Patent · US Expired

Image forming apparatus for detecting viscosity of a liquid type developer by utilizing a developer density detecting device

US6134394A · kind A · utility

21Cited by
6References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 15, 1999
Grant dateOct 17, 2000
Priority date
Expiry dateJul 15, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/105
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An image forming apparatus having an improved developer density detecting device for detecting density of a liquid type developer without using an optical sensor. Density of the liquid type developer is detected based upon viscosity of the liquid type developer, which is obtained by sensing pressures, for example, of the liquid type developer sent by a pump and flowing through a developer circulating pipe and applying pressure data obtained by sensing pressures to a predetermined formula. The viscosity can also be obtained by dropping a steel ball, or moving a steel ball, through the liquid type developer and measuring an induced current in a coil based on movement of the steel ball. The viscosity can also be obtained by measuring torque of a device rotating with the liquid type developer.

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