Abstract: A dot-matrix printer is provided with different types of printheads which are interchangeably attachable to the printer carriage. The heads are provided with individual codes which are read by the printer control system and used to reconfigure its control function to suit the control requirements of the identified head. Such a system may include a microprocessor responsive to individual sets of instructions or programs providing new and different processing capabilities for printing control in response to the insertion of a new printhead.

Abstract: The connection and shielding system for modular RF circuits encases modular circuitboards (10) with five-sided enclosures (11). The sixth side of each enclosure is provided by the top ground plane of a base circuitboard (20) that supports and electrically interconnects the components of the modular circuitboards (10). Enclosures (11) are fixed to a grounded metal socket formed by fence strips (22) and metal inserts (23) which form upwardly open slots including yieldable longitudinal gaskets (50). Gaskets (50) yieldably grip the open end of enclosures (11) and seal them against escaping radiation. Further radiation shielding is provided about the base circuitboard (20) by the fact that the conductive signal traces provided in it are sandwiched between two continuous ground planes and run between plated-through vias joining the ground planes. The ends of each enclosure are provided with double wall baffles (17, 18) which provide airflow to the interior and RFI shielding through offset open apertures (13).

Abstract: The connection and shielding system for modular RF circuits encases modular circuitboards (10) within five-sided enclosures (11). The sixth side of each enclosure is provided by the top ground plane of a base circuitboard (20) that supports and electrically interconnects the components of the modular circuitboards (10). Enclosures (11) are fixed to a grounded metal socket formed by fence strips (22) and metal inserts (23) which form upwardly open slots including yieldable longitudinal gaskets (50). Gaskets (50) yieldably grip the open end of enclosures (11) and seal them against escaping radiation. Further radiation shielding is provided about the base circuitboard (20) by the fact that the conductive signal traces provided in it are sandwiched between two continuous ground planes and run between plated-through vias joining the ground planes. The ends of each enclosure are provided with double wall baffles (17, 18) which provide airflow to the interior and RFI shielding through offset open apertures (13).

Abstract: A new and improved thermal ink jet printhead and fabrication process therefor are described. In one embodiment of this invention, heater resistors are formed on one area of an insulating substrate and relative large area electrical contacts are formed on an adjacent area of the insulating substrate. A barrier layer is formed over the conductive trace pattern defining the heater resistors on the one area, and a small via in this layer provides an electrical path between the large area electrical contacts and the conductive trace pattern, and thus provides a current drive path for the heater resistors. The small via provides minimum exposure of the barrier sidewall area and area of the conductive trace pattern and thus improves device reliability and fabrication yields and also improves electrical contact to the printhead.

Abstract: Perceived quality of printing dot-on-dot graphics area fill using an ink-jet device is improved by printing swaths (30, 32, 34, 36, 38) of alternating colors, with each swath offset from the preceding swath by a predetermined amount. In this manner, banding (22, 22'), which is perceived with prior art printing methods, is substantially reduced.

Abstract: An ink composition for printing on plain paper and other media using a thermal ink-jet printer is provided. The ink composition comprises at least one member selected from the group consisting of ethylene glycol and diethylene glycol, present in an amount ranging from about 5 to 10 wt %; dye, ranging from about 1 to 4 wt %; and the balance water. A biocide ranging from about 0.01 to 0.3 wt % and/or a buffering agent ranging in concentration from about 0.05 to 0.5 wt % may also be included.The ink compositions of the invention permit printing on a large variety of plain papers, including bonds, photocopy paper and laser jet paper. These compositions are an improvement over other ink compositions and permit both high quality and letter quality printing to be achieved.

