The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 10, 1998
Filed:
Oct. 10, 1997
Murata Manufacturing Co., Ltd., Kyoto, JP;
Abstract
A piezoelectric ceramic which maintains a high piezoelectric property in a composition having MPB structure and has an excellent ability for stabilizing the resonant frequency is provided. The piezoelectric ceramic has a solid solution expressed by the general expression xPbTiO.sub.3 --(1-x) PbZrO.sub.3 as its main component. The value of x in the above general expression causes the piezoelectric ceramic to have a composition having the morphotropic phase boundary structure. A ceramic having a spinel type structure is dispersed within the structure of the piezoelectric ceramic. The amount of the ceramic having the spinel type structure existing in the structure is set at about 5 volume % or less. Co.sub.2 TiO.sub.4, Mn.sub.3 O.sub.4, Fe.sub.3 O.sub.4, Mg.sub.2 TiO.sub.4 and a ceramic having a compound spinel type structure which is a solid solution of them can be used as the ceramic having the spinel type structure.