Modular printhead assembly with reservoir mounted printhead modules

1. A modular printhead assembly for an inkjet printer, the modular printhead assembly comprising:

an elongate chassis defining a plurality of slots;

an elongate ink reservoir fast with the chassis; the ink reservoir defining a plurality of longitudinally extending ink channels for storing respective types of ink, a plurality of spaced apart sets of ink outlets with the ink outlets of each set being in fluid communication with respective ink channels, and a plurality of receiving formations located along the ink reservoir which can receive a plurality of printhead modules; and

the plurality of printhead modules which are configured to engage, in a releasable manner, with the elongate ink reservoir such that respective sets of ink outlets can supply print ink to respective printhead modules, each printhead module including a plurality of resilient fastening legs configured to be received within the receiving formations at particular locations during engagement so that access to the legs is thereafter enabled through the slots to facilitate disengagement of the printhead modules from the ink reservoir a body defining a plurality of ink chambers which can be placed in fluid communication with respective ink channels of the ink reservoir; a rib cage comprising a plurality of ribs and for mounting to the body, a gap being defined between each adjacent pair of ribs and a groove being defined transverse to the ribs; a film for covering the rib cage; and a printhead integrated circuit for mounting to the film in a location coincident with the groove such that, in use, ink passes from the ink chambers, along the gaps and into the groove before being fed to the printhead integrated circuit.

2. A modular printhead assembly as claimed in claim 1 , wherein the slots are arranged to form two parallel rows of spaced apart slots.

3. A modular printhead assembly as claimed in claim 1 , wherein the legs terminate in inwardly protruding feet to thereby enable snap fitting of the printhead modules to the ink reservoir.

4. A modular printhead assembly as claimed in claim 1 , wherein the ink reservoir includes an ink reservoir molding and a lid molding which can be secured to the ink reservoir molding.

5. A modular printhead assembly as claimed in claim 4 , wherein the lid molding has heat stakes for securing the ink reservoir to the chassis.

6. A modular printhead assembly as claimed in claim 1 , wherein the chassis includes an elongate metal plate in which the slots are defined, and a strengthening flange which extends along and from the plate.

7. A modular printhead assembly as claimed in claim 1 , wherein each printhead module comprises:

a body defining a plurality of ink chambers which can be placed in fluid communication with respective ink channels of the ink reservoir;

a rib cage comprising a plurality of ribs and for mounting to the body, a gap being defined between each adjacent pair of ribs and a groove being defined transverse to the ribs;

a film for covering the rib cage; and

a printhead integrated circuit for mounting to the film in a location coincident with the groove such that, in use, ink passes from the ink chambers, along the gaps and into the groove before being fed to the printhead integrated circuit.