1
Jaime H Bohorquez, Charles E Schinner, John H Dion, Arthur R Hart, Niels J Nielsen: Protective capping apparatus for an ink-jet pen. Hewlett Packard Company, October 28, 1997: US05682186 (165 worldwide citation)

An ink pen is provided with a protective capping apparatus to protect against damage caused by the ingress of dirt and debris, the accumulation or solidification of ink, the discharge of static electricity or the like. The protective capping apparatus has a protective cap movable between an open pos ...


2
Niels J Nielsen: Ink jet printhead having a preloaded check valve. Hewlett Packard Company, William J Bethurum, June 30, 1987: US04677447 (119 worldwide citation)

A preloaded check valve disposed in a valve body between an ink reservoir and a printhead has a valve opening pressure or "cracking" pressure at least sufficient to overcome the hydrostatic pressure due to gravity of ink in the reservoir. This prevents depriming or leakage of ink at the orifices of ...


3
James E Pollacek, Niels J Nielsen: Regulator for ink-jet pens. Hewlett Packard Company, August 13, 1991: US05040002 (98 worldwide citation)

A regulator (20) for an ink-jet pen (24) that has a print head (30) for expelling ink from a fluid volume includes a seat (36) mounted to a pen body (26) and having a port (42) formed through it. A valve element (38) is mounted adjacent to the seat for movement relative to the port (42). Magnetic at ...


4
Kenneth E Trueba, William R Knight, Niels J Nielsen: Hydraulically tuned channel architecture. Hewlett Packard Company, William J Bethurum, November 21, 1989: US04882595 (91 worldwide citation)

The use of lumped resistive elements (28) in an ink feed channel (10) between an ink-propelling element, such as a resistor, (12) and an ink supply plenum (14) provides a means of achieving resistive decoupling and meniscus resonance control with a minimum of deleterious side effects and design comp ...


5
Bruce Cowger, Niels J Nielsen, John H Dion: Thermal ink jet pen having a feedtube with improved sizing and operational with a minimum of depriming. Hewlett Packard Company, June 5, 1990: US04931811 (80 worldwide citation)

An ink jet pen having a main ink reservoir therein connected to a thin film printhead by way of a large diameter standpipe, wherein the diameter of an air accumulating section of the standpipe is sufficiently large to enable ink to pass through the standpipe despite the presence of air in the air ac ...


6
Eldurkar V Bhaskar, Marzio Leban, Ulrich E Hess, Niels J Nielsen, Kenneth E Trueba, Ellen Tappon, Duane A Fasen: Thermal inkjet printer printhead with offset heater resistors. Hewlett Packard Company, Raymond A Jenski, June 3, 1997: US05635968 (75 worldwide citation)

A printhead includes a substrate with an ink feed aperture extending from a first surface to a second surface and a plurality of heater resistors disposed on it. Primitive groupings of the resistors are coupled to associated group power sources. An ink barrier layer is deposited on the substrate to ...


7
Scott W Hock, David A Johnson, Niels J Nielsen: Determining the operating energy of a thermal ink jet printhead using an onboard thermal sense resistor. Hewlett Packard Company, Dennis G Stenstrom, May 23, 1995: US05418558 (40 worldwide citation)

A method for operating a thermal ink jet printer including a printhead having ink firing heater resistors responsive to pulses provided to the printhead. A sequence of pulse bursts of respective increasing or decreasing pulse energies that span a predetermined pulse energy range is applied to the pr ...


8
Frank L Cloutier, Robert N Low, Paul H McClelland, Niels J Nielsen: Ink jet orifice plate having integral separators. Hewlett Packard Co, William H MacAllister, July 9, 1985: US04528577 (37 worldwide citation)

An orifice plate is provided of an electroformed material which incorporates an integral ink distribution manifold and integral hydraulic separators between orifices. The general approach to the method of making the orifice plate is to first construct a two-part mandrel made up of a "hard" mandrel w ...


9
Dana Seccombe, Niels J Nielsen, May Fong Ho, King Wah W Yeung, Lawrence A Hand: Ink-cooled thermal ink jet printhead. Hewlett Packard Company, Edward Maker II, Ron Griffin, October 17, 1995: US05459498 (34 worldwide citation)

An ink-cooled thermal ink jet printhead has an efficient heat exchanger located on the back side of the printhead that eliminates the need for heat sinks. All ink flowing to the firing chamber goes through the heat exchanger. The geometry of the heat exchanger is chosen so that almost all the residu ...


10
Dana Seccombe, Niels J Nielsen, May Fong Ho, King Wah Walter Yeung, Lawrence A Hand: Ink-cooled thermal ink jet printhead. Hewlett Packard Company, Roland Griffin, Edward Maker II, August 12, 1997: US05657061 (16 worldwide citation)

An ink-cooled thermal ink jet printhead has an efficient heat exchanger located on the back side of the printhead that eliminates the need for heat sinks. All ink flowing to the firing chamber goes through the heat exchanger. The geometry of the heat exchanger is chosen so that almost all the residu ...