An adjustment device for regulating the torque of a hydrostatic piston machine with adjustable swept volume, comprises an adjustment piston delimiting an adjustment chamber, a regulation valve defining a valve bore and including a valve slide positioned in the valve bore that controls inflow and outflow of pressure medium, and first and second feedback springs configured to exert feedback force on the valve slide in first and second displacement directions dependent on a position of the adjustment piston. The device further includes a regulation spring configured to exert a force on the valve slide in a second displacement direction. During an adjustment of the adjustment piston in a direction of maximum swept volume of the piston machine, beyond a particular position of the adjustment piston, the first and second feedback springs exert an increased force on the valve slide determined only by a spring constant of the first feedback spring.