Abstract: We describe an integrated thermal ink jet printhead and manufacturing process therefor which includes the successive build-up of an orifice plate, a first barrier layer, heater resistors, a second barrier layer, and an ink reservoir-defining layer on top of a reusable or "dummy" substrate. Lead-in conductors are formed integral with the heater resistors by controlling the cross-sectional areas of these components, and openings (passageways) are formed between ink reservoirs and the orifice plate to provide for ink flow under control of the heater resistors. The dummy substrate is stripped away from the adjacent orifice plate, and the ink reservoir defining layer may be secured to an ink supply tank which supplies ink to the individual ink reservoirs. Thus, the orifice plate, heater resistors and ink flow paths of the printhead are self aligned, and the heater resistors are removed from direct cavitational forces from ink ejected from the orifice plate.

Abstract: A process for forming a dielectric patterned layer of any desired geometry on a selected substrate which includes vapor depositing selected reactants on said substrate only in areas thereon which are coextensive with the surface area of an adjacent metal electrode pattern.

Abstract: A rigid link is provided between a plot medium (14) and a position transducer (50) so that accurate plot medium advance measurement can be attained. The device (30) comprises a movable carriage (42) and an arm-like extension (38) that juts out from the carriage to the plot medium. A friction hold is made between the extension arm and the plot medium by applying a force to the extension arm normal to the plot medium by means of an electromagnet (33) which includes a coil (34), the extension arm serving as the armature. The electromagnet is located beneath the platen (12) which supports the medium on a base (32) which also supports the carriage.With the electromagnet activated, the extension arm is held against the plot medium. As the plot medium is advanced by a plot medium drive system (20), the extension arm and carriage are pulled along. Plot medium advance is stopped when the proper advance distance has been sensed by the position transducer.

Abstract: This invention is directed to an NPIN (or PNIP) diode structure and epitaxial process for fabricating same wherein the thickness and doping levels of the intermediate layers of the structure and such that these layers are substantially depleted of majority carriers and therefore enable the structure to be operated at zero volts DC bias. This structure may be utilized either as an efficient detector diode or a mixer diode substantially free of odd order harmonic mixing products, and both devices may be fabricated in a single molecular beam epitaxial process with the advantage of high control over epitaxial layer thickness and impurity concentration.

Abstract: A dye used in ink compositions for ink-jet printing comprises an aromatic dye molecule having attached to the backbone thereof from one to four polyhydroxyl-substituted groups having the formula selected from the group consisting of:(a) CH.sub.2 OH-(CHOH).sub.n CH.sub.2 O-, where n=2 to 10;(b) O.sub.n-1 C.sub.n H.sub.2n-1 -O-, where n=5 to 7; and(c) C.sub.6n H.sub.5n+1 O.sub.5n -O-, where n=1 to about 100. These dyes have improved water solubility and improved interaction with paper.

Abstract: A system for supplying ink to an ink jet pen wherein an off board ink supply is provided remote from the pen, and ink is fed from this supply to the pen by capillary action created during an ink jet printing operation. The pen includes a porous storage medium which is initially filled with ink at a slightly negative head. However, this negative head increases during ink depletion from the storage medium and provides the capillary forces necessary to pull ink into the storage medium from the off board ink supply. The driving energy for this action is provided by current drive to a thin film printhead of the pen, thus rendering the printhead multi-functional in purpose and simplifying the ink supply apparatus therefor. The use of an intermediate porous storage medium enables the ink supply system to accommodate large rates of changes in ink demand from the pen while still affording the user with a large ink capacity system in which disposable pens may be readily and easily replaced in a user-friendly operation.

Abstract: A plastic orifice plate for an ink jet printhead and manufacturing process therefor which includes electroforming a metal die having raised sections thereon of predefined center-to-center spacings, and using the die to punch out openings in a plastic substrate of a chosen thickness to form a plurality of closely spaced orifice openings in the substrate. The orifice plate can be of a chosen transparent material and secured to a printhead substrate where the dynamics of ink flow can be viewed through the orifice plate during printhead testing and evaluation.

Abstract: This specification describes a novel apparatus and method of manufacture wherein a corrugated fiberglass trough is sealed between matching end walls, consisting of stand and plug members which have sealing surfaces which match the contour of the fiberglass trough. In this manner, the bonding strength between the above members is maximized, the cost of manufacture is minimized, and assembly is made with ease.

