| 摘要 |
PURPOSE:To decrease the number of parts of a device, and to make a developing device compact and inexpensive by constituting it so that two developer tanks are placed to one developing electrode, and developers in both the developer tanks are supplied selectively to an electrostatic latent image carrying body. CONSTITUTION:The titled device is provided with two developer tanks 4, 5 storing a developer, a developing sleeve 11, developer carrying and guiding means 7, 7' for carrying the developer, and thereafter, returning it to each developer tank 4, 5, and switching means 8, 8' for switching alternately carriage of the developer extending from the developer tanks 4, 5 to an electrostatic latent image carrying body 2 between two developers. In such a way, the carrying of the developer to the electrostatic latent image carrying body 2 is switched alternately as a time between two developers by the switching means 8, 8', therefore, it does not occur that the developers of two developer tanks 4, 5 are mixed, and a development is executed in a state that a contact of the developer to the electrostatic latent image carrying body 2 is secured by the carrying and guiding means 7, 7'. Accordingly, by using a mixture of a toner and a carrier electrified to the opposite polarity of positive and negative as two developers, bipolar copying of N-P and P-P can be executed, and by using developers of different colors, dichromatic copying can be executed. |
