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: Color printheads in a color inkjet printer are in a fixed order in the scanning carriage, which causes the colors to be printed in a different order when the carriage is scanned in an opposite direction. The different print order may result in a perceptible change in hue between passes in bi-directional printing. Depleted shingle masks are substituted for the nominal ones, based on print direction, at the shingle masking stage, to compensate for print-direction-induced hue shift. A look-up table indexed by a composite color tone value providing a depletion probability and a halftoning error diffusion value are used in determining when depleted shingle masks are to be invoked.

Abstract: A continuous stream ink jet print head has a droplet generator with an elongate cavity for containing the ink, and nozzle orifices in a wall of the cavity for passing ink from the cavity to form jets. The nozzle orifices are disposed at spaced positions along the length of the cavity. An actuator for vibrating the ink in the cavity is provided such that each jet breaks up into ink droplets at the same predetermined distance from the wall of the cavity. The actuator is disposed on the opposite side of the cavity to the wall, includes a vibrator which is divided up along the length of the cavity at least partially into at least two parts, and includes a backing member disposed further from the cavity than the vibrator and secured to and bridging the parts into which the vibrator is at least partially divided. The vibrator is interposed in line between the backing member and the cavity.

Abstract: An improved structure of a liquid drop emitter is provided which works to emit minute drops of liquid to deposit them in a dense array of dots on a substrate to produce a DNA chip, for example. The liquid drop emitter has a plurality of liquid inlets formed in rows in a staggered fashion, thereby allowing the liquid inlets to have a maximum possible area without any physical interference between adjacent two of them and also allowing outlet nozzles to be arranged in a dense array.

Abstract: Methods and apparatus for the deposition of a source material (10) are disclosed. An atomizer (12) renders a supply of source material (10) into many discrete particles. A force applicator (14) propels the particles in continuous, parallel streams of discrete particles. A collimator (16) controls the direction of flight of the particles in the stream prior to their deposition on a substrate (18). In an alternative embodiment of the invention, the viscosity of the particles may be controlled to enable complex depositions of non-conformal or three-dimensional surfaces. The invention also includes a wide variety of substrate treatments which may occur before, during or after deposition. In yet another embodiment of the invention, a virtual or cascade impactor may be employed to remove selected particles from the deposition stream.

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: A spraying control system for an electrically conducting liquid (3) emitted in the form of a pressurized jet (4) through at least one nozzle (2). The system contains apparatus for separating the liquid into drops, apparatus for electrically charging the drops and apparatus for applying an electrical deflection field to the charged drops. The system includes a first (8) and a second (6) monolithic element each with a continuous surface, laid out such that the continuous surfaces are facing each other and define a space (5) between them in which the pressurized jet (4) is emitted through the nozzle (2). The elements (6,8) include apparatus for continuously setting up potentials on the continuous surfaces to obtain the electrical charge of the drops and the electrical deflection field. The system also includes electronic control (31 to 36) for the potentials and apparatus for checking the intensity of electrical currents that can circulate on the continuous surfaces.

Abstract: An ink jet print head for a continuous ink jet printer includes an orifice plate defining an elongated array of ink jet orifices, an ink manifold for supplying ink to the orifices in the orifice plate, and a shear mode piezoelectric transducer mechanically coupled to the orifice plate for vibrating the orifice plate sufficiently uniformly along the length of the array of ink jet orifices to achieve synchronous stimulation. The use of a shear mode piezoelectric transducer eliminates mode cross coupling thereby allowing high frequency stimulation in long ink jet print heads.

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 volumes. 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. Additionally, the apparatus includes a means for improving drop placement on the receiver media. This allows for multiple printing drops per image pixel without loss of image sharpness.

Abstract: The present invention relates to a spotting device for fabricating microarrays of biological materials and a spotting pin inserted therein. More particularly, the present invention is directed to a spotting device, which comprises several pins and pin-guiding holder that allows the pins to move accurately and rectilinearly toward up-down direction by guiding and supporting pins at several points, and spotting pins inserted therein.

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, a means for selectively obtaining droplet coalescence between adjacent droplet streams, and a droplet deflector having a gas source. The ink droplet producing mechanism has at least one physical grouping of nozzles and includes heater positioned proximate to the nozzles. The nozzles in a group are activated in a substantially identical manner. 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 heater may be selectively actuated at a plurality of frequencies to create the stream of ink droplets having the plurality of volumes.

