Hewlett-packard Company

Other

John B Dunn

Lowell R McDaniel

Ralph L Stathem

Kevin D Almen

Peter R Stokes

David L Erickson

Wayne J Traina

Christopher P Murschel

Sandra J Smith

Bruce Cowger

Patrick W Shelley

Karen M Lewey

Douglas J Ullmer

Elwood H Barlow

Gregory P Merten

A disposable/refillable inkjet cartridge with bubble generator and an adhesively attached bubble generator vent cover. The cartridge is filed through a bubble generator opening in the cartridge bottom eliminating a separate filling orifice and easing the priming operation. The vent cover is adhesively attached making removal for refilling easier and avoiding suspected problems related to welding flash in welded vent covers. The bubble generator includes a tapered opening which receives a ball. The ball contacts ribs extending longitudinally along a tapered portion of the opening. The ribs are spaced over an arc of the opening. A bubble forms as needed between the ball and opening to maintain back pressure. The ribs and taper produce more consistent bubble pressures. A single piece of tape over the bubble generator and printhead nozzles avoids common causes for depriming.

Bottom fill inkjet cartridge through bubble generator

A firefighting training apparatus is provided for simulating the pumping of water through various long lengths of hose to train firefighters to deliver a proper amount of water through the fire hose. The apparatus includes a disk having one or more apertures therethrough. The one or more apertures permit the passage of water through the disk while providing resistance to the water to simulate the resistance encounted by water flowing through a long length of fire hose. The firefighting training apparatus is used by placing the disk within the flow of water through the fire hose. A firefighter can practice delivering a proper amount of water through a fire hose to a nozzle without the need of using a long length of fire hose.

Firefighting training method and apparatus

A flexible reservoir bladder is connected to the base of a pen body to define a reservoir volume that permits nearly all of the ink contained therein to be delivered from the pen by a print head. The back pressure developed within the reservoir volume is regulated by the resilient properties of the bladder and an orifice that permits controlled entry of air into the volume as the ink is depleted. The system is able to withstand severe environmental effects, such as a drop in ambient air pressure, while preventing pen leakage.

Ink delivery system for an ink-jet pen

A X-Y multiplex drive circuit and associated ink feed arrangement for an ink jet printhead wherein resistive heater elements, X-Y electrical interconnects thereto and closely adjacent ink feed ports are integrated on or within a given printhead substrate surface area with a maximum packing density and a minimum of fluidic crosstalk. Ink feed channels are formed within a printhead barrier layer which separates an ink jet orifice plate from an underlying printhead substrate, and state-of-the-art MOS planar processes and thin film deposition processes may be used for fabricating this drive circuit and its associated ink feed arrangement.

X-Y multiplex drive circuit and associated ink feed connection for

An improved ink storage system for ink cartridges which allows operation in a rapid and continuous manner while avoiding deprimes. A flexible, resilient ink bladder is provided which consists of an elongate reservoir that is closed at the bottom and open at the top with a tubular side wall therebetween. The bladder is supplied with ink, and a negative pressure is maintained therein. Due to the negative pressure, the side wall collapses inwardly upon ink delivery. To ensure that the wall collapses properly, the bladder is designed so the side wall thickness varies, with some portions of the wall being thinner than others. As a result, the thinner portions collapse inwardly toward the thicker portions during ink delivery. This prevents undesired increases in back-pressure within the bladder, thereby eliminating ink cartridge deprimes.

Collapsible storage bladder for ink cartridges

The firing resistor in a thermal ink jet pen is driven by two signals in sequence. The first signal is a warming signal, tailored to transfer a desired quantity of thermal energy to the ink in the firing nozzle. The second signal is a firing pulse tailored to vaporize ink adjacent the resistor and thereby eject a bubble of ink from the nozzle. The prewarming of the ink achieved by the warming pulse increases the volume of the vapor bubble produced by the firing pulse, thereby yielding a commensurately larger ink droplet. By varying the degree of prewarming, the droplets ejected by the firing pulse can be varied in volume, thereby effecting gray scale printing.

Method and apparatus for gray scale printing with a thermal ink jet pen

An ink cartridge system is provided which includes a reservoir maintained at a negative pressure in communication with a printing system. As the printing system is activated, ink is expelled from the cartridge which draws ink from the reservoir by capillary action. To prevent the reverse flow of air and ink into the reservoir, a control unit is provided. The control unit includes an ink conduit communicating with a standpipe. A medial section is provided between the ink conduit and standpipe. The medial section includes an opening adapted to receive a ball within the ink conduit. The ball is freely movable within the ink conduit, but is larger than the opening. As a result, the outward flow of ink from the reservoir is allowed, while the backflow of ink and air into the reservoir is prevented by movement of the ball into the opening of the medial section.

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Corvallis, OR, United States of America

John B Dunn