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:
May. 05, 1992
Filed:
Jul. 24, 1990
Applicant:
Inventor:
Yoshiharu Nakaji, Yokosuka, JP;
Assignee:
Nissan Motor Company, Limited, Yokohama, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G10K / ;
U.S. Cl.
CPC ...
381 71 ;
Abstract
A system for lowering noise level in a vehicular cabin produces an acoustic vibration canceling noise creative vibration induced in synchronism with an engine revolution. The system generates a rectangular wave signal having 50% duty cycle. The system includes means for producing a periodic signal having an interval half of a period of the noise created by vibration. The signal level of the rectangular signal is switched between HIGH and LOW levels alternatively at the time of occurrence of the periodic signal.