DEVELOPING DEVICE WHICH PREVENTS IMAGE STAIN OWING TO DEFECTIVE EAR CUTTING

摘要

PURPOSE:To convey effectively and uniformly a developer and to prevent the defective ear cutting on a developing sleeve by making the width of the lower magnets among the magnets provided in several stages toward an image carrying body shorter than the width of the upper magnets. CONSTITUTION:Both ends in the transverse direction of the magnets have a larger magnetic field inclination and the developer sticks more thereto than to the other parts. A large amt. of the developer accumulates gradually on the rollers in the positions corresponding to both ends of the respective magnets and the sure ear cutting is not executed from a lower scooping roller 27 toward a developing sleeve 24 if all the magnets 35, 34, 28, 29, 31, 32 are made to the same width. The length in the transverse direction of the magnets is thereupon made shorter with the magnets existing in the position further from a photosensitive body 1 with respect to the magnets 35, 34 in the sleeve 24 and the magnets 28, 29 in an upper scooping roller 27. Then the developer is effectively and uniformly conveyed and the defective ear cutting on the developing sleeve is prevented.