Patent · US Expired

Removable developing units for a copying machine and display for indicating the useful life of the machine

US4974020A · kind A · utility

61Cited by
17References
48Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 22, 1987
Grant dateNov 27, 1990
Priority date
Expiry dateSep 22, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2221/1869
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An image-forming machine, such as an electrostatic copying machine, having a number of optional features. A display device is provided for displaying the number or type of toner cartridge loaded in the main body of a developing device. An image-forming condition adjusting device is provided for adjusting the image-forming conditions in response to a toner cartridge loaded in the main body. A life signal producing device is provided for signaling the end of the service life of the electrostatographic material. The life signal is produced in response to a cartridge replacement signal and a final cartridge signal. Alternatively, the life signal is produced in response to a final cartridge signal and either a signal indicating a predetermined number of rotations of the image-bearing member or a cartridge replacement signal, whichever is produced earlier. A toner removing blade is held at a non-operating position when a process unit is detached from the image-forming machine and positioned in a unit holding box. When a predetermined number of toner cartridges have been selectively loaded and detached into and from the developing device, loading of a new toner cartridge is prevented. Whe…

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