| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an image forming apparatus configured so that two factors of the concentration change and deterioration degree of a developer are sensed by using one detection means. <P>SOLUTION: The image forming apparatus includes an image carrier 1, a latent image forming device 2, a developing device 3 including a developer carrier 4 carrying a two-component developer (developer) G and a stirring and conveying member 5 which stirs and conveys the developer G before being carried by the developer carrier 4 and in which a spiral blade 5a is formed on the circumference of a rotation shaft member, a toner supply device 6 supplying toner, concentration detecting image forming means 7 forming a concentration detecting image IM, detection means 8 detecting the density of the concentration detecting image IM, supply control means 9 controlling the supply of the toner from the toner supply device 6 based on the detection result by the detection means 8, and developer deterioration degree discrimination means 10 determining whether or not concentration unevenness corresponding to the pitch of the spiral blade 5a of the stirring and conveying member 5 is present based on the detection result by the detection means 8, to discriminate the degree of the deterioration of the developer G according to the presence or absence of the concentration unevenness. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
