Inkjet Nozzle Device With Static And Movable Nozzle Chamber Portions

Abstract

A nozzle device for an inkjet printer includes a support structure defining an ink inlet chamber connected to a source of ink; an elongate actuating arm cantilevered relative to the support structure; and a nozzle chamber structure defining a nozzle chamber for receiving ink from the ink inlet chamber, the nozzle chamber structure comprising a static portion extending from the support structure, and further comprising a movable wall portion mounted to the actuating arm between the ends of the elongate actuating arm. The elongate actuating arm terminates in a free end within the nozzle chamber, the free end adapted to move within the nozzle chamber to eject ink therefrom. The elongate actuating arm is positioned to divide the nozzle chamber from the ink inlet chamber.

1 . A nozzle device for an inkjet printer, the nozzle device comprising:
 a support structure defining an ink inlet chamber connected to a source of ink;   an elongate actuating arm cantilevered relative to the support structure; and   a nozzle chamber structure defining a nozzle chamber for receiving ink from the ink inlet chamber, the nozzle chamber structure comprising a static portion extending from the support structure, and further comprising a movable wall portion mounted to the actuating arm between the ends of the elongate actuating arm, wherein   the elongate actuating arm terminates in a free end within the nozzle chamber, the free end adapted to move within the nozzle chamber to eject ink therefrom, and   the elongate actuating arm is positioned to divide the nozzle chamber from the ink inlet chamber.   
   
   
       2 . A nozzle device as claimed in  claim 1 , wherein the actuating arm includes an active portion connected electrically to a current source, and which heats and expands upon activation of the current source, and a passive portion electrically isolated from the current source and mechanically coupled to the active portion via at least one separating element. 
   
   
       3 . A nozzle device as claimed in  claim 1 , further comprising a static formation extending from the support structure toward the actuating arm at a location proximal to the movable wall portion, the static formation impeding the escape of ink from within the nozzle chamber during actuation of the actuating arm with an ink meniscus formed between the static formation and the actuating arm. 
   
   
       4 . A nozzle device as claimed in  claim 3 , wherein the static formation defines a free end which is directed away from the nozzle chamber. 
   
   
       5 . A nozzle device as claimed in  claim 4 , wherein the support structure defines a well located in alignment with said free end for collecting any ink leakage from the nozzle chamber. 
   
   
       6 . A nozzle device as claimed in  claim 1 , wherein the free end of the actuating arm comprises a paddle substantially spanning the nozzle chamber. 
   
   
       7 . A nozzle device as claimed in  claim 1 , further comprising a movement sensor for facilitating determination of the degree or rate of pivotal movement of the actuating arm. 
   
   
       8 . A nozzle device as claimed in  claim 7 , wherein the movement sensor comprises a movable contact element extending from the active portion, and a fixed contact element extending from the support structure in a position so that the movable contact element contacts the fixed contact element upon activation of the current source. 
   
   
       9 . A nozzle device as claimed in  claim 8 , wherein the active portion is substantially U-shaped and the movable contact element is located proximal to the centre of the active portion. 
   
   
       10 . A nozzle device as claimed in  claim 9 , wherein free ends of the active portion define a pair of enlarged contacts.