Abstract: A printhead includes a liquid manifold. A filter is in fluid communication with the liquid manifold. A nozzle plate includes a length and an array of nozzles extending along the length of the nozzle plate. A liquid chamber is positioned between the nozzle plate and the filter. The liquid chamber is in fluid communication with the array of nozzles and the filter and includes a width that is substantially perpendicular to the length of the nozzle plate. The liquid chamber includes a structure that is spaced apart from the nozzle plate and spaced apart from the filter. The structure spans the width of the liquid chamber. A liquid source provides a liquid through the manifold, the filter, the liquid chamber under pressure sufficient to jet individual streams of the liquid from the array of nozzles.

Abstract: A printhead includes a liquid manifold. A filter is in fluid communication with the liquid manifold. A nozzle plate includes a length and an array of nozzles extending along the length of the nozzle plate. A liquid chamber is positioned between the nozzle plate and the filter. The liquid chamber is in fluid communication with the array of nozzles and the filter and includes a width that is substantially perpendicular to the length of the nozzle plate. The liquid chamber includes a structure that is spaced apart from the nozzle plate and in contact with the filter. The structure spans the width of the liquid chamber and includes a plurality of flow through channels. A liquid source provides a liquid through the manifold, the filter, the liquid chamber under pressure sufficient to jet individual streams of the liquid from the array of nozzles.

Abstract: The invention relates to continuous ink jet printing of an aqueous pigmented ink composition recycled from a main ink supply reservoir, employing a printer with a fluid delivery system capable of measuring the ink electrical resistivity, and providing needed quantities of either vehicle replenisher fluid or fresh ink to maintain the desired recycled ink concentration. The electrical resistivity of the pigmented ink can be modified advantageously for stable ink recycling by the addition of the organic amine salt of an acid, and the pH stability of the ink can be simultaneously improved by the additional inclusion of the neutral form of the organic amine in similar molar proportions to the amine salt. The pigmented ink jet ink compositions provide for particularly stable and invariant fluid properties during periods of extended printer operation and ink recirculation.

Abstract: A printhead includes a liquid manifold. A filter is in fluid communication with the liquid manifold. A nozzle plate includes a length and an array of nozzles extending along the length of the nozzle plate. A liquid chamber is positioned between the nozzle plate and the filter. The liquid chamber is in fluid communication with the array of nozzles and the filter and includes a width that is substantially perpendicular to the length of the nozzle plate. The liquid chamber includes a structure that is spaced apart from the nozzle plate and in contact with the filter. The structure spans the width of the liquid chamber and includes a plurality of flow through channels. A liquid source provides a liquid through the manifold, the filter, the liquid chamber under pressure sufficient to jet individual streams of the liquid from the array of nozzles.

Abstract: A printhead includes a liquid manifold. A filter is in fluid communication with the liquid manifold. A nozzle plate includes a length and an array of nozzles extending along the length of the nozzle plate. A liquid chamber is positioned between the nozzle plate and the filter. The liquid chamber is in fluid communication with the array of nozzles and the filter and includes a width that is substantially perpendicular to the length of the nozzle plate. The liquid chamber includes a structure that is spaced apart from the nozzle plate and spaced apart from the filter. The structure spans the width of the liquid chamber. A liquid source provides a liquid through the manifold, the filter, the liquid chamber under pressure sufficient to jet individual streams of the liquid from the array of nozzles.

Abstract: The invention relates to continuous ink jet printing of an aqueous pigmented ink composition recycled from a main ink supply reservoir, employing a printer with a fluid delivery system capable of measuring the ink electrical resistivity, and providing needed quantities of either vehicle replenisher fluid or fresh ink to maintain the desired recycled ink concentration. The electrical resistivity of the pigmented ink can be modified advantageously for stable ink recycling by the addition of the organic amine salt of an acid, and the pH stability of the ink can be simultaneously improved by the additional inclusion of the neutral form of the organic amine in similar molar proportions to the amine salt. The pigmented ink jet ink compositions provide for particularly stable and invariant fluid properties during periods of extended printer operation and ink recirculation.

Abstract: A sensor includes a first set of electrodes, a second set of electrodes, and at least one electrical circuit. The first set of electrodes is completely submergible in a fluid. The second set of electrodes is partially submergible in the fluid. The at least one electrical circuit is configured to measure resistance of the fluid between the first set of electrodes and configured to measure resistance of the fluid between the second set of electrodes.

Abstract: The present invention relates to ink output in ink jet printing systems. A refractometer is used to control the concentration of inks used in continuous ink jet printers. A concentration detector measures the total amount of light reflected from a surface. Changes in the ink cause a definite change in sensor output. As the refractive index is changed, shifting the critical angle for internal reflection, more or less light is reflected to the sensor. The index of refraction can be determined from the sensor once corrections are made to account for temperature dependencies of the sensor and light source and baseline measurement of reflected light amplitude. These dependencies are carried out in the refractometer.

