Hewlett-packard Company

Ronald W Keil

Donald W Schulte

Robert W Shreeve

Michael D Dobbs

Mark S Barbour

Lucy E Burris

Joseph M Driear

Robert B Freund

A firing chamber configuration for the drop ejectors of inkjet printheads extends the life of the heat transducer by ensuring that bubble collapse (and attendant cavitation) occurs at a location well spaced from the heat transducer. The sidewalls of the firing chamber are shaped relative to the firing chamber entry in a manner such that a strong jet of inflow ink is provided for moving the collapsing vapor bubble from the center of the chamber and against a curved back wall of the firing chamber. In one preferred embodiment, the refill ink impinges on the back wall, divides, and is redirected away from the back wall toward pockets defined in chamber. The pockets are remote from the heat transducer. As a result, the refill ink urges the collapsing (bifurcated) bubble into the pockets where final collapse occurs away from the heat transducer.

Firing chamber geometry for inkjet printhead

A printhead apparatus and method has a plurality of ink drop generators coupled to a source of ink. Each ink drop generator includes an orifice with a corresponding ink firing chamber and a heating resistor, and a single ink feed channel coupling the firing chamber to the source of ink. The geometry of the ink drop generator relative to the heating resistor is selected to introduce an asymmetry to create a rotational component in the ink fluid velocity following a drop ejection. This swirl, in turn changes the location or intensity of the steam bubble, lessening the damage this collapse causes on the resistor, and thereby increasing the resistor life for the printhead. The asymmetry can be the shifting of a pinch point in the ink flow channel relative to the centerline of the channel, by offsetting of the ink flow channel, or by introducing the asymmetry by the relative location of the orifice or firing chamber relative to the firing resistor.

Asymmetric fluidic techniques for ink-jet printheads

Method and apparatus for creating an electrical connection between a tape-assisted bonding (TAB) segment having a plurality of conductive leads formed thereon and a printed circuit board also having a plurality of conductive leads formed thereon. A sheet of polymeric material having conductive elements mounted thereon so that each element protrudes from both sides of the sheet is disposed between a plurality of TAB segment leads and a corresponding plurality of generally opposing printed circuit board leads. A clamp secures the TAB segment to the printed circuit board thereby sandwiching the conductive elements between the TAB segment leads and the printed circuit board leads thus creating electrical connections between the opposing leads.

Method and apparatus for mounting an integrated circuit on a printed

A single spring presses a moving printhead against a pivotable platen while simultaneously engaging a sliding carrier upon two parallel cross slides. The printhead is mounted on an arm hinged to the carrier. The axis of the hinge is parallel to the line of motion of the carrier along the cross slides. The spring pushes the arm away from the carrier and produces a moment about the hinge which keeps the carrier engaged with the cross slides. The platen pivots to remain completely parallel to the surface of the printhead as the carrier moves along the cross slides.

Growing community of inventors

Carvallis, OR, United States of America

Ronald W Keil