Abstract: Method and apparatus (10, 102) for continuous inkjet printing wherein a first continuous stream of ink droplets (66) traveling above a first flow path (48) is used as a mask for colliding with a second continuous stream of ink droplets (70, 72) traveling along an second, intersecting flow path (56) en route to a receiver (12) on which an image is to be printed. Selective droplets (72) of the second droplet stream are timed and of a size to pass between and avoid the masking droplets (66) of the first droplet stream so as to travel on and impinge the receiver (12) for forming the image thereon. The colliding masking and masked droplets (66, 70) are larger than the selected printing droplets (72) to facilitate collision. The smaller printing droplets (72) facilitate sharp pixel formation. The apparatus is compatible with low voltage CMOS print head systems and provides reliable operation, yet is relatively inexpensive to manufacture compared to other continuous ink jet print head constructions.

Abstract: A printing system having a printhead assembly with an integrated distributive processor for providing localized control of internal printhead processor operations. These internal operations include thermal, energy, firing and timing aspects of the printhead. The printing system includes a controller, a power supply and the printhead assembly. The printhead assembly includes a memory device and distributive integrated processor with an ink driver head.

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 apparatus for printing an image is provided. The apparatus includes a print head with nozzles of differing diameters. This allows multiple printing drop sizes for multi-level printing, thus achieving higher print quality at the same resolution. Additionally, each nozzle is operable to selectively create a stream of ink droplets having a plurality of volumes. 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 print head is formed using a combination of traditional CMOS technology to form the various controlling electrical circuits on a silicon substrate having insulating layer(s) which provide electrical connections to heater elements associated with a nozzle and a MEMS technology for forming ink delivery cavities or channels and bores. A blocking structure is formed in the silicon substrate between an ink channel formed in the silicon substrate and a nozzle bore formed in the insulating layer(s). The blocking structure causes ink in an ink channel to flow around the blocking structure and thereby develop lateral flow components to the liquid entering the bore so that as the stream of fluid emanates from the bore the lateral flow components are a factor in allowing an increased stream deflection under the condition of asymmetric heating.

Abstract: A continuous inkjet apparatus is provided. The apparatus includes a nozzle array with portions of the nozzle array defining a length dimension. A drop forming mechanism is positioned relative to the nozzle array and is operable in a first state to form ink drops having a first volume travelling along a path and in a second state to form ink drops having a second volume travelling along the path. A system applies force to the ink drops travelling along the path with the force being applied in a direction such that the ink drops having the first volume diverge from the path and at least one of the ink drops having the first volume and the second volume are rotated relative to the length dimension. At least a portion of the system is configured to rotate the ink drops relative to the length dimension. The system portion has a cross section and an outlet with the cross section having a first shape and a second shape. The second shape reduces the force along at least a portion of the outlet.

Abstract: A droplet generator for a continuous stream ink jet print head has a cavity for containing ink, and nozzle orifices passing ink from the cavity to form jets. An actuator means vibrates the ink in the cavity such that each jet breaks up into ink droplets. The actuator means is disposed on the opposite side of the cavity to the nozzle orifices, and a surrounding wall of the cavity extends between the actuator means and nozzle orifices for containing the ink therebetween. The surrounding wall has inner and outer constituent wall. The resistive component of the wave impedance of the outer wall passively damps vibration of the inner wall by dissipating its vibration; the reactive component of the wave impedance of the outer wall actively restrains vibration of the inner wall, ensuring that each jet breaks up into ink droplets at the same predetermined distance from its respective nozzle orifice.

Abstract: An ink jet print head is formed of a silicon substrate that includes integrated circuits formed therein for controlling operation of the print head. The silicon substrate has a series of ink channels formed therein along the length of the substrate. An insulating layer or layers overlying the silicon substrate has a series of nozzle openings or bores formed therein along the length of the substrate and each nozzle bore communicates with a respective ink channel. A primary heater element is associated with each nozzle bore for asymmetrically heating the ink in the nozzle bore. A secondary heater element is provided upstream of the primary heater element and formed in the insulating layer to preheat ink just prior to entry of the ink into the nozzle bores.

