Abstract: A liquid circulation device includes a supply unit that forms a flow path supplying a liquid from a reservoir unit; a collection unit that forms a flow path collecting the liquid to the reservoir unit; and N number of the connection units provided respectively corresponding to N number of ejection units ejecting the liquid forming a flow path connecting the supply unit and the collection unit via the ejection units, wherein with regard to each of N number of the connection units, a connection order of the connection units with respect to the supply unit, which is counted from upstream in a flow direction of the liquid in the supply unit coincides with a connection order of the connection units with respect to the collection unit, which is counted from upstream in the flow direction of the liquid in the collection unit.

Abstract: An ink system of an ink jet printer includes a fluid tank. The fluid tank includes a generally conically shaped side wall, the side wall sloping inwardly from a top portion to a bottom portion. A bottom surface is disposed adjacent the bottom portion of the side wall. A first fluid conduit is disposed in the fluid tank and includes an opening adjacent to and above the bottom surface of the fluid tank. A second fluid conduit is disposed in the fluid tank and includes an opening at a location above the opening of the first fluid conduit. A pump is in fluid communication with the first fluid conduit and the second fluid conduit. An ink supply line is in fluid communication with the pump. A print head is in fluid communication with the ink supply line.

Abstract: A liquid replenishment system for a printing apparatus that includes a dispensing nozzle and a supply reservoir is improved by a replenishment system having a volume control network responsive to a signal representative of the volume of liquid within the reservoir for generating a volume control signal. The volume control signal is applied to a pump operable to inject replenishment liquid from a replenishment source into the reservoir. The replenishment liquid is injected at a pressure at least substantially equal to the pressure in the reservoir and at a flow rate selectable in accordance with the volume control signal such that the volume of liquid in the reservoir is maintained at a predetermined reference level. A temperature control network for adjusting the temperature of the replenishment liquid to a temperature that lies within a predetermined range of the temperature of the liquid in the reservoir may also be provided.

Abstract: Method and Apparatus for Reducing Ink Foaming in a Continuous Inkjet Printer The invention provides a method of and apparatus for reducing foam formation in the returned ink in a continuous inkjet printer. The returned ink is subjected to deceleration and is reduced in pressure, preferably by being directed into a sub-chamber which reverses the direction of flow and provides an elevated edge over which the ink overflows. The de-aeration facility is preferably incorporated in an ink service module.

Abstract: A determiner determines whether a total ink amount in an ink circulation passage calculated by an ink amount calculator is less than an ink circulation necessary amount being an amount necessary for circulation of ink in the ink circulation passage, when a liquid level detector detects that a liquid level of the ink in an ink tank is lower than a liquid level corresponding to an ink circulation standard amount being a standard for ink circulation. A controller performs ink supply amount control to supply the ink from an ink bottle to the ink tank in such an amount that the total ink amount is kept below the ink circulation standard amount, when the determiner determines that the total ink amount is less than the ink circulation necessary amount.

Abstract: A method and apparatus for re-circulating a carrier in a printer is disclosed. The re-circulating system comprises a controller, a print head, a variable speed fan coupled to an air passageway and a condenser. The controller determines a liquid amount of carrier to be place on a page during a print operation. The controller adjusts the variable speed fan dependent on the amount of liquid carrier determined to be placed onto the page.

Abstract: A printing device includes a solution tank, a nozzle unit including a distribution path and a plurality of nozzles connected with the distribution path the nozzle unit being connected with the solution tank through a first pipe; a gas supply connected with the nozzle unit through a second pipe; and a discharge unit connected with the nozzle unit through a third pipe, wherein the distribution path includes first portions and second portions that respectively have different widths.

Abstract: An ink supply device for an inkjet recording apparatus including a back pressure tank 21, a distribution tank 12, a plurality of ink opening/closing electromagnetic valves 13, and a plurality of recording heads 14, in which the distribution tank 12 is connected to the back pressure tank 21 via an ink supply path 24, the plurality of ink opening/closing electromagnetic valves 13 is directly attached to the distribution tank 12 while being connected to the plurality of recording heads 14 via a distribution supply pipe 15 and the distribution tank 12 contains a humidification heater 71 for humidifying ink and a temperature sensor 72.

Abstract: An ink-jet recording head includes a recording head and pressure damper assembly module including a recording head part at a lower position having nozzle holes on an under surface and an ink passage communicating with the nozzle holes, and a pressure damper part higher than the recording head part having an ink containing chamber inside. The ink-jet recording head further includes first flexible tube supplying ink in the ink containing chamber to the ink passage and connecting an ink discharge part communicating with the ink containing chamber and an ink supply part at one end side in the recording head part communicating with one end of the ink passage; and a second flexible tube connected with another end side in the recording head part and communicating with another end of the ink passage. At least the inside of the first flexible tube is filled with the ink.

Abstract: The disclosed print head has a two-chamber main reservoir that decouples wasted ink and purge volume in print heads. The two-chamber structure of the print head allows for varying flow of ink through the print head's internal manifolds without varying the wasted ink out of the jet stack. The main reservoir of the print head includes a recirculation chamber and an incoming ink chamber. A vacuum is applied to a vent in the recirculation chamber and a pressure can also be applied to a vent in the incoming ink chamber to cause bubbles in the jet stack to move into the recirculation chamber and be removed through the recirculation chamber vent.

Abstract: A fluid ejection assembly includes a fluid slot, a recirculation channel, and a drop ejection element within the recirculation channel. A pump element is configured to pump fluid to and from the fluid slot through the recirculation channel. A first addressable drive circuit associated with the drop ejection element and a second addressable drive circuit associated with the pump element are capable of driving the drop ejection element and the pump dement simultaneously.

Abstract: An inkjet printer includes: an ink container having an outlet port and a return port; a printhead having a first ink port and a second ink port; a first ink line interconnecting the outlet port and the first ink port; a second ink line interconnecting the return port and the second ink port; a bypass line interconnecting the first and second ink lines; a valve system for controlling fluid flow through the first ink line and the bypass line; and a controller for controlling the valve system. During printing, the controller is configured to open the first ink line and the bypass line.

Abstract: An image forming apparatus includes an ink jet head, having a pressure chamber, a flow path and a nozzle, which ejects ink in the pressure chamber through the nozzle, a first tank connected to the flow path, a supply unit which supplies ink in the first tank to the pressure chamber through the flow path, a second tank connected to the flow path, a discharge unit which moves ink in the pressure chamber to the second tank through the flow path, and a control section which activates the supply unit and the discharge unit so that ink in the pressure chamber is discharged to the second tank by the discharge unit, ink in the first tank is charged to the pressure chamber by the supply unit and the liquid surface of ink supplied to the pressure chamber is projected from the nozzle.

Abstract: A liquid circulation device includes a supply unit that forms a flow path supplying a liquid from a reservoir unit; a collection unit that forms a flow path collecting the liquid to the reservoir unit; and N number of the connection units provided respectively corresponding to N number of ejection units ejecting the liquid forming a flow path connecting the supply unit and the collection unit via the ejection units, wherein with regard to each of N number of the connection units, a connection order of the connection units with respect to the supply unit, which is counted from upstream in a flow direction of the liquid in the supply unit coincides with a connection order of the connection units with respect to the collection unit, which is counted from upstream in the flow direction of the liquid in the collection unit.

Abstract: A liquid circulation unit adapted to be provided in a liquid circulation apparatus to circulate a liquid, including, a first liquid storage unit to store the liquid, a sensor to detect a fluid level of the liquid stored in the first liquid storage unit, a liquid sending pump to send the liquid to an outside from the first liquid storage unit based on a detection result of the sensor, a pipe arrangement for deaeration to remove a dissolved gas in the liquid sent from the liquid sending pump, a filter to remove an impurity in the liquid sent from the liquid sending pump, a diaphragm valve which opens when the liquid is sent to the outside from the first liquid storage unit, and a cock valve which opens when the liquid is sent to the first liquid storage unit from the outside, wherein the liquid circulation unit is adapted to be provided so as to be detachable to or from the liquid circulation apparatus.

Abstract: A fluid distribution system for a printhead. The system having a first fluid container a fluid connector for connection to a fluid input of the printhead; and a second fluid container connected between the first container and the connector for delivering fluid from the first container to the connector, wherein the second container is located relative to the first container and the connector so that a fluid pressure difference between fluid contained within the second container and fluid at the connector is independent of the amount of fluid contained within the first container.

Abstract: An object of the invention is to prevent, both bubbles and particles from being generated, when circulating ink in an inkjet head. The object can be achieved by an ink circulation apparatus, including: an ink tank that accumulates radical polymerization-type UV-curing ink so as to be in contact with gas including at least oxygen; an inkjet head; oxygen removing means that removes oxygen from the radical polymerization-type UV-curing ink; and control means that changes a mode between a first mode of removing oxygen from the radical polymerization-type UV-curing ink by the oxygen removing means and a second mode of not removing oxygen from the radical polymerization-type UV-curing ink and changes a mode from the first mode to the second mode before electric power of the apparatus is cut off.

