JPH07238993A - Double v-ribbed belt - Google Patents

Abstract

PURPOSE:To prevent any longitudinal split in a V-rib groove bottom without entailing an increase in the total thickness of a belt by modifying the structure of a tension member layer of this V-ribbed belt. CONSTITUTION:In a double V-ribbed belt being made up of integrally setting up plural pieces of V-type ribs extending in the belt longitudinal direction over both vertical surfaces of a tension member layer 4 made up of spirally embedding a tension member rope 2 in an adhesive rubber layer 3 at the same pitch, two flat monofilaments 7 and 8 of each cross section whose value of the ratio of length to breadth is 1.5 to 10 are embedded in at least either side of the adhesive rubber layer 3 in space between both upper and down ribs 5 and 6 to be set up in an upper part and a lower part of the tension member layer 4 crosswise and parallelly in making the sectional breadth accord with the belt's height direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double V-ribbed belt, and more particularly to a belt tension body layer portion provided on both sides thereof with a group of ribs extending in the longitudinal direction of the belt. The present invention also relates to a double V-ribbed belt that is efficient and feasible at the same time.

[0002]

2. Description of the Related Art V-belts used for automobiles are
It is installed independently between the crank / alternator / fan, crank / power steering, crank / cooler, etc. Multiple V-belts are used in one vehicle.

Recently, there are demands from various directions such as saving the vehicle body space, reducing the weight of the vehicle body, and saving fuel consumption. Therefore, a V-shaped rib extending in the longitudinal direction of the belt is formed on the lower surface of the adhesive rubber layer in which the tensile body rope is embedded. There is provided a drive device in which a single V-ribbed belt in which the upper surface of the adhesive rubber layer is covered with 1 to 2 ply of rubberized canvas is suspended between a plurality of pulleys arranged at predetermined positions in a winding manner. Used (Figure 3).

A V-ribbed belt suspended on a driving pulley (Dr) used for this multi-axis driving device and driven pulleys (Dn1) (Dn3) and (Dn4) arranged for a predetermined purpose adjusts the belt tension. Since the rear idler pulley (Di) and the rear driven pulley (Dn2) arranged for a predetermined purpose are used for rear driving,
The back surface of the belt, which does not have a wedge effect, has lower transmission performance than the rib portion, and when the back surface of the belt and / or the rib surface wears and the belt tension drops, slippage occurs and power transmission under high load is not possible. There was a problem such as not being suitable.

In order to solve these problems of the conventional V-ribbed belt, as shown in an example of FIG. 4, the rib pitch, the rib height, the rib height, the rib pitch, and the rib are formed on the upper and lower surfaces of the adhesive rubber layer 33 in which the tensile body rope 32 is embedded. Double V connecting multiple V-shaped ribs 35 and 36 extending in the longitudinal direction of belts of the same shape
A ribbed belt 31 has been proposed, US Pat. No. 272823.
FIG. 4 of the specification of No. 9 also discloses a specific example of this double V-ribbed belt.

[0006]

By arranging a plurality of pulleys shown in FIG. 3 at predetermined positions and suspending the belt between these pulleys, by using the double V-ribbed belt 31 shown in FIG. Although power transmission of load is possible, this type of drive mechanism often causes vertical tearing at the rib groove bottom between the V-shaped ribs due to pebbles biting, misalignment, or the like.

Further, since the double V-ribbed belt of this kind attaches great importance to the flexibility, the gap between the bottoms of the upper and lower rib grooves is small and it is difficult to insert a vertical tear preventing material. However, it is necessary to thicken the adhesive rubber layer 3 when the vertical crack preventing material is added,
As a result, there is a problem that the total thickness of the belt is increased and the flexibility is reduced.

The present invention has been arrived at as a result of earnest studies to solve the above-mentioned problems of the conventional double V-ribbed belt, and the total thickness of the belt is reduced by partially modifying the structure of the tensile member layer. An object of the present invention is to provide a double V-ribbed belt capable of preventing vertical cracks occurring at the rib groove bottom between V-shaped ribs without increasing the thickness.

[0009]

In order to achieve the above object, the present invention is characterized in that a belt is provided on both upper and lower surfaces of a tensile strength layer in which a tensile strength rope is spirally embedded in an adhesive rubber layer. In a double V-ribbed belt in which a plurality of V-shaped ribs extending in the longitudinal direction are integrally arranged at the same pitch, a double V-ribbed belt is disposed between the upper and lower ribs of the tensile body layer and the tensile body rope. In at least one of the adhesive rubber layers, the monofilament having a flat cross section with a ratio of the major axis to the minor axis of 1.5 to 10 is in the lateral direction, and the minor axis of the cross section is in the height direction of the belt. Is a double V-ribbed belt that is embedded in parallel in line with. The minor diameter of the flat monofilament must be 0.8 mm or less.

[0010]

EXAMPLES Next, specific examples of the double V-ribbed belt according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a part of a double V-ribbed belt embodying the present invention.
The double V-ribbed belt 1 of the present invention is made of polyester, polyamide, aramid, carbon, glass fiber or the like as a raw material and has a low elongation and high strength tensile body rope 2, NR (natural rubber), SBR (styrene-butadiene rubber). , CR
(Chloroprene rubber), NBR (Nitrile rubber), HN
Single material such as BR (hydrogenated nitrile rubber), CSM (chlorosulphonated polyethylene rubber), polyurethane,
Alternatively, a tensile body layer 4 embedded in an adhesive rubber layer 3 made of a rubber-like elastic body in which these are appropriately blended is arranged at the center, and the adhesive rubber layer 3 is provided on both upper and lower surfaces of the tensile body layer 4. A plurality of V-shaped upper ribs 5 extending in the longitudinal direction of the belt, which are made of a rubber-like elastic material of the same material, and lower ribs 6 arranged at the lower portion.
It is the same as the conventional double V-ribbed belt in that it is configured more.

