SHEET LENGTH MEASUREMENT DEVICE, IMAGE FORMATION APPARATUS AND SHEET MATERIAL DETECTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a sheet length measurement device which can accurately measure the length of a sheet material.;SOLUTION: A sheet length measurement device 100 includes: a driven roller 31 which rotates by being in contact with a sheet P; a measurement mechanism which measures the rotation amount of the driven roller 31; and position detection mechanisms (CIS) which are respectively provided on the upstream side and downstream side of the driven roller 31 in the conveyance direction of the sheet P. The CISs 35, 36 have sensor element arrays where a plurality of sensor elements are arrayed, are arranged across side ends in the width direction, and arranged with an inclination with respect to the conveyance direction of the sheet P, and measure the sheet length L of the sheet P on the basis of the rotation amount of the driven roller 31 measured by the measurement mechanism and the end position of the sheet P detected by the CISs 35, 36.;SELECTED DRAWING: Figure 3;COPYRIGHT: (C)2017,JPO&INPIT