Abstract: A thrust roller bearing includes a plurality of radially arranged rollers, and a pair of annular washers having raceway surfaces on which the rollers roll. The raceway surfaces are arranged to face each other. The roller is made of high-carbon chromium bearing steel and has a surface roughness of 0.01 to 0.10 in terms of Rvk and 0.01 to 0.08 in terms of Rk. At least one of the washers is made of carbon steel, surface compressive residual stress of the raceway surface is ?1400 MPa to ?1000 MPa, and Vickers hardness of surface of the raceway surface is 850 to 900.

Abstract: A thrust roller bearing includes a plurality of radially arranged rollers, and a pair of annular washers having raceway surfaces on which the rollers roll, the raceway surfaces being arranged to face each other. The roller is made of high-carbon chromium bearing steel, and contains 1.1 mass % to 1.6 mass % of carbon and 0.1 mass % to 0.6 mass % of nitrogen in a range of 0.1 mm from a surface. A surface compressive residual stress is smaller than ?900 MPa, a surface roughness is 0.01 to 0.10 in terms of Rvk and 0.01 to 0.08 in terms of Rk, and a Vickers hardness of the surface is 860 to 980. At least one of the washers is made of carbon steel, and surface roughnesses of the raceway surfaces are 0.05 to 0.20 in terms of Rvk and 0.08 to 0.15 in terms of Rk.

Abstract: A thrust roller bearing includes a plurality of radially arranged rollers, and a pair of annular washers having raceway surfaces on which the rollers roll. The raceway surfaces are arranged to face each other. The roller is made of high-carbon chromium bearing steel and has a surface roughness of 0.01 to 0.10 in terms of Rvk and 0.01 to 0.08 in terms of Rk. At least one of the washers is made of carbon steel, surface compressive residual stress of the raceway surface is ?1400 MPa to ?1000 MPa, and Vickers hardness of surface of the raceway surface is 850 to 900.

Abstract: A thrust roller bearing includes a plurality of radially arranged rollers, and a pair of annular washers having raceway surfaces on which the rollers roll, the raceway surfaces being arranged to face each other. The roller is made of high-carbon chromium bearing steel, and contains 1.1 mass % to 1.6 mass % of carbon and 0.1 mass % to 0.6 mass % of nitrogen in a range of 0.1 mm from a surface. A surface compressive residual stress is smaller than ?900 MPa, a surface roughness is 0.01 to 0.10 in terms of Rvk and 0.01 to 0.08 in terms of Rk, and a Vickers hardness of the surface is 860 to 980. At least one of the washers is made of carbon steel, and surface roughnesses of the raceway surfaces are 0.05 to 0.20 in terms of Rvk and 0.08 to 0.15 in terms of Rk.

Abstract: When a chain is wound around a pulley, a pin-pulley contact point as a contact point of a pin of the chain with the pulley slides and moves on a conical surface of the pulley. A contact point slip distance, namely the distance by which the pin-pulley contact point moves on the conical surface at this time, is associated with an offset. The offset is the distance between a pin-pin contact point, which is a contact point between the pins at the time the chain is in a linear state, and the pin-pulley contact point in a y-axis direction. Offsets that minimize the contact point slip distance at the maximum running radius and the minimum running radius of the chain are obtained, and the offset is set between these values. The pin-pulley contact point is set close to the pin-pin contact point of the chain in the linear state.

Abstract: Adjacent chain elements transmit a tension by allowing two pins to contact each other. When a chain which has been in a linear state starts to bend, a contact point moves from one point to another. Such movement of the contact point generates a force couple. This force couple causes the rear end of the chain element to move in a lifted manner. An increasing rate of this amount of movement with respect to a relative angle to an adjacent chain element is set such that the increasing rate is small when the relative angle is small, and becomes larger when the relative angle becomes larger.

Abstract: When a chain is wound around a pulley, a pin-pulley contact point as a contact point of a pin of the chain with the pulley slides and moves on a conical surface of the pulley. A contact point slip distance, namely the distance by which the pin-pulley contact point moves on the conical surface at this time, is associated with an offset. The offset is the distance between a pin-pin contact point, which is a contact point between the pins at the time the chain is in a linear state, and the pin-pulley contact point in a y-axis direction. Offsets that minimize the contact point slip distance at the maximum running radius and the minimum running radius of the chain are obtained, and the offset is set between these values. The pin-pulley contact point is set close to the pin-pin contact point of the chain in the linear state.

Abstract: Portions of a pair of first pin members, a pair of second pin members, and a pair of third pin members other than one end portions thereof are respectively inserted into and held in a pair of first holding holes, a pair of second holding holes and a pair of third holding holes that extend perpendicularly to reference surfaces that are top faces of first to third connected body assembly jigs. In this state, a single first link plate, a single second link plate and a third link plate are press-fitted onto the one end portions until the first to third link plates come into contact with the reference surfaces. In this way, first to third multiple connected bodies are assembled. Then, the first to third multiple connected bodies and multiple fourth link plates are assembled into a power transmission chain.

Abstract: Portions of a pair of first pin members, a pair of second pin members, and a pair of third pin members other than one end portions thereof are respectively inserted into and held in a pair of first holding holes, a pair of second holding holes and a pair of third holding holes that extend perpendicularly to reference surfaces that are top faces of first to third connected body assembly jigs. In this state, a single first link plate, a single second link plate and a third link plate are press-fitted onto the one end portions until the first to third link plates come into contact with the reference surfaces. In this way, first to third multiple connected bodies are assembled. Then, the first to third multiple connected bodies and multiple fourth link plates are assembled into a power transmission chain.

Abstract: Adjacent chain elements transmit a tension by allowing two pins to contact each other. When a chain which has been in a linear state starts to bend, a contact point moves from one point to another. Such movement of the contact point generates a force couple. This force couple causes the rear end of the chain element to move in a lifted manner. An increasing rate of this amount of movement with respect to a relative angle to an adjacent chain element is set such that the increasing rate is small when the relative angle is small, and becomes larger when the relative angle becomes larger.