WILLIAM SOUTHWELL O'DONNELL
Pilots at Fall Riv Ct, Houston, TX
License number
Texas A1408104
Issued Date
May 2015
Expiration Date
May 2016
Category
Airmen
Type
Authorized Aircraft Instructor
Address
Address
311 Fall River Ct, Houston, TX 77024
Professional information
Portable Ladder Assembly
US Patent:
4892170, Jan 9, 1990
Filed:
Apr 27, 1989
Appl. No.:
7/344060
Inventors:
William P. O'Donnell - Nassau Bay TX
Assignee:
Avanti International - Webster TX
International Classification:
B65D 9010, E06C 136
US Classification:
182100
Abstract:
A portable ladder assembly comprises a base, a supporting bracket, and a single rail ladder. The ladder assembly is particularly well suited for safely allowing human entry into a chamber with a confined area entry, such as a conventional manhole. The base member includes arms positionable on each side of the manhole entry for engaging a support surface, such as the ground, to prevent tipping of the ladder assembly. The bracket includes a rail receiving slot and a plurality of vertically spaced and downwardly directed rung receiving slots on opposing sides of the rail receiving slot. The ladder may be safely supported at various selected depths within the manhole by fitting the rail in selected rungs within their corresponding slots. The ladder assembly of the present invention does not significantly reduce the entry opening into the chamber, and may be safely used without being structurally dependent upon the manhole.