Apparatus for enhancing ink-flow reliability in a thermal-inkjet pen; method for priming and using such a pen
US5517217A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1992 |
| Grant date | May 14, 1996 |
| Priority date | — |
| Expiry date | Oct 30, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/16579
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Signals indicating ink-discharge presence control priming and preferably halt document creation pending ink resupply--or pending an operator command to go on without resupply. A detector senses ink discharge; circuits including a programmed microprocessor apply the detector signal to control, most typically, pen priming or repriming--and preferably related functions including suspension of printer operation. The detector preferably includes an optical source and detector along an optical path that intersects an ink-discharge path. With a pen that has multiple ink-discharge nozzles, preferably the apparatus distinguishes between ink discharge from the different nozzles (by correlation with nozzle-actuating pulses), and accordingly controls priming of each nozzle independently. Preferably this system is operated before starting to print a new sheet and upon newly installing a pen. In event of inadequate ink discharge, progressively more-energetic priming impulses (higher voltage or duration, or both) are directed to the pen, until adequate discharge results or no further energy increase is deemed suitable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.