Mechanism for locking two halves of an underground vault

Claim 2

An underground vault comprising: a first housing having an open end; a second housing having an open end and an annular flange which projects outwardly from the exterior of said second housing; said first housing having a resiliently deformable hook depending from said open end; said flange having an opening extending therethrough, said opening being of a size sufficient to permit said hook to pass through it; said flange having a recess located proximal to said opening, and a camming surface, between said recess and said opening; said hook having means for engaging said recess, said engaging means, upon mutual rotation of said housings, traversing said camming surface to engage said recess and lock said housings together; and said camming surface resiliently deforming said hook in a plane parallel to the direction of motion of said hook as it traverses said camming surface.

Claim 3

An underground vault comprising: a first section having an open end which is bordered by an outwardly projecting annular flange; a second section having an open end which is bordered by an outwardly projecting annular flange; said first and second section flanges being sized and located to permit their mutual confrontation to form an enclosure; said first section flange having a projecting hook; said second section flange having an opening therethrough, a recess spaced from said opening and a camming surface located between said opening and said recess, said surface inclining upwardly in the direction of said recess; said hook comprising a bight, an axially offset segment projecting from said first section flange, and a circumferentially offset segment connecting said axially offset segment and said bight; said opening being sized to permit said hook to pass therethrough; said recess being spaced from said opening no further than said bight is circumferentially offset from said axial offset; said recess having a wall for abutting said bight after said bight is located within said recess to prevent said bight from disengaging from the recess; and said first and second sections being mutually rotatable to permit said bight, after having passed through said opening, to traverse said camming surface and be directed into said recess and abut said wall, said circumferential offset segment bridging said camming surface when said bight is in said recess.

Claim 4

An underground vault comprising: a first section having an open end which is bordered by an outwardly projecting annular flange; a second section having an open end which is bordered by an outwardly projecting annular flange; said first and second section flanges being sized and located to permit their mutual confrontation to form an enclosure; said first section flange having a projecting hook; said second section flange having an opening therethrough, a recess spaced from said opening and a camming surface located between said opening and said recess, said surface inclining upwardly in the direction of said recess; said hook comprising a bight, an axially offset segment projecting from said first section flange, and a circumferentially offset segment connecting said axially offset segment and said bight; said opening being sized to permit said hook to pass therethrough; said recess being spaced from said opening no further than said bight is circumferentially offset from said axial offset; said recess having a wall for abutting said bight after said bight is located within said recess to prevent said bight from disengaging from the recess; and said first and second sections being mutually rotatable to permit said bight, after having passed through said opening, to traverse said camming surface and be directed into said recess and abut said wall, said circumferential offset segment bridging said camming surface when said bight is in said recess.

Claim 5

The device of claim 2 wherein said bight is axially offset from said first section flange a distance less than the largest thickness of said second section flange between said recess and said opening.

Claim 6

The device of claim 2 wherein said bight is axially offset from said first section flange a distance approximately equal to the thickness of the second section flange at the deepest portion of said recess.

Claim 7

The device of claim 2 wherein said bight is axially offset from said first section flange a distance less than the largest thickness of said second section flange between said recess and said opening and a distance greater than the thickness of said second section flange at the lower portion of said camming surface.