Nippon Soken, Inc.

Denso Corporation

Hiroshi Matsuoka

Eturo Yasuda

Yasushi Sawada

Makoto Nakae

Tetsuya Kato

Yasuyuki Satou

Hiroyuki Yoshida

Yoichi Kotanshi

Hiroyuki Satou

Syuuichi Nakano

A gas sensor element is composed of a sensor section, a heater section, and a porous protective layer. The sensor section is composed of a solid electrolyte layer and a pair of electrodes. The heater section heats the sensor section to activate it. The porous protective layer covers surfaces of the sensor section and the heater section of the gas sensor element in a gas sensor which is exposed to a target detection gas to be detected. The porous protective layer is made of a mixture of hydrophobic heat resisting particles having a contact angle of not less than 75&#xb0; to a drop of water, and the hydrophilic heat resisting particles having a contact angle not more than 30&#xb0; to a drop of water. A gas sensor equipped with the above gas sensor element is also disclosed.

Gas sensor element and gas sensor equipped with the same

A piezoelectric ceramic having a basic composition expressed by a ternary PbTiO.sub.3 O.sub.3 --PbTiO.sub.3 --PbZrO.sub.3 solid solution, wherein part of the Pb is substituted by Sr, the Pb(Y.sub.0.5 Nb.sub.0.5)O.sub.3 is present in an amount of more than 42 mol % of the ternary solid solution, and the ceramic contains Mn.sub.2 O.sub.3 in an amount of 0.01 wt % or more and less than 0.5 wt %. The piezoelectric ceramic provides a material for a piezoelectric device which operates without substantially varying in output, and thereby mitigates the load on the drive circuit, under a large temperature variation.

Piezoelectric ceramic

A laminated piezoelectric transducer, comprising a laminate of a plurality of piezoelectric plates with paste electrodes inserted therebetween and bonding the plates together. Rows of metal extrusions are made by electroless plating onto the paste electrodes on the peripheral outer surface of the laminate. Each row of the metal extrusions is formed onto and electrically connected to alternate paste electrodes, so that by electrically connecting each row of the metal extrusions, the laminate of the piezoelectric plates is electrically connected in parallel. This laminated piezoelectric transducer allows the formation of the paste electrodes on the entire or at least substantially the entire main surfaces of the piezoelectric plates, and eliminates the need for the usual metal plate electrodes inserted between the piezoelectric plates.

Laminated piezoelectric transducer

Growing community of inventors

Kariya, Japan

Hiroshi Matsuoka