Kyocera Corporation

Masaki Terazono

Takeshi Okamura

Katsushi Sakaue

Shigenobu Nakamura

Ken Yamamoto

Mitsuo Kondo

Takafumi Tsurumaru

Tomohiro Kawamoto

Hideki Uchimura

Takaaki Hira

Masahiro Sato

Shoji Kohsaka

Satoru Kamitani

Masahito Nakanishi

Hirotaka Tsuyoshi

Yasushi Migita

Susumu Ono

Akira Saito

Shoji Kousaka

Kazumi Osamura

Kazunori Koga

Hitoshi Atari

Kouichi Tanaka

Masahiro Satoh

Naohito Higashi

Ichio Kiyofuji

Junji Ohe

Shoji Kosaka

Ryuusuke Tsuyoshi, Legal Representative

An acoustic generator according to one embodiment includes an exciter, a vibrating portion, a frame, and a lead. The exciter receives an input of an electrical signal and is caused to vibrate. The exciter is mounted on the vibrating portion, and the vibrating portion is caused to vibrate by the vibration of the exciter. The frame is provided on an external circumferential portion of the vibrating portion, and supports the vibrating portion substantially flat. The lead is connected to the exciter, and inputs an electrical signal to the exciter. The frame includes a terminal serving as a connection point to the lead.

Acoustic generator, acoustic generation device, and electronic device

An acoustic generator includes a vibrating body. The acoustic generator includes a frame member attached by a bonding material to an external peripheral portion of the vibrating body. The acoustic generator has an exciter provided on the vibrating body inside of the frame member. In this case, the acoustic generator further includes an extended portion of the bonding material provided to be extended on the vibrating body inside of the frame from the frame member.

Acoustic generator, acoustic generating device, and electronic device

An object is to flatten a frequency characteristic. For achieving the object, an acoustic generator according to an embodiment includes a piezoelectric element (exciter) and a film (film-like vibrating body). The piezoelectric element receives input of an electric signal and vibrates. The piezoelectric element is bonded to the film through a bonding material and the film vibrates together with the piezoelectric element with the vibration of the piezoelectric element. Furthermore, the acoustic generator in the embodiment has voids in the bonding material.

A multilayer piezoelectric element includes a plurality of piezoelectric layers and a plurality of metal layers stacked alternately. The plurality of metal layers include a plurality of low-filled metal layers having a lower filling rate of metal composing the metal layers than oppositely disposed metal layers adjacent to each other in a stacking direction. The plurality of metal layers may include a plurality of thin metal layers having a smaller thickness than oppositely disposed metal layers adjacent to each other in a stacking direction. Where the plurality of metal layers are composed mainly of an alloy, the plurality of metal layers may include a plurality of high-ratio metal layers having a higher ratio of a component constituting the alloy than oppositely disposed metal layers adjacent to each other in a stacking direction.

Multilayer piezoelectric element and injector using the same

In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately, the plurality of metal layers include a plurality of low-filled metal layers having a lower filling rate of metal composing the metal layers than oppositely disposed metal layers adjacent to each other in a stacking direction. In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are stacked alternately, the plurality of metal layers include a plurality of thin metal layers having a smaller thickness than oppositely disposed metal layers adjacent to each other in a stacking direction. In a multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers composed mainly of an alloy are stacked alternately, the plurality of metal layers include a plurality of high-ratio metal layers having a higher ratio of a component constituting the alloy than oppositely disposed metal layers adjacent to each other in a stacking direction.

In a multilayer piezoelectric element comprising a plurality of piezoelectric layers and a plurality of metal layers which are alternately stacked one upon another, the metal layers includes a plurality of high resistance metal layers having a higher electrical resistance than adjacent metal layers on the both sides. The high resistance metal layers are regularly arranged so as to interpose a plurality of different metal layers other than the high resistance metal layers. In another multilayer piezoelectric element in which a plurality of piezoelectric layers and a plurality of metal layers are alternately stacked one upon another, at least one layer of the metal layers is formed by a plurality of partial metal layers disposed between the piezoelectric layers.

