Method and system for detecting nonfunctional elements in an ink jet printer
US6199969A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1998 |
| Grant date | Mar 13, 2001 |
| Priority date | — |
| Expiry date | Jul 31, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K2215/0085
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and system for detecting a nonfunctional element in an ink jet printhead is disclosed. The ink jet printer system includes: a switching power supply, coupled to the inkjet printhead, for supplying power to the printhead; an output capacitor, coupled to an output of the switching power supply, for storing a dc voltage therein; a bleed resistor, coupled in parallel to the output capacitor, for discharging current from the output capacitor; an output shifting circuit, coupled to the switching power supply, for shifting the dc voltage level across the output capacitor between a low state and a high state; and a sensor, coupled to the output of the switching power supply, for detecting when the switching power supply is switching, wherein an element of the printhead is tested by measuring a test current discharging from the output capacitor when the element is activated and comparing the measured test current with a reference current which discharges from the output capacitor through the bleed resistor. The method includes: supplying regulated power to the printhead; storing the regulated power in a capacitor so as to provide a dc voltage across the capacitor; shifting the dc v…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.