Fluid ejection device with printhead ink level sensor
US10155379B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 2014 |
| Grant date | Dec 18, 2018 |
| Priority date | — |
| Expiry date | Oct 29, 2034 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2202/18
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A fluid ejection device including a printhead die having a plurality of layers, including a single metal layer, and having an integrated ink level sensor. The ink level sensor includes an ink chamber above the metal layer, a metal plate of a sense capacitor disposed in the metal layer, and a clearing resistor circuit disposed in the metal layer including four clearing resistors arranged in a surround-4 configuration about the metal plate and electrically connected in parallel between a voltage potential and ground, wherein adjacent ends of at least two clearing resistors are not directly connected to one another so as to leave a gap between the adjacent ends in the metal layer. A metal lead in the metal layer extends through the gap to the metal plate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.