Temperature-sensitive snap-action valve

Claim 1

A fire extinguishing system automatic thermally actuated sprinkler valve assembly comprising a base, a fluid conduit on said base adapted for connection to a source of high pressure fluid, valve means in said fluid conduit for controlling flow therethrough, a splash plate assembly secured beneath said base aligned with said fluid conduit, a temperature-sensitive actuator mounted on said base, and a spring linkage assembly operatively connecting said actuator with said valve means, said spring linkage assembly comprising a valve member pivotally mounted on said base and operatively connected with said valve means, an actuator member pivotally mounted on said base for rotation about an axis spaced from and parallel to the pivot axis of said valve member, said actuator operatively engaging said actuator member to permit rotation of said actuator member in response to temperature variations, and a tension spring having one end thereof attached to said actuator member at a point remote from its pivot axis, the opposite end of said spring being connected to said valve member at a point remote from its pivot axis, said spring urging said actuator member in rotation toward said actuator, said spring normally urging said valve member in rotation to hold said valve means fully closed, said spring passing over center upon a predetermined temperature condition to urge said valve member in the opposite rotational direction, thereby fully opening said valve means with a snap action and permitting high pressure fluid to strike said splash plate assembly.