Abstract: This application discloses a new and improved thermal ink jet printhead and method of manufacture wherein a tape automated bond (TAB) flexible circuit is sequentially thermosonically bonded in a one-by-one wire bonding process to aligned conductive traces on a thin film resistor substrate. These traces provide electrical current paths for a corresponding plurality of heater resistors on the substrate, and these resistors function to heat a corresponding plurality of ink reservoirs in a thermal ink jet printhead.

Abstract: In order to improve servo system stability and decrease settling times in rotary head positioners for high performance magnetic disc drives, a floating mass damper is mounted on the end of an accessing head arm structure of the positioner opposite to the end or ends carrying the magnetic head or heads. The damper includes a spring centered floating mass which rests on a viscous film, such as silicone oil, and the shear forces developed by motion of the floating mass across the film dissipates vibrational mode energy in the accessing head arm structure during both a fast seek operation followed by track following fine servo operation. Such energy dissipation thus reduces the settling time and amplitude of natural resonance of the head positioner.

Abstract: A multichamber ink jet pen has a printhead comprising a plurality of nozzle groups corresponding in number to the number of chambers. The nozzle groups are respectively in communication with the individual chambers for receiving ink. The multi-color ink jet pen is retrofittable in a single color printer to provide multicolor printing capability. The nozzles in the nozzle groups are formatted to correspond to the nozzle format in the printhead of the single color ink jet pen, including the same nozzle spacing, to take advantage of the single color printer control for that nozzle format. The nozzle groups each duplicate a different longitudinal segment of the single color nozzle column pattern.

Abstract: An aqueous-based ink composition for use in ink-jet printers in disclosed. The composition comprises (a) a vehicle of about 5 to 95% water and the balance at least one glycol ether, such as diethylene glycol; (b) a dye, such as Food Black 2, having at least one negatively charged functional group per molecule, present in an amount up to about 10% of the vehicle composition; and (c) a cationic compound selected from the group consisting of alkanol ammonium compounds and cationic amide compounds, present in an amount such that there is at least one molecule of cationic compound for at least one of the negatively charged functional groups on the dye, the pH of the ink composition being maintained in the acidic region below about 7.The ink composition of the invention evidences minimal crusting and reduced evaporation loss of water. The solubility of anionic dyes is increased in the acidic medium over that otherwise obtainable, due to the presence of the alkanol ammonium compound of amide.

Abstract: A process for manufacturing a thin film resistor substrate useful, for example, in fabricating an ink jet printhead, wherein discontinuous strips of conductive material are initially patterned on the surface of a resistive layer. These strips are formed using a first series of masking and etching steps of define an "X" dimension of a resistive heater element. Then, the conductive strips and resistive material therebetween are completely masked in preparation for a subsequent, second etching step used to remove the exposed portions of the resistive layer and thereby define a "Y" dimension of the resistive heater element. These steps leave smooth contours, good step coverage and high quality bevelled edges of the thus defined conductive and resistive layers. These layers are now ready for subsequent passivation layer, barrier layer and orifice plate deposition processes to complete a thin film printhead for use in an ink jet printer.

Abstract: Acoustic noises are suppressed in a large format drafting plotter (10) utilizing a paper drive motor (22) mechanically coupled to a paper drive shaft (20) by a geared timing belt (26) from the motor to a pulley (24) on the drive shaft by suitably modifying the pulley. The pulley is modified by enlarging the drive shaft hole (38) in the center thereof so as to provide slip-mounting of the pulley on the drive shaft. A winged clamp (30) is provided, mounted on the pulley, and having a central portion (34) having an opening (36) therethrough for engaging a portion of the drive shaft and a tightening screw (40) for securing the winged clamp to the drive shaft. The winged clamp also has two opposed extensions (42), which are each maintained between a pair of bosses (44) on the outside surface (24a) of the pulley, and isolated therefrom by a pair of isolator pads (32) comprising a compliant material.