PROBLEM TO BE SOLVED: To provide an oxygen concentrator in which low vibration, low noise and a simple structure can be achieved, and power consumption can be reduced by using a rotary cylinder device of which the compressor has a combination of a rotary motion with a reciprocating linear motion.SOLUTION: A compressor 105 includes a rotary cylinder device 300 which forms a compressed-air-generating part 105a and a negative-pressure-air-generating part 105b alternately, by reciprocating motion of linear-motion pistons 301 and 302 within the cylinder 321 which are linked to a core-deviated cylindrical body 303 revolving around a crank axis 308 which is deviated from the axial core of a driving axis 331.COPYRIGHT: (C)2011,JPO&INPIT【課題】コンプレッサに回転運動と往復直線運動を組み合わせたロータリ式シリンダ装置を用いることにより、低振動・低騒音で構造が簡略化でき、消費電力も低減することが可能な酸素濃縮装置を提供する。【解決手段】コンプレッサ105は、駆動軸331の軸芯に対して偏芯したクランク軸308を中心に回転する偏芯筒体303に連繋する直動ピストン301,302がシリンダ321内を往復動することで圧縮空気発生部105aと負圧空気発生部105bとを交互に形成するロータリ式シリンダ装置300を備えている。【選択図】図12