Abstract: An ink-drop generator (33) of an ink-jet printer is characterized in that a resonating ink cavity (6) from which the ink is supplied via a nozzle plate (39) onto a printing substrate has its lateral walls (7, 8, 9, 10) perpendicular to the nozzle plate (39).

Abstract: One or several jets (14) of an electrically conducting liquid such as ink, are emitted at a given speed Vj and are stimulated so as to form drops (22, 24) at a frequency F, at two break off points (C, L) separated by a distance &Dgr;D less than the wavelength &lgr; of the jet, defined by the relation &lgr;=Vj/F. Two contiguous areas are created (20) in the vicinity of these two break off points (C, L), and the potential of these two areas is brought up to constant electrical potentials with opposite signs (V1, V2). Different quantities of electric charge are thus applied on the drops (22, 24), which are relatively constant even if the break off points should vary. A deflection device (30) then deviates the drops to be recycled (24) and the drops to be printed (22) depending on their charge, which depends on their break off point.

Abstract: The present invention relates to a diaphragm pump comprising an entirely pneumatic control mechanism, which has a double acting jack (18), to which is connected a diaphragm (19), delivery being obtained by the pressurizing of several chambers (15, 16, 17), admission being obtained by the preparation of a first chamber (15), the other chambers (16, 17) being under atmospheric pressure.

Abstract: This invention relates to a continuous multicolor ink jet press comprising a substrate driven by a motor and passing under at least one print head associated with a sensor and supplied by an ink circuit, a synchronization circuit, connected to a process controller and a position encoder placed on the substrate drive motor transmitting a signal to the synchronization circuit, this encoder being a high resolution position encoder. A printing system is located upstream of the printheads and which prints marks regularly on the substrate. These marks are detected by the sensor associated with the printheads.

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: The invention relates to a modulating device for an ink jet printing head comprising a support (1) supporting a gun (3) equipped with a nozzle or discharging the ink jet, means for introducing pressurized ink (21), means for controlling the ink jet associated with the gun (3), ink filtering means, the gun defining a circuit permitting the circulation of the ink introduced into the assembly up to the nozzle. The filtering means (30) tangential filtering means, draining means (22) being provided for the discharge of the unfiltered ink.

Abstract: The invention relates to an ink composition for the marking of objects, specifically nonporous in particular glass bottles having to pass into a bottling chain or line. This ink comprises at least one dye, an organic solvent and a binder incorporating the combination of at least one polymeric resin having hydroxyl or carboxyl functions and a hydrophobic polymeric resin of the epoxy type having a plasticizing effect.The invention also relates to a process for marking objects, using in particular the deflected continuous jet procedure employing said ink, as well as the thus marked substrates.

Abstract: Disclosed is a method to optimize the operation of an ink-jet printer provided with a circuit to collect the ink not used for the printing, comprising a gutter connected to an imperviously sealed ink tank by a conduit placed in a state of depression by a constant flow pump checking the flow rate of ink in the conduit by the measurement of the pressure in the ink tank and controlling the operation of the pump either at its minimum suction rate compatible with efficient collection of the ink or at its maximum suction rate during anomalies of collection.

Abstract: The disclosure relates to a laser marking system, using a displaceable mirror to cause the path of the laser beam to scan in one direction. The mirror is conveniently controlled by at least one flexure hinge driven by a piezo electric device, an electro-strictive device or a magneto-strictive device. In one disclosed embodiment two mirrors (15,16,) are provided, each mirror (15 or 16,) having a flexure hinge device (18,19) individual thereto, and the displacements applied to the flexure hinge devices (18,19,), via respective driving devices (20,21,), cause the mirrors (15,16,) to scan the path of the laser beam (13) in a series of steps in one direction of scan. A computer (11), arranged to drive the flexure hinge driving devices (20,21,), also controls the firing of the laser (12) in accordance with a predetermined program.

Abstract: An accumulating chamber has its fluid pressure regulated between the pressure of a given source pressure value and a discharge pressure value. Electronic control of the accumulating chamber pressure is accomplished by a regulator having a transfer volume and first, second, and third solenoid valves. The transfer volume is connected to the accumulating chamber by the first solenoid valve. The second solenoid valve connects the transfer volume to a pressure source at the given source pressure value. A third solenoid valve connects the transfer volume to open air. A pressure sensor measures the pressure in the accumulating chamber and is connected to an electronic control system.

Abstract: In a liquid projection method and a high-resolution printing device in a vibrationally excited continuous ink-jet printer, an ink jet is divided into drops in the vicinity of a charging device for the electrostatic charging of these drops creating an electrical field that is asymmetrical with respect to the axis of the jet. The method comprises a first step of creating a single microdrop at the upstream end of a main drop by the application of a charging voltage V.sub.M higher than the Rayleigh voltage to the charging device when this main drop appears. Then a second step of deflecting the microdrop to be used for the printing by the application, to the following main drop, of a charging voltage V.sub.c, lower than the voltage V.sub.M and lower than the Rayleigh voltage, that can be modulated as a function of the path chosen for the microdrop towards the printing medium. The charging device can take the form of two half-planes intersecting each other in a direction parallel to the axis of the ink jet.