Abstract: A system to recycle waste ink for reuse as replenishment fluid is for an inkjet print station that includes a printhead with a fluid inlet and a fluid outlet. The system uses an ink supply tank, an external ink supply tank with fresh ink and an ink supply valve to control ink flow from the external ink supply tank to the ink supply tank. The system includes a replenishment fluid supply valve for controlling flow between a replenishment fluid supply and the ink supply tank, a device for monitoring ink concentration in communication with ink, a waste tank and a waste reuse valve for controlling flow between the waste tank and ink supply tank. The system includes level sensors and one or more controllers to control any valves, sensors, and pumps associated with the system to optimize operation of the system.

Abstract: A system and method are provided for protecting the vacuum pump of an ink jet printer system from the harmful effects of condensation in the vacuum lines, and from the harmful effects of moisture and water in the vacuum lines. This is accomplished by suppressing the condensation and drying the vacuum line walls.

Abstract: An electronic printing system comprises a substrate supply for supplying a substrate along a paper path configured in an arc. The substrate is controllably transported through the electronic printing system past a plurality of printheads. The printheads are arranged above the paper path, in an arc configuration corresponding to the paper path configuration. As the substrate passes under each printhead, a printed image is generated on the substrate. A plurality of rollers are arranged to have at least one roller under the substrate at each location corresponding to a printhead location. Finally, a dryer is located after the last of the plurality of printheads for fixing the printed image to the substrate.

Abstract: A print engine module for use with a remote print head is an integral unit having removable drawers and permanently installed drawers, each drawer containing a component of an ink jet printer. The removable drawers contain a fluid system unit, a charge power unit, a power supply unit, and a card cage unit. Also within the print engine module are two fixed components that are in drawers permanently attached to the print engine module cabinet. The permanent units include power distribution unit and a computer unit.

Abstract: A fluid system is usable with a four inch print head of a continuous ink jet printer. The fluid system controls all critical ink jet functions. The fluid functions electronically feedback-controlled by the fluid system include pressure control at the print head. The fluid system also controls ink temperature during startup and ink concentration. Finally, the fluid system controls vacuum level.

Abstract: An improved construction for a continuous ink jet printing system of the kind having a chamber for receiving a plurality of ink cartridges, a plurality of ink supply sub-systems for delivering ink from the cartridges to respective print heads and a plurality of ink return sub-systems for returning ink from the print heads to respective cartridges. The cartridge chamber is constructed to be substantially air-tight and the ink cartridges have a vent opening to their interior. The chamber itself is coupled to a vacuum source and the cartridges in the chamber are maintained at the chamber pressure via their vent openings. The chamber evacuating source includes a source of compressed air and a venturi devcie coupled to the housing interior and the compressed air source. The compressed air source also can be coupled, via check valves structure, to provide drying air to the print heads.

Abstract: An ink cartridge constructed for insertion into a continuous ink jet printer, includes a reservoir for containing an ink supply, an outlet for coupling the ink reservoir to a printer supply line, cartridge venturi elements having (i) a restriction region, (ii) an expansion region and (iii) an inlet for detachable coupling to an ink bypass line of such printer. The cartridge also includes an ink return inlet couplable to an ink return line(s) of the printer and a path defining an ink induction passage that extends from the venturi restriction region to the ink return inlet. Structural features of printer apparatus, adapted to cooperate with such a cartridge, are also disclosed.

Abstract: A cleaning system for ink jet printing orifices includes cooperative elements which provide varying pressure differentials across the orifice plate that oscillate ink into and out of the orifices. In one embodiment the pressure differentials are implemented by varying the impedance to ink cross-flow through a print head cavity while pressurizing a region around the exterior of the orifices.

Abstract: An ink circulation system for continuous ink jet printers includes a replaceable ink cartridge, forming a supply/return reservoir, and cooperative positioning and interconnection structure of the printer apparatus. The cartridge includes valved ports that are adapted to cooperate with valved terminals of the printer conduits in a manner obviating ink spillage. The system provides cooperative positioning and engagement structures of the cartridge and printer, which simplify cartridge insertion and removal.

Abstract: A glass assembly for forming a wall or roof-light, comprises a planar array of sealed multiple glazing units which are secured to supporting members by mechanical fixings which pass through the outer glass sheets of the units outside the seals of the units. The outer glass sheets are sealed edge-to-edge.

Abstract: An ink supply system for supplying ink to the print head of an ink jet printer includes a pump arrangement having a pump outlet for supplying ink to the print head from a supply tank through a print head supply line. A closed container communicates with the pump outlet and the print head for holding a quantity of ink therein for providing a second flow of ink to the print head at a static pressure that increases linearly with time. A valve controllably actuated by a solenoid selectively directs a portion of the ink from the pump outlet to the closed container, gradually compressing the air therein as the container is filled. Ink is thereby supplied to the print head at a gradually increasing static pressure, facilitating initiation of production of jet drop streams by the print head.