Abstract: Disclosed herein is an ink jet printer head including a substrate which includes a piezoelectric member polarized across a thickness thereof and a plate-like low-rigid member bonded to an upper surface of the piezoelectric member. The low-rigid member has a low permittivity and a rigidity lower than that of the piezoelectric member. The substrate has a plurality of grooves cut from an upper surface of the low-rigid member to a depth beyond a bonded surface between the low-rigid member and the piezoelectric member. A top plate is bonded to the upper surface of the low-rigid member so as to cover upper openings of the grooves, thereby defining a plurality of pressure chambers between the grooves and the top plate. A plurality of ink jet nozzles are provided so as to respectively communicate with the pressure chambers. A plurality of electrodes are formed on inner surfaces of the pressure chambers.

Abstract: An ink jet print head includes pressure chambers divided by side walls formed at least partially of a piezoelectric member, voltage is applied to electrodes formed on surface of side walls, and jets ink in the pressure chambers through ink jets by causing deformation of shearing strain mode to the side walls. Each one of the side walls disposed on both sides of the pressure chambers has different operating characteristics. The volume of the ink to be jetted can be changed in three ways by selectively deforming either of the side walls of the pressure chamber from which the ink is to be jetted or by deforming both of the side walls of the pressure chamber simultaneously. Accordingly, gradation can be acquired by a simply constructed print head.

Abstract: A method of fabricating an ink jet print head which jets ink through an ink jet nozzle by pressurizing the ink supplied to a pressure chamber from an ink supplying portion, including applying flowable resin on a surface of a piezoelectric member polarized along a thickness thereof; forming a low rigidity member having a rigidity less than that of the piezoelectric member by curing the resin; grinding a surface of the low rigidity member; forming a plurality of grooves extending from the surface of the low rigidity member to an inside of the piezoelectric member; forming electrodes on the entire inner surface of the grooves; and sticking a top plate on the ground surface to close an opening of the grooves, thereby forming a plurality of pressure chambers communicating with an ink supplying portion and the ink jet nozzle. Since the low rigidity member is cured before it is ground, the proportion of the height of the low rigidity member and the piezoelectric member is equalized.

Abstract: An ink jet print head comprises a piezoelectric plate (2) formed of a piezoelectric material, a base plate (1) formed of a nonconductive, nonelectrostrictive material having rigidity lower than that of the piezoelectric material and joined to the piezoelectric plate (2), electrodes (8) formed by depositing a metal by electroless plating over the entire bottom surfaces of a plurality of parallel grooves (3) formed through the piezoelectric plate (2) into the base plate (1) and the entire side surfaces of side walls (4) each consisting of an upper side wall (4a) formed in the piezoelectric plate (2) and lower side wall (4b) formed in the base plate (2) between the grooves (3), a top plate (10) joined to the upper surface of the piezoelectric plate (2) so as to close the upper open ends of the grooves (3) to form pressure chambers (14), and a nozzle plate (12) provided with ink jets (11) and joined to one end of the assembly of the base plate (1), the piezoelectric plate (2) and the top plate (10) so that the in

Abstract: An adhesive layer 15 is formed over one major surface of a flat base plate 1 having a relatively high rigidity, a piezoelectric plate 2 is joined to the adhesive layer 15, a plurality of parallel grooves 3 are formed through the piezoelectric plate 2 into the adhesive layer 15, a metal is deposited over the surfaces of the grooves 3 to form electrodes 8, a top plate 10 is attached to the upper surface of the piezoelectric plate 2 so as to close the upper open ends of the grooves 3, and a nozzle plate 12 provided with a plurality of ink jets is attached to one end of the assembly of the base plate 1, the adhesive layer 15, the piezoelectric plate 2 and the top plate 10 so as to close the open longitudinal ends of the grooves 3 to form a plurality of pressure chambers 14.

