Patent ID: 7472878
Filing Date: 2009-01-06
Classification: E04G

Abstract:
1. A lowering device of a support structure, the device comprising: a plate having an opening, a vertically extending elongated hole, and a lower projection; a first bolt having a first end penetrating through said elongated hole and a second end mounted to the support structure; a second bolt having a first end penetrating through said elongated hole and a second end mounted to the support structure; a first latch part disposed at said plate to surround said first end of said first bolt; and a second latch part disposed at said plate to partially surround said first end of said second bolt, wherein said first and said second latch parts cooperate to form a locking mechanism which maintains the support structure in a first elevated position and, in response to a force of gravity, lowers the support structure into a second, lowered position, said first and said second bolts being raised within said elongated hole in said first position and being lowered within said elongated hole in said second position.