Method and structure for controlling the energizing of an ink jet printhead in a value dispensing device such as a postage meter
US5815172A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 23, 1996 |
| Grant date | Sep 29, 1998 |
| Priority date | — |
| Expiry date | Aug 23, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/04591
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method for controlling energizing of an ink jet printhead includes the steps of generating encoder pulses to a motor to activate the motor to move the printhead at a desired speed over a recording medium; generating and sending fire pulses at a fire pulse frequency from an ASIC to an ink jet printhead driver chip to selectively energize ink jet printhead nozzles to eject drops of ink onto the recording medium based on a predetermine relationship between an expected encoder pulse frequency and the fire pulse frequency; compensating for variations in the speed of the ink jet printhead movement caused by variations in the encoder pulse frequency by using the ASIC for continuously comparing the encoder pulse frequency to the fire pulse frequency and for adjusting the fire pulse frequency based upon the variations to the encoder pulse frequency to maintain the predetermined relationship thereby synchronizing the ink jet printhead movement with the energizing of the printhead nozzles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.