| 摘要 |
PURPOSE:To prevent exactly the leakage of a magnetic toner without breaking a magnetic latent image by providing a toner leakage preventing mechanism for generating an unequal electric field in the vicinity of an inlet and outlet through which a magnetic latent image goes in and out. CONSTITUTION:Pickup rolls 11, 12 for catching a floating magnetic toner are provided between the first and the second openings of outside and inside housings 2a, 2b, respectively. As for the pickup rolls 11, 12, many stripe electrodes 14 are provided on a base body roll 13 on which at least the surface has electric insulating property, and also its electrode is covered with an insulating and protecting layer 15. an alternating electric field E is formed on the surface of the rolls 11, 12, a dielectric polarization 17 is generated in magnetic toner 5 by this electric field E, and as a result, the toner 5 is caught on the surface of the rolls 11, 12, and subsequently, contained in the inside housing 2b by adjacent scraping blades 18, 19. In this way, the leakage of the magnetic toner is prevented exactly without breaking a magnetic latent image. |
