BELT DRIVE MECHANISM, BELT DRIVE DEVICE, AND PULLEY

摘要

PROBLEM TO BE SOLVED: To prevent a belt 45 from meandering in a belt drive device 41 including a plurality of pulleys 50, and the belt 45 wound around the pulleys 50 and made of a metallic material.SOLUTION: On the outer circumferential face of at least one pulley 43 of a plurality of pulleys 50, bulge portions 51 bulging outward in a pulley radial direction are formed all over the circumference. The linear expansion coefficient of the bulge portions 51 in the pulley radial direction varies in a pulley width direction.