Abstract: A substrate (10; 110; 210; 310) for an ink jet printhead comprising: at least three slots (12a, 12b, 12c) of elongated shape, oriented parallel to one another lengthwise in a vertical direction (13); three corresponding actuating banks (16a, 16b, 16c); a plurality of drive circuits (18); and a plurality of terminals (21, 21a, 21b), lesser in number than the ejection actuators (16), connected to the drive circuits (18) for receiving external signals, wherein at least two (12a, 12b) of the three slots are arranged side by side along the respective long edges in an upper portion (10a) of the substrate, and the third slot (12c) is arranged in a lower portion (10b) of the substrate, and wherein moreover the terminals (21) connected to the drive circuits are arranged in a line along the edges (11a, 11b) of the substrate (10) parallel to the slots and therefore to this given vertical direction (13). This substrate has a robust structure and is less likely to crack in the zone of the slots.

Abstract: A method for manufacturing an ejection head (10) or ejector suitable for ejecting in the form of droplets (16) a liquid (14) conveyed inside the ejection head (10), comprising a step of producing, from a silicon wafer, a nozzle plate (12) having at least one ejection nozzle (13); a step of producing, from another silicon wafer, a substrate (11) having at least one actuator (15) for activating the ejection of the droplets of liquid through the nozzle (13); and a step of joining the nozzle plate (12) and the substrate (11) together to form the ejection head, wherein this joining step comprises the production of a junction (25), made by means of the anodic bonding technology, between the substrate (11) and the nozzle plate (12), in such a way that, in the area of this junction (25), the ejection head (10) does not present structural discontinuities, and also possesses a resistance to chemical corrosion by the liquid (14) contained in the ejection head (10) at least equal to that of the silicon constituting both

Abstract: A monolithic thermal ink jet printhead (40) comprising a groove (45), a plurality of chambers (74) and nozzles (56) is manufactured by means of steps of: (203, 205) partially etching the groove (45) by means of a “dry” process and a “wet” process; (210) depositing a plurality of sacrificial layers (54); (212) obtaining a plurality of casts (156); (216) completing the etching of the groove (45) by means of an electrochemical process; and (220) removing the casts (156) and the sacrificial layers (54) in such a way as to obtain a plurality of nozzles (56) and chambers (74).

Abstract: A thermal ink jet printhead (40) for the emission of droplets of ink on a print medium (46) comprises a reservoir (103) containing ink (142), a die (61), a slot (102) engraved in said die (61) and a plurality of ejectors (73), each of which in turn comprises a chamber (74), a resistor (27) and a nozzle (56), each of said chambers (74) being put in fluid communication with said slot (102) through a plurality of elementary ducts (72) lying on a different plane from the bottom (67) of said chamber (74).

Abstract: A thermal ink jet printhead (40) for the emission of droplets of ink on a print medium (46) comprises a reservoir (103) containing ink (142), a die (61), a slot (102) engraved in said die (61) and a plurality of ejectors (73), each of which in turn comprises a chamber (74), a resistor (27) and a nozzle (56), each of said chambers (74) being put in fluid communication with said slot (102) through a plurality of elementary ducts (72) lying on a different plane from the bottom (67) of said chamber (74).

Abstract: A monolithic thermal ink jet printhead (40) comprising a groove (45), a plurality of chambers (74) and nozzles (56) is manufactured by means of steps of: (203, 205) partially etching the groove (45) by means of a “dry” process and a “wet” process; (210) depositing a plurality of sacrificial layers (54); (212) obtaining a plurality of casts (156); (216) completing the etching of the groove (45) by means of an electrochemical process; and (220) removing the casts (156) and the sacrificial layers (54) in such a way as to obtain a plurality of nozzles (56) and chambers (74).

Abstract: A thermal ink jet printhead (40) for the emission of drops of ink on a print medium (46) comprises a tank (103) containing ink (142), a lamina (67), a groove (45) and a plurality of ejectors (73), each of which comprises in turn a chamber (74) placed laterally with respect to the groove (45), and fluidly connected thereto by means of a plurity of elementary ducts (75) produced on said lamina (67).

