A first roller is driven, by a conveying motor rotating in a normal direction and in a reverse direction, to rotate in a forward direction and in a backward direction, respectively. The first roller and a second roller convey a sheet in a conveying direction by rotating in the forward direction. The transmission unit transmits a driving force of the conveying motor to the second roller and includes a first rotary member. The transmission unit has such play that when the conveying motor is switched from rotation in a normal direction to rotation in a reverse direction, rotation of the second roller in a backward direction is delayed by a predetermined time period from rotation of the first roller in the backward direction. The predetermined time period is greater than a time period corresponding to one tooth of the first rotary member.