To suitably guide a conveyance body or a conveyed object conveyed in a curvilinear transfer part.

A plurality of conveyance bodies 20 are arranged per predetermined intervals on an endless belt 18 wound between a first conveyance pulley 14 and a second conveyance pulley 16 journalled to a machine casing 12. A first pulley 34 and a second pulley 36 are pivotally supported so as to horizontally rotate on the machine casing 12 at separated positions in front and rear of the first conveyance pulley 14, a third pulley 40 and a fourth pulley 42 are pivotally supported so as to horizontally rotate on the machine casing 12 at positions separated to the front and rear and outwardly separated from the curvilinear transfer part, and a round belt 32 is wound around the four pulleys 34, 36, 40, and 42. A portion of the round belt 32 tensionally provided between the first pulley 34 and the second pulley 36 contacts outside rims of both external walls 26 and 26 of a conveyance body 20 conveyed on the curvilinear transfer part and it faces them in a state stretched between both external walls 26 and 26.