Global Patent Index - EP 0375433 A3

EP 0375433 A3 19900912 - ACOUSTIC INK PRINTERS HAVING REDUCED FOCUSING SENSITIVITY

Title (en)

ACOUSTIC INK PRINTERS HAVING REDUCED FOCUSING SENSITIVITY

Publication

EP 0375433 A3 19900912 (EN)

Application

EP 89313455 A 19891221

Priority

US 28779188 A 19881221

Abstract (en)

[origin: EP0375433A2] To improve the tolerance of acoustic ink printers (21) to changes in their free ink surface (25) levels, provision is made for significantly reducing the effect of half wave resonances on the acoustic power density of the acoustic beam (30) or beams that are incident on the free ink surface (25) of such a printer (21), thereby reducing its focusing sensitivity. Some of the approaches that are taken to accomplish this rely upon acoustic losses to damp out the halfwave resonances and anti-resonances, while others employ multi-frequency rf voltage pulses for driving the droplet ejector (23) or ejectors so that the acoustic power perturbations caused by the half wave resonances and anti-resonances of the different frequencies tend to neutralize each other. Indeed, the use of an acoustically lossy ink (26) to dampen the half wave resonances and anti-resonances is compatible with selecting the frequency content of the acoustic radiation to neutralize them, so a combination of those two techniques can be employed, if desired, to carry out this ink printer (21).

IPC 1-7

B41J 2/015

IPC 8 full level

B41J 2/045 (2006.01); B41J 2/015 (2006.01); B41J 2/055 (2006.01); B41J 2/14 (2006.01)

CPC (source: EP)

B41J 2/14008 (2013.01); B41J 2002/14322 (2013.01)

Citation (search report)

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0375433 A2 19900627; EP 0375433 A3 19900912; EP 0375433 B1 19940706; DE 68916628 D1 19940811; DE 68916628 T2 19950112; JP H02219656 A 19900903; JP H0775890 B2 19950816

DOCDB simple family (application)

EP 89313455 A 19891221; DE 68916628 T 19891221; JP 32487389 A 19891214