A multi-layer piezoelectric element having high durability which allows it to increase the amount of displacement of a piezoelectric actuator under high voltage and high pressure and does not undergo a change in the amount of displacement during continuous operation in a high electric field and under a high pressure over a long time period is provided. The multi-layer piezoelectric element comprises a stack of at least one piezoelectric layer and a plurality of internal electrodes consisting of first and second internal electrodes placed one on another, a first external electrode formed on a first side face of the stack and connected to the first internal electrode and a second external electrode formed on a second side face of the stack and connected to the second internal electrode, wherein the bonding strength between the piezoelectric layer and the internal electrode is weaker than the bending strength of the piezoelectric layer.

Multi-layer piezoelectric element and method for manufacturing the same

A laminated piezoelectric device obtained by alternately laminating the piezoelectric layers containing Pb and the conducting layers containing palladium as a conducting component, wherein the piezoelectric layer formed between the two conducting layers has layer regions where Pb and Pd are mixed together in the interfacial portions thereof relative to the conducting layers, the layer regions having a thickness of not larger than 3% of the thickness of the piezoelectric layer. The laminated piezoelectric device is formed by co-firing the Pb-containing piezoelectric layers and the palladium (Pd)-containing layers, the piezoelectric layers therein having a large insulation resistance and good piezoelectric characteristics.

Laminated piezoelectric device

In order to provide a multi-layer electronic component in which the occurrence of delamination between the ceramic layer and the internal electrode is restricted and a method for manufacturing the same, the multi-layer electronic component of the present invention comprises a stack formed by stacking piezoelectric layers and internal electrodes one on another alternately and a pair of external electrodes formed on two opposing side faces of the stack, wherein the internal electrode consists of a first internal electrode connected to the external electrode formed on one of the two side faces and a second internal electrode located between the first internal electrode and connected to the external electrode formed on the other one of the two side faces, and wherein the internal electrodes and the piezoelectric layers are faced in proximity so that a space between them is 2 &#x3bc;m or less over an area occupying 50% or more of the active region where the first internal electrode and the second internal electrode oppose each other.

Multi-layer electronic component and method for manufacturing the same, multi-layer piezoelectric element

Electrostatic chuck

A silicon nitride-silicon carbide composite sintered material which comprises 100 parts by weight of a silicon nitride component containing 92 to 99.5 mol % of silicon nitride including excessive oxygen and 0.5 to 8 mol % of the elements of Group IIIa in the Periodic Table as corresponding oxides thereof and 1 to 100 parts by weight of a silicon carbide component in a dispersed state, wherein the silicon nitride component has an average particle size of 1 .mu.m or less and an average aspect ratio of 2 to 10, and the silicon carbide component has an average particle size of 1 .mu.m or less, moreover, the total amount of Al, Mg, Ca respectively contained in the sintered material as calculated as oxides thereof is 0.5% by weight or less, and a manufacturing method thereof. According to the above-mentioned composite sintered material, it becomes possible to suppress deterioration of strength at 1400.degree. C. and realize excellent creep properties. Therefore, the composite sintered material is applicable not only to structural materials for heat engines such as gas turbines and turbo-rotors but also to other heat resistant materials for various uses.

Silicon nitride-silicon carbide composite sintered material and

Disclosed is a silicon nitride sintered body comprising 70 to 99 mole % of silicon nitride, 0.1 to 5 moles % of a rare earth element oxide and up to 25 moles % of silicon oxide and having a silicon oxide-to-rare earth element oxide molar ratio of from 2 to 25, wherein silicon nitride crystal grains have a fine acicular structure having an average particle major axis of up to 7 .mu.m and an average aspect ratio of at least 3.

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Kirishima, Japan

Masaki Terazono