Abstract: An object of the present invention is to provide a stacked piezoelectric element with excellent durability, which exhibits an excellent piezoelectric performance irrespective of containing or not containing Pb in the ceramic layer, ensures sufficiently suppressed segregation of the electrically conducting base metal material in the ceramic layer and allows for no segregation of a strengthening substance itself.

Abstract: This invention provides a method for producing a stacked ceramic body that does not require strict control of an oxygen partial pressure in a sintering gas. To produce a stacked ceramic body by alternately stacking dielectric layer and electrode layers, an unsintered stacked body 2 is prepared by alternately stacking unsintered dielectric layers containing a PZT type dielectric material and unsintered electrode layers containing an electrode material, and is sintered in a sintering gas to which a dielectric layer anti-reducing agent 21 and an electrode layer anti-oxidant 22 are introduced. Alternatively, sintering is conducted in a gas containing only the dielectric layer anti-reducing agent 21 or in a gas containing only the electrode layer anti-oxidant 22.

Abstract: A laminate type dielectric device is formed by alternately laminating dielectric ceramic layers and electrode layers and integrally baking the laminate product. The electode layers are mainly made of an electrically conductive base metal material having greater standard Gibbs free energy for the formation of a metal oxide at a baking temperature than that of the ceramic material constituting the dielectric ceramic layers. Segregation of the materials including the electrically conductive base metal material does not occur at portions sandwiched between adjacent positive and negative electrode layers among the dielectric ceramic layers.

Abstract: A rotational member and a stationary member included in a spindle motor provided with air bearings are electrically connected while the bearing is rotating, and abrasion of the rotational member and the stationary member at stages of starting and stopping and damaging the rotational member and the stationary member by external shocks that may be exerted thereon during transportation and handling are avoided. In one embodiment, a sleeve is formed integrally with a motor base. The sleeve has an inside surface serving as a radial-bearing surface that forms a radial bearing together with the outside surface of a rotational shaft, and a thrust-bearing surface that forms thrust bearing together with a thrust plate attached to the rotational shaft. The radial-bearing surface of the sleeve is provided with a recess (groove) for holding lubricating oil while the rotational shaft is rotating.

Abstract: A PZT dielectric ceramic material is sintered at a desired low temperature to prevent deterioration of the performance of the base material. An auxiliary oxide is used that is made by adding the oxide of at least one of tungsten and molybdenum to lead oxide in the following proportions: PbOx+(WO3y+MoO3z) where x+y+z=1, 0.005<y+z<0.4 and y, z?0. 0.5 mol % to 20 mol % of this auxiliary oxide is added to a mixture of a stock material of dielectric ceramic material or its calcination having a composition of ABO3 type dielectric ceramic material where 0.9 molar ratio or more lead is included in site A assuming the proportion of site B is 1, and the material is mixed, formed and sintered. The content of tungsten and molybdenum combined is less than 0.098 mole in proportion to 1 mole of lead and the density of the dielectric ceramic material after sintering is 7.5 g/cm3 larger.

Abstract: The head position is corrected without relying on a servo signal that is positioning information. A readout signal amplitude 122 of a data portion is monitored and, if the readout signal amplitude of the data portion decreases, a read head 101 is compulsorily shifted by a minute width in a direction in which the readout signal amplitude increases, in order to compensate for the positioning error of the read head.

Abstract: A method of manufacturing large-sized laminated dielectrics of high quality which permit adjustment of the atmosphere during sintering process to be accomplished easily, and which can eliminate the problems such as expansion due to reaction with the atmosphere gas. When a laminated body 1, consisting of oxide dielectric layers 2 and inner electrode layers 3 having a base metal such as Cu as a main component, is sintered in a reducing atmosphere, a mixed gas having CO2 gas as a main component and containing optional amount of CO gas and O2 gas is used. By using the equilibrium system of CO2⇄2CO+(1/2)O2 and adjusting the amounts of CO gas and O2 gas, oxygen partial pressure in the atmosphere gas can be easily and stably adjusted and fluctuation and variation in the atmosphere can be suppressed.

Abstract: A laminated dielectric element of high quality, free of delamination and a method of producing the same. A method of producing a laminated dielectric element 1 by alternately laminating dielectric ceramic layers 12 and base metal electrode layers 13, comprising the steps of printing electrodes by applying a paste material for the base metal electrodes onto the surfaces of at least one side of the ceramic green sheets, laminating and press-adhering the ceramic green sheets to fabricate a laminate thereof, dewaxing the laminate, reducing the electrodes to form base metal electrode layers by heating the laminate while flowing an atmospheric gas and by reducing the paste material for the base metal electrodes, and sintering the laminate.

Abstract: An integrally fired, laminated electromechanical transducing element, fabricated using an inexpensive electrode material and having the electrode characteristic at least equivalent to that of the Ag—Pd electrode, is disclosed. Especially, in the integrally fired, laminated electromechanical transducing element according to the invention, (A) the rigidity of the internal electrode layers is low and the internal stress generated at the time of expansion or contraction of the ceramic layers is small, (B) the antimigration characteristic is superior, (C) the charge loss is small, the heat conductivity is high and the heat radiation characteristic is superior, and/or (D) the bonding strength between the ceramic layers and the electrode layers is high.

