Abstract: A fully automatic failure recovery method and system are described. The method and system achieve selected priming and flushing of one of plural capped printheads in response to an ink drop detector that indicates the need therefor. The priming duration and pressure are adjustable in accordance with the automatically determined extent of the failure of the selected printhead reliably to fire ink droplets. In its preferred embodiment, the system uses a plural cam and cam follower valve subsystem that has few moving parts the cams of which selectively are rotated via a one-way clutch with the ink-jet printer's paper feed drive motor to open a selected vacuum tube leading to an ink accumulator.

Abstract: In a shear mode type ink jet head, nozzle holes are disposed at substantially central portions of channels formed between barriers of piezoelectric material, and common ink reservoirs are provided at both ends of the channels. In one embodiment, two kinds of channels having different depths are formed in alternating succession on a board made of piezoelectric material. Channels of one depth are used as dummy channels and are kept empty, and channels of the other depth are filled with ink and the ink can be ejected from the channels through nozzle holes.

Abstract: A valve is disclosed for use in a maintenance station for an ink jet printer. The maintenance station has a carriage on which a cap that selectively seals the printhead nozzle is mounted. The carriage is movable in and relative to a fixed support member of the maintenance station. A flexible hose interconnects the cap with a pneumatic source for the removal of air and ink from the cap. The selective movement of the carriage towards and away from a wall of the support member pinches the flexible hose closed between them without requiring closely toleranced movement of the carriage.

Abstract: A drop on demand type ink jet printhead. The ink jet printhead includes a cover plate formed from an active material, a main body portion having an ink-carrying channel axially extending therein and a device for supplying a pressurized flow of ink to the ink-carrying channel. A rear side surface of the cover plate is mounted to a front side surface of the main body portion to block the ejection of pressurized ink therefrom. When an electric field is applied across the cover plate, the displacement of the cover plate caused thereby provides a path for the ejection of ink from the ink-carrying channel. Specifically, the cover plate includes an edge surface which extends from a front side surface thereof to the rear side surface such that, when the electric field is applied thereacross, an orifice defined by the edge surface and in communication with the ink-carrying channel is formed for the ejection of pressurized ink therefrom.

Abstract: A thermal transfer recording method involving providing a thermal transfer medium having a support and ink layer thereon, the binder being chosen so as to have a melt viscosity which falls within a range that is temperature dependent, contacting the thermal transfer medium with a recording medium, applying energy with a recording head to transfer an image to the recording medium, and moving, in a unit period of time, the thermal transfer material through a distance relative to the recording head that is smaller than the distance through which the recording medium moves in that time.

Abstract: Droplet ejectors having a plurality of droplet ejecting ports capable of ejecting ink droplets onto a recording medium and having a capping structure that alleviate debris contamination. The capping structure includes a plurality of openings, some of which allow ejected droplets to pass onto the recording medium. The capping structure is removably spaced above the remainder of the droplet ejector using spacers which mate with others openings in the capping structure.

Abstract: An ink jet printer head including a pair of body plates bonded together; a recess portion formed on at least one of the body plates, the recess portion having a plurality of pressure chambers and a plurality of orifices respectively communicating with the pressure chambers; a pressure generating section having a plurality of driving portions formed from a piezoelectric member, the driving portions having pressure applying surfaces respectively opposed to the pressure chambers; and a resin member molded with the pressure generating section inserted therein to form at least one of the body plates. Accordingly, even when the density of arrangement of the driving portions is increased, the resin member can be surely filled into each space between the adjacent driving portions, thus realizing high-density printing and improving the productivity of the ink jet printer head.

Abstract: A thermal ink-jet pen cartridge including an ink reservoir for maintaining ink under negative pressure. The ink reservoir is coupled to the printhead via a discharge port. To prevent air bubbles from entering the reservoir via the discharge port and printhead after ink is expelled via the thermal process, a check valve is placed in the fluid path between the ink reservoir and the printhead at the discharge port. The check valve is a mesh having a very small mesh opening sufficient to prevent air bubbles from passing through under normal pressures. The check valve also serves the function of a particulate filter to prevent contamination of the printhead by particles from the ink reservoir.

Abstract: An ink jet type recording head driving circuit comprises: a capacitor which is connected through a first switching transistor and a charging time constant adjusting resistor to a power source, and grounded through a second switching transistor and a discharging time constant adjusting resistor; and a current buffer through which the terminal voltage of the capacitor is applied to a pressure generating member scanning switch circuit. In the circuit, a first pulse for contracting a pressure generating member forming the recording head is applied to the first switching transistor, and a second pulse for expanding the pressure generating member is applied to the second switching transistor, so that the pressure generating member is contracted at a rate set by the capacitor and the charging time constant adjusting resistor, to supply ink into the pressure chamber of the recording head, and then it is expanded at a rate set by the capacitor and the discharging time constant adjusting resistor.

Abstract: A digital driver for an ink jet printhead and an associated method for selectively applying voltage to a piezoelectric sidewall actuator of the printhead. The digital driver includes positive, negative and neutral voltage sources, a first switching element having a first control input, a first voltage supply input connected to the positive voltage source and a first output, a second switching element having a second control input, a second voltage supply input connected to the negative voltage source and a second output, and a third switching element having a third control input, a third voltage supply input connected to the neutral voltage source and a third output. The first, second and third outputs are connected together to provide a common output for connection to the piezoelectric sidewall actuator.

