Heat-responsive aerosol valve

Abstract

A heat-responsive valve construction for use with pressurized containers such as aerosol cans and the like, comprising an annular mounting cup in which there is contained an apertured sealing gasket and also a rigid washer engaged with the gasket. Passing through the cup, gasket and washer is an axially shiftable valve stem having an axial bore in its outer end and having lateral or side orifices intermediate its ends, which communicate with the bore. The outer end of the valve stem also has a plurality of heat-sensing arms extending radially and then axially from the end of the stem in spaced relation thereto, said arms being engaged with the top of the mounting cup. A connector ring joins the ends of the arms where they engage the cup. The other end portion of the valve stem carries a compression spring which is engaged with the rigid washer in the cup and also with an abutment on the stem. The spring applies pressure to the washer, which in turn presses the sealing gasket against the underside of the top wall of the cup. Spring pressure is thus exerted through the stem on the heat-responsive arms, and maintains these in engagement with the top surface of the cup. Under conditions of excessive heat, the arms weaken and yield, being aided by the action of the coil spring, and the latter thereupon shifts the valve stem to move the side orifices thereof completely through the sealing gasket whereby they communicate with the interior of the container to enable discharge of the pressurized liquid therein through the bore of the stem.