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:
Aug. 05, 1997
Filed:
Sep. 18, 1995
Takatsugu Fujishiro, Tokyo, JP;
Minoru Suzuki, Yokohama, JP;
Hiroyuki Matsushiro, Yokohama, JP;
Noriyuki Kimura, Kawasaki, JP;
Katsuhiro Aoki, Yokohama, JP;
Chiyako Kobayashi, Tokyo, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A developing device capable of obviating the cohesion of toner and reducing the amount of dead toner is disclosed. The device has a developing unit accommodating a first and a second screw therein. The first and second screws extend from the toner hopper to the other longitudinal end of the developing unit in parallel to a developing roller and a supply roller. The first screw feeds toner from a toner hopper to a developing section. The second screw collects toner not contributed to development from the developing section and returns it to the first screw for recirculation. In this configuration, the collected toner and dead toner aggregating in the lower portion of the developing unit are forcibly moved to the developing section. The direction in which the screw portion of the second screw is inclined may be partly reversed to form a reverse transfer portion. Alternatively, a part of a casing adjoining the hopper may be implemented as a slant. The reverse transfer portion or the slant recirculates the toner more forcibly.