PROBLEM TO BE SOLVED: To provide a body sound acquisition device whose casing is contacted with a body surface so as to acquire body sounds, which controls noises from outside without lowering its microphones sensitivity level.SOLUTION: The body sound acquisition device comprises a member 24 for forming a sound collecting part that includes a concave part 240 to form a sealed space for collecting sounds and a surface to be contacted with the body surface, and a holding member 26 provided to abut on a periphery of the member 24 and to be a part of the casing. When a sound impedance of the member 24 is &alpha[Pa s/m], and a sound impedance of the holding member 26 is &beta[Pa s/m], &gamma=1.5×106[Pa s/m], (&alpha-&gamma)2/(&alpha+&gamma)2<(&beta-&gamma)2/(&beta+&gamma)2 is met.COPYRIGHT: (C)2012,JPO&INPIT【課題】筐体を体表に接触させて音を採取するための体内音取得装置において、マイクロフォンの感度を下げることなく、外部からの雑音を抑える。【解決手段】音を採取する時の密閉空間を形成するための凹部240と体表に接する面とを有する集音部構成部材24と、集音部構成部材24の外周に接して設けられ筐体の一部をなす保持部材26とを設ける。集音部構成部材24の音響インピーダンスをα[Pa・s/m]、保持部材26の音響インピーダンスをβ[Pa・s/m]、γ=1.5×106[Pa・s/m]とした場合に、(α-γ)2/(α+γ)2<(β-γ)2/(β+γ)2を満たすように構成した。【選択図】図1