Abstract: An ink-jet printing machine which has adjacent printing modules. In each printing module, the ink-jet generating device, the ink-drop deflecting device and the collector for collecting the undeflected drops are borne by a single-piece element located on one face of a supporting beam. The opposite face of the supporting beam bears an ink feeding device, and a container to collect the unused ink coming from the collector and the generation device. The deflecting device is mounted in a pivoting manner so that it can be interposed between the generating device and the collector during the printing operation, and can be withdrawn during the maintenance operation.

Abstract: A sealed piston pump having in an open cavity of the pump body, a circular single-piece set formed by a central cylindrical piston. The piston is coupled by a rod to a driving member while the piston in an alternating motion along its longitudinal axis. A ring is placed on the pump body which is hollowed out with an annular channel and a deformable thinned part connecting the piston to the ring. The single-piece set and the pump body are fixedly joined to each other in an imperviously sealed way. The single-block set is made of a synthetic material that is flexible and mechanically and chemically resistant. The pump can be advantageously used in ink-jet printers.

Abstract: An ink jet printing head, particularly intended for printing large characters, includes at least two modulation bodies having respective nozzles fitted with a device for adjusting each of the jets generated by the nozzles. A single module for recovering the ink with only one return line is incorporated in the head. The casing of the head receives, on its face, a support for a cover and, optionally, a second umbilical cover. For printing bar codes, the head provides a cascade sequencing of printed rasters with an increasing order of sequencing of droplets due to a charge voltage. The head is oriented to compensate for the inclination of the raster on the support.

Abstract: An ink circuit particularly intended for pressurizing a pigment ink, for an ink jet printer, is disclosed. The main pressurization line (40) is connected to a first head (9) of a compressor (7), and the depressurization line (45) is connected to a second head (15) of the same compressor (7). Both pressurization and depressurization lines are totally independent from the ink circuits. Magnetic agitators means (3, 4) are provided at the base of the reservoirs (1 and 2) in order to avoid pigment settling. The ink circuit applies to the marking of media or supports, requiring an opaque white ink.

Abstract: In a printing device using m ink jets, a head for the deflection of said jets is made in modular form by the assembling of:a first plurality of elements, each comprising m electrodes,a second plurality of elements for the separation of the elements of the first plurality, that are interposed between certain elements of the first plurality to separate these elements electrically from one another;the elements of the first plurality and of the second plurality being aligned and stacked to form a compact assembly.

Abstract: An acoustic rheometer working in the high frequency range comprises a torsional-mode transducer which is a crystal of the sillenites class, having a height that determines the resonance frequencies of the mode of torsion, and being provided with an electrical excitation means. Furthermore, the sensor is a rod made of an iron/nickel alloy having a very low thermoelastic coefficient. The rod is rigidly connected to the transducer. The respective diameters of the transducer and of the sensor are chosen so that the coefficient of reflection at the transducer/sensor interface is zero. The rheometer can be used in ink-based printing systems.

Abstract: An ink that can be sprayed on an object in jets comprises:(a) zero (plus) to forty percent by mass of one or more metallic salts soluble in a solvent;(b) zero to forty percent by mass of one or more solvents;(c) zero to five percent of one or more organic dyes;(d) zero to ten percent of a polymer;(d) one or more solvents which are more volatile than the solvent or solvents of (b).

Abstract: A device for controlling and regulating a continuous ink jet printer wherein a jet (J) is fractionated into droplets charged in a charge electrode (6) and which then pass between deflection electrodes, a sensor (8) is provided which includes a conductor element (8c) having two parts which are symmetrical with respect to the trajectory of the droplets. The device includes a circuit (9) which determines and processes the first I(t) and second J(t) derivatives with respect to the time of the charge induced in the conductor element (8c) by charged droplets (Gc) in order to determine their speed. The device includes means for regulating the speed of droplets and means for regulating the ink quality.

Abstract: The invention provides a method for checking the printing quality of an ink jet printer. A control frame is printed independently of a marking message. This frame is, for example, formed of 15 dots of which the charge increases from the first to the fifteenth droplet. The distance (G.sub.1, G.sub.2, G.sub.3) separating, respectively, the droplets (1) and (8), the droplets (8) and (15) and the droplets (1) and (15) are permanently maintained so as to correspond to the two relationships: G.sub.1 G.sub.3 =k.sub.1 and G.sub.2 /G.sub.2 =k.sub.2, where k.sub.1 and k.sub.2 are constants.