Abstract: A V-belt for high load transmission reduces the temporal change in belt tension according to a change in a thrust-tension conversion ratio from an initial running stage. For this purpose, the side surfaces of each tension band and blocks in a belt width direction form sliding surface abutting on the groove surface of a pulley. An area S1 of the sliding surface of the tension band and an area S2 of the sliding surface of each of the blocks satisfy a relationship of S1/S2?0.2 (i.e., the area S1 of the sliding surface of the tension band is 20% or smaller of the area S2 of the sliding surface of each of the blocks).

Abstract: A V-belt for high load transmission includes numbers of blocks engaged with and fixed to tension bands. Power is transmitted by meshing teeth of the blocks with grooves of the tension bands. A belt pitch width a being a width of each block at a position of a cord of each tension band, and a meshing thickness b of the tension band between bottoms of upper recesses and bottoms of lower recesses of the tension band satisfy a relationship of b/a?0.08. (That is, the meshing thickness b of each tension band is 8% or smaller of the belt pitch width a). The meshing thickness b of the tension band and a total thickness c of the tension band being a thickness of each of cogs, which are portions of the tension band other than the upper and lower recesses, satisfy a relationship of c/b?2.0.

Abstract: On each block side face of the blocks of a V-belt for transmitting high load, a ratio of a dimension extending in a belt thickness direction from a buried cord center line of a corresponding tension band to an upper end of an upper pulley-contact face to a dimension extending in the belt thickness direction from the buried cord center line to a lower end of the upper pulley-contact face is larger than or equal to 4.0, and a dimension extending in the belt thickness direction from the buried cord center line to a middle of the upper pulley-contact face is smaller than or equal to 2.3 mm.

Abstract: On each block side face of the blocks of a V-belt for transmitting high load, a ratio of a dimension extending in a belt thickness direction from a buried cord center line of a corresponding tension band to an upper end of an upper pulley-contact face to a dimension extending in the belt thickness direction from the buried cord center line to a lower end of the upper pulley-contact face is larger than or equal to 4.0, and a dimension extending in the belt thickness direction from the buried cord center line to a middle of the upper pulley-contact face is smaller than or equal to 2.3 mm.

Abstract: A high load transmission V-belt includes: an endless tension band; and a plurality of blocks arranged side by side in a longitudinal direction of the tension band and each engaged with the tension band. Each of the plurality of blocks has a reinforcing structure member comprised of carbon fibers, and a resin coating layer provided so as to coat the reinforcing structure member.

Abstract: On each block side face of the blocks of a V-belt for transmitting high load, a ratio of a dimension extending in a belt thickness direction from a buried cord center line of a corresponding tension band to an upper end of an upper pulley-contact face to a dimension extending in the belt thickness direction from the buried cord center line to a lower end of the upper pulley-contact face is larger than or equal to 4.0, and a dimension extending in the belt thickness direction from the buried cord center line to a middle of the upper pulley-contact face is smaller than or equal to 2.3 mm.

Abstract: In a high load transmission V-belt, a plurality of blocks 20 are attached and fixed to a tension band 10 extending in a belt length direction in a state in which each of the blocks 20 are arranged so as to sandwich an engagement section 18 of the tension band 10 in an inter-beam clearance portion 26 formed between upper and lower beam portions 23, 24. An increased amount of change ?T in dimension T of the engagement section 18 of the tension band 10 in a belt thickness direction due to thermal expansion is equal to or less than an amount of change ?G in dimension G of the inter-beam clearance portion 26 of the block 20 in the belt thickness direction while running the belt (?T??G).

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 high load transmission V-belt, a plurality of blocks 20 are attached and fixed to a tension band 10 extending in a belt length direction in a state in which each of the blocks 20 are arranged so as to sandwich an engagement section 18 of the tension band 10 in an inter-beam clearance portion 26 formed between upper and lower beam portions 23, 24. An increased amount of change ?T in dimension T of the engagement section 18 of the tension band 10 in a belt thickness direction due to thermal expansion is equal to or less than an amount of change ?G in dimension G of the inter-beam clearance portion 26 of the block 20 in the belt thickness direction while running the belt (?T??G).

