Abstract: An ink-jet printing system having a pressurized ink reservoir. Ink at elevated pressure is supplied to a back pressure regulator which reduces the pressure down for use by conventional ink-jet printhead. The ink reservoir can be either stationary and off-axis or movable and onboard with the printhead.

Abstract: Apparatus and method for refilling print cartridges for computer controlled printers. The apparatus creates a closed system that is isolated from ambient pressure. The apparatus utilizes both a vacuum in the ink reservoir in the print cartridge and vertical displacement of the refill reservoir with respect to the reservoir in the print cartridge to draw refill ink into the print cartridge to an operating level and to an operating pressure of less than ambient pressure. Within this closed system the apparatus dislodges the closure on the print cartridge and reseats a replacement closure during refilling.

Abstract: A thermal ink jet pen including a main ink storage compartment wherein a block of foam is completely sealed off from the surrounding ambient. The pen further includes an ink delivery section which is fluidically coupled at one end to the ink storage compartment and has a thin film printhead mounted on an outer surface thereof. The above main ink storage compartment includes a pair of flexible major side walls which begin to collapse as ink and air are drawn out of the pen during an ink jet printing operation. As this happens, and the collapsible side walls are forced into the opposite surfaces of the compressed foam block, and the inherent spring force of the foam block produces an equal and opposite force in equilibrium with these side walls within the ink storage compartment. This equilibrium condition operates to stabilize the negative backpressure within the ink storage compartment at a relatively constant value and prevents the pen from drooling ink.

Abstract: An electrostatic discharge structure protection structure formed on an interconnect circuit (20) that includes elongated interconnect lines (13) and interconnect contact pads (17) formed on a dielectric substrate (11) wherein portions of the interconnect circuit are subject to physical contact by a person. The electrostatic discharge protection structure includes an interconnected conductive grounding metallization ground pattern that includes a ground ring pattern (19) adjacent selected edges of the perimeter of the substrate and conductive metallization traces (29) adjacent selected edges of openings in the substrate. The electrostatic discharge protection structure further includes spark gaps (23a, 23b) formed between the interconnect pads and the conductive grounding pattern, and grounding pads (25') exposed by openings in the substrate.

Abstract: A conical vent (14) for a cartridge (10) is located on an inner surface (20) of the cartridge. The conical vent includes a conical-shaped member (26) having a base (28) and an apex (30). An opening (32) extends through the center of the conical-shaped member (26) to provide an air passage for a cartridge (10). The opening (32) is adapted to create a capillary force on a small amount of liquid (59) that might enter the opening to prevent any remaining liquid from leaking through the opening. The vent also includes a groove or capillary trap (34) that encircles the base of the conical-shaped member. Also, a pair of upright walls (36) and (38) surround the conical-shaped member and cooperate with the capillary trap to divert liquid to the base of the conical-shaped member and away from its apex.