Abstract: An electroacoustic transducer has a housing, piezoelectric speaker, dynamic speaker, and support member. The piezoelectric speaker includes a vibration plate having a first surface and a second surface on the opposite side of the first surface, as well as a piezoelectric element joined to at least one of the first surface and second surface, and divides the interior of the housing into a first space facing the first surface and a second space facing the second surface. The dynamic speaker is placed in the first space. The support member is constituted by a part of the housing or by a member different from the housing, has a supporting part facing the first surface or second surface, and supports the periphery of the first surface or second surface with the supporting part.

Abstract: A dielectric porcelain composition with a sintering density of 93% or above, is expressed by the composition formula below: 100[1?x(0.94Bi1/2Na1/2TiO3?0.06BaTiO3)?xK0.5Na0.5NbO3]+?CuO+?LiF (wherein x is between 0.14 and 0.28, and ? and ? meet either (I) ? is between 0.4 and 1.5, and ? is between 0 and 2.4, or (II) ? is between 0 and 1.5, and ? is between 0.2 and 2.4). The dielectric porcelain composition is Pb-free and can be sintered at low temperature, as well as a dielectric element having such composition.

Abstract: A piezoelectric ceramic composition contains a perovskite composition which is represented by (Pba·Rex){Zrb·Tic, ·(Ni1/3Nb2/3)d·(Zn1/3Nb2/3)e}O3 (wherein Re represents La and/or Nd, and a-e and x satisfy the following conditions 0.95?a?1.05, 0?x?0.05, 0.35?b?0.45, 0.35?c?0.45, 0<d?0.10, 0.07?e?0.20 and b+c+d+e=1) and 0.05-0.3% by mass of an Ag component in terms of oxides relative to the perovskite composition.

Abstract: In an embodiment, an electroacoustic transducer has a piezoelectric speaker 20, housing, and support member 23. The piezoelectric speaker 20 has a vibration plate 11 with a periphery 111, and a piezoelectric element 12 joined to the vibration plate 11. The housing houses the piezoelectric speaker 20. The support member 23 is constituted by a part of the housing or by a separate member, and supports the vibration plate 11 in multiple areas along the periphery 111. The electroacoustic transducer can offer excellent high-frequency characteristics.

Abstract: In a piezoelectric ceramic which has an alkali-containing niobate-based perovskite structure in which constituent elements are Li, Na, K, Nb, and O, a Li3NbO4 crystal phase is intentionally deposited on a piezoelectric ceramic having an alkali-containing niobate-based perovskite structure, whereby sintering becomes possible at about 1000° C. rather than at the normally required sintering temperature of 1050° C. or greater.

Abstract: A dielectric porcelain composition with a sintering density of 93% or above, is expressed by the composition formula below: 100[1?x(0.94Bi1/2Na1/2TiO3?0.06BaTiO3)?xK0.5Na0.5NbO3]+?CuO+?LiF (wherein x is between 0.14 and 0.28, and ? and ? meet either (I) ? is between 0.4 and 1.5, and ? is between 0 and 2.4, or (II) ? is between 0 and 1.5, and ? is between 0.2 and 2.4). The dielectric porcelain composition is Pb-free and can be sintered at low temperature, as well as a dielectric element having such composition.

Abstract: A piezoelectric device has a piezoelectric ceramic layer obtained by sintering a piezoelectric ceramic composition that contains an alkali-containing niobate type perovskite composition which is represented by (Li1NamK1-1-m)n(Nb1-oTao)O3 (wherein 0.04?1?0.1, 0?m<1, 0.95?n?1.05, 0?o?1) and Ag component, as well as a conductor layer sandwiching the piezoelectric ceramic layer. The piezoelectric ceramic layer has Ag segregated in voids present in a sintered compact of the perovskite composition in terms of oxides relative to the perovskite composition.

Abstract: A piezoelectric ceramic is constituted by a polycrystal whose main phase is an alkali-containing niobate perovskite structure, where both elemental nickel and elemental manganese are present at the grain boundary of the polycrystal. The piezoelectric ceramic is such that drop in piezoelectric characteristics due to application of high electric field is suppressed.

Abstract: A piezoelectric device is provided with: a piezoelectric ceramic layer that is obtained by firing a piezoelectric ceramic composition which contains a perovskite composition and an Ag component; and a conductor layer that sandwiches the piezoelectric ceramic layer, wherein Ag is segregated in voids in a sintered body of the perovskite composition in the piezoelectric ceramic layer. The piezoelectric ceramic composition preferably contains a perovskite composition which is represented by (Pba.Rex){Zrb.Tic,.(Ni1/3Nb2/3)d.(Zn1/3Nb2/3)e}O3 (wherein Re represents La and/or Nd, and a-e and x satisfy the following conditions 0.95?a?1.05, 0?x?0.05, 0.35?b<0.45, 0.35?c?0.45, 0?d?0.10, 0.07?e?0.20 and b+c+d+e=1) and 0.05-0.3% by mass of an Ag component in terms of oxides relative to the perovskite composition.

Abstract: A piezoelectric speaker has a piezoelectric element and vibration plate. The piezoelectric element has a base body with a mounting surface, as well as first and second terminals that are formed on the mounting surface with a distance between them. The vibration plate has a conductive body joined to the piezoelectric element and having a principle surface facing the mounting surface, as well as a first hole with or without a bottom which is formed on the principle surface in a region facing the first terminal to form a space between the body and first terminal. The piezoelectric speaker is capable of preventing the external electrodes of the piezoelectric element from shorting to each other.

