Abstract: Odd-numbered piezoelectric sheets 22, 21b, 21d, and 21f are formed with a plurality of individual electrodes 24. Even-numbered piezoelectric sheets 21a, 21c, 21e, and 21g are formed with a common electrode 25. These odd-numbered and even-numbered piezoelectric sheets are alternatively arranged one on the other to form a laminated body. A top sheet 23 is mounted on the laminated body. Surface electrodes 30, 31 are formed on the top sheet 23. Through holes 32, 33 are opened to the piezoelectric sheets 21a through 21g for providing electrical connection of the individual electrodes 24 and the common electrodes 25, but not to the piezoelectric sheet 22 that is laminated on a cavity plate 10.

Abstract: A print head for a piezoelectric ink jet printer includes a piezoelectric actuator in the form of a plate, which lies on one side of a metallic cavity plate. The actuator includes drive electrodes and side electrodes. The side electrodes are formed on a side face of the actuator and each connected with one of the drive electrodes. The cavity plate has pressure chambers each aligned with one of the drive electrodes. The cavity plate also has nozzles each communicating with one of the chambers. The cavity plate further has a recess formed on the one side. The side electrodes are aligned with the recess to be kept out of contact with the cavity plate. Another print head for a piezoelectric ink jet printer includes a piezoelectric actuator in the form of a plate, which lies on a cavity plate. The actuator has recesses formed in a side face of it, and includes drive electrodes and side electrodes. Each side electrode is formed in one of the recesses and connected with one of the drive electrodes.

Abstract: A reliable piezoelectric actuator whose warpage is prevented and of which electrodes are prevented from peeling off, and an ink-jet print head including the piezoelectric actuator are manufactured. A piezoelectric sheet having individual electrodes formed thereon and another piezoelectric sheet having common electrodes formed thereon are stacked alternately on top of each other in layers, with an insulating sheet having surface electrodes placed on the top. Each piezoelectric sheet has through holes. The through holes are formed such that through holes adjacent in a direction parallel to the alignment of the individual electrodes are not aligned.

Abstract: An actuator for the print head of an ink jet printer is fitted to the ink channels of the head. The actuator includes an active layer and a restraining layer. One side of the active layer faces the ink channels. The active layer can deform with a drive voltage applied to it. The restraining layer is provided on the other side of the active layer, and cannot be activated with a drive voltage. The restraining layer restrains the active layer from deforming. It is possible to integrally form the active and restraining layers by stacking green sheets and calcining the stacked sheets at the same time. This makes it possible to provide an actuator simple in structure and low-cost.

Abstract: A plate-shaped piezoelectric actuator 20 is formed from ten piezoelectric sheets 21 to 30 that are stacked in a laminated configuration. Drive electrodes 36 are formed on the upper surface of each piezoelectric sheet 26, 28, and 30 at positions that correspond to pressure chambers 16 provided on a cavity plate 10. A band-shaped common electrode 35 is formed on the surface of each of the piezoelectric sheets 23, 24, 25, 27, and 29. The piezoelectric sheets 25 to 30 are subjected to polarization processes by applying a voltage between the common electrodes 35 and corresponding ones of the drive electrodes 36 and between the drive electrode 36 of the lowermost piezoelectric sheet 30 and the cavity plate 10. Then, the common electrodes 35 provided on the piezoelectric sheets 25, 27, 29 and the cavity plate 10 are all connected to the ground 60. With this configuration, the piezoelectric sheet 30 as well as the piezoelectric sheets 26 to 29 function as active layers and deform by the piezoelectric effect.

Abstract: A reliable piezoelectric actuator whose warpage is prevented and of which electrodes are prevented from peeling off, and an ink-jet print head including the piezoelectric actuator are manufactured. A piezoelectric sheet having individual electrodes formed thereon and another piezoelectric sheet having common electrodes formed thereon are stacked alternately on top of each other in layers, with an insulating sheet having surface electrodes placed on the top. Each piezoelectric sheet has through holes. The through holes are formed such that through holes adjacent in a direction parallel to the alignment of the individual electrodes are not aligned.