Abstract: A continuous ink jet print head is formed using a combination of traditional CMOS technology to form the various controlling electrical circuits on a silicon substrate having insulating layer(s) which provide electrical connections to heater elements associated with a nozzle and a MEMS technology for forming ink delivery cavities or channels and bores. A blocking structure is formed in the silicon substrate between an ink channel formed in the silicon substrate and a nozzle bore formed in the insulating layer(s). The blocking structure causes ink in an ink channel to flow around the blocking structure and thereby develop lateral flow components to the liquid entering the bore so that as the stream of fluid emanates from the bore the lateral flow components are a factor in allowing an increased stream deflection under the condition of asymmetric heating.

Abstract: A method for preventing the misdirection of the initial ink droplets discharged from the nozzle of an asymmetric heat-type ink jet printer is provided. The method includes the step of providing power to the heating element that is adjacent to the inkjet nozzle at a higher level than the level normally used during the printing operation. When the power is supplied to the heater in the form of a train of electrical pulses, at least the first electrical pulse has at least one of a greater amplitude, width, or frequency at the beginning of the printing operation than the amplitude, width, and frequency normally used during the printing operation. The method enhances resolution by avoiding the off-target deflection of ink droplets that may happen at the beginning of a printing operation as a result of thermal inertia in the region of the heater and nozzle.

Abstract: A droplet generator for generating a plurality of streams of ink droplets in a continuous ink jet printer comprises a stimulator plate, and the capability of supplying ink to the stimulator plate. The stimulator plate is substantially planar and comprises a substrate, a flexible membrane having a line of nozzles, and an actuator for vibrating the membrane at a resonant frequency. During use, a standing wave is generated such that the line of nozzles is positioned on a locus of uniform vibrational amplitude.

Abstract: An apparatus for treating a substrate is disclosed in which a propellant stream is passed through a channel and directed toward a substrate. Substrate pre-marking or post-marking treatment material is controllably introduced into the propellant stream and imparted with sufficient kinetic energy thereby to be made incident upon a substrate. A multiplicity of channels for directing the propellant and treatment material allow for high throughput, high resolution in-situ treatment. Marking materials and treatment materials may be introduced into the channel and mixed therein prior to being made incident on the substrate, or mixed or superimposed on the substrate without registration. One example is a single-pass, full-color printer.

Abstract: A continuous color ink jet print head (40) for an electronic printing device is composed of a nozzle (42), pressurized ink sources (46, 48), and a print head surface (50) having channels (61, 62, 64, 66) disposed therein such that each channel (61, 62, 64, 66) is in communication with the nozzle (42). The continuous color ink jet print head (40) also includes a microvalve (52, 56) disposed within each of the channels (61, 62, 64, 66) such that each channel (61, 62, 64, 66) is connected through the microvalve (52, 56) to a pressurized ink source (46, 48), thereby permitting ink from the pressurized ink source (46, 48) to flow through the channel (61, 62, 64,66) and thereafter be ejected from the nozzle (42) when the pressurized ink source (46, 48) has attained a particular threshold pressure.

Abstract: A solder jet apparatus is disclosed. The solder jet apparatus is a continuous mode solder jet that includes a blanking system and raster scan system. The use of the raster scan and blanking systems allows for a continuous stream of solder to be placed anywhere on the surface in any desired X-Y plane. This allows for greater accuracy as well as greater product throughput. Additionally, with the raster scan system, repairs to existing soldered surfaces can be quickly and easily performed using a map of the defects for directing the solder to the defects.

Abstract: A droplet generator for a multi-jet CIJ printhead that has an ink chamber with plural orifices for the emission of fluid streams. An actuator drive armature is disposed within the ink chamber and, at one side, has a one-piece solid drive wall with a pair of major faces which are tapered towards one another in the direction away from the other side. At the other side there is only a single pair of transducer mountings disposed adjacent the ends of the drive wall.

Abstract: A technique for sealing a printhead of an ink jet printer system on startup, opening the seal to print, and opening further on an arbitrary path for cleaning, is provided for by the present invention. The ink jet printhead has an ink drop generator, a catcher located adjacent to the ink drop generator, and a catcher pan located below the catcher. An eyelid seals ink within the printhead on startup of the printer system. An actuator mechanism transmits movement to the eyelid along a predetermined non-circular path, having multiple positions for the eyelid. A multiple bar linkage system moves the eyelid along the path.

