The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 19, 2000
Filed:
Oct. 14, 1998
Mineyuki Sako, Toyokawa, JP;
Shinichi Yoshimoto, Aichi-Ken, JP;
Suguru Hamamichi, Toyokawa, JP;
Yukihiko Okuno, Toyokawa, JP;
Minolta Co., Ltd., Osaka, JP;
Abstract
The present invention is to provide a developing apparatus having a supply screw and a recovery screw both of which are arranged vertically to circulate developer, wherein a component in a normal direction of pressure generated by the recovery screw is made larger than that of pressure generated by the supply screw. Thereby, lowering and raising of developer is suppressed and occurrence of fog on the image and the smoke of toner are prevented. Alternatively, a radial member and a centrifugal member are applied to the supply screw and the recovery screw, respectively. Thereby, developer is prevented from moving between screws in the midst of the transportation. Still alternatively, a preliminary stirring portion is provided on extension of a stirring screw at upperstream side. The preliminary stirring portion has a cylindrical body with inlets and outlets. Both inside and outside of the cylindrical body, screws are provided and inclines of screw blades are reversed to each other. Thereby, it enables the developing apparatus to transport the developer which is sufficiently stirred and charged to a development zone without being accompanied by a large-scaled apparatus.