Abstract: A plate-shaped piezoelectric actuator 20 is formed from ten piezoelectric sheets 21 to 30 that are stacked in a laminated configuration. Drive electrodes 36 are formed on the upper surface of each piezoelectric sheet 26, 28, and 30 at positions that correspond to pressure chambers 16 provided on a cavity plate 10. A band-shaped common electrode 35 is formed on the surface of each of the piezoelectric sheets 23, 24, 25, 27, and 29. The piezoelectric sheets 25 to 30 are subjected to polarization processes by applying a voltage between the common electrodes 35 and corresponding ones of the drive electrodes 36 and between the drive electrode 36 of the lowermost piezoelectric sheet 30 and the cavity plate 10. Then, the common electrodes 35 provided on the piezoelectric sheets 25, 27, 29 and the cavity plate 10 are all connected to the ground 60. With this configuration, the piezoelectric sheet 30 as well as the piezoelectric sheets 26 to 29 function as active layers and deform by the piezoelectric effect.

Abstract: An ink jet print head includes a cavity plate having a plurality of nozzles and a plurality of pressure chambers communicating with the respective nozzles, and a plate-like piezoelectric actuator, in which piezoelectric sheets having a plurality of electrodes formed at positions with respect to the pressure chambers are stacked one after another. The piezoelectric actuator is bonded to the cavity plate so as to close the pressure chambers in the cavity plate. Each of the piezoelectric sheets has a thickness of between 5-40 &mgr;m, preferably between 15-30 &mgr;m. Surface electrodes, which electrically connect one of the electrodes, are provided at both end portions of a surface of the piezoelectric actuator, which is opposed to a surface to be bonded to the cavity plate. Protrusions having a thickness of the surface electrodes are provided between the surface electrodes on the surface of the piezoelectric actuator.

Abstract: An ink impermeable and electrically insulative adhesive sheet is pasted to the lower surface of a piezoelectric actuator, which is constructed by laminating alternately a piezoelectric sheet with individual electrodes and a piezoelectric sheet with a common electrode. Then, the piezoelectric actuator is bonded to a cavity plate by the aid of the adhesive sheet such that the individual electrodes of the piezoelectric actuator are aligned with pressure chambers of the cavity plate. In this construction, electrical insulation between the piezoelectric sheets is not damaged by ink in the pressure chambers of the cavity plate.

Abstract: Odd-numbered piezoelectric sheets 22, 21b, 21d, and 21f are formed with a plurality of individual electrodes 24. Even-numbered piezoelectric sheets 21a, 21c, 21e, and 21g are formed with a common electrode 25. These odd-numbered and even-numbered piezoelectric sheets are alternatively arranged one on the other to form a laminated body. A top sheet 23 is mounted on the laminated body. Surface electrodes 30, 31 are formed on the top sheet 23. Through holes 30, 31 are opened to the piezoelectric sheets 21a through 21g for providing electrical connection of the individual electrodes 24 and the common electrodes 25, but not to the piezoelectric sheet 22 that is laminated on a cavity plate 10.

Abstract: A print head for a piezoelectric ink jet printer includes a piezoelectric actuator in the form of a plate, which lies on one side of a metallic cavity plate. The actuator includes drive electrodes and side electrodes. The side electrodes are formed on a side face of the actuator and each connected with one of the drive electrodes. The cavity plate has pressure chambers each aligned with one of the drive electrodes. The cavity plate also has nozzles each communicating with one of the chambers. The cavity plate further has a recess formed on the one side. The side electrodes are aligned with the recess to be kept out of contact with the cavity plate. Another print head for a piezoelectric ink jet printer includes a piezoelectric actuator in the form of a plate, which lies on a cavity plate. The actuator has recesses formed in a side face of it, and includes drive electrodes and side electrodes. Each side electrode is formed in one of the recesses and connected with one of the drive electrodes.

Abstract: An arrangement of two elements of a sewing machine which are in frictional, or sliding, contact during operation. At least one of elements is formed of a ceramic material and a minute amount of a lubrication oil is applied to the frictional, or siding, portion defining the surfaces in contact. Such a combination of elements is found in the upper looper mechanism, the shuttle body assembly, the needle bar mechanism and the fabric piece feeding mechanism in a sewing machine that are subject to high speed, high load friction or sliding conditions.