Abstract: A flat belt includes a tension-resistant layer, in which a core cord is spirally wound, an upper holding rubber layer, a lower holding rubber layer, an upper rubber layer, and a lower rubber layer. The holding rubber layers and are laid on the upper and lower sides of the tension-resistant layer respectively, retaining the layer. The upper and lower rubber layers and are laid on the upper side of the upper holding rubber layer and the lower side of the lower holding rubber layer respectively. 150-300 parts by weight of ferrite for 100 parts by weight of rubber matrix are mixed in the upper rubber layer, which is on the outer peripheral side of the flat belt when the belt is wound on a guide wheel.

Abstract: The present invention aims at improving the shock resistance of a block without lowering the power transmission property or the wear resistance of a belt while suppressing the separation of the contact portion off of the reinforcing member. A high-load drive V-belt B includes: at least one tension band 10 extending in an endless loop; and a plurality of blocks 20 engaged and secured to the tension band 10 at a predetermined pitch in a belt length direction of the tension band 10, wherein the plurality of blocks 20 are each formed by a reinforcing member 27 and a resin on both sides of the reinforcing member 27 in a belt width direction, and each include a contact portion 28 having a contact surface 30 to be in contact with a pulley, and a thickness w of the contact portion 28 in a direction perpendicular to the contact surface 30 is set to 1.0 mm or more and 1.8 mm or less.

Abstract: A flat belt includes an adhesive rubber layer formed in an endless ring shape and having a tensile member embedded therein, a first rubber layer provided on a surface of the adhesive rubber layer, and a second rubber layer provided on the other surface of the adhesive rubber layer, in which an elastic modulus in a belt width direction of the adhesive rubber layer is higher than the elastic modulus in the belt width direction of each of the first rubber layer and the second rubber layer.

Abstract: [Problem] In a clutch mechanism using magnetic force, the problem is to avoid early damage to the rubber layer in contact with a rotating member without impairing the power transmission interrupting function of the mechanism. [Solving Means] A flat belt includes a tension-resistant layer 2, in which a core cord 2a is spirally wound, an upper holding rubber layer 3, a lower holding rubber layer 4, an upper rubber layer 5, and a lower rubber layer 6. The holding rubber layers 3 and 4 are laid on the upper and lower sides of the tension-resistant layer 2 respectively, retaining the layer 2. The upper and lower rubber layers 5 and 6 are laid on the upper side of the upper holding rubber layer 3 and the lower side of the lower holding rubber layer 4 respectively. 150-300 parts by weight of ferrite for 100 parts by weight of rubber matrix are mixed in the upper rubber layer 5, which is on the outer peripheral side of the flat belt when the belt is wound on a guide wheel.

Abstract: The present invention aims at improving the shock resistance of a block without lowering the power transmission property or the wear resistance of a belt while suppressing the separation of the contact portion off of the reinforcing member. A high-load drive V-belt B includes: at least one tension band 10 extending in an endless loop; and a plurality of blocks 20 engaged and secured to the tension band 10 at a predetermined pitch in a belt length direction of the tension band 10, wherein the plurality of blocks 20 are each formed by a reinforcing member 27 and a resin on both sides of the reinforcing member 27 in a belt width direction, and each include a contact portion 28 having a contact surface 30 to be in contact with a pulley, and a thickness w of the contact portion 28 in a direction perpendicular to the contact surface 30 is set to 1.0 mm or more and 1.8 mm or less.

Abstract: In a heavy duty power transmission V-belt B formed by engaging tension members 1 and 1 with a plurality of blocks 10, 10, . . . , to prevent as much as possible each block 10 from producing failure at the high-speed running of the belt, a fitting part 12 of each block 10 has an indent 22 formed by upwardly recessing a portion of a resin part 17 located between an upper ridge 14 and an innermost abutment surface 20 of the fitting part 12. Thereby, no edge exists between the innermost abutment surface 20 and the upper ridge 14 so that stress can be distributed. This prevents the occurrence of a crack in the resin part 17 due to stress concentration on the edge, the occurrence of a crack in a reinforcement 18 of each block 10 beginning at the leading end of the crack in the resin part 17, and in turn the fracture of an upper beam 18a of the reinforcement 18, thereby providing enhanced resistance against failure of the block 10.

Abstract: In a heavy duty power transmission V-belt B formed by engaging tension members 1 and 1 with a plurality of blocks 10, 10, . . . , to prevent as much as possible each block 10 from producing failure at the high-speed running of the belt, a fitting part 12 of each block 10 has an indent 22 formed by upwardly recessing a portion of a resin part 17 located between an upper ridge 14 and an innermost abutment surface 20 of the fitting part 12. Thereby, no edge exists between the innermost abutment surface 20 and the upper ridge 14 so that stress can be distributed. This prevents the occurrence of a crack in the resin part 17 due to stress concentration on the edge, the occurrence of a crack in a reinforcement 18 of each block 10 beginning at the leading end of the crack in the resin part 17, and in turn the fracture of an upper beam 18a of the reinforcement 18, thereby providing enhanced resistance against failure of the block 10.

Abstract: A V belt for high load transmitting having at least one endless load carrier and a plurality of blocks engaged with the load carrier in the lengthwise direction of belt. The center of gravity of the block is situated near the tensile members of the load carrier. The block, in the straight running state, is so supported that it is substantially perpendicular to the load carrier. Also, the block has the surface of arcuate shape in cross section at least at a part of its side surface.

Abstract: A V belt for high load transmitting having at least one endless load carrier and a plurality of blocks engaged with the load carrier in the lengthwise direction of belt. The center of gravity of the block is situated near the tensile members of the load carrier. The block, in the straight running state, is so supported that it is substantially perpendicular to the load carrier. Also, the block has the surface of arcuate shape in cross section at least at a part of its side surface.