Abstract: A method of controlling an inkjet printhead containing a substantially closed duct in which ink is situated, said duct having at least one exit opening for the ink, wherein an actuation pulse is applied to an electro-mechanical transducer so that the pressure in the duct changes in such a manner than an ink drop is ejected from the exit opening, wherein the method further comprises: measuring the electric impedance of the electromechanical transducer and adapting the actuation pulse on the basis of the measured impedance.

Abstract: An inkjet printhead having a plurality of pressure chambers each of which is fluidly connected on the one hand, via an ink supply path, to a common ink reservoir and on the other hand to a nozzle, wherein an actuator is provided for each pressure chamber for pressurizing the ink contained therein so as to eject an ink droplet through the nozzle in accordance with a print signal, and an acoustic wave attenuator is arranged to control the acoustic reflection and transmission properties of the ink supply path.

Abstract: A method for improved controlling of an ink jet printer includes measuring the amount of ink dosed to at least one printhead of the ink jet printer, measuring the amount of ink droplets released by at least one nozzle of the printhead, and determining the amount of a ink contained by the printhead by using the amounts measured. A computer program and a computer running the computer program are adapted to carry out the method. Moreover, an ink jet printer is adapted to perform the method.

Abstract: A method of determining the average droplet size of ink droplets released by an ink jet printer. Controlling the droplet speed and droplet size within an ink jet printer is important for maintaining print quality and reliability of the jetting process itself. The invention also relates to an ink jet printer adapted for performing the present method.

Abstract: A method of preparing an inkjet printhead, prior to generating an image onto a receiving medium, the printhead containing a substantially closed ink duct comprising an inlet opening and a nozzle, said duct being operationally connected to an electro-mechanical transducer, the method including the steps of arranging that the duct is filled with ink; generating a pressure wave in the ink, the pressure wave causing a deformation of the transducer which generates an electrical signal as a result; analyzing the electrical signal, and deciding on the basis of the analysis whether the inkjet printhead is ready to proceed with the printing of the image. The inkjet printer is also modified to perform the present method.

Abstract: A printing method for application in an inkjet printer containing a substantially closed ink chamber and a nozzle, said ink chamber being operationally connected to an electro-mechanical converter, which includes the steps of printing an image for the purposes of which the converter is actuated according to a predetermined printing strategy in order to eject ink drops from the nozzle for the formation of the image onto a carrier; detecting the presence of an obstruction, in particular a gas bubble, inside the ink chamber during printing: interrupting the printing process: modifying the printing strategy in such a way that the obstruction will not produce ink chamber failure while the process of printing the image continues by actuating the converter using the modified printing strategy: and continuing the printing process by application of the modified printing strategy. An inkjet printer which has been modified for using the present method is also provided.

Abstract: A method and system for application in an inkjet printer containing a substantially closed ink duct in which ink is situated, said duct being operationally connected to an electromechanical transducer, the method including the steps of: actuating the transducer with a number of actuation pulses according to a predetermined actuation setting in order to eject ink drops from a duct nozzle, where a pressure wave is generated in the duct by an actuation pulse, this pressure wave causing a deformation of an electromechanical transducer which generates an electrical signal; analyzing the electrical signal; analyzing the signal for a plurality of different actuation settings, and based on which analysis, determining an actuation setting, on the one side of which setting the ejection of a drop is a stable process and on the other side of which setting, the ejection of a drop is an unstable process.

Abstract: A printing method for use with an inkjet printer containing a substantially closed ink duct including a nozzle, said duct being operationally connected to an electro-mechanical transducer, the presence of an air bubble in the duct is determined and the air bubble is subsequently eliminated, wherein the elimination of the air bubble takes place by actuating the transducer at a frequency which is lower than the frequency that corresponds to the size of the air bubble in equilibrium, and the amplitude is sufficient to arrange for the ink drops to be ejected from the nozzle. The invention also relates to an inkjet printer which has been modified to use the present method.

Abstract: A scanning type printing device is capable of operating in a multiple printing stage mode. When operating in a multiple printing stage mode, this printing device is controlled such upon receipt of a delay signal, further printing is executed, but only during the stroke of the image-receiving member, whereon printing is in progress until the image portion associated with that stroke is completely printed. This is done in order to overcome or at least reduce gloss variations in a printed image when printing in progress is temporarily interrupted.

Abstract: A printing device with at least one bi-directional scanning print head can print images on an image-receiving member in multiple traverses. After each traverse, the image-receiving member is displaced with respect to the print head in the sub scanning direction over a predetermined displacement distance. By selecting for each traverse of the print head an active portion thereof taking account of the displacement step between subsequent traverses, on substantially each position of the image-receiving member, the traversing direction of the print head is the same for each first exposure to an active portion of the traversing print head.

