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:
Jul. 13, 1999
Filed:
Aug. 25, 1997
Yasuhei Shimada, Tokyo, JP;
Shingo Kawashima, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A piezoelectric transformer is driven with the PWM driving method by means of a driving voltage with a waveform obtained by time-dividing a first frequency with a binary pulse of a second frequency lower than the first frequency. A harmonic component of said second frequency component contained in said first frequency component can be suppressed by decreasing a slope of an envelope of said driving voltage waveform. A parasitic vibration of the piezoelectric transformer in the piezoelectric transformer-inverter controlled with the PWM system can be suppressed by controlling such inverter as described above and construction of the piezoelectric transformer support mechanism can be simplified.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile