Abstract: According to one aspect of the invention, an ink droplet forming mechanism for use in an ink jet printer system includes an ink discharge nozzle for discharging a printing ink; at least two heating elements activatable individually to heat a printing ink at the nozzle to form an ink droplet; and a controller connected individually to each heating element for activating at least two heating elements so that should one heating element fail at least one other will heat a printing ink at said nozzle to form an ink droplet.

Abstract: A method an apparatus for maintaining a predetermined ejected ink drop volume in a continuous inkjet printer is provided. An ink parameter, for example, temperature, velocity, flow rate, viscosity, is monitored. A time period between activation control signals provided to an ink drop forming mechanism is varied in response to a change in the ink parameter. The apparatus includes an ink parameter monitoring device which provides an input signal to a controller. The controller varies the time period between activation control signals provided to the ink drop forming mechanism.

Abstract: A method and apparatus for printing an image is provided. The apparatus includes a droplet forming mechanism adapted to form a succession of droplets having a first volume travelling along a path and a droplet having at least one other volume travelling along the path. A droplet deflector system applies force to the droplets travelling along the path. The force is applied in a direction such that the droplets having the first volume separate from the droplet having the at least one other volume.

Abstract: A continuous stream ink jet printer including a printhead having at least one nozzle or continuously ejecting a stream of ink droplets. A heater disposed adjacent to the nozzle thermally deflects selected ink droplets by asymmetrically heating the ink droplets to effect a printing operation. A cooling unit cools the ink provided to the printhead nozzle to increase the deflection angle of the droplets.

Abstract: Imaging apparatus includes a printhead with one or more nozzles, wherein heaters are positioned proximate to the nozzles. Electrical activation of the heaters creates ink droplets having a plurality of volumes. The use of higher-energy pulses in the portion of the waveform of heater activation associated with the formation of small drops results in more constant relative drop velocities and consequently, improved image quality. The printing apparatus also contains a droplet deflector having a gas source positioned at an angle with respect to the stream of droplets thereby separating ink droplets having one of the plurality of volumes from ink droplets having another of the plurality of volumes. An ink guttering structure is provided for capturing one range of ink-drop volumes, while allowing another volume range to strike an image receiver.

Abstract: A liquid emission device includes a chamber having a nozzle orifice. Separately addressable dual electrodes are positioned on opposite sides of a central electrode. The three electrodes are aligned with the nozzle orifice. A rigid electrically insulating coupler connects the two addressable electrodes. To eject a drop, an electrostatic charge is applied to the addressable electrode nearest to the nozzle orifice, which pulls that electrode away from the orifice, drawing liquid into the expanding chamber. The other addressable electrode moves in conjunction, storing potential energy in the system. Subsequently the addressable electrode nearest to the nozzle is de-energized and the other addressable electrode is energized, causing the other electrode to be pulled toward the central electrode in conjunction with the release of the stored elastic potential energy. This action pressurizes the liquid in the chamber behind the nozzle orifice, causing a drop to be ejected from the nozzle orifice.

Abstract: A continuous stream ink jet printhead includes an ink droplet forming mechanism operable to selectively create a stream of ink droplets having a plurality of volumes and a droplet deflector having a gas source. The gas source is operable to interact with the stream of ink droplets thereby separating ink droplets having one of the plurality of volumes from ink droplets having another of the plurality of volumes. A sensor senses ambient pressure transients and is coupled to a controller which adjusts the gas flow, through a pressure compensation mechanism, to compensate for pressure transients.

Abstract: An apparatus for printing an image is provided. The apparatus includes a droplet forming mechanism operable in a first state to form droplets having a first volume travelling along a path and in a second state to form droplets having a plurality of other volumes travelling along the same path. A droplet deflector system applies force to the droplets travelling along the path. The force is applied in a direction such that the droplets having the first volume diverge from the path while the droplets having the plurality of other volumes remain travelling substantially along the path or diverge slightly and begin travelling along a gutter path.

Abstract: Apparatus for controlling ink in a continuous inkjet printer in which a continuous stream of ink is emitted from a nozzle bore, including a reservoir containing pressurized ink; a rigid nozzle element defining an ink staging chamber and defining a nozzle bore in communication with the ink staging chamber arranged so as to establish a continuous flow of ink in a ink stream; ink delivery structure intermediate the reservoir and the ink staging chamber for communicating ink between the reservoir and defining first and second spaced ink delivery channels; and heat responsive bimorph flexible elements disposed in the first and second spaced ink delivery channels to control the flow of ink to the nozzle and thereby change the direction of ink from the nozzle.

Abstract: An ink jet printer having an array of nozzles from which ink droplets of adjustable volume are emitted further includes a mechanism adapted to individually adjust the volume of the emitted ink droplets. The mechanism has a first state wherein the emitted droplets of selected nozzles are of a predetermined small volume and a second state wherein the emitted droplets of selected nozzles are of a predetermined large volume. A controller selectively switches the mechanism between its first and its second states such that ink droplets of the predetermined large volume are not simultaneously emitted from adjacent ones of the nozzles.