Abstract: A method of controlling an inkjet printhead with a substantially closed duct in which ink is disposed, which duct has an exit opening for the ink, the method including the actuation of an electromechanical transducer so that the pressure the duct changes in such a manner that an ink drop is ejected from the exit opening, said pressure causing a deformation of the transducer, whereby after the end of the actuation, an electric signal generated by the transducer is measured as a result of the deformation, wherein a subsequent actuation of the transducer is adapted to the measured signal.

Abstract: A method of controlling an inkjet printer containing at least two substantially closed ducts in which ink is present, which includes actuating an electro-mechanical transducer whereby the pressure in a first duct is increased, and a pressure change in another duct is also generated by said actuation, whereby an electro-mechanical transducer is deformed as a result of the pressure change, said electrical transducer generating an electrical signal, and measuring the electric signal.

Abstract: An inkjet printhead having a plurality of pressure chambers each of which is fluidly connected on the one hand, via an ink supply path, to a common ink reservoir and on the other hand to a nozzle, wherein an actuator is provided for each pressure chamber for pressurizing the ink contained therein so as to eject an ink droplet through the nozzle in accordance with a print signal, and an acoustic wave attenuator is arranged to control the acoustic reflection and transmission properties of the ink supply path.

Abstract: A method of controlling an inkjet printer containing at least two substantially closed ducts in which ink is present, which includes actuating an electro-mechanical transducer whereby the pressure in a first duct is increased, and a pressure change in another duct is also generated by said actuation, whereby an electro-mechanical transducer is deformed as a result of the pressure change, said electrical transducer generating an electrical signal, and measuring the electric signal.

Abstract: A method of controlling an inkjet printhead containing a substantially closed duct in which ink is situated, said duct having at least one exit opening for the ink, wherein an actuation pulse is applied to an electro-mechanical transducer so that the pressure in the duct changes in such a manner than an ink drop is ejected from the exit opening, wherein the method further comprises: measuring the electric impedance of the electromechanical transducer and adapting the actuation pulse on the basis of the measured impedance.

Abstract: An actuating device for a multi-nozzle ink jet printhead, which includes a linear array of electromechanical transducers some of which are configured as actuator fingers associated with the nozzles of the printhead while others are configured as support fingers disposed between the actuator fingers, wherein each transducer has a first and a second electrode and is adapted to expand and contract in accordance with a voltage applied between the first and second electrodes, wherein the totality of the transducers consists of at least one group which includes a plurality of actuator fingers and a plurality of support fingers, and control circuit are associated with each group for applying a voltage that depends on the number of active actuator fingers in this group, to the first electrodes of all support fingers of the group.

Abstract: A method of controlling an inkjet printhead with a substantially closed duct in which ink is disposed, which duct has an exit opening for the ink, the method including the actuation of an electromechanical transducer so that the pressure the duct changes in such a manner that an ink drop is ejected from the exit opening, said pressure causing a deformation of the transducer, whereby after the actuation, an electric signal generated by the transducer is measured as a result of the deformation, wherein a subsequent actuation of the transducer is adapted to the measured goal.

Abstract: A melting device for melting an ink unit used in an inkjet printer, including a melting chamber provided with a wide end for dispensing the ink unit to the melting chamber and a narrow end, the melting chamber having a form such that the ink unit moves, as a result of melting, in a direction from the wide end to the narrow end, the ink unit being laterally enclosed with respect to said direction by one or more walls of a melting chamber, wherein the walls which form a lateral enclosure for the ink unit are heated, during the melting, to above a temperature at which the ink is liquid.

Abstract: An actuating device for a multi-nozzle ink jet printhead, which includes a linear array of electromechanical transducers some of which are configured as actuator fingers associated with the nozzles of the printhead while others are configured as support fingers disposed between the actuator fingers, wherein each transducer has a first and a second electrode and is adapted to expand and contract in accordance with a voltage applied between the first and second electrodes, wherein the totality of the transducers consists of at least one group which includes a plurality of actuator fingers and a plurality of support fingers, and control means are associated with each group for applying a voltage that depends on the number of active actuator fingers in this group, to the first electrodes of all support fingers of the group.

Abstract: An ink-jet system has an ink channel between an ink reservoir and a nozzle, and an electromechanical transducer which comprises an expansible member arranged adjacent to the ink channel for abruptly reducing the volume of the ink channel in order to eject an ink droplet through the nozzle. The depth of a portion of the ink channel between the expansible member and the nozzle is larger than both the depth of the portion adjacent to the expansible member and the height of the nozzle.