Abstract: An ink circulation apparatus, including: an ink tank that accumulates radical polymerization-type UV-curing ink; a supplying flow path that communicates with the ink tank and a supply port of an inkjet head; a supply pump that supplies the ink accumulated in the ink tank to the inkjet head; oxygen removing unit that removes oxygen from the ink to be supplied to the inkjet head; a discharging flow path that communicates with a discharge port of the inkjet head and the ink tank; a collecting pump that collects the ink to be discharged from the discharge port in the ink tank; and oxygen supplying unit that supplies oxygen to the ink to be collected in the ink tank.

Abstract: The disclosed print head has a two-chamber main reservoir that decouples wasted ink and purge volume in print heads. The two-chamber structure of the print head allows for varying flow of ink through the print head's internal manifolds without varying the wasted ink out of the jet stack. The main reservoir of the print head includes a recirculation chamber and an incoming ink chamber. A vacuum is applied to a vent in the recirculation chamber and a pressure can also be applied to a vent in the incoming ink chamber to cause bubbles in the jet stack to move into the recirculation chamber and be removed through the recirculation chamber vent.

Abstract: In order to perform recording head maintenance by discharge and reflux of ink with higher pressures without creating instability of the meniscus in the nozzle surface, this image forming device may be provided with a recording head having multiple nozzles, a first reservoir unit and a second reservoir unit which store the ink supplied to the recording head, a supply unit which is opened and closed by a solenoid valve and connects the recording head and the first reservoir unit, a pump which supplies the ink in the second reservoir unit to the first reservoir unit, a recovery passage which is opened and closed by solenoid valves and connects the recording head and the second reservoir unit, and a control unit which controls operation of the solenoid valves and the pump.

Abstract: When filling a printing head with ink, ink in a sub-tank is circulated through a forward path port, a forward path, the printing head, a return path, a return path port, and the sub-tank by pumping ink from the forward path port side to the printing head side by a circulation pump in a state where a plurality of nozzles is sealed by bringing a contact member of a capping device into contact with a nozzle formation surface. Thereafter, sealing of the plurality of nozzles by the capping device is released while pressurizing the sub-tank by a pressure adjusting device.

Abstract: A printing apparatus includes an ink storage unit; a print head unit which has an ink reception port, an ink discharging device, and an ink exhaust port; an ink return path which is connected to the ink exhaust port and which returns ink exhausted from the ink exhaust port to the ink storage unit; and a cooling device which is arranged in the ink return path and which cools ink which passes through the ink return path.

Abstract: A printing device is equipped with a head, a first reservoir unit, a second reservoir unit, a first flow path connected to the head and the first reservoir unit, a second flow path connected to the first flow path and the second reservoir unit, a third flow path connected to the second reservoir unit and the second flow path, a first pressure supply unit provided on the second flow path, a second pressure supply unit, and a control unit for stirring the sedimentary ink by returning the sedimentary ink inside the second reservoir unit to the first reservoir unit using the second pressure supply unit after moving the sedimentary ink inside the first reservoir unit to the second reservoir unit using the first pressure supply unit.

Abstract: An inkjet printer includes: an inkjet printhead; an ink delivery system configured for supplying ink to the printhead at a negative hydrostatic pressure; and an air chamber in fluid communication with the ink delivery system. The air chamber has an air-permeable wall which is impervious to the ink. The air chamber provides dampening of pressure fluctuations in the ink delivery system and, further, is self-recovering from ingress of ink into the air chamber.

Abstract: An ink supply system for ink jet printers includes a recirculation tank coupled to a recirculation pump configured to provide a substantially pulseless flow of ink. A heating assembly having an ink conduit formed into a spiral in thermal contact with at least one heating element receives ink from the pump and outlets to a sensor assembly with temperature and pressure sensors that measure ink parameters both as the ink enters a printhead and is returned from the printhead. The returned ink is then ported to a recirculation tank from which the pump draws the recirculating ink. An air pump is coupled to the recirculation tank in order to maintain a substantial vacuum within the tank.

