A power transmission belt includes a stacked body including a back surface layer disposed on a back surface side, an inner surface layer disposed on an inner surface side, and a tension member layer containing a tension member embedded between the back surface layer and the inner surface layer, in which the power transmission belt includes a sensor configured to detect a status of the power transmission belt, as at least a part of the stacked body.

A center cord-line V-belt with a radially centered cord line of helically wound tensile cord embedded in a very high-modulus adhesion gum, an overcord layer, and an undercord layer. The adhesion gum has a substantially isotropic modulus, while the overcord and undercord layers have anisotropy in with-grain and cross-grain moduli. The overcord and undercord cross-grain moduli are less than the adhesion gum modulus. The anisotropic moduli are the result of oriented short fibers and the with-grain modulus is oriented axially in the belt. The adhesion gum preferably has no short fiber. The belt preferably has no reinforcing fabric layer and no fabric wrap. The adhesion gum, overcord layer and undercord layer are preferably based on an ethylene-alpha-olefin elastomer, with peroxide cure, reinforcing filler, and metal salt of an α-β-unsaturated organic acid. The belt may have notches on one or both of the inner and outer radial surfaces for additional flexibility.

A frictional power transmission belt includes a tension layer forming a belt back surface, a compression rubber layer to be in contact with a pulley and frictionally engaged with the pulley, and a tension member embedded between the tension layer and the compression rubber layer along a belt length direction. The compression rubber layer has a surface to be in contact with the pulley. At least a part of the surface is coated with a fiber layer via a fiber/resin mixture layer. The fiber/resin mixture layer contains a resin component and heat-resistant fibers having a softening point or a melting point higher than a vulcanization temperature of a rubber forming the compression rubber layer. The fiber layer contains hydrophilic heat-resistant fibers having a softening point or a melting point higher than the vulcanization temperature and does not contain a resin component.

A frictional power transmission belt is provided, 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 frictional power transmission belt is provided, 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 V-ribbed belt has a plurality of V-rib portions extending along a longitudinal direction of the belt and in parallel with one another. The V-ribbed belt includes a compression rubber layer including a frictional power transmission face at least a part of which is configured to come in contact with a V-rib groove portion of pulleys. The frictional power transmission face of the compression rubber layer is formed from a vulcanizate of a rubber composition containing a rubber component and a noise suppression improver. A V-rib angle of the V-rib portions is larger than a V-rib groove angle of the pulleys by 5° to 9°.

A V-ribbed belt has a plurality of V-rib portions extending along a longitudinal direction of the belt and in parallel with one another. The V-ribbed belt includes a compression rubber layer including a frictional power transmission face at least a part of which is configured to come in contact with a V-rib groove portion of pulleys. The frictional power transmission face of the compression rubber layer is formed from a vulcanizate of a rubber composition containing a rubber component and a noise suppression improver. A V-rib angle of the V-rib portions is larger than a V-rib groove angle of the pulleys by 5° to 9°.

Methods of manufacturing a belt include laying up a first elastomeric layer of a belt build on a mandrel, laying up a tensile reinforcement layer on the first elastomeric layer, where the tensile reinforcement layer contains cords coated with a water based urethane compound, and laying up a second elastomeric layer on the first elastomeric layer and the tensile reinforcement layer. The belt build may be cured in a profile-forming mold, and afterward, cut to a predetermined belt width and/or length.

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 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.