Liquid discharging head, head cartridge and liquid discharge apparatus
US5992984A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 1997 |
| Grant date | Nov 30, 1999 |
| Priority date | — |
| Expiry date | Jul 9, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2202/21
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
This invention provides, in a novel liquid discharge method utilizing a movable member, a configuration for detecting presence or absence of liquid in the liquid path or discharge state of the liquid. In an embodiment of this invention, the element substrate of the liquid discharge head is rendered electrically conductive and a partition wall for separating a liquid path for the liquid to be discharged and a liquid path for generating energy for liquid discharge upon heating is also rendered electrically conductive, and a detecting pulse is applied to the partition wall to detect the difference in potential or the variation in electrostatic capacitance between the element substrate and the partition wall, whereby the presence or absence of liquid in the small liquid path is detected. Also in another embodiment, the electrostatic capacitance between a fixed electrode provided in a fixed position of the liquid discharge head and a movable electrode provided on the movable member is detected, and the discharge state of the liquid is judged according to the function state of the movable member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.