A variable volume chamber device is disclosed. The chambers may be defined by the space between four pivotally connected vanes contained within two side plates. The vanes may be connected so as to create a sealed interior chamber that may be used as a combustion chamber in an internal combustion engine, or as a pumping chamber in a pump or compressor. The four vane assembly may also form additional variable volume chambers between the vanes and a surrounding structure. The plurality of variable volume chambers may be interconnected to progressively act on a working fluid.

A variable volume chamber device is disclosed. The chambers may be defined by the space between four pivotally connected vanes contained within two side plates. The vanes may be connected so as to create a sealed interior chamber that may be used as a combustion chamber in an internal combustion engine, or as a pumping chamber in a pump or compressor. The four vane assembly may also form additional variable volume chambers between the vanes and a surrounding structure. The plurality of variable volume chambers may be interconnected to progressively act on a working fluid.