If necessary, synthetic fibers such as nylon, vinylon, polyester, aromatic polyamide, etc., or natural fiber yarns such as cotton, pulp, etc. may be added to the upper and lower ribs at a predetermined ratio to the synthetic fiber yarns. 3 to 10 mm of mixed yarn
The length of the rubber is oriented and mixed in the belt width direction at a ratio of 5 to 30 parts by weight with respect to 100 parts by weight of rubber.

In the present invention, in the adhesive rubber layer 3 between the tension rope 2 and the upper and lower ribs 5 and 6 in the tension layer 4, monofilaments 7 and 8 having a flat cross section are belted. A plurality of monofilaments 7 and 8 are embedded in parallel to each other in the lateral direction with the minor axis of the cross section of the monofilaments 7 and 8 aligned with the height direction of the belt 1 over the entire length of the belt. The flat shape of the monofilament is designed such that the ratio of major axis to minor axis is in the range of 1.5 to 10 and the minor axis length is 0.8 mm or less.

As the material for the monofilaments 7 and 8, it is desirable to use a synthetic resin such as nylon, polyester, vinylon or aramid, or a mixture thereof. As described above, by using the flat monofilament, it is possible to insert the vertical tear preventing material into the adhesive rubber layer 3 between the upper and lower ribs 5 and 6 and the tensile body rope 2, which is a small space. is there.

The reason why the ratio of the long diameter to the short diameter of the monofilament is limited to the range of 1.5 to 10 is that the ratio is 1.
When the length is 5 or less, the length of the minor axis becomes larger than 0.8 mm, and the thickness of the adhesive rubber layer 3 becomes thicker by that amount, and as a result, the thickness of the tensile body layer 4 becomes thicker and the flexibility of the belt decreases. On the other hand, when the ratio is 10 or more, the monofilaments become too flat and the spacing between the monofilaments becomes narrow, resulting in difficulty in bending the belt, which is offset by the effect of making the thickness thin and easy to bend, and the life cannot be improved. It will be possible.

FIG. 2 shows another embodiment of the present invention, which is a tensile body layer 4 '.
In this case, the flat monofilament 8 is inserted laterally with respect to the belt 1 in the adhesive rubber 3 between the tensile body rope 2 and the lower rib 6. As a matter of course, the embedding position of the flat monofilament may be in the adhesive rubber layer 3 between the tension rope 2 and the upper rib 5 of the tension layer 4 ′ on the side opposite to FIG. 2. Needless to say.

Experimental Example Next, the double V-ribbed belt 1'according to the present invention from which the lower monofilament of the double V-ribbed belt shown in FIG. 1 is removed, and the conventional double V-ribbed belt 31 shown in FIG.
Therefore, a specific experimental example in which the vertical tearing force is measured for confirming the effect will be described. The experimental method was to use a double V ribbed belt with four K-shaped ribs on the top and bottom, with a major axis of 1.65 mm.
Narrow monofilament having a flat cross section with a minor axis of 0.22 mm and a major axis to minor axis ratio of 7.5 is arranged in parallel on the upper side. Two rib peaks of the double V-ribbed belt embedded by the method were gripped by a chuck, and the vertical tearing force was compared by pulling at a pulling speed of 50 mm / min using a tensile tester with the bottom of the rib groove as a boundary.

As a result, the belt according to the present invention is 145-45.
153N (newton), the conventional belt is 52-62N
It was confirmed that the belt of the present invention had a vertical tear force of about 2.6 times that of the conventional belt.

[0018]

The double V-ribbed belt according to the present invention is
A flat monofilament is laterally disposed in the adhesive rubber layer of at least one of the upper and lower ribs disposed on the upper and lower portions of the tensile body layer and the tensile body rope, and the minor axis of the cross section of the ribbed belt is used. The following effects can be obtained by embedding them in parallel in the height direction.

1. By using a flat monofilament, it is possible to insert a vertical tear prevention material between the rib groove bottom, which is a small space, and the tension rope, and a sufficient vertical tear force can be obtained. 2. By arranging the flat monofilaments laterally in parallel with the tensile body layer in a constant space, the adhesive rubber can flow between the monofilaments, and a large decrease in adhesive strength can be prevented. 3. Since the bending property is also good, there is little concern about delamination between the tension layer and the V-ribs due to stress concentration during bending.

[Brief description of drawings]

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

FIG. 2 is a belt sectional view showing another embodiment according to the present invention.

FIG. 3 is a schematic front view of a multi-axis drive device showing one usage mode of a double V-ribbed belt.

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

[Explanation of symbols]

 1 Double V-ribbed belt 2 Tensile rope 3 Adhesive rubber layer 4 Tensile body layer 5 Upper rib 6 Lower rib 7 Flat monofilament 8 Flat monofilament

Claims (2)

[Claims] 1. A double structure in which a plurality of V-shaped ribs extending in the belt longitudinal direction are integrally arranged at the same pitch on the upper and lower surfaces of a tensile body layer in which a tensile body rope is spirally embedded in an adhesive rubber layer. In the V-ribbed belt, the value of the ratio of the major axis to the minor axis is 1 in at least one of the adhesive rubber layers disposed between the upper rib and the lower section of the tensile body layer and between the lower rib and the tensile body rope. A double V-ribbed belt, wherein monofilaments having a flat cross section of 0.5 to 10 are embedded in a lateral direction and in parallel with the minor axis of the cross section being aligned with the height direction of the belt. 2. The flat monofilament has a minor axis of 0.
The double V-ribbed belt according to claim 1, which is 8 mm or less.