Electrically controlled proportional valve

Abstract

An electrically controlled proportional valve provides for precise control of fluid flow using an armature which is positioned at the center of a spider. The armature is supported and biased axially by a plurality of springs that radiate outwardly from it. The springs support the armature for elastic movement in the axial direction, and hold it biased against a first port, so that the armature functions as a valve element, which normally closes that port. A magnet coil is positioned so that when energized it applies force to the armature, overcoming the bias of the springs and drawing the armature away from the first port. During armature movement the plurality of springs are deflected at their outer diameter against an angled surface on the valve case. The increased spring surface area that rests against the valve case causes a proportional relationship between the movement of the armature and the magnetic field created by the magnet coil. A spring-loaded seal in the armature compensates for dimensional instability of the elastomeric seal material and the armature assembly.