Image forming apparatus including a paper feeding device having improved paper jam detection capability
US5485247A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1993 |
| Grant date | Jan 16, 1996 |
| Priority date | — |
| Expiry date | Aug 13, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/00548
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A paper feeding device is capable of judging that a paper jam occurs on the basis of output from a first paper detecting switch and a second paper detecting switch. These paper detecting switches are respectively provided ahead of and behind a registration roller which feeds paper sheets to an image forming section. If the first paper detecting switch is turned on when a predetermined time has elapsed since the registration roller started to feed a paper sheet to the image forming section, it is judged that a duplicate paper feeding state has occurred where a plurality of paper sheets are simultaneously fed. If the second paper detecting switch is turned off in the case where it is judged that a duplicate paper feeding state has occurred, it is judged that a paper jam has not occurred. The registration roller is stopped so it will later be ready to feed the subsequent paper sheet. Even when the paper sheets are simultaneously fed in a duplicate paper feeding state, it is not judged that a paper jam occurs as long as the paper sheets are fed one at a time to the image forming section. However, if both the first and second paper detecting switches remain on after the predetermined ti…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.