Abstract: An ink jet recording head having a spacer including a pressure generating chamber, a reservoir, and an ink supply port connecting them, a nozzle plate, hermetically fixed on a first side of the spacer, for generating ink droplets when receiving an ink pressure from the pressure generating chamber, a vibrating plate, hermetically fixed on a second side of the spacer, for pressing the pressure generating chamber, and piezoelectric vibrators for pressing the vibrating plate, wherein the vibrating plate has thin portions each occupying a large area so that the compliance of a regional area closer to the nozzle openings is larger than a regional area closer to the ink supply port.

Abstract: In a print cartridge according to the preferred embodiment of the invention, a polymer tape having orifices formed therein and containing conductive traces has a substrate containing heater elements affixed to a back surface of the tape. Each of the heater elements in the substrate is located substantially behind each of the orifices. The edges of the nozzle member overlap the edges of the substrate, and the back surface of the tape is sealed with respect to an ink reservoir so that a seal substantially circumscribes the substrate. This allows ink to flow around the side edges of the substrate and into vaporization chambers associated with each orifice. The conductive traces on the tape are attached to electrodes along the shorter side edges of the substrate so as not to interfere with the edge-feed of ink along the longer edges of the substrate.

Abstract: A system for supplying liquid ink to a thermal ink-jet printing apparatus comprises a housing defining a single chamber having a ventilation port and an outlet port. A medium occupies at least a portion of the chamber, the medium being adapted to retain a quantity of liquid ink. A scavenger member is disposed across the outlet port, providing a capillary force greater than that of the medium.

Abstract: A droplet jet device for use in an ink jet printer. The device has a bottom ceramics plate into which parallel grooves for storing ink are cut. A covering plate is either fixedly or slidably mounted over the grooved side of the ceramic plate to enclose the grooves. The sidewalls of the grooves have electrodes mounted thereon. One end of each groove is connected to an opening serving as an ink jet and the other end is connected to a ink source. The ink jets may be smaller grooves connecting the grooves to a print face of the bottom ceramics plate or may be ends of smaller grooves in the cover plate, one of the smaller grooves in the cover plate partially overlapping a corresponding groove in the ceramics base plate. When a current is applied to selected electrodes, the associated walls are deformed by a piezoelectric effect to compress the groove and eject an ink droplet from the ink jet.

Abstract: The operation of U type drop-on-demand ink jet printheads are enhanced by selectively incorporating therein volume modifying tapers in the ink carrying channels, means for electrically isolating portions of the actuators thereof, and/or forming a variable layer of conductive material between the upper and lower sidewall portions therefore.

Abstract: An integrated multi-color drop-on-demand type ink jet printhead. The printhead includes a main body portion and a plurality of generally parallel, longitudinally extending ink-carrying channels arranged into at least two channel arrays. A manifold corresponding to each of the at least two channel arrays and in communication with each of the ink-carrying channels of the corresponding array is formed in the main body portion. Ink is supplied to each of the at least two channel arrays from a corresponding ink source, each of which is filled with a different color of ink.

Abstract: A jet print head (1) comprises a chamber (2) for current conductive ink (6) and an ink discharge port (3) to express ink onto the information carrier (4). The discharge port (3) has a group array of parallel rows of orifices (5) obtained in the form of flow-through openings communicating with the chamber (2) and represented by a multilaminate structure established on an underlay (8) and having layers forming electrodes (7) which are common for each row of orifices (5), and individual electrodes (10) for every orifice (5), produced as an integral whole together with the current conductive bar (12), and a magnetic layer (9) placed between them. The energy signal pulse sent to the electrodes (7,10) creates electro-dynamic force by virtue of which an ink drop is discharged from the given capillary tube to fall onto the information carrier (4).

Abstract: A head for a piezoelectric ink jet printer includes a plurality of ejector devices for ejecting ink droplets. Each ejector device has an ink channel body defining an ink channel. The head further includes a piezoelectric actuator secured to the ink channel for actuating the ejector devices. The actuator is made up of a plurality of piezoelectric ceramic layers, a plurality of internal positive electrode layers, and a plurality of internal negative electrode layers, which are laminated in such a manner that each piezoelectric ceramic layer is sandwitched between each internal positive electrode layer and each internal negative electrode layer. At least one of the internal positive electrode layers and the internal negative electrode layers are divided into a plurality of segments so as to be provided in association with respective ones of the plurality of ejector devices.

Abstract: An improved ink-jet printer of the so-called current flow type wherein a current is passed through a conductive ink contained between a pair of electrodes so as to cause the ink to become vaporized and cause trapped gasses or bubbles to expand suddenly, exerting a sufficient pressure upon the ink to force a droplet of ink from a nozzle is disclosed, wherein at least one projection of electrically insulating material is disposed between the pair of electrode for increasing the density of the current at a position directly below a nozzle. With the projection thus provided, only a limited portion of the conductive ink participates in the generation of heat, and boiling of the conductive ink takes place only at the position directly below the nozzle. Accordingly, droplets of conductive ink are produced with minimum power consumption and can be ejected in a uniform direction.

Abstract: In a droplet ejecting device capable of being driven at a low voltage and having a simple structure with low manufacturing costs, the droplet ejecting device has multiple ejectors each for changing a pressure of ink held in an ink passage by the use of a pressure generator so as to eject the ink held in the ink passage through an ejection port. The ejection ports comprise a slit disposed across the multiple ink passages and the slit is formed into a tapered cross section thereby eliminating a required process for manufacturing the same number of tapered ejection ports as that of ink passages in the prior art. Therefore, it is possible to reduce the number of manufacturing processes, manufacturing costs, and a driving voltage.