Abstract: An ink jet printing device includes a pressure chamber, a first actuator membrane being arranged to form a first flexible wall of the pressure chamber, a first piezo-electric part being operatively connected to a surface of the first actuator membrane, a second actuator membrane being arranged to form a second flexible wall of the pressure chamber and a second piezo-electric part being operatively connected to a surface of the second actuator membrane, wherein the second flexible wall is mechanically decoupled from the first flexible wall.

Abstract: A method of forming an array of piezoelectric actuators on a membrane (18) which includes the steps of preparing a piezoelectric comb-like structure having an array of islands that are integrally connected by a continuous top portion and that form piezoelectric layers of the actuators, the islands having an electrode at a bottom side, attaching the comb-like structure with its bottom electrode to a surface of the membrane, removing the continuous top portion of the comb-like structure to thereby separate the actuators from one another, and forming top electrodes on the top surfaces of the piezoelectric layers of the actuators.

Abstract: A print head comprises a pressure chamber in fluid communication with a nozzle and an actuator structure in operative communication with the pressure chamber for generating a pressure wave in the pressure chamber. The actuator structure comprises a membrane, wherein a first surface of the membrane forms a flexible wall of the pressure chamber and a piezo actuator, wherein the piezo actuator is arranged on a second surface of the membrane, the second surface being opposite of the first surface, such that the membrane is deformed at the position of the piezo actuator upon actuation of the piezo actuator. In the print head, the membrane is pivotably clamped between a first structure layer and a second structure layer such that the membrane pivots at the location of clamping upon deformation of the membrane due to actuation of the piezo actuator.

Abstract: A droplet ejection device comprising a flow passage, a nozzle orifice formed in a wall of the flow passage, a circulation system for circulating a liquid through the flow passage, and an actuator system for generating a pressure wave in the liquid in the flow passage, wherein an obstruction member is arranged in the flow passage in a position opposite to the nozzle orifice and projecting towards the nozzle orifice.

Abstract: An ink jet printing device includes a pressure chamber, a first actuator membrane being arranged to form a first flexible wall of the pressure chamber, a first piezo-electric part being operatively connected to a surface of the first actuator membrane, a second actuator membrane being arranged to form a second flexible wall of the pressure chamber and a second piezo-electric part being operatively connected to a surface of the second actuator membrane, wherein the second flexible wall is mechanically decoupled from the first flexible wall.

Abstract: An ink supply assembly includes at least one inlet port. At least one outlet port is connected to the inlet port via an ink cavity and is adapted to be connected to an ink discharge unit of an ink jet device. The ink supply assembly has a sandwich structure formed by at least two plate members and a foil that is interposed therebetween and has a part forming a wall of said ink cavity. At least one of the plate members defines a pressure equalization chamber adjacent to the ink cavity and separated therefrom by the foil.

Abstract: A method of manufacturing a piezoelectric ink jet device having a pressure chamber, a flexible membrane delimiting the pressure chamber, a piezoelectric actuator mounted on the membrane, and a rigid substrate attached to the side of the membrane carrying the actuator, which includes the steps of providing the piezoelectric actuator with an electrode on at least one side, attaching the actuator with its electrode side to a carrier plate, bonding the rigid substrate to the side of the carrier plate carrying the actuator, and removing material from the carrier plate on the side opposite to the actuator and leaving only a thin layer of the carrier plate which then forms the membrane.

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: An electrostatic inkjet head providing high pressure to ink in order to enable high quality printing. The electrostatic actuator providing the pressure to the membrane (200) compressing the ink in a chamber (50) with an opening (20) is characterized by an overlapping area of the actuation electrode (300) and the moveable electrode (500) not determined by the area of the membrane (200) covering the chamber (50) with the ink. The maximum pressure that can be applied can be adapted by means of the ratio of the overlapping area (220) of the two electrodes and the area (210) of the membrane (200) covering the chamber (50) with the ink. Use of said head to eject a liquid drug used in an injection system.

Abstract: A piezoelectric actuator having a bottom electrode attached to a membrane, a piezoelectric layer on the bottom electrode, and a top electrode formed on the piezoelectric layer, wherein the bottom electrode extends substantially over the entire bottom surface of the piezoelectric layer, and at least a peripheral portion of a top surface of the piezoelectric layer and side faces of that layer are covered with an insulating layer, and wherein in the peripheral portion of the top surface of the piezoelectric layer the top electrode is superposed on the insulating layer.

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: An electrostatic inkjet head providing high pressure to ink in order to enable high quality printing. The electrostatic actuator providing the pressure to the membrane (200) compressing the ink in a chamber (50) with an opening (20) is characterized by an overlapping area of the actuation electrode (300) and the moveable electrode (500) not determined by the area of the membrane (200) covering the chamber (50) with the ink. The maximum pressure that can be applied can be adapted by means of the ratio of the overlapping area (220) of the two electrodes and the area (210) of the membrane (200) covering the chamber (50) with the ink. Use of said head to eject a liquid drug used in an injection system.

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 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: An ink supply assembly includes at least one inlet port. At least one outlet port is connected to the inlet port via an ink cavity and is adapted to be connected to an ink discharge unit of an ink jet device. The ink supply assembly has a sandwich structure formed by at least two plate members and a foil that is interposed therebetween and has a part forming a wall of said ink cavity. At least one of the plate members defines a pressure equalization chamber adjacent to the ink cavity and separated therefrom by the foil.

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 of forming an array of piezoelectric actuators on a membrane (18) which includes the steps of preparing a piezoelectric comb-like structure having an array of islands that are integrally connected by a continuous top portion and that form piezoelectric layers of the actuators, the islands having an electrode at a bottom side, attaching the comb-like structure with its bottom electrode to a surface of the membrane, removing the continuous top portion of the comb-like structure to thereby separate the actuators from one another, and forming top electrodes on the top surfaces of the piezoelectric layers of the actuators.

Abstract: A method of manufacturing a piezoelectric ink jet device having a pressure chamber, a flexible membrane delimiting the pressure chamber, a piezoelectric actuator mounted on the membrane, and a rigid substrate attached to the side of the membrane carrying the actuator, which includes the steps of providing the piezoelectric actuator with an electrode on at least one side, attaching the actuator with its electrode side to a carrier plate, bonding the rigid substrate to the side of the carrier plate carrying the actuator, and removing material from the carrier plate on the side opposite to the actuator and leaving only a thin layer of the carrier plate which then forms the membrane.

Abstract: A piezoelectric actuator having a bottom electrode attached to a membrane, a piezoelectric layer on the bottom electrode, and a top electrode formed on the piezoelectric layer, wherein the bottom electrode extends substantially over the entire bottom surface of the piezoelectric layer, and at least a peripheral portion of a top surface of the piezoelectric layer and side faces of that layer are covered with an insulating layer, and wherein in the peripheral portion of the top surface of the piezoelectric layer the top electrode is superposed on the insulating layer.

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 the strip of the image-receiving member, whereon printing is in progress until the image portion associated with that strip 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.