The invention relates to a retracting device for a leaf of a door or a window, comprising a housing, a piston which is arranged in a receiving area of the housing and which is urged by a spring, and a shaft which is mounted in the housing and which interacts with the piston, an actuating arm for the leaf being arranged on the shaft in a non-rotatable manner. At least one first driving element is arranged on the shaft, the head surface of said driving element forming a freewheel device with a freewheel region, wherein an arrangement of the piston or a tooth of a toothing of the piston slides on the freewheeling region so as to decouple the shaft from the piston.