Abstract: In a rectilinear motion driving apparatus, a shaft is fitted into a cylindrical body in a coaxial state, and a plurality of cylindrical coil rollers are interposed between the cylindrical body and the shaft by press fit so as to roll at a predetermined inclined angle to the axial direction. These cylindrical coil rollers are contacted with an outer peripheral surface of the shaft and an inner peripheral surface of the cylindrical body with a pressure contact force, and the cylindrical body or the shaft is rotated so that the shaft or the cylindrical body makes a rectilinear motion toward an axial direction. A pressure contact force of both inner and outer surfaces of the cylindrical coil roller to the cylindrical body and the shaft is set either higher or lower in the vicinity of the end portion thereof than the intermediate portion of the cylindrical body.

Abstract: In a rectilinear motion driving apparatus, a shaft (6) is fitted into a cylindrical body (4) in a coaxial state, and a plurality of cylindrical coil rollers (3a) is interposed between the cylindrical body and the shaft by press fit so as to roll at a predetermined inclined angle to the axial direction. Further, these cylindrical coil rollers (3a) are contacted with an outer peripheral surface of the shaft and an inner peripheral surface of the cylindrical body with a pressure contact force, and the cylindrical body or the shaft is rotated so that the shaft or the cylindrical body makes a rectilinear motion toward an axial direction. A pressure contact force of both inner and outer surfaces of the cylindrical coil roller (3a) to the cylindrical body (4) and the shaft (6) is set higher than an intermediate portion of the cylindrical body (4) in the vicinity of the end portion thereof, or is set lower than the intermediate portion of the cylindrical body (4) in the vicinity of the end portion thereof.