Mixed Lubrication Analysis for Spherical Valve Plate in Piston Rod Driving Type Bento-Axis Type Axial Piston Pump : 1st Report, Mathematical Model

Abstract

In order to investigate lubrication characteristics between rotor and spherical valve plate, a mathematical model of rotor motion has been presented for a piston rod driving type bent-axis-type axial piston pump. The forces and the moments acting on the rotor through the piston rod have been derived from geometric analysis of rotor driving mechanism with the piston rod. An analysis model on mixed lubrication between the rotor and the spherical valve plate has been shown using Average-Flow-Model by Patir-Cheng and the contact theory by Greenwood-Tripp, respectively. In addition, bearing part between the rotor and shaft, supporting element of the rotor, has been regarded as squeeze film bearing. The simulation for the lubrication characteristics, such as minimum film thickness, its occurring position and friction loss between the rotor and the spherical valve plate, will be demonstrated in the paper, part 2.