초록 ▼

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 fr

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.

대표청구항 ▼

1. A manhole cover assembly, comprising: a manhole cover 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; anda latch assembly, including:

1. A manhole cover assembly, comprising: a manhole cover 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; anda latch assembly, including: a latch shock absorber, including: a latch housing fixedly coupled to the manhole cover, the latch housing defining a latch cylinder,a latch piston slidably coupled to the latch cylinder,a latch rod fixedly coupled to the latch piston, the latch rod extending through the latch housing, anda latch spring positioned within the latch cylinder adjacent the latch piston; anda latch fixedly coupled to the latch rod, the latch selectively rotatable relative to the latch housing between a locked position and an unlocked position, the latch extending radially outward relative to the manhole cover in the locked position so as to prevent the manhole cover from being removed from the manhole frame,wherein, 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. 2. The manhole cover assembly of claim 1, wherein the latch assembly further comprises a latch mounting plate fixedly coupled to, and extending radially outward from, the latch housing, the latch mounting plate coupled to a bottom surface of the manhole cover so that the latch mounting plate is inaccessible from outside of a manhole into which the manhole cover is installed so as to prevent an individual from removing the latch assembly from the manhole cover. 3. The manhole cover assembly of claim 1, wherein the latch assembly further comprises an impact recording disc removably coupled to the latch piston, the impact recording disc structured to measure and record a severity of the pressure applied to the manhole cover. 4. The manhole cover assembly of claim 1, further comprising a roller coupled to the latch, the roller structured to facilitate removal of the manhole cover from the manhole frame. 5. The manhole cover assembly of claim 4, wherein the roller is structured to engage a surface to which the manhole frame is affixed so as to facilitate rolling movement of the manhole cover relative to the surface. 6. The manhole cover assembly of claim 1, wherein the manhole cover further comprises extractor rails extending from a bottom surface of the manhole cover, the extractor rails structured to engage an upper surface of the manhole frame to facilitate removal of the manhole cover from the manhole frame. 7. The manhole cover assembly of claim 1, further comprising a lug assembly fixedly coupled to the manhole cover, the lug assembly comprising: a lug shock absorber, including: a lug housing fixedly coupled to the manhole cover, the lug housing defining a lug cylinder,a lug piston slidably coupled to the lug cylinder,a lug rod fixedly coupled to the lug piston, the lug rod extending through the lug housing, anda lug spring positioned within the lug cylinder adjacent the lug piston,wherein, in response to the pressure applied to the manhole cover, the lug 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. 8. The manhole cover assembly of claim 7, wherein the lug housing is formed integrally within the manhole cover. 9. The manhole cover assembly of claim 7, wherein the lug housing defines an angled surface slidably engageable with an upper surface of the manhole frame to facilitate removal of the manhole cover from the manhole frame. 10. A manhole cover latch assembly, comprising: a latch shock absorber, including: a latch housing structured to be fixedly coupled to a manhole cover, the latch housing defining a latch cylinder,a latch piston slidably coupled to the latch cylinder,a latch rod fixedly coupled to the latch piston, the latch rod extending through the latch housing, anda latch spring positioned within the latch cylinder adjacent the latch piston; anda latch fixedly coupled to the latch rod, the latch selectively rotatable relative to the latch housing between a locked position and an unlocked position, the latch extending radially outward relative to the manhole cover in the locked position so as to prevent the manhole cover from being removed from a manhole frame. 11. The manhole cover latch assembly of claim 10, wherein the latch assembly further comprises a latch mounting plate fixedly coupled to, and extending radially outward from, the latch housing, the latch mounting plate structured to be coupled to a bottom surface of the manhole cover so that the latch mounting plate is inaccessible from outside of a manhole into which the manhole cover is installed so as to prevent an individual from removing the latch assembly from the manhole cover. 12. The manhole cover latch assembly of claim 10, wherein the latch assembly further comprises an impact recording disc removably coupled to the latch piston, the impact recording disc structured to measure and record a severity of the pressure applied to the manhole cover. 13. The manhole cover latch assembly of claim 10, wherein the latch housing defines a first bore extending partially through the latch housing along a longitudinal axis of the latch housing, the first bore defining the latch cylinder, andwherein the latch housing further defines a second bore extending through the latch housing along the longitudinal axis, the second bore defining a latch passage, the latch rod extending through the latch passage, the latch passage having a first diameter slightly larger than a second diameter of the latch rod so as to facilitate rotation of the latch rod relative to the latch passage. 14. The manhole cover latch assembly of claim 13, wherein the latch defines a third bore extending through the latch along the longitudinal axis, the third bore structured to receive the latch rod, andwherein the latch further defines a forth bore extending partially through the latch along a transverse axis perpendicular to the longitudinal axis from an outer surface of the latch to the third bore, andwherein the manhole latch cover assembly further comprises a set screw extending through the fourth bore and into a recess defined by the latch rod so as to fixedly couple the latch to the latch rod. 15. The manhole cover latch assembly of claim 14, wherein the longitudinal axis is a first longitudinal axis,wherein the latch housing defines a detent groove on a bottom surface of the housing, and further defines first and second detents recessed further into the housing from opposite sides of the detent groove,wherein the latch defines a fifth bore extending along a second longitudinal axis, the second longitudinal axis parallel to the first longitudinal axis and spaced radially outward from the third bore, andwherein the latch further includes a detent pin extending through the fifth bore. 16. The manhole cover latch assembly of claim 15, wherein the first detent is structured to receive the detent pin when the latch is in the locked position, andwherein the second detent is structured to receive the detent pin when the latch is in the unlocked position. 17. The manhole cover latch assembly of claim 10, wherein the latch housing defines a cavity extending into the latch housing along the longitudinal axis from an outer surface of the latch housing, andwherein the latch piston includes a tamper-resistant boss formed on an end of the latch piston opposite the latch, the tamper-resistant boss structured to be positioned in the cavity of the latch housing. 18. The manhole cover latch assembly of claim 17, wherein the tamper-resistant boss is engageable only by a specialty tool so as to rotate the latch between the locked position and the unlocked position. 19. The manhole cover latch assembly of claim 10, further comprising a roller coupled to the latch, the roller structured to facilitate removal of the manhole cover from the manhole frame. 20. The manhole cover latch assembly of claim 19, wherein the roller is structured to engage a surface to which the manhole frame is affixed so as to facilitate rolling movement of the manhole cover relative to the surface.