Back to results
US 7,009,513 B2Granted
Inherently deployable warning to alarm of an opening into the top of a sub-grade structure
AssigneeCarson Industries LLC
InventorNguyen Thai Dang
Life of this patent
Estimating the term…
Abstract
A signal to warn of the open condition of a sub-grade vault whose lid may be open or missing. A spring-loaded placard is held down in the vault by a closed lid and raises above the opening by its own stored energy when the lid is open or missing.
Claims11
In combination:
- a sub-grade structure having a peripheral sidewall including an upper rim forming an open top above a cavity inside said wall;
- a cover adapted to fit in said open top to close said cavity;
- and
- a warning device so disposed and arranged as to give visual notice of the open condition of said open top when the cover is raised or removed, said device comprising a hinge plate mounted to said upper rim inside said cavity;
- a hinge pin rotatably fitted in said hinge base;
- a spine on said hinge pin rotatable between an upper deployed position and a lower position below said rim;
- a placard mounted to said spine;
- and bias means biasing said spine toward its deployed position;
- whereby with the cover laid atop said rim, the spine and placard will be held in the cavity, spring-loaded against the cover, and when the cover is raised or removed, the spine and placard will rise above the rim.
6 more elements
Dependencies are inferred from the claim text.