Patent ID: 7484836
Filing Date: 2009-02-03
Classification: B41J

Abstract:
1. A drop ejection device, comprising: a group of orifices in a nozzle plate adapted to eject fluid drops, wherein the orifices in the group are arranged in a 2D array where at least some of the orifices are adjacent and have a same size and a maximum distance between each adjacent orifice in the group of orifices is less than any lateral dimension of each of the same sized orifices; a fluid conduit fluidly coupled to the group of orifices; an actuator capable of ejecting fluid in the fluid conduit through at least two of the orifices in the group; a controller coupled to the actuator; wherein the orifices and controller are configured such that the fluids ejected from the orifices merge into a fluid drop having a particular drop volume on the nozzle plate, and each orifice having a bubble pressure over 6 inch wg, the bubble pressure in each orifice being greater than a bubble pressure of a single nozzle ejecting the same drop volume; and a pressure regulator to apply a negative pressure to the fluid in the fluid conduit, the magnitude of the negative pressure being smaller than the bubble pressure in each orifice.