Inkjet printhead assembly having printhead modules with nested ends
An inkjet printhead assembly includes an elongate support having a plurality of internal webs protruding from a base section to define a plurality of parallel ink supply channels; a shim mounted on the support and defining a plurality of rows of openings through which ink from respective supply channels is provided; and a plurality of elongate printhead modules mounted serially on the shim. Each module includes a carrier carrying a printhead. Each carrier defines a plurality of ink supply passages through which ink passes to the printhead from respective rows of the openings. Either end of each carrier defines complementary formations such that adjacent pairs of the carriers nest together. The plurality of internal webs protrude from the base section to define a semicircular recess in which the shim is received. The shim is received in the semicircular recess such that the each of the plurality of rows respectively align with one of the plurality of parallel ink channels.
1. An inkjet printhead assembly comprising:
an elongate support having a plurality of internal webs protruding from a base section to define a plurality of parallel ink supply channels;
a shim mounted on the support and defining a plurality of rows of openings through which ink from respective supply channels is provided; and
a plurality of elongate printhead modules mounted serially on the shim, each module including a carrier carrying a printhead, each carrier defining a plurality of ink supply passages through which ink passes to the printhead from respective rows of the openings, either end of each carrier defining complementary formations such that adjacent pairs of the carriers nest together, wherein
the plurality of internal webs protrude from the base section to define a semicircular recess in which the shim is received, and
the shim is received in the semicircular recess such that the each of the plurality of rows respectively align with one of the plurality of parallel ink channels.
2. An inkjet printhead assembly as claimed in claim 1 , wherein the complementary formations are stepped.
3. An inkjet printhead assembly as claimed in claim 1 , wherein the support is extruded and the inkjet printhead assembly further comprises a pair of molded endcaps mounted on either end of support.
4. An inkjet printhead assembly as claimed in claim 3 , wherein one of the endcaps defines a plurality of ink inlet tubes in fluid communication with respective ink supply channels.
5. An inkjet printhead assembly as claimed in claim 4 , wherein the other endcap defines a plurality of serpentine air grooves to equalize the air pressure in respective ink supply channels.
6. An inkjet printhead assembly as claimed in claim 1 , in which each module has a shield plate covering the printhead and defining slots in register with the printheads so that ink can be ejected through the slots.
7. An inkjet printhead assembly as claimed in claim 1 , wherein the support is shaped to provide a form-lock for retaining opposite edges of the shim as a snap fit.
8. An inkjet printhead assembly as claimed in claim 1 , wherein tape automated bond (TAB) film is wrapped around the support and carries signal and power connections to each printhead.
9. An inkjet printhead assembly as claimed in claim 1 , wherein the printheads are alternately disposed along the support to form a pair of parallel ranks of spaced apart printheads.
10. An inkjet printhead assembly as claimed in claim 9 , wherein the printheads in one rank overlap adjacent printheads in the other and rank along the support, thereby enabling continuous printing along the support.