Abstract: A method for manufacturing an ejection head (10) or ejector suitable for ejecting in the form of droplets (16) a liquid (14) conveyed inside the ejection head (10), comprising a step of producing, from a silicon wafer, a nozzle plate (12) having at least one ejection nozzle (13); a step of producing, from another silicon wafer, a substrate (11) having at least one actuator (15) for activating the ejection of the droplets of liquid through the nozzle (13); and a step of joining the nozzle plate (12) and the substrate (11) together to form the ejection head, wherein this joining step comprises the production of a junction (25), made by means of the anodic bonding technology, between the substrate (11) and the nozzle plate (12), in such a way that, in the area of this junction (25), the ejection head (10) does not present structural discontinuities, and also possesses a resistance to chemical corrosion by the liquid (14) contained in the ejection head (10) at least equal to that of the silicon constituting both

Abstract: A process for manufacturing a monolithic thermal ink jet printhead (40) comprising a plurality of chambers (74) and of nozzles (56), comprises steps of (206) depositing a plurality of sacrificial layers (31), of obtaining, by means of exposure and development operations, a plurality of casts (156), of (215) applying a structural layer (107), and subsequently steps of (225) removing the casts (156) and of (226) removing the sacrificial layers (31), in order to produce a plurality of chambers (74) and nozzles (56).

Abstract: This invention relates to an integrated printhead (20) for ink jet printers, wherein the addressing of the various nozzles is effected in at least 3-D mode. The head (20) comprises a plurality of groups (24) of ink jet elements (21, 22) arranged in M rows and L columns wherein, in particular, the selection and activation of the different columns L are performed, under the control of an external drive circuit, by means of logic circuits (25) inside the head itself (20). The head (20) is advantageous with respect to the known art in that it does not require control of the L columns under critical conditions such as highly variable electric currents with very high peak values.

Abstract: A thermal ink jet printhead (40) for the emission of droplets of ink on a print medium (46) comprises a reservoir (103) containing ink (142), a die (61), a slot (102) engraved in said die (61) and a plurality of ejectors (73), each of which in turn comprises a chamber (74), a resistor (27) and a nozzle (56), each of said chambers (74) being put in fluid communication with said slot (102) through a plurality of elementary ducts (72) lying on a different plane from the bottom (67) of said chamber (74).

Abstract: The single heads (40) mounted on a single print carriage of an ink jet printer comprise a column (50) of phototransistors (51-i), built directly into the chip of each head in the same process steps as used for the circuits for selecting and driving the actuating resistors; an illuminating device (43) on board the printer focuses a light spot (70) on the column (50) of phototransistors (51-i) which, scanned in sequence, provide the electronic controller of the printer a video output (57); from the output (57), processing and computing means produce a measurement of the vertical and horizontal misalignment of each head (40), a measurement used subsequently to automatically compensate this misalignment.

Abstract: This invention relates to a printhead in which a plurality of resistors are selectively activated by an external control circuit to produce the ejection of droplets of ink through nozzles located in correspondence with the resistors. Selection and activation are performed according to a matrix having a plurality of vertical lines corresponding to the number of resistors (1) per group of nozzles and a plurality of horizontal lines corresponding to the number of groups of nozzles (P) in the head. The groups of nozzles (P) in the polychromatic head comprise real nozzles ( 1, 27, 53, 79, 131, 157, 183, 235, 261, 287) and fictitious nozzles (105, 209), as a result of which the groups of nozzles have a regular layout, and are uniformly distributed and equivalent to the corresponding layout of a monochromatic head. With this solution, polychromatic heads having the same number and the same disposition of contacts with the external circuit and the same height as a monochromatic head can be manufactured simply.

Abstract: An actuator assembly (81) for ink jet printheads, both monochromatic and colour, with a large number of nozzles (62), consists of a die (58) stuck on a rigid substrate (166) and divided into two parts lengthwise to permit the flow of ink from the tank to the nozzles (62), and a flat cable (130) with nozzles (62) stuck on the die (58); the actuator assembly (81) is produced by means of the operations of sticking the die (58) on the rigid substrate (166), making a through cut (173) along the entire length of the die (58), sticking the flat cable (130) with nozzles (62) on the die (58) and sealing the ends of the longitudinal cut (173) with glue. The object of the actuator assembly (81) and the relative manufacturing process is to prevent particularly long dice from breaking during manufacture of the head.

