Combination manhole and fill

Claim 2

A tank manhole closure means for selectively sealing a fill aperture therein comprising, an elongated planar strongback hinged at one end to the manhole closure means at one side of the aperture for swingiNg movement in a vertical plane over the aperture, said strongback having a fill cover on its underside for selective sealing engagement with the aperture when the strongback is swung over the aperture to a closed position, and an elongated substantially planar latch arm hinged at one of its ends to the tank at the opposite side of the aperture for swinging movement in said vertical plane toward and away from the strongback, said latch arm having its one end bifurcated forming an opening for receiving the free end of the strongback therethrough, said latch arm having an elongated depending ridge transversely disposed on its underside adjacent the inner edge of the opening, said strongback having an elongated transverse recess formed in its top side adjacent its free end and extending below the surface of such top side for receiving said ridge therein when the strongback free end is inserted in the latch arm opening thereby locking the strongback and its cover over the fill aperture in closed sealed position when the latch arm is positioned over the strongback in closed position, the entrance surface of said recess being an inclined convex curved camming surface on which the ridge slides and is thus cammed into the recess, said latch arm ridge comprising a downwardly extending elongated transversely disposed hook portion formed in the latch arm adjacent the inner edge of the latch arm opening.

Claim 3

The structure of claim 1 wherein said strongback has a second elongated transverse recess formed in its top side parallel to the first-named recess and disposed adjacent the free end of the strongback outwardly of the first-named recess, said second recess forming a safety stop for receiving said latch arm ridge if such ridge becomes disengaged from the first-named recess.

Claim 4

The structure of claim 2 wherein a projection having camming surfaces on both sides thereof is interposed between the recesses to provide facile clamping movement of the latch arm ridge from one recess to the other, thereby effecting an over-center action to compress the cover and insure a tight seal in said closed position.

Claim 5

The structure of claim 1 and further including a pair of strongback hinge lugs secured to the manhole closure at said one side of the aperture, the hinged end of said strongback being bifurcated with such bifurcated end being hinged to said strongback hinge lugs.

Claim 6

The structure of claim 1 and further including a pair of latch arm hinge lugs secured to the manhole closure at said opposite side of the aperture with the bifurcated end of the latch arm being hinged to said latch arm hinge lugs.

Claim 7

The structure of claim 1 wherein said latch arm is of elongated rectangular configuration in plan, said latch arm having a handle for manual grasping on the free end thereof.

Claim 8

The structure of claim 1 wherein said cover includes an annular gasket retainer of lesser diameter than the aperture, an annular disc of greater diameter than the aperture and spaced from and disposed above the gasket retainer, and an annular gasket of greater diameter than the aperture and interposed between the retainer and the disc in clamped relation, whereby the gasket contacts the periphery of the aperture and the disc imparts a semi-resilient sealing action to the cover when it is clamped on the aperture.

Claim 9

The structure of claim 7 and further including a springwell disposed centrally on the cover, said disc being threadedly secured to the springwell, said springwell having a vertical bore open at the top, said strongback having a sleeve fitting on its underside and extending partially into the top of the bore, and a coil spring disposed in the bore and compressed between the bottom wall of the springwell and said sleeve fitting, thereby imparting a resilient clamping effect on the cover when it is locked over the aperture.

Claim 10

The structure of claim 7 and further including a vent valve disposed centrally thereon.

Claim 11

The structure of claim 1 wherein the cover is of single plate constructiOn, said cover having a dovetail gasket attached to the periphery thereof.

Claim 12

A tank manhole closure means for selectively sealing a fill aperture therein comprising, an elongated planar strongback hinged at one end to the manhole closure means at one side of the aperture for swinging movement in a vertical plane over the aperture, said strongback having a fill cover on its underside for selective sealing engagement with the aperture when the strongback is swung over the aperture to a closed position, and an elongated substantially planar latch arm hinged at one of its ends to the tank at the opposite side of the aperture for swinging movement in said vertical plane toward and away from the strongback, said latch arm having its one end bifurcated forming an opening for receiving the free end of the strongback therethrough, said latch arm having an elongated depending ridge transversely disposed on its underside adjacent the inner edge of the opening, said strongback having an elongated transverse recess formed in its top side adjacent its free end and extending below the surface of such top side for receiving said ridge therein when the strongback free end is inserted in the latch arm opening thereby locking the strongback and its cover over the fill aperture in closed sealed position when the latch arm is positioned over the strongback in closed position, the entrance surface of said recess being an inclined convex curved camming surface on which the ridge slides and is thus cammed into the recess, said latch arm ridge comprising a downwardly extending transversely disposed flange formed in the latch arm adjacent the inner edge of the latch arm opening.

