An accumulating apparatus for accumulating continuous sheet supplied from an upstream apparatus while continuously feeding said continuous sheet to a downstream apparatus, comprising: upper rollers each of which is parallel with a horizontal direction; lower rollers each of which is parallel with a horizontal direction; an upper arm and a lower arm; and a distance changing mechanism for simultaneously moving said upper arm and said lower arm opposite to each other with respect to a vertical direction to change a distance between said upper arm and said lower arm, wherein said upper rollers are arranged along an arm main body of said upper arm, said lower rollers are arranged along an arm main body of said lower arm, said continuous sheet is held in contact with said upper rollers and said lower rollers alternately to repeatedly travel between said upper arm and said lower arm, said distance changing mechanism comprises: a motion transmitting mechanism (60, 60a, 60b) mechanically coupling said upper arm with said lower arm to synchronize movement of said upper arm with movement of said lower arm; and an actuator for performing at least one of an action to move said upper arm and said lower arm away from each other and an action to move said upper arm and said lower arm close to each other, and characterised in that said motion transmitting mechanism is a plurality of gears comprising: an upper gear fixed to said upper arm; and a lower gear fixed to said lower arm and engaged with said upper gear; and said upper arm and said lower arm are swung up and down. upper rollers each of which is parallel with a horizontal direction; lower rollers each of which is parallel with a horizontal direction; an upper arm and a lower arm; and a distance changing mechanism for simultaneously moving said upper arm and said lower arm opposite to each other with respect to a vertical direction to change a distance between said upper arm and said lower arm, wherein said upper rollers are arranged along an arm main body of said upper arm, said lower rollers are arranged along an arm main body of said lower arm, said continuous sheet is held in contact with said upper rollers and said lower rollers alternately to repeatedly travel between said upper arm and said lower arm, said distance changing mechanism comprises: a motion transmitting mechanism (60, 60a, 60b) mechanically coupling said upper arm with said lower arm to synchronize movement of said upper arm with movement of said lower arm; and an actuator for performing at least one of an action to move said upper arm and said lower arm away from each other and an action to move said upper arm and said lower arm close to each other, and a motion transmitting mechanism (60, 60a, 60b) mechanically coupling said upper arm with said lower arm to synchronize movement of said upper arm with movement of said lower arm; and an actuator for performing at least one of an action to move said upper arm and said lower arm away from each other and an action to move said upper arm and said lower arm close to each other, and characterised in that said motion transmitting mechanism is a plurality of gears comprising: an upper gear fixed to said upper arm; and a lower gear fixed to said lower arm and engaged with said upper gear; and said upper arm and said lower arm are swung up and down. an upper gear fixed to said upper arm; and a lower gear fixed to said lower arm and engaged with said upper gear; and said upper arm and said lower arm are swung up and down.