Abstract: This invention relates to a laminate type dielectric device capable of sufficiently bonding an electrode material such as Cu to a ceramic material by using an economical base metal material such as Cu, and fully exploiting the characteristics of a dielectric ceramic layer, a production method thereof, and an electrode paste material.

Abstract: A laminate type dielectric device is formed by alternately laminating dielectric ceramic layers and electrode layers and integrally baking the laminate product. The electrode layers are mainly made of an electrically conductive base metal material having greater standard Gibbs free energy for the formation of a metal oxide at a baking temperature than that of the ceramic material constituting the dielectric ceramic layers. Segregation of the materials including the electrically conductive base metal material does not occur at portions sandwiched between adjacent positive and negative electrode layers among the dielectric ceramic layers.

Abstract: A piezoelectric material exhibiting a high Curie point and a high displacement at a low drive voltage is provided. The piezoelectric material contains as a main component a composite oxide and is expressed by the general formula [Pb{1−x1−x2−&agr;(x1−x2)}, A1x1, A2x2] {(Tiy, Zrz) (1−&bgr;(x1−x2)−&ggr;), (Y0.5, Nb0.5)&ggr;}O3, where y+z=1, 1.15<z/y<1.30 and 0<&ggr;<0.1; and A1, A2, x1, x2 satisfy any of the conditions (i) A1 is at least selected one of Ce and La, A2 is K, 0.02≦x1<0.08, 0≦x2≦0.05 (0.02≦x1+x2≦0.1, x1≦x2) and &agr;=0, &bgr;=0.25 or &agr;=0.5, &bgr;=0, and (ii) A1 is Sr, A2 is Ba, 0.03≦x1≦0.05, 0.03≦x2≦0.05 (|x1−x2|≦0.01), and &agr;=0, &bgr;=0.

Abstract: This invention provides a method for producing a stacked ceramic body that does not require strict control of an oxygen partial pressure in a sintering gas. To produce a stacked ceramic body by alternately stacking dielectric layer and electrode layers, an unsintered stacked body 2 is prepared by alternately stacking unsintered dielectric layers containing a PZT type dielectric material and unsintered electrode layers containing an electrode material, and is sintered in a sintering gas to which a dielectric layer anti-reducing agent 21 and an electrode layer anti-oxidant 22 are introduced. Alternatively, sintering is conducted in a gas containing only the dielectric layer anti-reducing agent 21 or in a gas containing only the electrode layer anti-oxidant 22.

Abstract: To restrain temperature rise by controlling heat radiation from an IC. More specifically, an area of junctioning pads which are in contact with an IC is enlarged to substantially overlap the whole or at least half or more of the area of the IC. Further, the IC is covered with an overcoat which protrudes to other parts of a head supporting mechanism.

Abstract: It is an object of the present invention to manufacture large-sized laminated dielectrics of high quality which permit adjustment of the atmosphere during sintering process to be accomplished easily, and which can eliminate the problems such as expansion due to reaction with the atmosphere gas.

Abstract: An object of the present invention is to make it possible to sinter a PZT dielectric ceramic material at a desired low temperature and to prevent deterioration of the performance of the base material.

Abstract: An integrally fired, laminated electromechanical transducing element, fabricated using an inexpensive electrode material and having the electrode characteristic at least equivalent to that of the Ag—Pd electrode, is disclosed. Especially, in the integrally fired, laminated electromechanical transducing element according to the invention, (A) the rigidity of the internal electrode layers is low and the internal stress generated at the time of expansion or contraction of the ceramic layers is small, (B) the antimigration characteristic is superior, (C) the charge loss is small, the heat conductivity is high and the heat radiation characteristic is superior, and/or (D) the bonding strength between the ceramic layers and the electrode layers is high.

Abstract: A piezoelectric element having a structure capable of suppressing deformation during the fabrication thereof is disclosed. The piezoelectric element comprises a drive portion 101 including a plurality of ceramic layers 11 of a piezoelectric ceramic, a plurality of internal electrode layers 2 formed of a base metal as a main component for supplying electricity to the ceramic layers 11, and a dummy portion 103 formed at least on one end surface of the ceramic layers 11 of the drive portion 101 along the direction of stacking thereof, the ceramic layers 11 and the internal electrode layers 2 being stacked alternately. The dummy portion 103 is composed of ceramic and has at least one dummy electrode layer 3 of the same material as the internal electrode layers 2.

Abstract: This invention relates to a laminate type dielectric device capable of sufficiently bonding an electrode material such as Cu to a ceramic material by using an economical base metal material such as Cu, and fully exploiting the characteristics of a dielectric ceramic layer, a production method thereof, and an electrode paste material.

Abstract: This invention provides a method of producing a laminate type dielectric device free from peeling of an electrode layer and a ceramic layer and from voids in both electrode layer and ceramic layer, and an electrode paste material. The invention relates also to an electrode paste material for constituting electrode layers of a laminate type dielectric device produced by at least the steps of alternately laminating ceramic layers 11 containing a lead element as a constituent component and electrode layers 2, and degreasing and baking the laminate, wherein the electrode paste material contains CuO as a principal component of a starting material of an electrically conductive material, a solvent, a binder, and a cooperative material consisting of at least one kind of the main components constituting the ceramic layer 11.