be made to protrude from the surface of the V-rib 7 to absorb water adhering to the surface of the V-rib 7. As the short fibers, nylon 6, nylon 66, polyester, and meta-aramid fibers can be used in addition to cotton.

In order to improve the adhesion between the V-rib 7 and the rubber, the short cotton fibers are bonded with a treatment liquid selected from an epoxy compound and an isocyanate compound.

Further, as the core wire 4, a polyester fiber, an aromatic polyamide fiber, a glass fiber or the like can be used. These core wires 4 are subjected to an adhesive treatment for the purpose of improving the adhesiveness with rubber. As such an adhesive treatment, a fiber is resorcin-formalin-latex (R
(FL solution), and then dried by heating to form an adhesive layer uniformly on the surface. However, without being limited to this, there is a method of performing a pre-treatment with an epoxy compound or an isocyanate compound and then treating with an RFL solution.

Examples of the epoxy compound include polyhydric alcohols such as ethylene glycol, glycerin, and pentaerythritol; reaction products of polyalkylene glycols such as polyethylene glycol with halogen-containing epoxy compounds such as epichlorohydrin; (4-hydroxyphenyl) dimethylmethane,
It is a reaction product with polyhydric phenols such as phenol-formaldehyde resin and resorcin-formaldehyde resin and halogen-containing epoxy compounds. This epoxy compound is used by being mixed with an organic solvent such as toluene and methyl ethyl ketone.

The RFL solution is obtained by mixing a latex with an initial condensate of resorcinol and formalin, and the latex used herein includes chloroprene, styrene / butadiene / vinylpyridine terpolymer, hydrogenated nitrile, NBR, etc. It is.

The cord subjected to the stretching heat setting treatment has a spinning pitch, that is, a core winding pitch of 1.0 to 1.0 mm.
By setting the thickness to 1.3 mm, a belt having a high modulus can be finished. If it is less than 1.0 mm, the cord cannot ride on the adjacent cord and cannot be wound,
On the other hand, if it exceeds 1.3 mm, the modulus of the belt gradually decreases.

The cover canvas 3 is a fabric woven in a plain weave, a twill weave, a satin weave, or the like using a yarn made of cotton, polyamide, polyethylene terephthalate, and aramid fiber.

[0020]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Examples 1 and 2 and Comparative Examples 1 and 2 As Examples 1 and 2 and Comparative Examples 1 and 2, the sound at the start and stop of the belt when the level of the rib pitch of the belt was varied was examined.

Here, the V-ribbed belt 8 has a cord 4 made of a polyester fiber rope embedded in an adhesive rubber layer 5, a cotton sail cloth 4 with rubber laminated thereon in one ply, and the other side of the adhesive rubber layer 5. A compression rubber layer 6 is provided on the lower side, and three V-ribs 7 are arranged in a line along the longitudinal direction of the belt. The obtained V-ribbed belt 8 has a length of 30 mm according to the RMA standard.
K-type three-ribbed belt of Table 2
Has the rib pitch described in (1).

The compressed rubber layer 6 has the composition A shown in Table 1, and the adhesive rubber layer 5 has the composition B shown in Table 1. Also,
The short fibers in the compressed rubber layer 6 use meta-aramid fibers,
After kneading with a Banbury mixer, what was rolled with a calendar roll was used. The compressed rubber layer 6 contains short fibers and is oriented in the width direction. The belt according to the present embodiment is
It is manufactured by a conventional method known in the art. First, one ply of cotton canvas with rubber is wrapped around a flat cylindrical mold, and then an adhesive rubber layer is wrapped, and the cord is spun to form a compressed rubber layer. After installing, a jacket for vulcanization is inserted on the compressed rubber layer. Next, the molding mold is placed in a vulcanization can, and vulcanized at 150 ° C. for 30 minutes. Then, the cylindrical vulcanization sleeve is taken out of the mold, and the compressed rubber layer of the sleeve is formed into a rib by a grinder, and is formed. It consists of cutting the body into individual belts.

[0023]

[Table 1]

Then, a belt having five types of rib pitches was manufactured by changing the pitch of the protrusions of the grindstone for forming the belt rib groove of the grindstone of the grinder. Table 2 shows the rib pitch levels.

