US Patent 10375469 Speaker box

A speaker box, includes a housing and a speaker unit accommodated in the housing. The speaker unit includes a diaphragm for forming a front sound cavity cooperatively with the housing. The box further includes a sound transmitting channel communicating the front sound cavity and outside, a front cavity of the speaker box formed by the front sound cavity and the sound transmitting channel, a through hole formed in the housing corresponding to the front cavity, and an elastic cover plate disposed on the housing and covering the through hole. A resonance frequency of the elastic cover plate is greater than a working frequency range of the speaker unit.