SURFACE STATE DETERMINATION DEVICE OF CONVEYING MEMBER, SHEET CONVEYING FORCE DETERMINATION DEVICE, SHEET CONVEYING DEVICE, AND IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a surface state determination device of a conveying member capable of correctly determining the timing for changing the conveying member by determining the conveying force of a sheet by the conveying member by correctly determining the surface state of the conveying member. SOLUTION: The surface state determination device of a drawing roller 24a for determining the surface state of the drawing roller 24a for conveying a sheet P while holding it comprises an irradiation device 81b for a conveying member for irradiating laser beam R on the surface of the drawing roller 24a, an image pickup device 82b for the conveying member for picking up an image of a second dot pattern formed on the irradiation surface of the surface of the drawing roller 24a by the laser beam R, and a second analysis means 90b for calculating the contrast ratio C and the image frequency F by analyzing the distribution of the light intensity In of the second dot pattern. The surface state of the drawing roller 24a is determined by comparing the contrast ratio C and the image frequency F with the threshold CLof the contrast ratio C and the threshold FLof the image frequency F. COPYRIGHT: (C)2010,JPO&INPIT