Modelling of the Hydrostatic Relief in the Cylinder Block of an Axial Piston Pump

The chapter delves into the intricate modelling of hydrostatic relief in the cylinder block of an axial piston pump, a critical component in various high-pressure applications. It begins by introducing the importance and wide use of axial piston pumps in industries such as aerospace, automotive, and construction. The primary focus is on the fundamental groups of assemblies that cause energy losses, particularly the sliding pairs like piston-cylinder and slipper-swash plate. The study considers three distinct designs of the valve plate, each with different overlapping configurations. The core of the chapter involves the detailed modelling of pressure distribution in the main zone of the valve plate, using logarithmic and constant pressure models. This analysis leads to the calculation of unit hydrostatic forces and resultant hydrostatic forces, providing a comprehensive understanding of the forces acting on the cylinder block. The chapter also explores the movement trajectories of these forces, highlighting the imbalance that can cause cylinder block skewing. This imbalance is identified as a design flaw that increases leakage flow rates. The computational models developed offer crucial insights for designers aiming to improve the efficiency and performance of axial piston pumps. The chapter concludes with the recommendation to adopt a spherical valve plate design to mitigate the identified issues, although acknowledging the technological challenges involved.