| 摘要 |
PROBLEM TO BE SOLVED: To obtain an electrophotographic device using plural-component developer, which is provided with a toner mixing and stirring device having a spiral projection on the outer periphery of an outside mixer and a sponge scraper provided by cutting the center part of the spiral projection, and a sensor for measuring the permeability of mixed and stirred toner in order to keep toner concentration constant in the device, and where the toner concentration is decided according to the lowering of output caused by scraping out the toner on the surface of a magnetic sensor by a scraper and toner detection output succeeding thereafter, and to eliminate trouble on the occurrence of a phenomenon that stirring performance is lowered and an excellent result is not obtained because the sponge scraper provided in the center part of the mixing and stirring device and the cut part of the spiral projection hinder the flow of the toner in an axial direction in the device. SOLUTION: By disusing the sponge scraper and the cut part of the spiral projection, providing the scraper having spiral projection shape and made higher than the spiral projection instead and providing the spiral projection all over the periphery of the outside mixer, the surface of the sensor is wiped out without hindering the flow of the toner in the axial direction. |
