Piston accumulator, vehicle axle and vehicle suspension system with such a piston accumulator

The present invention relates to a piston accumulator (1), preferably hydropneumatic, in particular for vehicle suspension systems, comprising a storage housing (2) and a separating piston (3) which is guided in the storage housing (2) so as to be slidable back and forth in the direction of a housing longitudinal axis (X-X), which separating piston (3) separates a storage chamber (8a;9a) for a hydraulic medium from a pressure chamber (8b;9b) containing, in particular, a pneumatic spring element, in the storage housing (2), wherein the storage housing (2) is formed as part of an axle body (5) of a vehicle axle (31), wherein the axle body (5) is formed with an internally circular-section bore (6), wherein the separating piston (3) is guided in the internal bore (6), as well as a vehicle axle (31) with at least one such piston accumulator (1) and a vehicle suspension system with such a vehicle axle.