In a floating cup axial piston machine, each piston has its own cuplike cylinder, floating on a barrel plate. On average the cups and the barrel rotate at the same rotational speed. A closer look at the kinematics of the floating cup principle however reveals that the cups make a small movement on the barrel plate. The size of this cup trajectory is strongly dependent on the tilt angle between the barrel and the rotor. Furthermore, the non-uniformity of the joint between the barrel and the rotor shaft can create an angular difference between the cup and the barrel position. This article will focus on the combined effect of the barrel tilt angle and the non-uniformity on the cup movement.

Keywords: axial piston machine, floating cup principle, construction, cup movement