Ink mixing system

A method of operating an ink jet printer comprising:

• providing an ink system comprising:
• a fluid tank comprising:
• a generally conically shaped side wall, the side wall sloping inwardly from a top portion to a bottom portion;
• and
• a bottom surface disposed adjacent the bottom portion of the side wall;
• and
• a first fluid conduit disposed in the fluid tank and comprising an opening adjacent and above the bottom surface of the fluid tank;
• and
• a second fluid conduit disposed in the fluid tank and comprising an opening at a location above the opening of the first fluid conduit;
• providing an ink source comprising a volume of ink;
• providing an solvent source comprising a volume of solvent;
• transferring substantially the entire volume of ink to the fluid tank through a supply line;
• and
• transferring a portion of the volume of solvent through the ink supply line to flush the supply line;
• further comprising performing a mixing process comprising:
• conveying the ink composition into the second fluid conduit and out of the first fluid conduit into the fluid tank for a first period of time, wherein the first period of time is at least 30 s;
• and
• reversing the flow of the ink composition to convey the ink composition into the first fluid conduit and out of second fluid conduit into the fluid tank for a second period of time, wherein the second period of time is at least 1 min, thereby mixing the ink composition.

An ink system of an ink jet printer comprising:

• a fluid tank comprising:
• a generally conically shaped side wall, the side wall sloping inwardly from a top portion to a bottom portion;
• and
• a bottom surface disposed adjacent the bottom portion of the side wall;
• a first fluid conduit disposed in the fluid tank and comprising an opening adjacent to and above the bottom surface of the fluid tank;
• a second fluid conduit disposed in the fluid tank and comprising an opening at a location above the opening of the first fluid conduit;
• a pump in fluid communication with the first fluid conduit and the second fluid conduit;
• an ink supply line in fluid communication with the pump;
• a print head in fluid communication with the ink supply line;
• a valve controlling the flow of fluid from the ink supply line to a nozzle in the print head, wherein the valve is a media separated valve;
• a return line in fluid communication between the print head and the fluid tank;
• and
• a filter module in fluid communication with the pump, wherein the filter module comprises:
• a housing;
• a filter media disposed in the housing;
• a fluid inlet disposed in the housing;
• and
• a fluid outlet disposed in a bottom portion of the housing, wherein the housing includes a generally conically shaped portion adjacent the fluid outlet.