To accomplish simplification of a structure of a belt drive part for driving a conveying roller.
In the belt drive device, a pair of tension pulleys 23 for tensioning a flat belt for driving the conveying roller is approachably/leavably supported on a support plate 24 through a support shaft 31 respectively. The respective support shafts are constituted by a position restriction part 33 having a through hole 33a from one end side to the other end side; a slide part 34 slidably arranged in a penetration groove part 24a formed on the support plate in a longitudinal direction; a shaft part 36 externally fitted with a bearing member 35 of the tension pulley; and a female screw part 37. At mounting of the pulley, the bearing member of the tension pulley is attached to the shaft part in the state that the slide part is arranged in the penetrated groove part of the support plate and its inner ring part 35a is fixed to the support plate side by fastening of a nut 39. The distance between the pair of tension pulleys can be adjusted by a pair of nuts thread-engaged with a hexagonal bolt inserted into the through hole of the respective position restriction part.
Yoshihiro Morimoto
Toshiji Sasahara
Yohei Harada