Abstract: A method of manufacturing a print head for an ink-jet printer comprises steps of: forming a main plate (1) by superposing a first piezoelectric plate (2), a first low-rigidity plate (5), a second low-rigidity plate (6) and a second piezoelectric plate (3) in that order in a laminated structure; cutting a plurality of parallel first and second grooves (7, 9) through the first piezoelectric plate into the first low-rigidity plate and through the second piezoelectric plate into the second low-rigidity plate, respectively, by grinding to form first and second walls (8, 10); forming first and second electrodes (14, 15) respectively over the side surfaces of the first and second walls (8, 10); attaching a top plate (17) and a bottom plate (18) respectively to the outer surfaces of the first and second piezoelectric plates (2, 3) to form first and second pressure chambers (22, 23) respectively in the opposite sides of the main plate (1); and attaching an orifice plate (20) provided with a plurality of ink jets ( 19)

Abstract: An adhesive layer 15 is formed over one major surface of a flat base plate 1 having a relatively high rigidity, a piezoelectric plate 2 is joined to the adhesive layer 15, a plurality of parallel grooves 3 are formed through the piezoelectric plate 2 into the adhesive layer 15, a metal is deposited over the surfaces of the grooves 3 to form electrodes 8, a top plate 10 is attached to the upper surface of the piezoelectric plate 2 so as to close the upper open ends of the grooves 3, and a nozzle plate 12 provided with a plurality of ink jets is attached to one end of the assembly of the base plate 1, the adhesive layer 15, the piezoelectric plate 2 and the top plate 10 so as to close the open longitudinal ends of the grooves 3 to form a plurality of pressure chambers 14.

Abstract: An ink jet print head comprises a piezoelectric plate (2) formed of a piezoelectric material, a base plate (1) formed of a nonconductive, nonelectrostrictive material having rigidity lower than that of the piezoelectric material and joined to the piezoelectric plate (2), electrodes (8) formed by depositing a metal by electroless plating over the entire bottom surfaces of a plurality of parallel grooves (3) formed through the piezoelectric plate (2) into the base plate (1) and the entire side surfaces of side walls (4) each consisting of an upper side wall (4a) formed in the piezoelectric plate (2) and lower side wall (4b) formed in the base plate (2) between the grooves (3), a top plate (10) joined to the upper surface of the piezoelectric plate (2) so as to close the upper open ends of the grooves (3) to form pressure chambers (14), and a nozzle plate (12) provided with ink jets (11) and joined to one end of the assembly of the base plate (1), the piezoelectric plate (2) and the top plate (10) so that the in

Abstract: A method of producing a printer head wherein a substrate including at least one piezoelectric member polarized in its thickness direction is formed. A plurality of grooves and a plurality of posts are alternately defined in the substrate. A pre-processing solution is allowed to flow along the grooves at the following relative velocity so as to effect pre-processing when the velocity of the pre-processing solution for electroless plating relative to an object to be plated is V, the height of each of electrodes formed on the internal surfaces of the grooves is H, the width of each groove is W and a contact angle at which the pre-processing solution is brought into contact with the internal surfaces of the grooves is .theta..VW.sup.2 (1+cos.theta. )/H.sup.2 >0.6 mm/sThereafter, the substrate is immersed in an electroless plating solution to form the electrodes.

Abstract: A piezoelectric plate polarized in the direction of its thickness and a base plate having a rigidity lower than that of the piezoelectric plate are joined together. A plurality of parallel grooves are cut through the piezoelectric plate into the base plate so that the grooves are separated from each other by side walls each having an upper portion formed of the piezoelectric plate and a lower portion formed of the base plate. A top plate is attached to the upper surface of the piezoelectric plate to close the upper open ends of the grooves. A nozzle plate provided with a plurality of ink jets is attached to one end of the assembly of the base plate, the piezoelectric plate and the top plate so that the ink jets correspond respectively to the grooves to form pressure chambers. Electrodes are formed by depositing a metal over bottom surface of the grooves and side surfaces of the side walls.

Abstract: A method of producing an ink-jet type printer head wherein a plurality of plate-shaped piezoelectric members are stuck onto the surface of a low-rigidity member so that they are disposed adjacent to the low-rigidity member. A plurality of grooves extending from the surfaces of the piezoelectric members to the inside of the low-rigidity member are defined by grinding in parallel at given intervals inclusive of positions at which the grooves extend through joints between the adjacent piezoelectric members. In addition, posts are formed on both sides of each of the grooves and electrodes are disposed on both inner sides of each groove. A roof is stuck on the surfaces of the piezoelectric members so as to define a plurality of pressure chambers having one end in which a plurality of nozzles are formed.

Abstract: Supporting parts are disposed on both sides of the end parts of a plurality of armatures to which needles are fixed. Elastic members are held by elastic-member-holding parts with limited play in the longitudinal direction of the armatures. The elastic members are inserted into wide holding parts allowing play in the longitudinal direction of the armatures, and needles are disposed in fixed positions. The elastic members are welded to elastic-member-holding parts and wide holding parts with the tip positions of needles used as standards.

