Patent ID: 7314094

Claim:
A device for revealing, responsive to heat, a component recessed in the surface of a room, said device including: a) a barrel comprising a cylindrical wall defining a bore therein for encircling the component, said cylindrical wall having a first end having a flange projecting radially outward therefrom, and a second end opposite the first end; b) a helical compression spring surrounding the cylindrical wall, said spring having a first end pressing against the flange, and having a second end; c) a spring retainer attached to the second end of the cylindrical wall and engaging the second end of the spring to hold the spring in compression, said retainer including a release mechanism activating at a predetermined safety temperature, said mechanism maintaining compression of the spring prior to activating, d) wherein the retainer comprises a bar extending radially outward from the cylindrical wall and at least part way across the bore at the second end of the sleeve, and wherein the release material comprises low temperature solder attaching the bar to the second end of the cylindrical wall.