초록 ▼

A design for manhole frames is provided which provide one or more handholds near the entrance to the manhole so that the ladder rungs can be made lower and the access space at the entrance to the manhole thereby increased. The handhold can be cast into the cover-supporting lip, a detachable horizont

A design for manhole frames is provided which provide one or more handholds near the entrance to the manhole so that the ladder rungs can be made lower and the access space at the entrance to the manhole thereby increased. The handhold can be cast into the cover-supporting lip, a detachable horizontal handle or can be a movable handle which is below the level of the manhole when not in use or extended above ground level when in use.

대표청구항 ▼

1. A manhole frame for a manhole, said manhole frame comprising a vertically extending hollow cylinder open at its top and bottom ends, said manhole comprising a plurality of vertically spaced ladder rungs, said manhole frame comprising an annular lip having an upper manhole cover-supporting surface

1. A manhole frame for a manhole, said manhole frame comprising a vertically extending hollow cylinder open at its top and bottom ends, said manhole comprising a plurality of vertically spaced ladder rungs, said manhole frame comprising an annular lip having an upper manhole cover-supporting surface and extending inwardly from said vertically extending cylinder adjacent the upper edge of said vertically extending cylinder, wherein said manhole frame comprises a handhold to facilitate a person to enter or exit the manhole, said handhold being located in the manhole frame above the uppermost of said ladder rungs close to the upper opening of the manhole, being smaller in width than one of said ladder rungs and protruding a radial distance into the manhole opening less than the inward radial protrusion of said ladder rungs, wherein said handhold is mechanically attachable and detachable to the manhole frame below and adjacent to said annular lip by fastening means and wherein said handhold is horizontally oriented. 2. The manhole frame of claim 1 wherein said handhold protrudes less than about 2 inches into the manhole opening from the edge of said annular lip. 3. The manhole frame of claim 1 wherein the upper surface of said handhold is set flush with or lower than the upper surface of said annular lip. 4. The manhole frame of claim 1 wherein the inner surface of said manhole frame in an area radially outwardly of said handhold is recessed so as to reduce the protrusion of the handhold radially inwardly into the manhole opening while permitting sufficient space for a hand. 5. The manhole frame of claim 1 comprising more than one handhold provided on the manhole frame to facilitate a person to enter or exit the manhole.