Ink jet print head with capillary flow cleaning

摘要

The present invention resides in a self-cleaning printer with a print head having an orifice plate defining an ink jet orifice, a cleaning orifice and a drain orifice. The orifice plate further defines an outer surface between the orifices. A source of pressurized cleaning fluid is connected to the cleaning orifice and a fluid return is connected to the drain orifice for storing used cleaning fluid. A cleaning surface is disposed adjacent to and separate from the outer surface to define a capillary fluid flow path from the cleaning orifice across the ink jet orifice and to the drain orifice. During cleaning, the source of pressurized cleaning fluid discharges a flow of a cleaning fluid into the capillary fluid flow path and pressurized cleaning fluid from the capillary flow path passes through the drain orifice and into the fluid return.