Kabushiki Kaisha Toyota Chuo Kenkyusho

Denso Corporation

Toyota Jidosha Kabushiki Kaisha

Toyoda Koki Kabushiki Kaisha

Hiroaki Makino

Nobuo Kamiya

Mitsuru Asai

Katsunori Yamada

Takao Tani

Shin Tajima

Takashi Yamamoto

Akira Fujii

Nobuo Abe

Toshiatsu Nagaya

Kazumasa Takatori

Shigetaka Wada

Kaori Fujita

Hirokatsu Mukai

Hiroshi Hohjo

Yoichi Kobane

Takahiko Homma

Jun Sugiyama

Hideo Kamiya

Kiyotaka Kinoshita

Shiro Kuwahara

Toshiharu Mikami

Tsuguto Takeuchi

Toshitada Wada

An object of the present invention is to provide a piezoelectric stack substantially free from deterioration in performance and having high reliability, and a production method thereof. A piezoelectric layercomprising PZT and an internal electrode layerare alternately stacked; the grain boundary-filling factor of a Pb-based glass in the crystal grain boundary of the piezoelectric layeris 95% or more; in producing a piezoelectric stackin which a piezoelectric layercomprising PZT and an internal electrode layerare alternately stacked, unfired sheets for the piezoelectric layerare stacked to produce an unfired stacked body, the unfired sheet containing Pb in excess of the stoichiometric ratio in PZT and having printed thereon an electrically conducting paste for the internal electrode layer, and the unfired stacked body is fired in an oxygen atmosphere having an oxygen concentration of 40 to 100 vol % such that the grain boundary-filling factor of a Pb-based glass in the crystal grain boundary inside the piezoelectric layeris 95% or more.

Piezoelectric stack and production method of piezoelectric stack

A physical sensor having a pressure sensing layer having such property that electrical resistance is changed by application of a stress, and electrical insulating layers which are integrally formed on opposite two surfaces of the pressure sensing layer, respectively, wherein the pressure sensing layer has a matrix comprising glass, and an electrically conductive particle having electrical conductivity and dispersed in the matrix and preferably, the electrically conductive particle includes RuO, and a thickness of the pressure sensing layer is 1 &#x3bc;m to 200 &#x3bc;m, and it is preferable that one pair of electrodes are disposed on the pressure sensing layer.

Physical sensor

A noble metallic firing tip includes a protruding portion which is formed partly on its outer circumferential surface so as to protrude in the direction substantially normal to the axis of a center electrode. The protruding portion is disposed in confronting relationship via a discharge gap with a distal end of an opposed portion of a ground electrode far from its leg portion.

Spark plug

A dynamic quantity sensor device capable of measuring a dynamic quantity at a high precision and securing insulation of a pressure sensing body easily. This dynamic quantity sensor includes a pressure sensing body composed of composite ceramics in which a material having a pressure resistance effect is dispersed on a matrix made of an electrical insulation ceramic material and a pressure receiving body having an electrical insulation characteristic and disposed on a pressure receiving surface of the pressure receiving body, wherein the pressure sensing body and the pressure receiving body are integrated with each other.

Mechanical quantity sensor element, load sensor element, acceleration sensor element, and pressure sensor element

A sensor material for measuring physical parameters capable of configuring a sensor capable of directly measuring a high value of physical parameters such as high stress or high pressure without employing a pressure resistance container. The sensor material for measuring static and dynamic physical parameters includes a matrix made of an electrically insulating ceramic material, and piezoresistance materials which are dispersed in the matrix so as to be electrically continuous to each other.

Material for measuring static and dynamic physical parameters

A piezoelectric ceramic composition, having a tetragonal perovskite structure and represented by a general formula Pb,Sr,(Zr,Ti,Sb,Mn,)O,wherein Pb and Sr are assumed to occupy A site, Zr, Ti, Sb and Mn are assumed to occupy B site, and a molar ratio of A site/B site atoms of (a&plus;b)/(c&plus;d&plus;e&plus;f) is more than 1.00 to 1.03, preferably 0.01 to 0.03.

Piezoelectric ceramic composition for use in an ultrasonic wave motor

A piezoelectric material includes a PZT ceramic, and a noble metal component. The noble metal component is added to the PZT ceramic in an amount of 0.35 parts by volume or more with respect to 100 parts by volume of the PZT ceramic, and is at least one element selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt and Au, or is an alloy of silver (Ag) and the noble metal element. A piezoelectric element includes a pair of external electrodes, at least a pair of piezoelectric layers, and a conductive layer. The piezoelectric layers are formed of the PZT ceramic, and are disposed between the external electrodes. The conductive layer is formed of the noble metal component, and is insulated from the external electrodes. The piezoelectric layers and the conductive layer are formed lamellarly, and are laminated alternately in a direction connecting the external electrodes.

Piezoelectric material and piezoelectric element

This invention provides a piezoelectric ceramic composition having large field-induced strain under high compressive stress, small temperature dependence of strain, and high energy conversion efficiency even at high temperatures. The composition is represented by;

Piezoelectric ceramic composition

A joined assembly of a ceramic member and a metallic member having a hollow cylindrical portion which is open at one end thereof, and closed at the other end, or bottom thereof. The ceramic member has a portion fitted in the cylindrical portion in such a way that any stress acting axially upon the surface of the ceramic member may be reduced at least in the vicinity of the open end of the cylindrical portion. The two members are joined together by shrinkage fitting with at least one brazing material filling the clearance between the two members, or by chemical bonding.

Joined assembly of ceramic and metallic materials

Growing community of inventors

Aichi, Japan

Hiroaki Makino