International Business Machines Corporation

Lexmark International, Inc.

Her Majesty the Queen in Right of Canada, As Represented by the Minister

Graham Olive

Jerome Michael Eldridge

Francis C Lee

Gary Scott Keller

Peter Alfred Gruber

Kurt Edward Petersen

Arthur R Zingher

Alan Stirling Campbell

Ephraim Bemis Flint

Ronald Franklin Marks

George N Nelson

Joseph Guy Dionne

Robert C Durbeck

Royston Ernest Lake

Dean E Eastman

James O Moore

A thermal drop-on-demand ink jet print head in which conductor electrodes are formed on opposed surfaces of a print head substrate and extend to the edge of the substrate. An array of heater elements is formed on the edge of the substrate in electrical contact with the conductor electrodes. A nozzle plate is mounted with a nozzle aligned with each heater element, and a manifold is positioned to provide ink to the space between the nozzle plate and the edge of the substrate so that a drop of ink can be ejected from the nozzle each time the associated heater element is energized with a data pulse applied to a selected one of the conductor electrodes.

Thermal edge jet drop-on-demand ink jet print head

An array of resistive heater elements, each of which is connected in an electrical circuit between a common electrode and one of the control electrodes. Each of the resistive heater elements comprises a plurality of portions arranged so that a small elongated opening in provided at the middle of the heater element where no resistive material is present. Each of the resistive heater elements, when energized, has a bubble formed at each of the plurality of portions. All of the bubbles coalesce to form a single pillow-shaped bubble which causes a drop of ink to be ejected from the associated nozzle. During collapse of the bubble, the bubble collapses inwardly so that cavitational shock impacts the heater element at the opening and little or no damage to the resistive heater is produced.

Thermal drop-on-demand ink jet print head

A thermal drop-on-demand ink jet print head in which thermal cross-talk problems are eliminated by providing heat shield members in the space between each of the heater elements. The heat shield members comprise metal fingers attached to either the common heater electrode or one of the control electrodes. The heat shield members enhance flow of heat into the substrate to thereby minimize thermal cross-talk among adjacent channels.

A thermal drop-on-demand ink jet print head in which a heat delay means is provided covering a predetermined part of the resistive element. Upon connection of an electrical signal to energize the resistive element, nucleation occurs at an uncovered location on the resistive element and formation of the bubble proceeds in a direction toward the covered part of the resistive element to thereby utilize the inertial effect of the controlled bubble motion to eject a drop of ink in a more energy-efficient manner.

A thermal drop-on-demand ink jet print head in which an array of heating means is provided on one surface of a substrate member. A common electrode provides electrical contact to the heating means, and an array of data electrodes provides electrical contact to individual ones of the heating means. An array of feed through conductors is provided which pass through to the opposite surface of the substrate member to provide electrical contact between one of the data electrodes and one of an array of conductors leading to spaced solder pads on the opposite surface of the substrate member. A nozzle plate is mounted adjacent to the substrate member with a nozzle adjacent to each of the heating means so that, upon connection of an electrical signal to one of the solder pads, the corresponding heating means is energized and a drop of ink is ejected from the adjacent nozzle. Various embodiments are described in which multiplexing techniques are used to achieve a reduction in electrical connections and electronic drivers.

A method of joining a thermally conductive element to an electric circuit chip for cooling the chip includes initial steps of forming an oxide-free preform of a fusible metal alloy by extrusion of alloy between two mold blocks or plates. During the extrusion, the oxide coating is left behind so that the extruded alloy is essentially free of oxide. The extrusion takes place at a temperature elevated to approximately the liquidus temperature of the alloy. The preform, which may be in the form of a pill or section of thin foil, is placed between interfacing surfaces of the thermally conductive element and the chip, and is then extruded along the interfacing surfaces under pressure and elevated temperature to form a thermally conductive, oxide-free bonding layer of superior thermal conductivity.

Oxide-free extruded thermal joint

A system for cooling integrated circuit chips and particularly those involving very large scale integrated circuits; the system provides for closely associating the heat-sink or heat exchange element with the integrated circuit chip by having the heat-sink, in the form of a 'cooling chip', in intimate contact with the back surface of an integrated circuit chip (in a 'flip chip' configuration, the front, or circuit-implemented, surface, makes contact with a ceramic carrier or module); the cooling chip is provided with a plurality of spaced parallel grooves which extend along the one side or surface opposite the surface that is in bearing contact with the integrated circuit chip, whereby liquid coolant flows through the grooves so as to remove heat from the integrated circuit chip; further included in the system is a specially configured bellows for conducting the liquid coolant from a source to the heat-sink, and for removing the liquid coolant; a coolant distribution means, in the form of at least one glass plate or manifold, is provided with spaced passageways interconnecting the respective incoming and outgoing coolant flow paths of the bellows with the heat-sink.

Cooling system for VLSI circuit chips

A photoconductor-switched electroluminescent matrix panel for use in a laser-addressed tactical data display system in which photoconductor elements on the back of a screen are connected in series with electroluminescent display and feedback elements which form the front of the screen and an a-c power supply. The photoconductor has a high dark impedance so that in the initial OFF position insufficient a-c power passes through the electroluminescent elements to cause significant light emission. When the photoconductor is illuminated with a light pulse from a scanning laser beam, the impedance drops sharply so that substantially all of the a-c supply voltage is received by the electroluminescent element thereby causing the element to luminesce. The photoconductivity persists long enough for the electroluminescent emission to build up and sustain the low photoconductor impedance via optical feedback. This ON condition is maintained until the power to the device is interrupted for an erase period long enough for the photoconductivity to decay.

Growing community of inventors

San Jose, CA, United States of America

Graham Olive