Triple Controls of Piston Pumps with Mixed Stages

The paper re rts upon numerical simulation tests carried out on a variable displacement axial piston pump equipped with multiple automatic controls. The swashplate control circuit includes two hydraulic stages with two tandem three way v es (the pressure compensator and the flow limiter) and a servo with digital control circuit acting as a torque or/and speed limiter. The dynamic response of the system is evaluated both separate and combined control functions. Th effect of changes in the design parameters of the digital control is discussed with reference to the system respo se to various load demands.