Apparatus for driving a printhead and method of driving the printhead
US6398331B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 2000 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | Feb 4, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/04596
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
An apparatus for driving a printhead has a timer, a power supply, and a controller. The power supply applies a drive voltage to the printhead to eject ink drops from the printhead. The timer counts an elapsed time during which the printhead does not eject ink drops. The controller performs an ejection test where the drive voltage drives the printhead a plurality of times to eject a plurality of ink drops. The controller drives the power supply to increase the drive voltage in accordance with a length of the elapsed time. The ejection test is performed at a predetermined length of the elapsed time, the drive voltage and the predetermined length of the elapsed time are selected in accordance with a decrease in an ejection speed of the ink drops. The controller controls the drive voltage such that the surface of meniscus of ink in the orifice is subjected to fine vibration before the ink drop is ejected. The surface of the meniscus is subjected to fine vibration prior to either a printing operation or an ejection test. When the ejection test is performed, the controller determines the drive voltage by adding a first correction voltage to a drive voltage required for a printing operati…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.