Patent ID: 7870935

Claim:
A traction drive power transmission device comprising: at least one driving roller; a driven roller; a cylindrical shaft, wherein the shaft is held between the driving roller and the driven roller and rotational force of the driving roller is transmitted to the shaft by rotating the driving roller so as to move the shaft in an axial direction, and wherein a section, perpendicular to the axial direction of the shaft, of a face of said driving roller facing said shaft is in a shape of a line composed of a plurality of arcs, said driving roller being in contact with the surface of said shaft at a midpoint of each of said arcs, and a section, perpendicular to the axial direction of the shaft, of a face of said driven roller facing said shaft is in a shape of a line composed of a single arc; and a lubricator having applicators which apply lubricant only to portions of the shaft that are contacted by the driving roller and the driven roller, wherein said lubricator has an opening which is formed in a side of said lubricator to open both in the axial direction of said shaft and in a direction perpendicular to said axial direction, and said opening has such a width in the direction perpendicular to said axial direction as to enable said shaft to be inserted into and removed from said opening in the direction perpendicular to said axial direction without being interfered.