Manhole extension assembly
AssigneesMargaret T. Hall, James B. Turner, Jr.
InventorJohn R. Hall
Life of this patent
Estimating the term…
Abstract
Plastic extender rings for manholes are produced and are seated on the top ring of a manhole by the use of caulking or other adhesive material. The manhole cover, which is elevated by the plastic ring or rings from the old pavement level to a new pavement level, renders the manhole cover less noisy to traffic and seated more evenly. Recessed or notched portions of the rings receive the asphalt to arrest rotational and upward movement of the rings. Composite adapter rings are provided to adapt an off size manhole top rings, to a standard size manhole cover. Plastics are employed which will not melt at the application temperature of asphalt but will soften somewhat to conform better to the contour of the manhole cover and/or underlying manhole top ring.
Claims14
A manhole extension assembly comprising in combination with a manhole cover and a manhole having a top ring embedded in pavement of a plastic extender ring member having a bottom surface mounted in concentric relationship on the upper end portion of said top ring of said manhole below pavement level, said ring member having an upper surface which has an annular recessed seat therein for receiving and seating said manhole cover with its upper level at about the level of said pavement, said ring member having circumferentially spaced peripheral outwardly opening recesses which receive the pavement therein to prevent appreciable rotation of said ring member and for overlapping of a portion of said ring member below the upper surface of said ring member to prevent appreciable upward movement of said ring member.
Dependencies are inferred from the claim text.