JP4851134B2 - V-ribbed belt and manufacturing method thereof - Google Patents

Description

The present invention relates to a V-ribbed belt and a manufacturing method thereof.

For example, a V-ribbed belt used in the belt-type accessory drive system of an automobile engine which require grinding and polishing process includes a grinding step by the generally V-ribbed belts for biaxial grinding machine in the manufacturing process .
Specifically, the vulcanization sleeve as illustrated in FIG. 1 is rotated in a state of being wound around the drive roll and the driven roll, and the vulcanization sleeve is brought into contact with the vulcanization sleeve by contacting the rotating grinding wheel. Grind. The conventional biaxial grinding machine that has been used in such a grinding process is set so that both the grinding wheel and the drive roll rotate at a constant speed as shown in FIG.

However, in general, any machined rotating body necessarily has a slight runout, and the above-mentioned grinding wheel provided in the biaxial grinding machine is no exception, usually about 0.05 mm. Has a core blur.
Further, when the grinding wheel and the drive roll are rotating at a constant speed as described above, a striped pattern (uneven portion) caused by the core blur is formed on the surface to be ground of the vulcanization sleeve as shown in FIG. It will be formed periodically.
Due to this periodic stripe pattern, annoying high-frequency noise is generated during belt running.

  On the other hand, the quietness of automobile engines has been greatly improved, and accordingly, measures for suppressing the running noise of the belt itself have been required.

Therefore, Patent Document 1 discloses a power transmission belt for the purpose of efficiently reducing an abnormal noise generated particularly when the belt travels. This power transmission belt has a concave portion in the belt bottom surface in the belt thickness direction on the bottom surface of the belt, and is adjacent to the concave portion in the belt length direction and protrudes on the opposite side of the belt main body in the belt thickness direction. The amount of unevenness, which is the dimension in the belt thickness direction between the convex portions in the finished state, is 40 μm or less, respectively.
JP 2000-205340 A (Claim 1)

However, Patent Document 1 does not describe any specific technical disclosure for suppressing the unevenness to 40 μm or less.
The main object of the present invention is to suppress the above-mentioned noise generated during belt running.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

In a V-ribbed belt in which a plurality of ribs extending in the belt longitudinal direction are arranged side by side in the width direction, the belt bottom surface of the V-ribbed belt has a recess depressed in the belt main body side in the belt thickness direction, and the recess Concave and convex portions, which are adjacent to the belt longitudinal direction and are continuously formed in the belt longitudinal direction, are formed of convex portions that are raised on the side opposite to the belt main body side in the belt thickness direction. The concavo-convex portions are different in length in each direction , and the concavo-convex portion is run under a predetermined tension by winding an annular vulcanization sleeve having a core wire embedded in a rubber layer around a driving roll and a driven roll. When the surface of the vulcanization sleeve is ground by bringing a rotating grinding wheel into contact with the vulcanization sleeve while rotating eccentrically by the core blur, the striped pattern is formed corresponding to the core blur. Belt longitudinal length of the serial uneven portion, one of the rotational speed of at least one of the grinding wheel or the drive roll is intended to vary by varying during grinding.

During the running of more of the V-ribbed belt by arrangement, noise caused by the uneven portion in the longitudinal direction are continuously formed in the belt, it is possible to particularly suppress the occurrence of high frequency noise at specific frequencies. Further, since the annoying noise is suppressed, for example, the comfort in an automobile can be greatly improved.
In addition, this makes it possible to obtain the V-ribbed belt that combines the high transmission performance of the V-belt and the flexibility of the flat belt.

An annular vulcanization sleeve in which a core wire is embedded in a rubber layer is wound around a drive roll and a driven roll and travels under a predetermined tension, and the grinding wheel rotates while being eccentric by the core blur on the traveling vulcanization sleeve It was allowed to abut made by grinding the surface of the vulcanized sleeve, in the manufacturing method of the V-ribbed belt ribs plural rows extending in belt longitudinal direction are arranged in the width direction, of the grinding wheel or the drive roll varying at least one of the rotational speed during grinding, the belt bottom surface of the V-ribbed belt, a concave portion in a state of depression in the belt main body of the belt thickness direction, adjacent to the belt longitudinal direction to the recess, the belt the thickness direction of the belt main body a concave-convex portion striped pattern consisting of a convex portion in a state in which raised the opposite side, the belt longitudinal direction different uneven portions belt longitudinal direction length, respectively Continuously formed.

