F01C 1/3442

Rotary-piston machines or engines having the characteristics covered by two or more groups [CPC: F01C1/02], [CPC: F01C1/08], [CPC: F01C1/22], [CPC: F01C1/24] or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group [CPC: F01C1/08] or [CPC: F01C1/22] and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member {the inner and outer member being in contact along one line or continuous surface substantially parallel to the axis of rotation the surfaces of the inner and outer member, forming the working space, being surfaces of revolution}