Abstract: An ink jet head is provided which includes: nozzles forming a predetermined array; liquid chambers respectively provided for the nozzles; pressure generation elements respectively provided for the liquid chambers which respectively discharge liquid in the liquid chambers; individual supply flow paths which respectively supply the liquid to the liquid chambers; a common supply flow path that is connected to each individual supply flow path and supplies the liquid into each individual supply flow path; and a liquid supply unit that circulates the liquid of the common supply flow path so as to make the liquid flow in one direction in the common supply flow path. The common supply flow path has a shape in which a cross-sectional area is increased and decreased at a predetermined interval. Each individual supply flow path is provided at a position where the cross-sectional area of the common supply flow path is increased.

Abstract: An image forming apparatus includes a recording head, a head tank, a main tank, a liquid feed device, and a controller. When the main tank is in an ink end state, the controller causes the feed device to feed the liquid in reverse from the head tank to the main tank. When air is unlikely to be mixed with the liquid or the liquid is unlikely to be bubbled in the head tank before installation of a new main tank, the controller causes the feed device to feed the liquid from the main tank to the head tank with an air release unit opened after the installation. When air is likely to be mixed with the liquid or the liquid is likely to be bubbled in the head tank before the installation, the controller causes the feed device to feed the liquid with the release unit closed after the installation.

Abstract: A fluid applicator mounting device includes a main body to removeably receive a fluid applicator module. The main body includes a common fluid channel having a main input port, a main output port, a supplemental input port to provide fluid to the fluid applicator module, and a supplemental output port to output fluid from the fluid applicator module. The fluid applicator mounting device also includes an input fm member disposed inside the common fluid channel and arranged proximate to the supplemental input port to guide fluid to the fluid applicator module. The fluid applicator mounting device also includes an output fin member disposed inside the common fluid channel and arranged proximate to the supplemental output port to guide fluid from the fluid applicator module away from the supplemental output port.

Abstract: An inkjet printhead adapter, including a chassis operative to accommodate one or more printheads and include one or more ink recycling valves and one or more ink supply valves communicating with an ink reservoir via an ink feeding tube and with one or more printhead accommodated in the adapter and wherein the ink supply valve is operative to direct a flow of ink from the feeding tube to one or more of the printhead and the ink recycling valve.

Abstract: The present invention provides a system and a method for recycling an inkjet-printing material. The recycling method comprises the following steps: utilizing a wiper configured to withdraw the inkjet-printing material dispensed by the nozzles, and collecting the inkjet-printing material by means of a recycling tank; mixing a fresh inkjet-printing material with the inkjet-printing material collected by the recycling tank, so as to form a reuse inkjet-printing material; and providing the reuse inkjet-printing material to the nozzles. The present invention can greatly save the inkjet-printing material.

Abstract: The invention describes a continuous inkjet printer having an ink distribution block and an ink module containing ink and filters which can be connected to the distribution block with a substantially horizontal linear sliding action. Spigots forming part of the connection are preferably provided with upward facing fluid transfer ports.

Abstract: A printing system includes an inkjet cartridge, an ink reservoir, and a reversible pump. A method and system of operating the printing system are providing in which first fluid line couples the ink reservoir and an input port of the inkjet cartridge. A second fluid line couples the reversible pump and an output port of the inkjet cartridge. The reversible pump is operated in a first direction to supply ink from the ink reservoir to the ink jet cartridge via the first fluid line. The reversible pump is a second direction to supply ink from the ink reservoir to the inkjet cartridge via the second fluid line. The reversible pump is operated in the first direction and the second direction repeatedly and sequentially for a predetermined duration.

Abstract: An ink delivery system includes a first tank including a fill sensor; a second tank including a fill sensor; a pump configured to pump ink from the first tank to the second tank; a third tank including a fill sensor; a print head in fluid communication with the second tank and the third tank. In an embodiment, the third tank is in fluid communication with the first tank and may be configured to provide a closed loop system, the second tank is in fluid communication with the third tank, and a pressure differential across the print head causes ink to flow through the print head. For some embodiments, pumps may be provided to control pressure differentials and print heads may print at one or more angles.

Abstract: A fluid distribution system for a printhead, the system having a fluid container fluidically interconnected with the printhead via a closed fluid flow loop, a gas vent on the closed loop and a multi-path valve on the closed loop for selectively allowing venting of gas in the closed loop via the gas vent.

Abstract: An inkjet printer (100) has an ink tank (113), an ink head (110), an ink supply tube (112) configured to supply ink from the ink tank (113) to the ink head (110), an ink return tube (115) one end of which is connected to an upstream side portion of the ink supply tube (112) and the other end of which is connected to a downstream side portion of the ink supply tube (112), and a pump (116) configured to circulate the ink in the ink supply tube (112) and the ink return tube (115).

