Patent · US Expired

Image forming apparatus

US4937622A · kind A · utility

25Cited by
1References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 22, 1988
Grant dateJun 26, 1990
Priority date
Expiry dateNov 22, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/70
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An image forming apparatus having a plurality of copy paper detector sensors in a delivery passage for copy paper. After a first copy paper detector sensor has been turned ON, if a copy paper detector sensor just downstream of the first copy paper detector sensor is not turned ON within a predetermined period of time, there are checked the ON/OFF status of the first copy paper detector sensor and copy paper detector sensors upstream thereof. If one or more of the copy paper detector sensors are ON, the length of the copy paper is compared with a distance between each of the last-mentioned copy paper detector sensors and a copy paper detector sensor just downstream thereof. Based on the comparison result, the position where the copy paper has jammed, is judged.

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