and hinged to the inner member

Full Title

Rotary-piston pumps specially adapted for elastic fluids (with fluid ring or the like F04C19/00; rotary-piston pumps in which the working-fluid is exclusively displaced by one or more reciprocating pistons F04B) > having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members > having both the movement defined in group F04C18/02 and relative reciprocation between the co-operating members > with vanes hinged to the outer member and reciprocating with respect to the inner member > and hinged to the inner member