Ink jet print head
US4695852A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 23, 1986 |
| Grant date | Sep 22, 1987 |
| Priority date | — |
| Expiry date | Oct 23, 2006 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2002/14354
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A print element is actuated by a piezoelectric transducer controlled by a circuit which is capable of emitting a pulse in such a way that the reflection waves arising from expulsion pressure in the conduit for the ink are cancelled. The transducer is also connected to a circuit for detecting the pressure of the ink during the printing operation. A circuit for detecting the malfunctioning is capable of storing and signalling both the presence of bubbles in the conduit and the conduit empty condition. For bubbles, a flip-flop in the malfunction detecting circuit stores a signal indicating the presence of reflection phenomena when control circuit is operated for cancellation of the reflection waves. For the conduit empty condition it stores a signal indicative of the absence of reflection phenomena when the control circuit is operated in such a way that cancellation of the reflection waves does not occur.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.