PURPOSE: To provide a collator capable of collecting and aligning the desired number of signatures to form a main block.

CONSTITUTION: A circulating housing device 7 having a number of housing sections 8 opened to the outside is constructed in such a manner that signatures 4 are inserted into the housing sections 8, and the signatures 4 are taken out as a main block 13 collecting and aligning the signatures 4 and carried by a carrier device 10 having a rear stopper 12, and the height of the stopper 12 is adjustable. The housing device 7 is constructed as a thin and oblong conveyor having a partition plate 8 inclined relative to a horizontal line and disposed vertically, and the housing sections 8 are arranged in parallel between the feeding section 5 and the transfer section 10 of the signatures 4. By the housing device 7, the signatures 4 are carried along a straight track between the feeding section 5 and the delivery section 10.