PURPOSE: To enable widening of a distance between bins and reduce the size of a sorter, by vertically movably mounting each bin and providing a pair of two vertically movable bin supporting devices which support the bin at the adjacent stage below a bin intending to house sheets and the bin at the adjacent stage above said bin intending to house sheets.

CONSTITUTION: A sorter, into which sheets are fed through a sheet conveying guide 2, is constituted such that bins 7 are located in a multistage, and in which case, in order to widen a distance between the bins 7 so as to match the position of a vertically movable indexer 4, ratchet blocks 8 and 9 are used as a pair of two bin supporting devices. The block 8 raises the bin 7, located at the adjacent stage above the bin 7 intending to house sheets, to a level higher than that of the normal stationary position, and the block 9 operates so that it causes a subsequent bin at the adjacent stage therebelow to wait below the bin intending to house the sheets. The blocks 8 and 9 are coupled to endless wires 10 and 11 rotationally moved through running of motors 16 and 17, moved vertically along rails 22 and 23, and are provided with ratchets 24 and 25 swung by solenoides 28 and 29.