Abstract: An actuator assembly (81) for ink jet printheads, both monochromatic and color, with a large number of nozzles (62), consists of a die (58) stuck on a rigid substrate (166) and divided into two parts lengthwise to permit the flow of ink from the tank to the nozzles (62), and a flat cable (130) with nozzles (62) stuck on the die (58); the actuator assembly (81) is produced by means of the operations of sticking the die (58) on the rigid substrate (166), making a through cut (173) along the entire length of the die (58), sticking the flat cable (130) with nozzles (62) on the die (58) and sealing the ends of the longitudinal cut (173) with glue. The object of the actuator assembly (81) and the relative manufacturing process is to prevent particularly long dice from breaking during manufacture of the head.

Abstract: In a thermal ink jet printhead, an emission resistor includes a layer of electrically conductive material for making connections to the resistor. A temperature sensor and a reference temperature sensor, provided for detecting the temperature of enucleation of a bubble and used to directly determine the amount of energy needed for the emission resistor to effectively reach the temperature of enucleation, are arranged in correspondence with an integrated test resistor identical in construction to the emission resistor. The temperature sensor is formed from the layer of electrically conductive material. A differential amplifier having inputs connected to the temperature sensor and the reference temperature sensor effects regulation of a variable duration of pulses applied to the emission resistor.

Abstract: The individual monochromatic printheads mounted simultaneously on the scanning carriage of an ink jet printer are provided with an opto-electronic position detector of the four-quadrant type, which is integrated directly in the chip of each head by means of the same MOS technology used for the circuits for selection and driving of the emission resistors; an illumination device fixed onto the printer focuses a light spot on the position detector which thus provides the electronic control unit of the printer with a measurement of both the vertical and horizontal misalignment of each head, a measurement which is subsequently used in order to compensate automatically for the misalignment thereof.

Abstract: In a thermal ink jet print head the ink is expelled in the form of small drops through a plurality of nozzles communicating with corresponding expulsion chambers for expulsion of the ink through the effect of rapid heating of heater elements contained in the expulsion chambers. The nozzles, the expulsion chambers, the heater elements and the associated electrical conductors are constructed in a plurality of metal layers and insulating layers supported by a silicon plate. The plate is fixed to the structure of the head and is supplied with ink contained in a movable cartridge fitted to the structure of the head. The cartridge comprises a rigid reservoir containing a sponge saturated with ink which can be hydraulically connected to the head by means of a needle-type conduit mounted on the head and which perforates a rubber membrane of the cartridge.

Abstract: The apparatus for manufacturing ink jet glass tubes includes a vertical mandrel which receives the tubes one at a time from a feeder and rotates them relative to a pair of gas nozzles for their heating. The tube is heated in an axially limited intermediary zone so as to form an hour-glass shaped profile.The profile of the tube is scanned by a television camera which generates two signals indicative of the internal diameter. These are compared electronically with a stored indication of the desired diameter and the two nozzles are rotated into an inactive position when this diameter is reached. The tube is cut along a plane so as to make the profile of the nozzle coincident with a reference profile by a device including an optical device connected to a cutting wheel to permit comparison of the hour-glass profile of the element with the reference profile. The severed end of the tube is then lapped and covered with a non-wettable material.

Abstract: The head comprises a hollow body (21) carrying a series of capillary tubes (12) of rigid material, on to each of which is fixed a sleeve-type piezoelectric transducer (16). A resin (26) is injected into the hollow body so as to encase first portions of the transducers. A flexible printed circuit (28) is connected to another portion (26) of the transducers, the circuit having a series of pairs of conducting areas hot-soldered to two conducting terminals disposed on the outside surfaces of the transducers.The printed circuit (28) is fixed between the hollow body (21) and an intermediate block (35) which is closed by means of a sealing diaphragm (38), having a series of sleeves (40) which are a close fit on the ends of the capillary tubes remote from the nozzles.