The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 22, 2003
Filed:
Feb. 25, 2002
Mohammed B. Khajavi, Lakewood, CA (US);
Sa'id S. Poosti, Tarzana, CA (US);
Department of Water and Power City of Los Angeles, Los Angeles, CA (US);
Abstract
A method of and system used for venting out buildup of explosive gases in a manhole caused by an explosion and including a support frame, a two inch thick plate member positioned on top of the support frame, a plurality of restraining assemblies and a manhole cover for covering the manhole. The support frame and the plate member are embedded into a street and positioned above the manhole, where openings are aligned with the manhole. Three retaining assemblies are positioned on opposite sides of the manhole cover. Each retaining assembly includes a rod, a stop plate, a coil spring, a support plate and a nut. The rod extends downwardly through the dirt and the horizontal concrete base ledge, where the stop plate, the coil spring, the support plate and the nut are positioned and secured to the other end of the rod.