A wrapped V-belt includes: a belt main body containing a compression layer containing a compression rubber layer and a fabric-laminated body layer a tension rubber layer and a tension member buried between the compression layer and the tension rubber layer; and an outside cloth that covers a periphery of the belt main body, in which the compression layer has a plurality of notch portions not covered with the outside cloth, and the notch portion has a top disposed in the fabric-laminated body layer.

The present invention relates to a frictional power transmission belt containing a compression layer having a power transmission surface, at least a part of which is capable of coming into contact with a pulley, in which the compression layer contains a polymer component and a polyvinyl alcohol-based resin.

The present invention pertains to a method for manufacturing a cogged V-belt having a plurality of cogs, the method containing: an unvulcanized sleeve formation step of forming an unvulcanized sleeve by laminating a plurality of unvulcanized rubber sheets that contain at least an unvulcanized rubber sheet for a compression rubber layer and an unvulcanized rubber sheet for a tension rubber layer; a vulcanized sleeve formation step of forming a vulcanized sleeve by vulcanizing the unvulcanized sleeve; and a cog formation step of forming the plurality of cogs on the compression rubber layer after the vulcanized sleeve forming step.

Provided is a frictional power transmission belt containing an adhesion rubber layer in contact with at least a portion of a tension member extending in a longitudinal direction of the belt, in which the adhesion rubber layer is formed of a first vulcanized rubber composition containing a rubber component and a filler. The filler contains substantially no silica and contains 30 parts by mass or more of carbon black based on 100 parts by mass of the rubber component, and the tension member has, on a surface thereof, an overcoat layer formed of a second vulcanized rubber composition containing a rubber component and silica.

A high efficiency belt having reduced bending stiffness while maintaining a high coefficient of friction. The belt includes a backing layer, a rib material layer, and cords embedded within, wherein the coefficient of friction of the high efficiency belt is greater than or equal to 0.03 mm/N times the bending stiffness for belts having a thickness in the range of from 2.6 mm to 4.2 mm. The belt can include a bending stiffness in the range of from about 30 N/mm to about 65 N/mm and an anisotropic modulus of elasticity ratio of between 1.1 and 5.0. Methods of manufacturing the high efficiency belt are also described and can include forming sheets of rib material with parallel aligned reinforcement fibers transverse to the direction of rotation of the high efficiency belt.

The present invention relates to a wrapped V-belt containing: a belt main body containing a compression layer containing a compression rubber layer and a fabric-laminated body layer, a tension rubber layer and a tension member buried between the compression layer and the tension rubber layer; and an outside cloth that covers a periphery of the belt main body, in which the compression layer has a plurality of notch portions not covered with the outside cloth, and the notch portion has a top disposed in the fabric-laminated body layer.

Methods of manufacturing a belt include, at least, laying up a plurality of cords of a belt build on a mandrel, laying up a tape adhesive on an inner surface of the plurality of cords, laying up a cushion layer on an opposing side of the tape adhesive, and vulcanizing the belt build in a profile-forming mold, where the tape adhesive is a vulcanizable rubber which is devoid carbon black. The methods may further include laying up an outer tape adhesive before the laying up of the plurality of cords, and in some aspects, tension layer is laid up before laying up the outer tape adhesive. In some other methods, the tension layer is laid up before the laying up of the plurality of cords. The methods may further include partially or fully wrapping the belt with a belt wrap prior to vulcanizing the belt.

A friction transmission belt includes short fibers arranged so as to protrude from a surface of a pulley contact-side part made of a rubber composition. The short fibers consist of aramid short fibers and non-aramid synthetic short fibers having a standard moisture regain of equal to or less than 4%.