Concealed sprinkler with drop down deflector assembly, and improved fusible valve lever assembly

摘要

A concealed sprinkler with drop down deflector assembly includes a pair of frame arms which resemble a tuning-fork, there being a gap between the free end portions of the arms. As a result, the arms are not subject to assembly loads or system pressure loads. The drop down deflector assembly is mounted on the end portions of the arms. A preferred valve assembly includes a valve and a compound lever arrangement for holding a rigid thermal responsive element, such as a frangible glass bulb, and for adjusting compressive pre-load on the valve without loading the frame arms.