Abstract: An ink droplet generation module for a print head assembly for a continuous ink jet printer, the printer having an ink supply system, a control system and a power supply system. The ink droplet generation module includes a supporting plate, an ink droplet generator, a charge electrode assembly, deflector plates, a phase measurement assembly, and a gutter tube, all attached to the supporting plate.

Abstract: A liquid storage unit for collecting a liquid supplied to an ejecting head is provided. The liquid is supplied to a plurality of ejecting heads via a pressure regulating valve, and the liquid is suctioned from the plurality of ejecting heads by a circulation pump, and then is discharged to the liquid storage unit. In this way, since the liquid is suctioned from each of the ejecting heads, the passage resistance is decreased, so that the ink can be appropriately circulated. In addition, since the ejecting head is supplied with the liquid at an appropriate pressure from the liquid storage unit via the pressure adjusting valve, the liquid can be appropriately ejected.

Abstract: A method of printing including providing an ink delivery system including a print head in fluid communication between a first tank and a second tank; and providing a pressure differential across the print head to cause ink to flow from the print head. With embodiments of the method, ink can be controllably dispensed from the print head at substantially the same velocity irrespective of the orientation of the print head with respect to the direction of the force of gravity.

Abstract: An ink circulation apparatus, including: an ink tank that accumulates radical polymerization-type UV-curing ink; a supplying flow path that communicates with the ink tank and a supply port of an inkjet head; a supply pump that supplies the ink accumulated in the ink tank to the inkjet head; oxygen removing unit that removes oxygen from the ink to be supplied to the inkjet head; a discharging flow path that communicates with a discharge port of the inkjet head and the ink tank; a collecting pump that collects the ink to be discharged from the discharge port in the ink tank; and oxygen supplying unit that supplies oxygen to the ink to be collected in the ink tank.

Abstract: A liquid ejection device includes a head section, a first liquid reservoir section, a supply passage, a second liquid reservoir section, an outgoing passage that sends liquid from the first liquid reservoir section to the second liquid reservoir section and includes a shared passage shared with the supply passage, a return passage that sends the liquid from the second liquid reservoir section to the first liquid reservoir section, and a controller. After the controller performs a stirring process of stirring the liquid by causing the liquid in the first liquid reservoir section to pass through the outgoing passage and subsequently causing the liquid in the second liquid reservoir section to pass through the return passage, the controller performs a process of flowing out a part of the liquid in the first liquid reservoir section toward the shared passage.

Abstract: Disclosed herein is a liquid ejecting apparatus including: a liquid ejecting head having nozzles that eject a liquid; a plurality of liquid flow passages where the liquid to be supplied to the liquid ejecting head flows; and a heating portion that heats the liquid in the liquid flow passages, in which the liquid flow passages include circulation passages where at least a part of the liquid supplied to the liquid ejecting head is circulated to upstream of the heating portion by being discharged from the liquid ejecting head without passing through the nozzles; and non-circulation passages where the liquid supplied to the liquid ejecting head is not able to be circulated to upstream of the heating portion by being discharged from the liquid ejecting head without passing through the nozzles, and in which the circulation passages are disposed at outer sides of the other liquid flow passages.

Abstract: A liquid ejection apparatus includes: a head including: a nozzle configured to eject liquid; a supply port to which the liquid is continuously supplied; and a recovery port from which the liquid is continuously recovered; a supply flow channel through which the liquid is supplied to the head; and a recovery flow channel through which the liquid is recovered from the head. A flow channel resistance inside the head from the supply port to the nozzle is R_HEAD_IN. A flow channel resistance inside the head from the nozzle to the recovery port is R_HEAD_OUT. A flow channel resistance of the supply flow channel is R_CHANNEL_IN. A flow channel resistance of the recovery flow channel is R_CHANNEL_OUT. The supply and recovery flow channels are laid out so as to satisfy a condition of R_CHANNEL_IN>R_CHANNEL_OUT when R_HEAD_IN>R_HEAD_OUT, or a condition of R_CHANNEL_IN<R_CHANNEL_OUT when R_HEAD_IN<R_HEAD_OUT.

Abstract: An ink jet device includes an ink jet head having a nozzle thorough which ink is discharged, an ink chamber communicating with the nozzle, an ink inlet from which the ink is supplied to the ink chamber, and an ink outlet from which the ink is recovered from the ink chamber, and an ink circulating unit having an ink tank that is in close proximity to the ink jet head and is connected to the ink inlet.

