V-belt for high load transmission

摘要

A V-belt B for high load transmission is composed of endless load carriers 1, 1 and a large number of blocks 5, 5, ... . In the middle of a centre pillar 8 on one side surface in a belt-lengthwise direction of each block 5, a concave 18 is formed. On the other side surface of each block 5, a convex 19 is formed so as to be capable of fitting the concave 18 of the adjacent block 5 therein. The concave 18 and the convex 19 are formed only in a resin material layer 13 and in the shape of a truncated half sphere. At a part of the top surface of the convex 19 from a pitch line 22 toward a belt inner face, an inclined surface 20 is provided which inclines so that an amount of projection of the convex 19 from the surrounding of the convex 19 is decreased toward the belt inner face. Thereby, even when the thickness of the resin material layer 13 of each block 5 in the belt-lengthwise direction is decreased by a reinforcing member 16 embedded in each block 5, the strength of the convex 19 is ensured while preventing decrease in strength of the centre pillar 8, which improves silentness and durability of the V-belt B. Further, on right and left side ends of each block 5, projections 17, 17 are provided which each extend in a direction orthogonal to the corresponding groove surface 20a of a pulley and each have an approximately uniform length along a radius of the pulley and parallel to the corresponding groove surface 20a, so that contact surfaces 11 are formed at top ends of the projections 17, respectively. Thereby, even when each contact surface 11 is worn out, a circumferential speed difference between each block 5 and the corresponding groove surface 20a of the pulley 20 when the block enters and exits from the pulley 20 is kept constant. As a result, changes over time of belt characteristics such as a belt sound, heat production and thrust balance are minimised.