Printhead for modular printhead assembly
View Patent ↗A printhead module for a printhead assembly incorporating a number of modules spaced across a pagewidth in a drop on demand ink jet printer includes a first micro-molding and a second micro-molding separated by a mid-package film layer. The mid-package film layer has laser ablated holes and an adhesive layer on both faces providing adhesion between the first micro-molding, the mid-package film layer and the second micro-molding. The first and second micro-moldings are held in alignment by pins passing through corresponding apertures in the mid-package film layer. Ink inlets and an air inlet are provided in the underside of the second micro-molding. Ink and air passes from the second micro-molding, through the mid-package film layer to the first micro-molding. Air exits the first micro-molding to repel the print media from the printhead during printing. The ink passes from the first micro-molding into individual print chips mounted therein.
1. A printhead assembly incorporating at least one module comprising:
a first micro-molding locating a print chip having a plurality of ink jet nozzles, the first micro-molding having ink channels delivering ink to said print chip,
a second micro-molding having inlets through which ink is received from a source of ink, and
a mid-package film adhered between said first and second micro-moldings and having holes through which ink passes from the second micro-molding to the first micro-molding.
2. The printhead assembly of claim 1 wherein the mid-package film is made of an inert polymer.
3. The printhead assembly of claim 1 wherein the holes of the mid-package film are laser ablated.
4. The printhead assembly of claim 1 wherein the mid-package film has an adhesive layer on opposed faces thereof, providing adhesion between the first micro-molding, the mid-package film and the second micro-molding.
5. The printhead assembly of claim 1 wherein the first micro-molding has an alignment pin passing through an aperture in the mid-package film and received within a recess in the second micro-molding, the pin serving to align the first micro-molding, the mid-package film and the second micro-molding when they are bonded together.
6. The printhead assembly of claim 1 wherein the inlets of the second micro-molding are formed on an underside thereof.
7. The printhead assembly of claim 6 wherein six said inlets are provided for individual inks.
8. The printhead assembly of claim 6 wherein the second micro-molding also includes an air inlet.
9. The printhead assembly of claim 8 wherein the air inlet includes a slot extending across the second micro-molding.
10. The printhead assembly of claim 1 wherein the first micro-molding includes exit holes corresponding to inlets on a backing layer of the print chip.
11. The printhead assembly of claim 10 wherein the backing layer is made of silicon.
12. The printhead assembly of claim 1 further comprising an elastomeric pad on an edge of the second micro-molding.
13. The printhead assembly of claim 1 wherein the first and second micro-moldings are made of LCP.
14. The printhead assembly of claim 1 wherein a first surface of the first micro-molding has a series of alternating air inlets and outlets cooperative with a capping device to redirect a flow of air through the first micro-molding.
15. A printhead assembly incorporating a plurality of printheads as claimed in claim 1 , the printhead assembly including a channel along which the printheads are positioned.
16. The printhead assembly of claim 15 wherein the printhead modules have an elastomeric pad on an edge of their second micro-molding, the elastomeric pads bearing against an inner surface of the channel to positively locate the printhead modules within the channel.