US 11,938,727 B2
Continuous fluid recirculation and recirculation on-demand prior to firing for thermal ejection of fluid having concentration of solids
Alexander Govyadinov, Corvallis, OR (US); Alex Trubnikov, Netanya (IL); and Ronald Albert Askeland, San Diego, CA (US)
Assigned to Hewlett-Packard Development Company, L.P., Spring, TX (US)
Appl. No. 17/795,039
Filed by Hewlett-Packard Development Company, L.P., Spring, TX (US)
PCT Filed Feb. 14, 2020, PCT No. PCT/US2020/018428
§ 371(c)(1), (2) Date Jul. 25, 2022,
PCT Pub. No. WO2021/162708, PCT Pub. Date Aug. 19, 2021.
Prior Publication US 2023/0054818 A1, Feb. 23, 2023
Int. Cl. B41J 2/14 (2006.01)
CPC B41J 2/14032 (2013.01) [B41J 2202/12 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method comprising:
continuously recirculating fluid through a thermal fluid-ejection printhead;
prior to firing a thermal resistor of the printhead to thermally eject a drop of the fluid through a nozzle of the printhead, recirculating the fluid on-demand through a chamber of the printhead between the nozzle and the thermal resistor; and
firing the thermal resistor to thermally eject the drop of the fluid through the nozzle,
wherein the fluid has a concentration of solids greater than 12% by volume.