JP3090258U - V-ribbed belt - Google Patents

Abstract

(57) [Problem] To provide a V-ribbed belt in which a contact state between a belt and a pulley is optimized to improve transmission capacity and reduce sound generation. SOLUTION: In a V-ribbed belt having at least a plurality of ribs, a rib height h 'of at least ribs at both ends and a rib height h of a rib at a central portion are different from each other.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention optimizes the contact state between the belt and the pulleys by changing the rib height at both ends and the rib height at the center of the V-ribbed belt for power transmission, thereby improving the transmission capacity and reducing sound generation. It relates to a V-ribbed belt.

[0002]

[Prior art]

 A combination of a V-ribbed belt and a V-ribbed pulley is used as a transmission power system for driving the auxiliary equipment of a vehicle engine. However, the V-ribbed pulley provided to a generator (alternator) increases the number of electric devices. In order to increase power consumption, the pulley rotation speed is increased by reducing the diameter of the pulley. In addition, the diameter of the pulley has been reduced in order to secure the amount of power generation at the time of idle reduction to improve fuel efficiency. Furthermore, in the hybrid system, the diameter of the pulley has been reduced in order to generate the vehicle starting torque by reducing the speed from the starter / generator via the belt.

On the other hand, the other pulley diameters are about φ100 mm to φ140 mm, and the change in the rib angle due to the rib rubber deformation at the time of winding and bending of the belt differs for each pulley diameter. Is considered non-uniform.

A current V-ribbed belt used for driving accessories of a vehicle engine has a configuration in which a plurality of substantially trapezoidal cross-section ribs protrude from an inner peripheral portion of the belt as shown in FIG. The ribs of the V-ribbed belt have a problem in that frictional heat generated due to the contact between the belt and the pulley accumulates inside the belt, which causes thermal aging of the belt, thereby causing early failure of the belt.

[0005]

[Problems to be solved by the invention]

 The present invention has been made in view of such a situation, and provides a V-ribbed belt in which a contact state between a belt and a pulley is optimized to improve transmission capacity and reduce sound generation.

[0006]

[Means for Solving the Problems]

 The present invention according to claim 1 is a V-ribbed belt having at least a plurality of ribs, wherein at least a rib height at both ends and a rib height at a central portion are different.

According to the first aspect of the present invention, at least the rib height at both ends and the rib height at the center are different from each other in the V-ribbed belt. Since it is different from the rib, a good contact state can be secured for a wide range of pulley diameters.

[0008]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described. FIG. 1 shows one embodiment of the V-ribbed belt 1 according to the present invention, and FIG. 2 shows another embodiment of the V-ribbed belt 1 according to the present invention. In FIG. 1, the V-ribbed belt 1 has a low rib height h 'at both ends and a high rib height h at the center. In this case, in the pulley having a large pulley diameter, when the rib 7 at the center is compressed, the change in the angle of the rib 7 at the center becomes large, whereby the contact between the rib 4 at both ends and the pulley is made. Also gets better.

In the V-ribbed belt 9 shown in FIG. 2, the ribs 4 at both ends of the pulley having a small pulley diameter are compressed, and the rib angles at both ends are changed. And the contact state with the battery is improved.

Here, it is preferable that the lower rib height is 50% to 80% of the height of the higher rib. If the height of the lower rib is smaller than 50% of the height of the higher rib, there is a problem that the transmission force of the lower rib is insufficient. On the other hand, if the height of the lower rib is larger than 80%, the deformation of the rib peak is small and the effect is small. There is a problem.

As is well known, the V-ribbed belt includes a cushion rubber layer 3 embedded with a top cover cloth 5, a low elongation and high strength tensile rope 2 made of polyester fiber, nylon fiber, and aromatic polyamide fiber from above. The bottom surface is formed of a plurality of V-shaped rib groups that extend in parallel with the longitudinal direction of the belt and form a compression layer of a belt fitted with a V-shaped grooved pulley.

[0012] The rib portions of the belt which have facing friction drive surfaces 11 and 11 on both sides and which fit into the V-shaped grooves of the pulley, respectively, are formed of NR, SBR, butadiene rubber, chloroprene rubber, similarly to the cushion rubber layer 3. Chlorosulfonated polyethylene, water-added NBR, etc. in a single material, or a rubber material obtained by appropriately blending them, the short fiber group of 5 to 50 parts by mass with respect to 100 parts by mass of the rubber material is used. Are buried while maintaining the orientation in the belt width direction. In addition, 80% or more of the short fibers are composed of, in particular, aramid short fibers. Further, the aramid fibers are so-called aramid short fibers which are liable to fibrillate, in which the filaments are apt to be broken in the length direction and become thin. It is distinguished from aramid short fibers that are difficult to fibrillate.