Abstract: Apparatus for controlling ink in a continuous inkjet printer in which a continuous stream of ink is emitted from a nozzle bore, including a reservoir containing pressurized ink; a rigid nozzle element defining an ink staging chamber and defining a nozzle bore in communication with the ink staging chamber arranged so as to establish a continuous flow of ink in a ink stream; ink delivery structure intermediate the reservoir and the ink staging chamber for communicating ink between the reservoir and defining first and second spaced ink delivery channels; and heat responsive bimorph flexible elements disposed in the first and second spaced ink delivery channels to control the flow of ink to the nozzle and thereby change the direction of ink from the nozzle.

Abstract: An inkjet printing apparatus is provided. The apparatus includes a source of ink and a printhead. The printhead includes an end nozzle and a second nozzle adjacent to the end nozzle. A portion of the printhead is shaped to balance forces acting on the ink ejected from the end nozzle.

Abstract: An apparatus for printing an image is provided. The apparatus includes an ink droplet forming mechanism operable to selectively create a stream of ink droplets having a plurality of volumes and a droplet deflector having a gas source. The gas source is positioned at an angle with respect to the stream of ink droplets and is operable to interact with the stream of ink droplets thereby separating ink droplets having one of the plurality of volumes from ink droplets having another of the plurality of volumes. The ink droplet producing mechanism has a nozzle and includes a heater positioned proximate to the nozzle. The heater may be selectively actuated at a plurality of frequencies to create the stream of ink droplets having the plurality of volumes. The heater may include an electrical resistance heating element. The gas source may be a positive pressure air source positioned substantially perpendicular to the stream of ink droplets.

Abstract: An apparatus for controlling errant ink drops in an inkjet printer having a plurality of nozzles for ejecting ink drops along a droplet trajectory and printing the ejected ink drops onto a receiver, including: at least one airflow channel arranged to provide a non-uniform airflow pattern located along a portion of the droplet trajectory, wherein the apparatus is in close proximity to the plurality of nozzles and prior to the receiver, such that the non-uniform airflow pattern provides compensation for errors in the printing of the ejected ink drops on the receiver and means for moving air in the airflow channel.

Abstract: An apparatus for printing an image is provided. In this apparatus, each nozzle is operable to selectively create a stream of ink droplets having a plurality of velocities. The apparatus also includes a droplet deflector having a gas source. The gas source is positioned at an angle with respect to the stream of ink droplets and is operable to interact with the stream of ink droplets thereby separating ink droplets into printing and non-printing paths.

Abstract: A continuous ink jet printhead and method are provided. The printhead includes an ink delivery channel. A plurality of nozzle bores are in fluid communication with the ink delivery channel. An individual obstruction is associated with each nozzle bore. Each individual obstruction is positioned in the ink delivery channel such that each obstruction creates a lateral flow pattern in ink continuously flowing through each of the plurality of nozzle bores as measured from a plane perpendicular to the plurality of nozzle bores.

Abstract: An apparatus for printing an image is provided. The apparatus includes a source of ink. A droplet forming mechanism is operable in a first state to form droplets from the source having a first volume traveling along a first desired path and in a second state to form droplets from the source having a second volume traveling along the first desired path. The droplet forming mechanism is positioned proximate the source. A first system selectively applies a first force to the source such that selected droplets formed from the source by the droplet forming mechanism travel along a second desired path. The first system is positioned proximate the source. A second system applies a second force to the droplets traveling along at least one of the first desired path and the second desired path. The second force is applied in a direction such that the droplets having the first volume diverge from the droplets having the second volume.

Abstract: An ink jet print head is formed of a silicon substrate that includes an integrated circuit formed therein for controlling operation of the print head. The silicon substrate has one or more ink channels formed therein along the longitudinal direction of the nozzle array. An insulating layer or layers overlie the silicon substrate and has a series or an array of nozzle openings or bores formed therein along the length of the substrate and each nozzle opening communicates with an ink channel. The area comprising the nozzle openings forms a generally planar surface to facilitate maintenance of the printhead. A heater element is associated with each nozzle opening or bore for asymmetrically heating ink as ink passes through the nozzle opening or bore.

Abstract: An ink jet printer includes a print head having a nozzle from which a stream of ink droplets is emitted. A mechanism is adapted to adjust a characteristic of the emitted ink droplets such that selected pairs of droplets emitted from the nozzle coalesce to form larger droplets while other ones of droplets emitted from the nozzle do not coalesce. A droplet deflector imposes a force on the droplets at an angle greater than zero with respect to the stream of ink droplets. The droplet deflector is adapted to interact with the stream of ink droplets to thereby separate non-coalesced ink droplets from coalesced ink droplets.

Abstract: Apparatus and process for controlling ink in a continuous ink jet printer in which a continuous stream of ink is emitted from a nozzle includes a droplet generator which causes the stream to break up into a plurality of droplets with an adjustable drop break off position having at least (1) a first drop break off position spaced from the nozzle and (2) a second drop break off position spaced from the first drop break off position. A stream deflector adjacent to the stream between the first drop break off position and the second drop break off position controls the direction of the stream between a print direction and a non-print direction. A charging apparatus is associated with the ink delivery channel to electrically charge the ink stream.