Proportional valve

Abstract

The present invention relates to a proportional valve (), particularly for fluid dispensing devices, comprising a main body () in which an inlet conduit () for an inlet fluid to said proportional valve () and an outlet conduit () for a fluid leaving said proportional valve () are defined, said inlet conduit () and said outlet conduit () being in fluid communication with each other, said proportional valve () comprising at least one shutter element () arranged between said inlet conduit () and said outlet conduit () adapted to intercept said fluid, said shutter element () comprising a movable fluid sealing element () adapted to intercept said fluid at one of said inlet conduit () and said outlet conduit () and a lever element () associated at a first end with said movable fluid sealing element () and at a second end with an actuator device (), said lever element () being hinged about said main body () at a fulcrum point () arranged between said first end and said second end of said lever element (), said actuator device () being configured for moving said lever element () of said shutter element () around said fulcrum point () so as to move said movable fluid sealing element () between an opening position in which the fluid communication between said inlet conduit () and said outlet conduit () is allowed and a closing position in which the fluid communication between said inlet conduit () and said outlet conduit () is prevented. According to the invention, said actuator device () comprises an actuator element () made of a shape memory material which can be operated progressively to move said lever element () of said shutter element () around said fulcrum point () so as to proportionally vary the degree of opening of said movable fluid sealing element () between said opening position and said closing position, and vice versa, the variation of said degree of opening of said movable fluid sealing element () allowing the regulation of the flow rate of said fluid exiting from said outlet conduit ().