Nozzle Device With Expansive Chamber-Defining Layer

Abstract

A nozzle device for an inkjet printhead includes a substrate assembly defining an ink supply; a chamber-defining layer defining a nozzle chamber in fluid communication with a nozzle opening and the ink supply; and an actuating arm coupled to the substrate assembly and terminating in a paddle separating the ink supply and nozzle chamber, the arm including a thermal bend portion proximal to the substrate assembly and configured to bend during actuation so that the paddle moves and causes ink within the nozzle chamber to be ejected out through the nozzle opening. A portion of the chamber-defining layer is supported by the thermal bend portion and the substrate assembly.

1 . A nozzle device for an inkjet printhead, the nozzle device comprising:
 a substrate assembly defining an ink supply;   a chamber-defining layer defining a nozzle chamber in fluid communication with a nozzle opening and the ink supply; and   an actuating arm coupled to the substrate assembly and terminating in a paddle separating the ink supply and nozzle chamber, the arm including a thermal bend portion proximal to the substrate assembly and configured to bend during actuation so that the paddle moves and causes ink within the nozzle chamber to be ejected out through the nozzle opening, wherein   a portion of the chamber-defining layer is supported by the thermal bend portion and the substrate assembly.   
     
     
         2 . A nozzle device as claimed in  claim 1 , wherein the actuating arm further includes a bridge between the paddle and the thermal bend portion, the bridge supporting another portion of the chamber-defining layer. 
     
     
         3 . A nozzle device as claimed in  claim 2 , wherein at least some of the thermal bend portion is exposed between said portions of the chamber-defining layer. 
     
     
         4 . A nozzle device as claimed in  claim 1 , wherein an active portion of the thermal bend portion is connected electrically to a current source within the substrate assembly. 
     
     
         5 . A nozzle device as claimed in  claim 4 , wherein the electrical connection is made to end terminals of the actuating arm, and the current source is configured to apply pulsed excitation drive voltage to said terminals. 
     
     
         6 . A nozzle device as claimed in  claim 4 , wherein a passive portion of the thermal bend portion is mechanically coupled to but electrically isolated from the active portion by posts with no current-induced heating occurring within the passive portion, the active portion being located between the passive portion and the substrate assembly.