Conveyor and manufacture method thereof

The present invention provides a method of manufacturing a conveyor, is possible by forming the flexible roll forming, the constraint can be carried out only from the outside does not occur and the inner surface of the torsional buckling wrinkles and bending, and thus have a high shape can be lightened precision conveyor orbit recessed curved portion. Orbit curved portion is constituted by a stepped short and long sides of the at least one side of a stepped hollow structure orbit (5C), thereby achieving weight reduction conveyor. An opening portion provided in the wall portion of the hollow structure (17), by means of bolts (22) the opening (17) at appropriate intervals through the frame mounting (21). The orbit of the step for making a hollow structure having a curved portion of the roll used to make inhibition deformed shape by the bending stress generated in the corner portion of the step due to concentration of the orbit.