Next, a sound test was performed using these belts. The pronunciation test uses a real car engine,
The test was performed with the layout as shown in FIG. As for the evaluation of pronunciation, the presence or absence of pronunciation at the time of starting and stopping the engine was examined. As a measuring method, a method was used in which a person heard and judged with an ear as an auditory sense. Table 2 shows the results.

[0026]

[Table 2]

As can be seen from Table 2, it can be seen that the embodiment does not emit any sound at the time of startup and at the time of stop.

Next, the dynamic friction coefficient and the static friction coefficient of the V-ribbed belt manufactured as described above were measured.
As shown in FIG. 4 (a), the dynamic friction coefficient was measured by cutting the V-ribbed belt 1 to a length of 300 ± 50 mm.
This V-ribbed belt 8 is suspended by contacting it with a 0 mm rib grooved pulley within an angle range of 45 °, and a weight 27 is attached to the lower end of the V-ribbed belt 8 to apply a 19.6 N pulling force to the V-ribbed belt 8 to 30 mm. / Sec
It was performed by pulling at the speed shown below and calculating from the torque value of the pulley measured at this time. Further, the measurement of the coefficient of static friction was performed as shown in FIG.
17. The V-ribbed belt 8 is suspended by making contact with the V-rib grooved pulley 25 at an angle range of 90 °, one end of the V-ribbed belt 8 is fixed, and a weight 29 is attached to the other end.
While applying a tensile force of N, pulley 2 with V-rib groove
5 was rotated at 43 rpm, and was calculated from the torque value of the V-rib grooved pulley 25 measured within 5 to 30 seconds after the rotation of the V-rib grooved pulley 25 was started. Table 3 shows the measurement results.

[0029]

[Table 3]

It can be seen that Examples 1 and 2 both have a higher dynamic friction coefficient and a higher static friction coefficient than Comparative Example 1.

Next, a V-ribbed belt was suspended on a pair of V-ribbed pulleys, and the transmittable torque of the belt was measured. φ8
0mm drive side pulley is rotated at 2000rpm, φ
A load was applied to the driven pulley of 110 mm, and the torque was measured when the belt slipped by 2% at a belt tension of 34.3 N / rib. The result is shown in FIG.

As can be seen from FIG. 5, the transmittable torques of the first and second embodiments are larger than those of the conventional example. However, when the rib pitch of the belt is smaller than that of the third embodiment, a sharp decrease in the transmittable torque is recognized.

[0033]

As described above, in the invention according to the first aspect of the present invention, the pitch between the ribs of the V-ribbed belt is 90 to 95% of the pitch between the rib grooves of the pulley. As the surface pressure on the pulley increases, the coefficient of friction of the V-ribbed belt with respect to the pulley increases, and there is an effect that sound generation can be reduced by suppressing slippage at the time of starting and stopping.

[Brief description of the drawings]

FIG. 1 shows a V used in a V-ribbed belt driving device according to the present invention.
It is a sectional perspective view of a ribbed belt.

FIG. 2 is a schematic diagram showing a driving device using the V-ribbed belt of the present invention.

FIG. 3 is a layout diagram of a pronunciation test.

FIG. 4 (a) is a schematic diagram showing the measurement of the coefficient of dynamic friction,
(B) is a schematic diagram showing measurement of a static friction coefficient.

FIG. 5 is a graph showing a relationship between a belt pitch and a transmittable torque ratio.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 V-ribbed belt drive device 2 Extension part 3 Cover canvas 4 Core wire 5 Adhesive rubber layer 6 Compressed rubber layer 7 V-rib 8 V-ribbed belt 9 V-ribbed pulley 11 V-rib groove 13 Crankshaft pulley 15 Idler pulley 17 Auto tensioner 19 Alternator 21 Air-conditioner drive Pulley 23 Power steering drive pulley 25 Pulley with V-rib groove 27 Weight 29 Weight

Claims (1)

[Claims] 1. A V-ribbed belt comprising: a stretching portion; an adhesive rubber layer having a core buried along a longitudinal direction of the belt; and a compression portion having a plurality of ribs extending in the circumferential direction of the belt adjacent to the adhesive rubber layer. A V-ribbed belt driving device suspended on a driving pulley and at least one driven pulley, wherein a pitch between ribs of the V-ribbed belt is 90 to 95% of a pitch between rib grooves of the pulley. .