Radial piston type hydraulic motor - has wide pistons in thick holder ring to take up gap between rotor and stator

摘要

The motor has a cylindrical casing with which a cylindrical rotor revolves on an eccentric shaft. Radial pistons are held in an outer ring round the rotor and caused to reciprocate by the movement of the rotor. The pistons run on rollers on the rotor and are sealed to it by sliding vanes. Their sides are supported in the outer ring by further rollers and they are sealed to the ring by circumferentially sliding vanes. The size of the pistons is such that they take up much of the gap between the rotor and stator and thus reduce consumption of liq.