High flowrate filter for inkjet printhead
View Patent ↗A filter for an inkjet printer that has a chamber divided into an upstream section and a downstream section by a filter membrane. An inlet conduit establishes fluid communication between an ink supply and the upstream section. An outlet conduit establishes fluid communication between the downstream section and a printhead. During use at least part of the inlet conduit is elevated relative to the filter membrane. By elevating the inlet conduit relative to the filter membrane, it acts as a bubble trap to retain bubbles that would otherwise obstruct the filter. This allows the filter size to be reduced for a more compact overall design.
1. A filter for an inkjet printer, the filter comprising:
a chamber divided into an upstream section and a downstream section by a filter membrane, the chamber having a roof wall which during use, is an uppermost wall of the chamber;
an inlet conduit for establishing fluid communication between an ink supply and the upstream section, the inlet conduit incorporating a roof channel extending along the roof wall; and,
an outlet conduit for establishing fluid communication between the downstream section and a printhead; wherein during use,
the roof channel is elevated relative to the filter membrane and ink flows only downwards from the roof channel to the upstream section.
2. A filter according to claim 1 wherein the chamber has an internal height and width corresponding to the dimensions of the filter membrane and a thickness that is substantially less that height and width dimensions.
3. A filter according to claim 2 wherein the outlet conduit connects to the downstream section at its point with the lowest elevation during use.
4. A filter according to claim 3 wherein the filter membrane is rectangular and the inlet conduit connects to the upstream section at one corner and the outlet conduit connects to the diagonally opposed corner.
5. A filter according to claim 1 wherein the downstream section has a support formation for the filter membrane to bear against such that the filter membrane remains spaced from an opposing wall of the downstream section.
6. A filter according to claim 5 wherein the opposing wall is also a wall that partially defines the upstream section of a like chamber housing a like filter member, such that a number of filters are configured side-by-side.
7. A filter according to claim 1 wherein the filter is installed in a component of the inkjet printer that is intended to be periodically replaced.
8. A filter according to claim 1 wherein the filter is installed in a cartridge with a pagewidth printhead.
9. A filter according to claim 8 wherein the cartridge has a detachable ink coupling upstream of the filter for connection to an ink supply.