Valve for fluids having a diaphragm shutter controlled by shape memory means acting also as defrosting means

Abstract

Described herein is a valve for fluids, liquids or dusts, which can be used to particular advantage for controlling openings for passage of cooling air in refrigerating apparatuses or the like. The valve comprises a diaphragm open/close element having a central part and a peripheral edge connected, respectively, to a central support and to a peripheral support. Said supports are axially displaceable with respect to one another between a first relative end position and a second relative end position corresponding, respectively, to the open condition and to the closed condition of the valve, or vice versa. The relative displacement in an axial direction of said first and second supports is controlled by shape-memory means, including at least one shape-memory wire, which extends at least in part along the periphery of the diaphragm and is activated by electrical supply means. The heating of the wire is exploited to remove any possible formation of ice or frost that might tend to prevent correct movement of the diaphragm.