Even if they are produced in the grinding wheel eccentrically Thus, noise caused by the uneven portion in the longitudinal direction are continuously formed in the belt during the running of the V-ribbed belt, in particular of high-frequency noise at specific frequencies occur Can be suppressed. Further, since the annoying noise is suppressed, for example, the comfort in an automobile can be greatly improved.
Further, in order to suppress the generation of the noise, it is only necessary to change the rotational speed of the grinding wheel or the driving roll during grinding, so that the time and cost required for production hardly increase.
This also makes it possible to manufacture the V-ribbed belt that combines the high power transmission of the V-belt and the flexibility of the flat belt.

Hereinafter, it described with respect to the embodiment of the V-ribbed belt according to the present invention with reference to the drawings.

  First, an annular vulcanization sleeve 1 as a material of a V-ribbed belt will be described with reference to FIG. FIG. 1 is a cross-sectional perspective view showing the configuration of the vulcanization sleeve. The vulcanization sleeve 1 is formed of a canvas forming a cover canvas 5, a rubber sheet forming an adhesive rubber layer 3, and an adhesive-treated twist forming a core wire 2 on the outer peripheral surface of a cylindrical forming drum (not shown). A cord and a rubber sheet forming the compressed rubber layer 4 are wound in order, and the resulting molded body is obtained by vulcanization by a known heating and pressing means.

  As the compressed rubber layer 4, for example, chloroprene rubber (CR), ethylene propylene rubber (EPDM), chlorosulfonated polyethylene (CSM), alkylated chlorosulfonated polyethylene (ACSM), hydrogenated nitrile rubber (HNBR), etc. are used. It is done. The compressed rubber layer 4 is desirably mixed with short fibers such as nylon 6, nylon 66, polyester, cotton, and aramid to improve the side pressure resistance.

As the cord constituting the core 2, for example, a twisted cord made of a fiber such as polyethylene terephthalate (PET) fiber or polyethylene-2,6-naphthalate (PEN) is used. The core wire 2 is embedded in the adhesive rubber layer 3.
As the cover canvas 5, a cloth woven into a plain weave, twill weave, satin weave, or the like using yarn made of cotton, polyamide, polyethylene terephthalate, or aramid fiber is used.

  Next, a process of grinding the surface of the vulcanized sleeve 1 produced as described above to form a rib portion will be described with reference to FIGS. FIG. 2 is a side view showing how the vulcanized sleeve is ground, FIG. 3 is a view showing the rotational speed of the grinding wheel and the drive roll in the biaxial grinding machine, and FIG. 2B is a modification of FIG. FIG. 4 is a diagram showing an example, and FIG. 4 is a sectional view taken along line 4-4 of FIG.

  In this process, as in the biaxial grinding machine shown in FIG. 2, the vulcanization sleeve 1 is applied with an appropriate tension between the driving roll 11 (corresponding to the main axis of the biaxial grinding machine) and the driven roll 12. Wrap it around. The vulcanization sleeve 1 is wound around both rolls 11 and 12 so that the rubber sheet forming the compressed rubber layer 4 shown in FIG.

  In the state of FIG. 2, the drive roll 11 is rotated in the direction of the thick arrow to cause the vulcanization sleeve 1 to travel in the direction of the outlined arrow, and the grinding wheel 13 disposed in the vicinity of the drive roll 11 is moved to the drive roll 11. In the same direction (or the opposite direction). The grinding wheel 13 has a core blur of about 0.05 mm.