Claim 13

A tank manhole closure means for selectively sealing a fill aperture therein comprising, an elongated planar strongback hinged at one end to the manhole closure means at one side of the aperture for swinging movement in a vertical plane over the aperture, said strongback having a fill cover on its underside for selective sealing engagement with the aperture when the strongback is swung over the aperture to a closed position, and an elongated substantially planar latch arm hinged at one of its ends to the tank at the opposite side of the aperture for swinging movement in said vertical plane toward and away from the strongback, said latch arm having its one end bifurcated forming an opening for receiving the free end of the strongback therethrough, said latch arm having an elongated depending ridge transversely disposed on its underside adjacent the inner edge of the opening, said strongback having an elongated transverse recess formed in its top side adjacent its free end and extending below the surface of such top side for receiving said ridge therein when the strongback free end is inserted in the latch arm opening thereby locking the strongback and its cover over the fill aperture in closed sealed position when the latch arm is positioned over the strongback in closed position, the entrance surface of said recess being an inclined convex curved camming surface on which the ridge slides and is thus cammed into the recess, said latch arm ridge comprising a downwardly extending transversely disposed flange formed in the latch arm adjacent the inner edge of the latch arm opening.

Claim 14

A tank manhole closure means for selectively sealing a fill aperture therein comprising, an elongated planar strongback hinged at one end to the closure means at one side of the aperture for swinging movement in a vertical plane over the aperture, said strongback carrying a cover on its underside for selective sealing engagement with the aperture when the strongback is swung over the aperture to a closed position, an elongated planar latch arm hinged at one of its ends to the closure means at the opposite side of the aperture for swinging movement in said vertical plane toward and away from the strongback, said latch arm having its one end bifurcated forming an opening for receiving the free end of the strongback therethrough, said latch arm having an elongated ridge transversely disposed on its underside adjacent the inner edge of the opening, said strongback having an elongated transverse recess formed in its top side adjacent its free end for receiving said ridge therein when the strongback free end is inserted in the latch arm opening thereby locking the strongback and its cover over the aperture in closed sealed position when the latch is positioned over the strongback in closed position, said latch arm ridge including a downwardly extending elongated transversely disposed hook portion formed in the latch arm adjacent the inner edge of the latch arm opening, said strongback having a second elongated transverse recess and disposed adjacent the free end of the strongback outwardly of the first-named recess, said second recess forming a safety stop for receiving said latch arm ridge if such ridge becomes disengaged from the first-named recess, there being a camming surface interposed between the recesses to provide facile movement of the latch arm ridge from one recess to the other, a pair of strongback hinge lugs secured to the closure means at said one side of the aperture, the hinged end of said strongback being bifurcated with such strongback bifurcated end being hinged to said strongback hinge lugs, and a pair of latch arm hinge lugs secured to the closure means at said opposite side of the aperture with the bifurcated end of the latch arm being hinged to said latch arm hinge lugs, said latch arm being of elongated rectangular configuration in plan, said latch arm having a handle for manual grasping on the free end thereOf.

Claim 15

A tank manhole closure means for selectively sealing a fill aperture therein comprising, an elongated planar strongback hinged at one end to the closure means at one side of the aperture for swinging movement in a vertical plane over the aperture, said strongback carrying a cover on its underside for selective sealing engagement with the aperture when the strongback is swung over the aperture to a closed position, an elongated planar latch arm hinged at one of its ends to the closure means at the opposite side of the aperture for swinging movement in said vertical plane toward and away from the strongback, said latch arm having its one end bifurcated forming an opening for receiving the free end of the strongback therethrough, said latch arm having an elongated ridge transversely disposed on its underside adjacent the inner edge of the opening, said strongback having an elongated transverse recess formed in its top side adjacent its free end for receiving said ridge therein when the strongback free end is inserted in the latch arm opening thereby locking the strongback and its cover over the aperture in closed sealed position when the latch is positioned over the strongback in closed position, said latch arm ridge including a downwardly extending elongated transversely disposed hook portion formed in the latch arm adjacent the inner edge of the latch arm opening, said strongback having a second elongated transverse recess and disposed adjacent the free end of the strongback outwardly of the first-named recess, said second recess forming a safety stop for receiving said latch arm ridge if such ridge becomes disengaged from the first-named recess, there being a camming surface interposed between the recesses to provide facile movement of the latch arm ridge from one recess to the other, a pair of strongback hinge lugs secured to the closure means at said one side of the aperture, the hinged end of said strongback being bifurcated with such strongback bifurcated end being hinged to said strongback hinge lugs, and a pair of latch arm hinge lugs secured to the closure means at said opposite side of the aperture with the bifurcated end of the latch arm being hinged to said latch arm hinge lugs, said latch arm being of elongated rectangular configuration in plan, said latch arm having a handle for manual grasping on the free end thereOf.