Paper movement monitor
US4892426A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 30, 1988 |
| Grant date | Jan 9, 1990 |
| Priority date | — |
| Expiry date | Jun 30, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J15/06
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A monitor (18,26,28) monitors movement of paper (12) through a printer (16). The paper movement sensors (18,26) comprise one central wheel (70) or a pair of spaced edge wheels (158) each operating an individual photo-optic wheel (164,76). By counting pulses from the photo-optic wheels (76,164) monitor logic (28) determines conditions of jam, over-feeding and skew within the printer (16) both on an instantaneous and on a short term cumulative basis. The system self-calibrates through an initializing routine and later, continuously during operation. Paper movement sensors (18,26) are provided in dust-protected housings which can be chained together to provide monitoring facilities at many points.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.