US 12,246,534 B2
Liquid droplet ejecting device
Takaaki Yoshino, Nagoya (JP); Toru Kakiuchi, Chita (JP); and Taisuke Mizuno, Yokkaichi (JP)
Assigned to BROTHER KOGYO KABUSHIKI KAISHA, Nagoya (JP)
Filed by BROTHER KOGYO KABUSHIKI KAISHA, Nagoya (JP)
Filed on Mar. 13, 2023, as Appl. No. 18/182,455.
Claims priority of application No. 2023-009099 (JP), filed on Jan. 25, 2023.
Prior Publication US 2024/0246335 A1, Jul. 25, 2024
Int. Cl. B41J 2/045 (2006.01)
CPC B41J 2/04581 (2013.01) [B41J 2202/10 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A liquid droplet ejecting device comprising:
a channel member having a channel, the channel including a nozzle and a pressure chamber communicating with the nozzle; and
an actuator on the channel member and configured to apply a pressure to a liquid in the pressure chamber,
wherein a diameter of the nozzle and a natural frequency of the channel are parameters of the liquid droplet ejecting device to satisfy that:
(a) the actuator has a threshold drive frequency of 100 kHz or more;
(b) a droplet of the liquid has a volume of 1.8 pl or more; and
(c) the Ohnesorge number is 0.2 or more,
with the following formulas (1) (2), and (3) satisfied:

OG Complex Work Unit Math
wherein F is the threshold drive frequency (KHz), D is the diameter of the nozzle (μm), and Fr is the natural frequency (kHz),

OG Complex Work Unit Math
wherein V is the volume of a droplet (pl), D is the diameter of the nozzle (μm), and Fr is the natural frequency (kHz), and

OG Complex Work Unit Math
wherein Oh is the Ohnesorge number, μ is a viscosity of the liquid (mPa·s), ρ is a density of the liquid (g/m3), and σ is a surface tension of the liquid (mN/m).