| 摘要 |
PURPOSE: To prevent local concn. reduction of toner by the increase of the additive concn. CONSTITUTION: Inside a main body case 21, a magnetic roller 4 for attracting and transporting the toner is provided, feeding ports are disposed at both end parts of the main body case 21 in the lower part of the magnetic roller 4, and a recovering port 24 is disposed in the center part. Moreover, the toner cartridge 20 provided with such a constitution that a blade 22 is held in contact with a center part of a magnetic roller 4 and tips of ribs 23 are arranged close to the both end parts, is attached to a developing part 25, and the supply port confronts the feed-in port and the recovery port 24 confronts the delivery port 27. Then, at the time of performing a developing operation, fresh toner is fed from both end sides of the toner cartridge 20 to the developing unit 25, a part of the toner in the developing unit 25 enters the recovery port 24 from the delivery port 27 by rotation of an agitation unit 9, the toner is attracted and transported by the magnetic roller 4, and moreover the toner is scraped off by the blade 22, thus the toner is circulated between the developing unit 25 and the cartridge 20. |