Abstract: The present invention aims at improving the shock resistance of a block while reducing the noise of a belt running. 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 each of the plurality of blocks 20 includes a contact surface 30 to be in contact with a pulley on each of opposite end portions of the block 20 in a belt width direction, each of the plurality of blocks 20 includes a slope 31 formed so as to be continuous with a belt inner side of the contact surface 30 and inclined toward a center in the belt width direction with respect to the contact surface 30, and an angle of the slope 31 with respect to the contact surface 30 is 120 degrees or more and 140 degrees or less.

Abstract: A belt drive system including an assembly of a heavy-duty drive V-belt 5 and pulleys 2 and 4 reduces noise generating owing to belt travel while ensuring the durability of the pulleys 2 and 4. The surfaces of belt grooves 6 in the V-pulleys 2 and 4 are micro-blasted or burnished so that their surface roughness satisfies the relational expression y??0.9×tp+100, where tp is the load length rate at a given position of a roughness curve indicating the surface features of the groove surfaces in the V-pulleys 2 and 4 and y is the variable (the degree of height) indicating by percentage the ratio of the height from the lowest valley having a maximum depth to the given position to a maximum height Ry.

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 belt drive system including an assembly of a heavy-duty drive V-belt 5 and pulleys 2 and 4 reduces noise generating owing to belt travel while ensuring the durability of the pulleys 2 and 4. The surfaces of belt grooves 6 in the V-pulleys 2 and 4 are micro-blasted or burnished so that their surface roughness satisfies the relational expression y??0.9×tp+100, where tp is the load length rate at a given position of a roughness curve indicating the surface features of the groove surfaces in the V-pulleys 2 and 4 and y is the variable (the degree of height) indicating by percentage the ratio of the height from the lowest valley having a maximum depth to the given position to a maximum height Ry.

Abstract: In a belt continuously variable transmission constructed such that a block-type belt in which a plurality of blocks are fixedly engaged with a pair of tension members is wound between driving and driven pulleys of variable diameter each having a V-section pulley groove with a predetermined wedge angle &agr;, even if oil mist adheres to the surfaces of the pulley grooves and contact surfaces of the blocks, its transmission power is prevented from being reduced. This can be attained by setting the wedge angle &agr; at a value equal to or less than 20°. By increasing the apparent friction coefficient &mgr;′ between each pulley and each block of the belt, the transmission can retain a high transmission power, and concurrently the friction coefficient &mgr; between each pulley and each block can be reduced to the level to which the friction coefficient &mgr; is decreased due to oil-mist adhesion.

Abstract: In a belt transmission system including a combination of a V-belt for heavy load transmission and V-pulleys as variable speed pulleys, the surface roughness of a pulley groove of each V-pulley is set within the range from 0.5 to 3.0 &mgr;m to reduce energy generated when the V-belt and the V-pulleys are interfered with each other thereby reducing production of running noise during belt running.

Abstract: A heavy-duty power transmission V-belt includes right and left tension members having concave parts on upper and lower faces thereof, and a large number of blocks having fitting parts for compressedly fitting the tension members therein on right and left side faces of the blocks. By compressedly fitting the tension members in the fitting parts of the blocks, the respective blocks are fixedly engaged with the tension members so as to allow the side faces thereof to be brought into contact with a groove face of the pulley. An innermost lower face is formed in an innermost portion of the fitting part of each block, and an innermost lower face angle &agr; between the innermost lower face and a vertical plane is determined so as to have a relationship of &bgr;−3<&agr;<&bgr;+3 with a belt side face angle &bgr;.

Abstract: A heavy-duty power transmission V-belt is so designed that respective upward projections each having an arcuate cross section of respective blocks are fixedly engaged with respective bottom-surface grooves each having an arcuate cross section of a tension member. The radius of curvature R2 of each bottom-surface groove is set larger than the radius of curvature R1 of the upward projection of the block (R2>R1) in the state that the tension member is put strait. Thereby, when the V-belt bends around a pulley, it can be avoided that a large local strain occurs at the bottom-surface groove. This allows a firmly fixed state of each block by the tension member to be maintained for a long time.