Abstract: A CIJ printer has a drop generator and a mount. The mounting of the drop generator on the mount is by a pair of fixing screws locating in countersunk screw-threaded bores in the drop generator and disposed in the resilient bushings located in corresponding bores in the mount. To reduce the transfer of ultrasonic vibrations and mounting stresses imposed on the drop generator, two pairs of point contacts protrude between the mount and the drop generator. Each pair being in alignment with the centre of a respective one of the fixing screws and on respective lines perpendicular to a line connecting the centers of the fixing screws.

Abstract: Continuous jetting of liquid metal droplets for deposit on a substrate includes an ejector, a deflection device, a print chute, and a collection reservoir. Liquid metal from a cartridge in the ejector provides a continuous molten material stream through an orifice-defining structure while a vibration device creates a standing wave in the stream to break the molten material stream into individual droplets which receive charge from a charging device. The deflection device enables the positioning of the charged droplets to be controlled for placement on a substrate. Control systems assist in the calibration and control of the continuous stream to ensure that selected droplets are placed at desired locations on the substrate.

Abstract: To compensate for droplet placement errors, a continuous ink jet printer includes a heater having a plurality of selectively independently actuated sections which are positioned along respectively different portions of the nozzle bore's perimeter. An actuator selectively activates none, one, or a plurality of the heater sections such that: actuation of heater sections associated with only a portion of the entire nozzle bore perimeter produces an asymmetric application of heat to the stream to control the direction of the stream between a print direction and a non-print direction, and simultaneous actuation of different numbers of heater sections associated with only a portion of the entire nozzle bore perimeter produces corresponding different asymmetric application of heat to the stream to thereby control the direction of the stream between one print direction and another print direction.

Abstract: An alignment apparatus and method is provided for attaching and aligning components of an ink jet printhead of a continuous ink jet printer. First and second bonding surfaces are provided on first and second components, respectively, of the ink jet printhead. The first and second components are then aligned and attached. The attaching can be accomplished by applying an adhesive, which may also incorporate a chemical accelerator, or by distributing an adhesive from a central region of the bonding surfaces to create an adhesive bond between the first and second bonding surfaces.

Abstract: A continuous ink jet printing system using asymmetrical heating of the fluid in which the nozzle bore (46, 76, 78) of the printhead preferably has a non-circular opening. The nozzle bore (46, 76, 78) has reflection symmetry about the long axis of its cross-section and may be, for example, elliptical or rectangular. In the preferred embodiment of the invention, the nozzle bore (46, 76, 78) has an aspect ratio greater than unity, wherein the aspect ratio is defined as the ratio of the long axis length to the short axis length. A heater (50, 50′, 50″) used to generate deflection of the fluid exiting the nozzle bore (46, 76, 78) generally conforms to the perimeter of the nozzle bore (46, 76, 78) such that the heated portion is along the long dimension of the nozzle bore (46, 76, 78).

Abstract: A method and apparatus for improving inkjet print quality uses a printhead having an array using a plurality of nozzles in sets in each drop generator mechanism. Where a conventional inkjet pen fires a single droplet of ink at a target pixel per firing cycle, the present invention simultaneously ejects a plurality of droplets at different subdivisions of pixels. Drop generators of a printhead array includes a plurality of nozzles for the drop generators arranged such that the light absorption of the sum of the simultaneously ejected ink droplets is like that of conventionally ejected drops but distributed over an area of the printed medium greater than that of a conventional target pixel.

Abstract: A droplet generator for a continuous stream ink jet print head has a cavity (3, 23) for containing the ink; nozzle orifices (17, 27) in a wall (9) of the cavity (3, 23) for passing the ink from the cavity (3, 23) to form jets; and first (11, 21) and a second (13, 25) actuator device for establishing in combined operation a travelling wave. The travelling wave travels from the fist actuator device (11, 21) through the ink to the second actuator device (13, 25) and passes in a direction substantially parallel to the wall (9) containing the nozzle orifices (17, 27).

