To carry out the pitch conveyance efficiently by using a single driving means, even though parallel working stations and separate working stations are mixed.

A cylinder device is started, hooks are engaged to pallets at the stations other than the stations in a vacant condition, a pitch conveying is started, and the pallets are moved to following stations respectively. That is, the cylinder device is started, and only pallets D, E, F, and G at stations 5, 6, 7, and 8 are pitch conveyed. Specific workings are carried out to works, at the stations 2, 3, 4, and 10 and 11. Then, while the pallet J is delivered to the following process from the derivery station, a pallet from the former process is conveyed to the station 1. In this case, in the parallel working stations 6 an 7, the processing work of the works in the pallets D and E are carried out in parallel. And the pallets at the stations other than the parallel working stations are pitch conveyed.