Optical ribbon edge sensor having means for adjusting the switch sensitivity to the selected ink color
US4767933A · kind A · utility
4Cited by
3References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 21, 1987 |
| Grant date | Aug 30, 1988 |
| Priority date | — |
| Expiry date | Jul 21, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J17/36
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
An adjustable optical ribbon edge sensor having a relatively short throat for ease of loading a towel ribbon in a high-speed line printer includes one or more pairs of photosensitive switches, coupled through a variable resistor, to a comparator facilitates accurate and repeated detection of the ribbon edge regardless of the color of the ribbon. By adjusting the variable resistor, the comparator is biased for the particular color ribbon in use.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.