Patent ID: 6801304
Filing Date: 2004-10-05
Classification: B65H,G03G

Abstract:
An image forming apparatus comprising:a paper storage part for storing sheets of paper for use in copying; a weight detecting part for detecting a weight of sheets of paper stored in said paper storage part; a paper feed counting part for counting sheets of paper fed for copying from said paper storage part; a checking sheet number setting part for setting a number of sheets for checking as a predetermined number of sheets of paper used to check a predetermined parameter concerning sheets of paper; a weight calculating part for comparing weights of sheets of paper detected by said weight detecting part before and after said paper feed counting part counts a number of sheets of paper fed equal to said number of sheets for checking to detect a decrease in weight of the sheets of paper, and for calculating a weight per sheet of paper or per unit number of sheets of paper on a basis of the decrease in weight and said number of sheets for checking; a designating part for designating a number of copies to be made; a calculating part for calculating a number of remaining sheets of paper in said paper storage part on a basis of the weight per sheet of paper or per unit number of sheets of paper calculated by said weight calculating part and the weight of sheets of paper detected by said weight detecting part; a judging part for judging whether or not the number of remaining sheets of paper calculated by said calculating part is adequate for said number of copies to be made designated by said designating part on a basis of said number of remaining sheets of paper and said number of copies to be made; a memory part for storing a weight of standard paper, which is a weight per sheet of standard paper or per unit number of sheets of standard paper, and a calculating part for calculating a number of remaining sheets of paper stored in said paper storage part from said weight of sheets of paper detected by said weight detecting part and said weight of standard paper when a number of copies to be made is designated by said designating part at a time of starting.