US 7,712,995 B2Granted

Method of controllably venting gases generated by explosions in a manhole space

OwnerDavid Stadlerinventor

Life of this patent

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Abstract

A method for controllably releasing venting gases from a manhole space around the perimeter of a manhole cover by allowing the manhole cover to rise up in stages upon development of upward forces in an explosion to vent gases developed by the explosion while being restrained from being completely blown free except under extreme conditions. A lock body mounts a latch slide which has an outer end and which can be extended to prevent removal of the manhole cover. When a shear pin fails the lock body pivots down, to a limited extent, and a secondary shear pin can also be included allowing the cover to be blown completely free upon development of pressures of a great magnitude. A slotted skirt is used to direct venting gas flow so as to retard the inflow of free air and attenuate the explosion.

Claims4

Dependent claims

A method of controllably venting gases generated by explosions in a manhole space having a manhole cover extending over said manhole space received within an opening in a frame structure, comprising:

arranging locking features on a perimeter of said manhole cover spaced apart from each other and extending radially outwardly to be aligned beneath portions of a said frame structure extending around said opening and with a vertical clearance between said locking features and said portions of said structure so as to allow said manhole cover to rise up in the event of an explosion to clear said structure and thereby create an annular gap between the underside of the cover and the top of said structure allowing venting of gases from said manhole space;
and
preventing further vertical movement of said manhole cover by interengagement of said locking features and said structure portions upon continued upward vertical movement of said manhole cover to thereby prevent said manhole cover from being blown completely free of said structure and able thereafter to drop down over said opening in said frame structure.

Dependencies are inferred from the claim text.

Facts

Application: 12/357,525Filed 22 Jan 2009 · division
Priority: 12 Jun 2006
Published: US 2009/0154993 A118 Jun 2009
Granted: 11 May 2010
Term ends: Not estimatedThe source records don’t support an estimate.

Classification3 codes

E02D 29/1427
Covers for manholes or the like; Frames for covers: locking devices
E02D 29/1436
Covers for manholes or the like; Frames for covers: with overflow or explosion control means, e.g. check or relief valves
E02D
Foundations

Family

Application60/812,757Us provisional application · filed 12 Jun 2006
Application60/889,553Us provisional application · filed 13 Feb 2007
Application60/921,975Us provisional application · filed 6 Apr 2007
Application11/761,711Parent of this division · filed 12 Jun 2007
US 2009/0154993 A1Pre-grant publication · published 18 Jun 2009
US 7,484,908 B2Parent of this division
US 2007/0286677 A1Published application
US 7,712,995 B2This patent

From the US filing history. Foreign family members aren’t listed.