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:
Dec. 17, 2024
Filed:
Jun. 30, 2020
Toa Corporation, Hyogo, JP;
Kazuma Asada, Hyogo, JP;
Ryosuke Ozaki, Hyogo, JP;
TOA CORPORATION, Hyogo, JP;
Abstract
Provided is a public address device that facilitates recognizing a sound while performing power control so that input power does not exceed upper-limit supply power of a power source device. Included are a voltage transforming unitthat performs voltage transformation of a direct-current power source input from a power source device; a power amplifierthat amplifies a sound signal using the direct-current power source after the voltage transformation to generate a driving signal that drives an electroacoustic transducer; a power detection unitthat detects input power from the power source device; a threshold holding unitthat holds a power determination threshold Pth corresponding to upper-limit supply power of the power source device; a voltage control unitthat controls an output voltage of the voltage transforming uniton the basis of the input power Pi and the power determination threshold Pth; and a charge accumulation unitthat is connected between the voltage transforming unitand the power amplifier, and supplies a power source to the power amplifierwhen the output voltage of the voltage transforming unitdrops.