Abstract: A stroke based method for printing for use in a continuous ink jet printer. A set number of drops are assigned to a stroke, but the number of positions which can be printed on a stroke is greater than the number of drops on the stroke. This allows improved fonts at the same print speed.

Abstract: A continuous jet module, apparatus, and method are described for printing with a high viscosity printing fluid having a viscosity of 10 to 100 centipoise. The module includes a housing having a printing fluid reservoir for feeding the high viscosity printing fluid to a plurality of channels. The reservoir has a first longitudinal direction and includes a plurality of openings in a second direction. Each channel is disposed in one of the corresponding openings, and each channel receives the high viscosity printing fluid from the reservoir through its corresponding opening and generates therefrom a continuous jet of high viscosity printing fluid.

Abstract: A droplet generator and ink jet printhead assembly employing the droplet generator are disclosed. The droplet generator can operate with a wide range of fluids over a wide range of conditions, is easily serviced, and can be easily integrated into a machine such as a Three Dimensional Printing machine. The assembly includes a nozzle having an orifice, a liquid reservoir or supply for containing a liquid to be emitted from the nozzle and a non-resonant elastically deformable fluid conduit for conveying the liquid from the liquid reservoir to the nozzle. A transducer is disposed in abutting relation with the fluid conduit a predetermined distance from the nozzle. The transducer is energized by a suitable electrical signal, such as a sinusoidal signal. The transducer causes compression of the conduit and provides a wave which propagates along the fluid conduit and fluid contained therein toward the nozzle and orifice.

Abstract: An ink jet printing device is disclosed in which a bore providing a nozzle for the ejection of droplets of ink is closed by a pin to prevent ejection of ink. The pin is movable into a retracted position in which the pin is withdrawn from the bore to permit ejection of droplets of ink from an ink chamber in communication with said bore. The pin is connected to a piston movable within a chamber. A spring acts on the piston to urge the pin into the bore. Withdrawal of the pin from the bore is effected by pressure of ink acting, against the spring force, on the piston. Ink is supplied selectively under pressure to the ink chamber from an ink supply. Alternatively the piston may be moved by selective application of positive and negative gaseous pressure in the chamber.

Abstract: The method for synchronizing the plurality of piezoelectric crystals on a corresponding plurality of ink jet printheads comprises the steps of: (a) coupling the plurality of printheads together in a daisy-chain configuration, (b) embedding a first clock signal in data; (c) transmitting the data to the printheads on the daisy-chain; (d) each of the printheads receiving the data; (e) each of the printheads deriving a second clock signal from the data received, which is directly proportional to the first clock signal; and (f) each of the printheads driving its corresponding piezoelectric crystal with the second clock signal. Accordingly, all of the piezoelectric crystal clock sources will be synchronized in frequency with each other, eliminating beat frequency drift errors between the printheads.

Abstract: A continuous jet module for discharging a high viscosity printing fluid and apparatus which includes a plurality of the printing modules is provided. The module includes a housing having a printing fluid reservoir for storing and providing said high viscosity printing fluid and a plurality of channels. The reservoir has a first longitudinal direction and includes a plurality of openings in a second direction. Each channel is disposed in one of the corresponding openings and each channel receives the high viscosity printing fluid from the reservoir through its corresponding opening and generates therefrom a continuous jet of high viscosity printing fluid.

Abstract: A graphic arts printing apparatus includes a delivery channel for hydrophobic liquid; a source of pressurized hydrophobic liquid communicating with the delivery channel; a nozzle bore which opens into the delivery channel to establish a continuous flow of hydrophobic liquid in a stream; and a droplet generator which causes the stream to break up into a plurality of droplets at a position spaced from the stream generator. The droplet generator includes a heater having a selectively-actuated section associated with only a portion of the nozzle bore perimeter, whereby actuation of the heater section produces an asymmetric application of heat to the stream to control the direction of the stream between a print direction and a non-print direction.

Abstract: A device permitting the emission or discharge of material in the form of a jet by a nozzle, which is able to communicate with a cavity of the device through which the material passes and where it is pressurized in order to permit the formation of the jet under the effect of a controller. A stimulator is located in the vicinity of the nozzle in order to split up the jet into a succession of elements. The device includes a seal for the nozzle when no material jet is being discharged made of a deformable member placed between the stimulator and the nozzle and designed and positioned so as to seal the nozzle when the controller does not allow the emission of a material jet and to free the nozzle when the controller allows the emission of a jet.