Abstract: An ink jet recording method includes delivering a non-aqueous light-curable ink composition stored in an ink container from the ink container to a head via an ink delivery path and discharging the ink composition from the head toward a recording medium. The non-aqueous light-curable ink composition contains a radically-polymerizable compound and has a surface tension of 25 mN/m or less. The non-aqueous light-curable ink composition stored in the ink container has a dissolved air content of 7 ppm or more. The non-aqueous light-curable ink composition has a dissolved air content of 30 ppm or less at delivery from the ink delivery path to the head.

Abstract: An inkjet printer includes: an inkjet printhead having a first port and a second port; an ink container having an outlet port and a return port; a first ink line interconnecting the first port with the outlet port; a second ink line interconnecting the second port with the return port; an air line connected to the first ink line, the air line having an inlet open to atmosphere; a reversible pump positioned between the second port and the return port for pumping ink in the second ink line; and a dual valve arrangement including: a first valve for selectively controlling ink flow through the first ink line, the first valve being positioned in the first ink line between the ink container and the air line; and a second valve for selectively controlling air flow through the air line.

Abstract: The invention relates to a method for printing a substrate (7) in a printing machine, in which ink is transferred from a flexible carrier (3) to the substrate (7) in accordance with a predefined pattern by energy being introduced into the ink through the flexible carrier (3) by a device for the introduction of energy, some of the ink evaporating in the area of action of the energy and, as a result, a drop of ink (67) being thrown onto the substrate (7) to be printed, this step being repeated at least once, ink being transferred at least partly to the substrate (7) at the same positions in order to intensify the pattern produced. The substrate is transported through the printing machine (1) during the printing and, after the transfer of ink in step (a), the device for the introduction of energy is controlled in such a way that, during the repetition in step (b), the ink is transferred at the same position again as in step (a). The invention further relates to a printing machine for implementing the method.

Abstract: A liquid ejecting apparatus comprising a main tank configured to agitate a liquid accommodated in the main tank; a sub tank configured to receive the liquid supplied from the main tank; heads that eject the liquid supplied from the sub tank; and a liquid supply tube having connector tubes that branch off to the heads respectively; a pump that sucks liquid from the main tank and discharges such liquid to the sub tank; and a valve separated from the pump that operates to allow or restrict flow of the liquid between the main tank and the sub tank. The main ink tank may include a drawer assembly, a portion of which is manually movable to agitate the liquid. The main tank may have a capacity that is greater than that of the sub tank.

Abstract: A microfluid ejection system includes a fluid path having proximate and distal ends, the proximate end having an inlet to receive fluid from a fluid supply, a vacuum chamber for suctioning of air from both the proximate and distal ends of the fluid path, and a pre-ejection chamber disposed in the fluid path between a proximate end and a distal end. The pre-ejection chamber includes a ceiling inclined upward toward each of the proximate and distal ends from a low point to direct air toward either the proximate or distal end for suctioning from the pre-ejection chamber. The microfluid system further includes a first and second air chambers disposed respectively at the proximate and distal ends of the fluid path to receive and direct air to the vacuum chamber.

Abstract: A system for ejecting droplets of a fluid is described. The system includes a substrate having a flow path body that includes a fluid pumping chamber, a descender fluidically connected to the fluid pumping chamber, and a nozzle fluidically connected to the descender. The nozzle is arranged to eject droplets of fluid through an outlet formed in an outer substrate surface. The flow path body also includes a recirculation passage fluidically connected to the descender. The system for ejecting droplets of a fluid also includes a fluid supply tank fluidically connected to the fluid pumping chamber, a fluid return tank fluidically connected to the recirculation passage, and a pump fluidically connecting the fluid return tank and the fluid supply tank. In some implementations, a flow of fluid through the flow path body is at a flow rate sufficient to force air bubbles or contaminants through the flow path body.

Abstract: An apparatus includes an inkjet assembly having inkjet nozzles through each of which ink flows at a nominal flow rate as it is ejected from the nozzle onto a substrate. Ink is held under a nominal negative pressure associated with a characteristic of a meniscus of the ink in the nozzle when ejection of ink from the nozzle is not occurring. The apparatus includes recirculation flow paths, each flow path having a nozzle end at which it opens into one of the nozzles and another location spaced from the nozzle end that is to be subjected to a recirculation pressure lower than the nominal negative pressure so that ink is recirculated from the nozzle through the flow path at a recirculation flow rate.