Patent ID: 6953301

Claim:
A cover assembly for a utility access hole comprising a support frame fixed to the utility access hole and having a circumferential wall that defines a central hole, at least an upper portion of which has a round shape in plan, and a rounded cover that is removably fitted into the upper portion of the central hole of the support frame to close the utility access hole, wherein: the circumferential wall of said support frame has an S-curved inner peripheral surface in an upper portion thereof, said S-curved inner peripheral surface having a convex curved surface portion that is curved convexly with respect to the central hole of said support frame and a concave curved surface portion that continues to said convex curved surface portion and is formed above said convex curved surface portion and curved concavely with respect to the central hole of said support frame; and said cover has an S-curved peripheral surface that is substantially complementary in shape to the S-curved inner peripheral surface of the circumferential wall of said support frame, said S-curved peripheral surface having a concave curved surface portion that is substantially complementary in shape to the convex curved surface portion of the S-curved inner peripheral surface of said support frame and a convex curved surface portion that continues to said concave curved surface portion and is formed above said concave curved surface portion to have a substantially complementary shape to the concave curved surface portion of the S-curved inner peripheral surface of said support frame.