Abstract: A continuous-jet type ink jet printer has a full-line type printing head with high reliability for forming ink particles and which is capable of reducing noise. An ink particle forming section includes a rotary drum having an ink-supply hole and a plurality of ink-jet holes, which are arranged on an outer circumferential face. A housing rotatably accepts the rotary drum. A slit mechanism is provided in the housing through which the ink passes to form ink particles for printing on paper. An ink control section controls jet courses of the ink particles. A paper table for supporting the paper is disposed to face the ink particle forming section and a conveyor conveys the paper onto the paper table.

Abstract: An armature (1) for an actuator drive for a multi-jet continuous ink jet printhead has, at one side, a row of transducer mountings (10). The armature (1) has a plurality of elongate slots (5) therethrough in a row parallel to the one side, each slot (5) extending away from the one side and being aligned intermediate to the transducer mountings (10), whereby lands (6) between the slots (5) are aligned with the transducer mountings (10).

Abstract: Disclosed is a process which comprises reacting a polyimide precursor with borane. Also disclosed is a thermal ink jet printhead containing a layer comprising the product of this reaction.

Abstract: A continuous ink jet printing system for use with a hot-melt ink, comprising a supply chamber for retaining said ink in a liquid form, means for applying heat to the ink in said chamber to maintain said ink in a liquid form, means for conveying said ink in liquid form from said chamber to a printhead for projection toward a substrate to be marked, catcher means for collecting any of said ink that is not directed to said substrate, means for returning the collected ink as a liquid to the supply chamber, and means for maintaining the ink as a liquid while it is being returned to said supply chamber.Also disclosed is an ink jet nozzle for use in printing hot-melt inks at elevated temperatures comprising an ink jet nozzle body, a transducer, means for acoustically coupling said transducer to said body, and means for maintaining said transducer acoustically coupled to said body at elevated temperatures.

Abstract: An apparatus is provided for locking an ink jet resonator assembly into a printhead of a continuous ink jet printer. The locking apparatus comprises a resonator holder for holding the resonator prior to alignment of the resonator assembly; a frame for supporting the resonator holder and the resonator assembly after alignment; and a methyl-cyanoacrylate adhesive applied between the resonator holder and the frame to lock into position the properly aligned resonator assembly.

Abstract: A pump (1) has a rotor (4) and a stator (3) disposed closely adjacent to and biased towards it, but spaced apart from a surface of the rotor. The stator (3) or rotor (4) has recesses (30) on its surface facing the rotor or stator respectively, and an inlet to and an outlet from each recess to provide for the supply of fluid to and from the recess. Rotation of the rotor (4) about its axis is arranged to cause fluid to be pumped from the inlet to the outlet as a result of the viscous drag on the fluid resulting from rotation of the rotor relative to the stator (3). The force biasing the rotor (4) and stator (3) together is provided at least in part by fluid pressure feedback from the pump (1) in order to control the clamping or biasing pressure between the rotor and stator automatically.

Abstract: A mounting apparatus holds in position a droplet generator assembly to be mounted in a continuous ink jet printing system. The droplet generator assembly comprises a pair of conical slots and a pair of conical apertures, located on opposing sides of the droplet generator. A resonator clamping plate includes a plurality of mating protrusions. A resonator support includes a plurality of spherical protrusions. A holding force, such as a screw, securely holds the assembled structure. The clamp and support interact with the conical slots and apertures to locate and exactly constrain the droplet generator. With the mounting structure of the present invention, the six degrees of freedom of adjustment are controlled.

Abstract: An .Iadd.acoustically soft .Iaddend.ink jet nozzle .?.assembly is produced from materials, such as.!. .Iadd.for continuous jets. The nozzle is a tubular member formed from .Iaddend.polyphenylene sulfide.?.. The resulting assembly is acoustically soft so that undesirable fluid and mechanical resonances are.!. (.Iadd.RYTON) which has a .Iaddend.substantially .?.attenuated.!. .Iadd.constant response over a transducer range of 10-100 KHz.Iaddend..