Here, the rotational speeds of the drive roll 11 and the grinding wheel 13 are set as follows as shown in FIG. That is, the rotation speed of the grinding wheel 13 is set to 1800 rpm, for example, so that it always rotates at a constant speed during grinding. On the other hand, the rotational speed of the drive roll 11 is always changed during grinding. Specifically, the rotational speed of the drive roll 11 has an amplitude of 10 to 100 rpm and changes like a sine wave having a fluctuation period of 3 to 60 sec. Is set.
Instead of this, as shown in FIG. 3B, it may be set as follows. That is, the rotational speed of the drive roll 11 is set to, for example, 10 to 100 rpm so that it always rotates at a constant speed during grinding. On the other hand, the rotational speed of the grinding wheel 13 always fluctuates during grinding. The speed may be set so as to fluctuate like a sine wave having an amplitude of 300 to 3000 rpm and a fluctuation period of 3 to 60 sec.
Furthermore, it may be considered that the drive roll 11 and the grinding wheel 13 always fluctuate during grinding.

  In addition, diamond grinding grains are electrodeposited on the surface of the grinding wheel 13, and as shown in FIG. 4 as a sectional view taken along line 4-4 in FIG. , 50 to 150) V-shaped projections 14 are formed. Then, the grinding wheel 13 is rotated and brought into contact with the surface of the traveling vulcanization sleeve 1, and the portion of the protrusion 14 is cut into the compressed rubber layer 4 to be ground to form a groove. As a result, a large number of protrusions that become the rib portions 7 are formed on the compressed rubber layer 4 of the vulcanization sleeve 1. In other words, a plurality of rib portions 7 (ribs) extending in the belt longitudinal direction are formed side by side in the width direction on the belt bottom surface described later.

  The vulcanized sleeve 1 in which the rib portion 7 is formed in this manner can be cut into rounds at predetermined widths, whereby a finished V-ribbed belt 10 as shown in FIG. 5 can be obtained.

  By the way, the belt bottom surface 8 which is a surface to be ground at the tip of the rib portion 7 will be described with reference to FIG. FIG. 6 is a side view seen from the thick arrow 6 in FIG. 5, and is a schematic diagram in which the uneven state of the surface to be ground is exaggerated.

As described above, since the grinding wheel 13 has a slight core blur, each time the grinding wheel 13 makes one revolution, one recess is formed in the belt bottom surface 8. As shown in FIG.
More specifically, the belt bottom surface 8 has a recess 8a that is depressed in the belt thickness direction (vertical direction in FIG. 6) on the side of the belt body, that is, in a direction approaching the adhesive rubber layer 3 and the cover canvas 5; A concave / convex portion 8c, which is adjacent to the concave portion 8a in the longitudinal direction of the belt (left and right direction in FIG. 6) and includes a convex portion 8b that protrudes on the opposite side of the belt main body in the belt thickness direction, repeats in the longitudinal direction of the belt. Formed continuously.
At this time, by changing the driving roll 11 or the grinding wheel 13 during grinding as shown in FIG. 3A, the above-mentioned concavo-convex portion 8c formed continuously in the belt longitudinal direction has a pitch (length in the belt longitudinal direction). A) P is formed to be different in the range of 3.1 to 6.3 mm. In short, the pitch P of the stripe pattern formed on the belt bottom surface 8 is an unequal pitch.
In addition, the range of the pitch P of the said uneven | corrugated | grooved part 8c can be freely set by changing conditions, such as the rotational speed of the drive roll 11 or the grinding wheel 13, suitably.

Even when manufactured with the grinding wheel 13 decentered as described above, the striped pattern is formed at an equal pitch during belt running by making the pitch P of the striped pattern formed by the core blurring of the grinding wheel 13 unequal. Compared with the case where it appears in the shape (see FIGS. 7 and 8), noise caused by the uneven portion 8c formed continuously in the longitudinal direction of the belt, particularly high frequency noise in a specific frequency band Can be suppressed.
Further, since the annoying noise is suppressed, for example, the comfort in an automobile can be greatly improved.
Further, in order to suppress the generation of the noise, it is only necessary to change the rotational speed of the grinding wheel 13 or the drive roll 11 during grinding, so that the time and cost required for manufacturing hardly increase.

