Recognition of ink expiry in an ink jet printing head
US5414452A · kind A · utility
100Cited by
5References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 27, 1993 |
| Grant date | May 9, 1995 |
| Priority date | — |
| Expiry date | May 27, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2002/17569
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
In ink jet printers in which the printing head (33) is connected to an ink reservoir (16), such as may be used in teleprinter or facsimile apparatuses, it is necessary to foresee the expiry of the ink in the reservoir in order to be able in due time to replace the printing head or the pertinent cartridge. A logic circuit (40) is used to count the number of drops gradually expelled, and, with any necessary correction, compares this number with the maximum number of drops equivalent to a known volume of ink contained on average in the reservoir. Expiry of the ink is indicated in in dependence on the result of the comparison.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.