Study on the Control Force of a Rodless Type Variable Delivery Axial Plunger Pump

Abstract

By analyzing the kinematics of the variable delivery axial plunger pump without connecting rod, the self-shifting moment which occurs in the tilt-box is determined, and it is shown that the control force of the tilt box which is required for designing the flow control mechanism can be determined by calculation. Main causes of the moment are as follows : (a) The shift of the contact points of plungers towards the upper part of the cam surface. (b) The pressure change from an ideal condition caused by the overlap of the valve surfaces. The oscillation of the tilt box is also explained. The analysis has been verified to be true by the experiment. The methods to reduce the control force are suggested.