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:
Jun. 20, 1995
Filed:
Feb. 02, 1994
Hideto Taka, Nagaokakyo, JP;
Yoshikatsu Maeda, Nagaokakyo, JP;
Murata Manufacturing Co., Ltd., Kyoto, JP;
Abstract
A piezoelectric body polarizing apparatus including a DC power supply 2 for applying a DC voltage to a piezoelectric body 1 to polarize the piezoelectric body 1, an impedance measuring circuit 4 for measuring the change in impedance of the piezoelectric body 1, a high frequency power supply 5, and a DC current blocking filter 3 connected between a high frequency portion, which is constituted by the impedance measuring circuit 4 and the high frequency power supply 5, and the piezoelectric body 1. The DC current blocking filter 3 includes at least a DC current blocking capacitor C.sub.1 and a transient current bypass capacitor C.sub.2 connected between a node A, between the DC current blocking capacitor C.sub.1 and the high frequency portion, and a ground potential.