20160053457 | Controlled Pressure Release Manhole Cover Assembly - A manhole cover assembly includes a manhole cover and a latch assembly. The manhole cover is movable between a seated position in which the manhole cover is supported on a seat of a manhole frame, and an unseated position in which the manhole cover is displaced relative to the seat of the manhole frame. A shock absorber includes a housing fixedly coupled to the manhole cover. The housing defines a cylinder. A piston is slidably coupled to the cylinder. A rod is fixedly coupled to the piston. A spring is positioned within the cylinder adjacent the piston. A latch is fixedly coupled to the rod. In response to a pressure applied to the manhole cover, the latch assembly is configured to permit limited displacement of the manhole cover relative to the seat of the manhole frame, and to controllably dissipate energy relating to the pressure. | 02-25-2016 |