Patent ID: 9141035
Filing Date: 2015-09-22
Classification: G03G

Abstract:
1. A developing device comprising: a developing roller configured to include a magnet roller having numerous magnetic poles in a circumferential direction thereof and a roller-shaped developing sleeve sheathed on the magnet roller and to feed toner to a photosensitive drum; a regulating blade configured to extend in a rotation axis direction of the developing sleeve, disposed opposite to a circumferential surface of the developing sleeve, and configured to regulate a quantity of the toner present on the circumferential surface of the developing sleeve; and seal members disposed opposite to the circumferential surface of the developing sleeve without being in contact with both ends of the developing sleeve in the rotation axis direction, and configured to inhibit the toner on the circumferential surface from moving to the rotation axis direction ends by magnetic brushes formed between the ma net roller and the seal members, wherein an inner surface part of each seal member which is opposite to the circumferential surface of the developing sleeve has root parts which extend in the rotation axis direction of the developing sleeve and which have crest parts formed in a serrated shape when viewed from a side in the rotation axis direction, and the seal members are configured such that, of flanks constituting each of the crest parts when viewed from the side, the flank at a downstream side in a rotational direction of the circumferential surface of the developing sleeve is formed to be longer than the flank at an upstream side, and an angle formed between the flank at the downstream side and the circumferential surface of the developing sleeve becomes an acute angle.