[0013]

【Example】

 Hereinafter, the present invention will be described in more detail with reference to specific examples. Example 1 As a cover cloth, a fiber in which cotton and polyester were mixed was used. Polyester was used as the cord, and the pitch between the cords was 1.1 mm. Chloroprene rubber was used for the cushion rubber, and chloroprene rubber was also used for the rubber of the rib portion. As the belt, a 6-ribbed belt having a J-shaped rib star belt and a belt length of 1000 mm was used. At this time, the rib height of the center rib was 2.7 mm, and the rib height at both ends was 2.0 mm. The rib angle was 40 °.

Example 2 The same cloth as that of Example 1 was used for the cover cloth, the core wire, the cushion rubber, and the rubber of the rib portion. The pitch between the cords was the same as in Example 1. The belt size was the same as in Example 1. The height of the rib at the center was 2.7 mm, and the height of the two ribs at both ends was 2.0 mm. The rib angle was the same as in Example 1.

As a conventional example, the same cover cloth, core wire, cushion rubber, and rubber of the rib portion as those of the first embodiment were used, and the pitch between the core wires, the belt size, and the rib angle were also the same as those of the first embodiment. . The rib height at the center and the rib height at both ends were the same and were 2.0 mm.

The V-ribbed belt thus obtained was subjected to a running test with the V-ribbed belt thus obtained in the layout shown in FIG. 3, and the load was increased with a constant axial load. Was measured. This value is an indicator of transmissibility, and the higher the load, the less slippage the higher the transmission performance.

As a result, when the tension was set to 29 N / rib, the load at the time of 2.0% slip was 3.3 KW in both Examples 1 and 2, the conventional example was 3.0 KW, and the transmission force was compared with the conventional example. Thus, both Examples 1 and 2 are about 10% larger.

Next, the V-ribbed belt is formed into a three-shaft consisting of a driving pulley (140 mm in diameter) shown in FIG. 3, a driven pulley (55 mm in diameter) provided on a generator, and a driven pulley (150 mm in diameter) provided on an air compressor. A belt is hung on the pulley, a tension pulley (diameter: 85 mm) is brought into contact between a driven pulley provided on the generator and a driven pulley provided on the air compressor, and the tension pulley is adjusted to apply a 390N tension to the belt. Gave. The running conditions are as follows: the ambient temperature is room temperature, the rotation speed of the driving pulley is 1000 rpm, the angular velocity fluctuation is 1.0 deg, and the load of the driven pulley (55 mm in diameter) is 1.9 kw.

A sound test was performed using this driving device. The tension at which sound was generated by gradually lowering the tension was defined as the sound generation limit tension. Example 1 has 18N, Example 2 has 19N, and the conventional example has 21N. It can be seen that the V-ribbed belt of the present invention has lower sounding limit tension than the conventional one.

[0020]

[Effect of the invention]

 As described above, the present invention is a V-ribbed belt in which at least the rib height at both ends and the rib height at the central portion are different, so that the change in the rib angle when the belt is bent is the same as that at the ribs at both ends and the rib at the central portion. Therefore, there is an effect that a good contact state can be ensured for a wide range of pulley diameters.

[Brief description of the drawings]

FIG. 1 is a sectional perspective view of a V-ribbed belt according to the present invention.

FIG. 2 is a sectional perspective view of another V-ribbed belt according to the present invention.

FIG. 3 is a schematic view showing a driving device using the V-ribbed belt of the present invention.

FIG. 4 is a sectional perspective view of a conventional V-ribbed belt.

[Description of Signs] 1 V-ribbed belt 3 Cushion rubber layer 4 Rib 5 Upper cover cloth 7 Rib 9 V-ribbed belt 10 Multi-axis drive device 11 Face-to-face friction drive surface 12 Followed shaft 14 Followed shaft 16 Drive pulley 17 Followed pulley 18 Followed pulley

Claims (1)

[Utility model registration claims] 1. A V-ribbed belt having at least a plurality of ribs, wherein at least the rib height at both ends and the rib height at a central portion are different.