Abstract: A fusible link having two body members separably coupled to one another and normally prevented from separating by a collapsible strut. One body member has an opening in which the other body member is slideably accommodated, such other body member having an abutment which bears against the body at one marginal edge of the opening. The strut is accommodated within the opening and reacts between the two body members to preclude movement of the slideable body to a position in which the abutment can pass through the opening in the other body. The strut includes a eutectic alloy which melts when its temperature rises to a predetermined level. Melting of the eutectic alloy permits the overall length of the strut to shorten by an amount sufficient to permit the abutment on the slideable body to pass through the opening in the other body and effect separation of the bodies.

Abstract: A fire extinguisher sprinkler head construction has a fitting adapted to be coupled to a water line and having a passage therein through which water may flow and impinge upon a deflector. The water passage normally is sealed by a closure and a collapsible strut, the latter including a eutectic member which liquifies upon reaching a predetermined temperature. The eutectic member is sandwiched between a pair of thermally insulating members, also forming part of the strut, and is engaged by a thermally conductive member which functions as a heat collector.

Abstract: A fire protection sprinkler head construction comprises a frame having at one end a water passage therethrough which normally is closed by a seal maintained in passage sealing position by a thermally sensitive strut which collapses in response to a predetermined increase in its temperature and enables water to flow through the passage. At the other end of the frame is a deflector against which water flowing through the passage impinges and is deflected outwardly in a spray. Encircling the deflector is an annular distributor having a plurality of circumferentially spaced apart blades which intercept water deflected outwardly by the deflector. The blades are twisted at their root ends and bent at their free ends to cause water impinging upon the blades to be divided into relatively large droplets and distributed circumferentially.