Abstract: A dot print head comprising a yoke, a plurality of cores formed integrally with the yoke in an annular arrangement in the peripheral portion of the yoke, solenoid coils wound respectively around the cores, armatures fixedly provided respectively with styluses, an armature support supporting each armature at the middle portion thereof opposite to the corresponding core for swing motion, and an armature holding member disposed opposite to the yoke with a predetermined gap therebetween to hold the armatures on the armature support for swing motion. A plurality of joining parts are formed on the yoke on a line on which the cores are arranged, and a plurality of joining parts are formed on the armature holding member so as to be joined respectively to the connecting parts of the yoke in joining together the yoke and the armature holding member.

Abstract: A release-type dot print head formed by joining together a magnet unit, and an armature unit formed by brazing torsion bars to armatures and supporting parts formed integrally with a second yoke with the armatures in a state in which the free ends of styluses fixed to the free ends of the armatures project from the outer surface of a stylus guide attached to the second yoke by a predetermined length. Portions of the free ends of the styluses projecting from the outer surface of the stylus guide are cut off by a wire-cut electrical discharge cutting process with the styluses in a free state to adjust the length of projection of the free ends of the stylus to a predetermined length. The second yoke and the stylus guide are formed respectively of materials having substantially the same coefficients of thermal expansion. The armature unit is subjected to heat treatment after assembly.

Abstract: A release type dot print head employing cores formed of a difficult-to-machine magnetic alloy containing iron and cobalt as the principal components and having a high saturation magnetic flux density. The cores are fabricated easily by processing plates of the magnetic alloy in a simple shape and are combined respectively with auxiliary cores formed of an easily workable material. Thus, the principal components of the release type dot print head can be easily fabricated and assembled.

Abstract: A dot print head including armatures, supporting parts for supporting the armatures, and torsion bars for supporting the armatures on the supporting parts. Open grooves are formed at least in either the armatures or the supporting parts to place the torsion bars therein, to contain a brazing filler metal therein and to braze the torsion bars to the armatures or the supporting parts by melting the brazing filler metal in the open grooves, and flanges are formed integrally with each torsion bar so as to be positioned between the elastic portions of the torsion bar and the open grooves. The width of the base end of each armature or that of each supporting part is reduced to form a gap between the armature and the supporting part in a width sufficient to form the elastic portion of the torsion bar in a length greater than a predetermined value.

Abstract: A dot printer head in which each radially directed armature is urged to pivot about its primary fulcrum in the return direction by a metallic return spring and is urged to pivot in the opposite angular direction by a metallic holding spring. The metallic return springs and metallic holding springs are sized and positioned so that the metallic holding springs exert a torque urging the radially directed armature to pivot in the actuating direction that is lower than the torque urging the armatures to pivot in the return direction.

Abstract: The printhead is constructed such that opposed surfaces of armatures are formed between the armatures adjacent to each other with small gap being left therebetween and cores opposed to each of the armatures are provided with alternative opposed magnetic fluxes. The armatures are supported in such a way that the guide holes formed in the middle of each armature are engaged with the fixed armature guides without interfering with their side surfaces, and thereby side magnetic paths of sufficient cross sectional area can be formed, and further their equivalent mass can be decreased and a high speed printing is enabled, and the armatures can be moved smoothly.

Abstract: A dot printer head in which a radial array of armatures are disposed opposite to a yoke and cores equipped with coils, and the armatures are actuated together with needles by exciting the coils to perform a desired printing operation. In this arrangement, a magnetic flux generated from each core flows to the yoke via the associated armature and then returns to the former core while partially flowing through another magnetic path by way of the adjacent armature to the yoke and returning to the former core, whereby required magnetic paths are obtained without the necessity of increasing the areas of the mutually opposed surfaces of the armature and the yoke. Thus, the radial width of the yoke is reduced as well as the distance from the fulcrum of the armature to the core, so that the distance from the fulcrum of the armature to the fore end thereof can be sufficiently lengthened against the distance from the armature fulcrum to the core.

Abstract: The present invention provides a release type dot printer head wherein an urging force of an armature in a printing direction for driving a print needle is exerted by a non-linear spring such as a conical spring. Hence, the urging force can correspond to a variation of an attracting force of the armature by a permanent magnet. Consequently, an energizing current for a coil can be reduced, and thus high speed printing can be attained by the arrangement.