Patent · US Expired

Electrophotographic developing unit

US6317576A · kind A · utility

6Cited by
8References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 21, 2000
Grant dateNov 13, 2001
Priority date
Expiry dateJan 21, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/09
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A magnetic member is arranged at a position on the downstream side with respect to the rotational direction of a developing sleeve, outside the developer conveyance path where the magnetism from the magnetic member has no influence on the magnetic field of the developing magnetic pole. When the magnetic member is arranged with its N pole facing the developing sleeve, the magnetic attractive force from the magnetic member weakens the developer's attraction to the peripheral surface of the developing sleeve. When the magnetic member is arranged with its S pole facing the developing sleeve, the developer being conveyed along the developer conveyance path is magnetized in such a direction as to repel the peripheral surface of the developing sleeve. In either case, the adhering state of the developer to the peripheral surface of the developing sleeve having passed through the developing position is unstable, so that the developer having adhered to the developing sleeve will easily drop off from the developing sleeve after passage of the developing position.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.