Inkjet printer system with a pair of motor assemblies

1. An inkjet printer system comprising:

a media tray for storing stacked print media;

a media pick-up mechanism configured to pick respective sheets of print media from the media tray;

a pair of transport rollers configured to transport print media from the pick-up mechanism;

motor assemblies configured to drive the respective pick-up mechanism and transport rollers; and

a printhead configured to eject ink upon print media transported by the transport rollers, the printhead including:

a chassis assembly defining a plurality of spaced apart first groups of apertures and a channel;

an ink distribution unit defining a plurality of ink distribution passages and a plurality of spaced apart second groups of apertures wherein the apertures of each second group are in fluid communication with respective ink distribution passages, the ink distribution unit being received in the channel so that the first and second groups of apertures coincide: and

a plurality of printhead modules serially engaged along the chassis assembly and in fluid communication with respective first groups, the printhead modules being configured to eject ink provided from the ink distribution passages via said first and second groups.

2. An inkjet printer system as claimed in claim 1 , wherein the printhead is configured to eject ink at a predetermined time from the pick-up mechanism picking a sheet of print media.

3. An inkjet printer system as claimed in claim 1 , in which the printhead is configured to eject ink responsive to a media sensor detecting the presence of a sheet of print media.

4. An inkjet printer as claimed in claim 1 , wherein the chassis assembly includes:

a chassis defining the channel and two sets of notches located on either side of the channel; and

an elongate support plate received in the channel and defining a plurality of peripheral tabs located within respective notches.

5. An inkjet printer as claimed in claim 1 , wherein each printhead module includes a plurality of unit cells, each unit cell including:

a multi-layer substrate defining an ink inlet;

one or more side walls extending from the substrate around the ink inlet;

a nozzle plate supported by the side walls to define a chamber in fluid communication with the ink inlet, the nozzle plate defining an outlet through which ink in the chamber can be ejected; and

a looped and elongate heater element suspended within the chamber, and which can be heated so that bubbles are generated in ink within the chamber and ink is ejected from the outlet.

6. An inkjet printer as claimed in claim 5 , wherein the heater element is configured so that the bubbles merge to form a single elongate bubble extending transverse to the side walls.