Patent · US Revoked

Speaker device

US9820053B2 · kind B2 · utility

0Cited by
0References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 15, 2015
Grant dateNov 14, 2017
Priority date
Expiry dateJan 15, 2035

Classification

  • Technology area (CPC —)General

Abstract

Acoustic conversion efficiency is improved and a stable signal reproduction operation is ensured. Provided is a speaker device including: a magnet; a yoke attached to the magnet and at least one sub-plate that is separated from the main plate in an axial direction of the central axis; a coil bobbin formed in a tubular shape and changeable in the axial direction; a voice coil wound around an outer circumferential surface of the coil bobbin, at least a portion of the voice coil being disposed in a main magnetic gap formed between the main plate and the yoke; a vibration plate having an inner circumferential portion connected to the coil bobbin; and a magnetic fluid filling at least one sub-magnetic gap formed between the sub-plate and the yoke, wherein a through-hole positioned in the sub-magnetic gap filled with the magnetic fluid is formed in the coil bobbin.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.