Abstract: An electroacoustic transducer has a housing, piezoelectric speaker, dynamic speaker, and support member. The piezoelectric speaker includes a vibration plate having a first surface and a second surface on the opposite side of the first surface, as well as a piezoelectric element joined to at least one of the first surface and second surface, and divides the interior of the housing into a first space facing the first surface and a second space facing the second surface. The dynamic speaker is placed in the first space. The support member is constituted by a part of the housing or by a member different from the housing, has a supporting part facing the first surface or second surface, and supports the periphery of the first surface or second surface with the supporting part.

Abstract: In an embodiment, an electroacoustic transducer has a piezoelectric speaker 20, housing, support member 73, and elastically deformable adhesive layer 74. The piezoelectric speaker 20 has a vibration plate 11 with a periphery 111, and a piezoelectric element 12 joined to the vibration plate 11. The housing houses the piezoelectric speaker 20. The support member 73 is constituted by a part of the housing or by a separate member, and supports the periphery 111. The adhesive layer 74 is provided between the periphery 111 and support member 73. The electroacoustic transducer can offer excellent high-frequency characteristics.

Abstract: In an embodiment, an electroacoustic transducer has a piezoelectric speaker 20, housing, and support member 23. The piezoelectric speaker 20 has a vibration plate 11 with a periphery 111, and a piezoelectric element 12 joined to the vibration plate 11. The housing houses the piezoelectric speaker 20. The support member 23 is constituted by a part of the housing or by a separate member, and supports the vibration plate 11 in multiple areas along the periphery 111. The electroacoustic transducer can offer excellent high-frequency characteristics.

Abstract: In an embodiment, an electroacoustic converter (earphone 100) has an enclosure 41, piezoelectric sounding body 32, electromagnetic sounding body 31, and passage 35. The piezoelectric sounding body 32 includes a vibration plate 321 having a periphery supported directly or indirectly on the enclosure 41, and a piezoelectric element 322 placed at least on one side of the vibration plate 321. The piezoelectric sounding body 32 divides the interior of the enclosure 41 into a first space S1 and a second space S2. The electromagnetic sounding body 31 is placed in the first space S1. A passage 35 is provided in or around the piezoelectric sounding body 32, to connect the first space S1 and second space S2. The electroacoustic converter is capable of obtaining desired frequency characteristics easily.

Abstract: In an embodiment, an electroacoustic converter (earphone 100) has an enclosure 41, piezoelectric sounding body 32, electromagnetic sounding body 31, and passage 35. The piezoelectric sounding body 32 includes a first vibration plate 321 having a periphery supported directly or indirectly on the enclosure 41, and a piezoelectric element 322 placed at least on one side of the vibration plate 321. The piezoelectric sounding body 32 has a second vibration plate and divides the interior of the enclosure 41 into a first space S1 and a second space S2. The electromagnetic sounding body 31 is placed in the first space S1. The passage 35 is provided in or around the piezoelectric sounding body 32 to connect the first space S1 and second space S2. The electroacoustic converter is capable of obtaining desired frequency characteristics easily.

Abstract: In an embodiment, an electroacoustic converter has an enclosure, piezoelectric sounding body, electromagnetic sounding body, passage, and wiring members. The piezoelectric sounding body includes a first vibration plate supported directly or indirectly on the enclosure, and a piezoelectric element placed at least on one side of the first vibration plate. The piezoelectric sounding body divides the interior of the enclosure into a first space and a second space. The electromagnetic sounding body has a second vibration plate and is placed in the first space. The passage is provided at the piezoelectric sounding body or around the piezoelectric sounding body, to connect the first space and second space. The wiring members are electrically connected to the piezoelectric element and led out toward the electromagnetic sounding body, from the piezoelectric element, through the first space or second space.

Abstract: A piezoelectric ceramic composition contains a perovskite composition which is represented by (Pba.Rex){Zrb.Tic, .(Ni1/3Nb2/3)d.(Zn1/3Nb2/3)e}O3 (wherein Re represents La and/or Nd, and a-e and x satisfy the following conditions 0.95?a?1.05, 0?x?0.05, 0.35?b?0.45, 0.35?c?0.45, 0<d?0.10, 0.07?e?0.20 and b+c+d+e=1) and 0.05-0.3% by mass of an Ag component in terms of oxides relative to the perovskite composition.

Abstract: A piezoelectric element includes first internal electrodes and second electrodes, as well as piezoelectric ceramic layers that are made of ceramics and arranged between the first internal electrodes and second internal electrodes. Manganese is present relatively more abundantly in the areas of the piezoelectric ceramic layers adjacent to the first internal electrodes and second internal electrodes, compared to at the centers of the piezoelectric ceramic layers. Insulation performance of the piezoelectric element is kept from dropping over the course of use.

Abstract: A piezoelectrically actuated element includes a composite ceramic to which an alternating electric field is applied through external electrodes that are orthogonal to the polarization direction, wherein the composite ceramic is formed from a first piezoelectric ceramic having soft spring characteristics such that the elastic constant decreases with increasing vibration velocity, and a second piezoelectric ceramic having hard spring characteristics such that the elastic constant increases with increasing vibration velocity. Even when the applied electric field is intensified to increase the vibration velocity of the piezoelectrically actuated element, the overall change in the elastic constant is minimized, and fluctuations in the resonance frequency is suppressed.

Abstract: A stacked piezoelectric actuator has a laminate structure including piezoelectric layers and cover parts such that when an external electrode is applied with drive voltage, the piezoelectric layers become distorted and the entire stacked piezoelectric actuator deforms, and at that time, the cover parts become displaced, wherein the distortion difference occurring between the piezoelectric layers and the cover parts reduces, thereby inhibiting the development of cracks. Moreover, the surface area of the active region of the piezoelectric layers is the same as the surface area of the active region of the cover parts, and therefore the loss of the displacement transfer, which is produced by the piezoelectric layers, at the cover parts is reliably reduced.