As shown in FIG. 3 (a), in the present embodiment, the drive roll 11 (or the grinding wheel 13) is set so as to fluctuate like a sine wave during grinding. Instead, it may be set to fluctuate like a triangular wave or a sawtooth wave, for example.
Further, these sine wave, triangular wave, and sawtooth wave may be changed aperiodically (randomly) instead of periodically changing.

  In the case of the rotational speed condition shown in FIG. 7, which is set in the conventional two-axis grinding machine, that is, the condition that both the grinding wheel (1800 rpm) and the driving roll (15 rpm) are rotating at a constant speed, the pitch of the stripe pattern described above is used. P is a constant value of 4.7 mm. Due to this, the transmission belt generates high-frequency noise in a specific frequency band during belt running.

The cross-sectional perspective view which shows the structure of a vulcanization sleeve. The side view which shows the mode of grinding of a vulcanization sleeve. (A) is a figure which shows the rotational speed of the grinding roll and drive roll in a biaxial grinding machine, (b) is a figure which shows the modification of (a). FIG. 4 is a sectional view taken along line 4-4 in FIG. The cross-sectional perspective view which shows the structure of the completed V-ribbed belt. FIG. 6 is a side view seen from a thick arrow 6 in FIG. 5, and is a schematic diagram in which the uneven state of the surface to be ground is exaggerated. The figure which shows the rotational speed of the grinding roll and drive roll in the conventional biaxial grinding machine. It is a side view of the conventional V ribbed belt, Comprising: The schematic diagram drawn exaggerating the uneven | corrugated state of the to-be-ground surface.

DESCRIPTION OF SYMBOLS 1 Vulcanization sleeve 2 Core wire 3 Adhesive rubber layer 4 Compression rubber layer 8 Belt bottom surface 8a Concave portion 8b Convex portion 8c Concavity and convexity portion 10 V-ribbed belt 11 Drive roll 12 Driven roll 13 Grinding wheel

Claims (2)

In the V-ribbed belt in which a plurality of ribs extending in the belt longitudinal direction are arranged in parallel in the width direction,
On the belt bottom surface of the V-ribbed belt, there is a recess recessed in the belt body direction in the belt thickness direction, and the recess is adjacent to the recess in the longitudinal direction of the belt and is raised on the side opposite to the belt body side in the belt thickness direction. The uneven part consisting of the convex part of the state is continuously formed in the belt longitudinal direction,
The lengths in the belt longitudinal direction of the uneven portions are different from each other,
The concavo-convex portion is decentered by the core blurring of the traveling vulcanization sleeve by running an annular vulcanization sleeve with a core wire embedded in the rubber layer around a driving roll and a driven roll under a predetermined tension. While grinding the surface of the vulcanization sleeve while abutting a rotating grinding wheel, it is a striped pattern formed corresponding to the core blur,
The V-ribbed belt is characterized in that the length of the concavo-convex portion in the longitudinal direction of the belt is varied by changing the rotational speed of at least one of the grinding wheel or the drive roll during grinding. An annular vulcanization sleeve in which a core wire is embedded in a rubber layer is wound around a drive roll and a driven roll and travels under a predetermined tension, and the grinding wheel rotates while being eccentric by the core blur on the traveling vulcanization sleeve In a method for manufacturing a V-ribbed belt, in which a plurality of ribs extending in the belt longitudinal direction are juxtaposed in the width direction, and the surface of the vulcanization sleeve is ground by abutting
The rotational speed of at least one of the grinding wheel or the drive roll is varied during grinding,
On the belt bottom surface of the V-ribbed belt, a recess recessed in the belt main body side in the belt thickness direction, a state adjacent to the concave portion in the longitudinal direction of the belt and raised on the opposite side of the belt main body side in the belt thickness direction A method for producing a V-ribbed belt , wherein uneven portions having a striped pattern composed of a plurality of convex portions and having uneven lengths in the belt longitudinal direction are continuously formed in the belt longitudinal direction.

Images