Abstract: A continuously-variable-ratio transmission belt includes a beltlike continuity element having a body made of elastomeric material and in turn having inner teeth and outer teeth and a number of threadlike longitudinal inserts embedded inside the body; and a number of separate friction blocks which are made of plastic material, are co-molded onto the continuity element so as to each incorporate one tooth of the inner teeth and one tooth of the outer teeth, and are each defined by two lateral surfaces converging inwards of the belt and cooperating with respective sides of a groove of a trapezoidal-grooved pulley.

Abstract: A continuously-variable-ratio transmission belt includes a beltlike continuity element having a body made of elastomeric material and in turn having inner teeth and outer teeth and a number of threadlike longitudinal inserts embedded inside the body; and a number of separate friction blocks which are made of plastic material, are co-molded onto the continuity element so as to each incorporate one tooth of the inner teeth and one tooth of the outer teeth, and are each defined by two lateral surfaces converging inwards of the belt and cooperating with respective sides of a groove of a trapezoidal-grooved pulley.

Abstract: A tensioner for belts including a stationary structure (3), an arm (4) movable with respect to a shaft (7) of the stationary structure, a torsion spring (6), a pair of dampening cones (8), (9) associated with the stationary structure and the arm, a compression spring (10) acting on the dampening cones. The mean radius of the cones is smaller than the maximum radial dimension of the torsion spring. The value "1" of the arm is correlated to the mean radius of the cones determining a frictional dampening between the cones smaller than that existing between the shaft and the rotating arm.