Abstract: An underground structure cover comprises a cover body (10) and a receiving frame (20) arranged so that the cover body is fitted in and supported by the receiving frame in the manner that an inclined surface (11) of the outer circumference of the body meets an inclined surface (21) of the inner circumference of the frame. The inclined surfaces (11, 21) each have an upper inclined surface (11a, 21a) and a lower inclined surface (11b, 21b), and the lower inclined surfaces (11b, 21b) are steeper than the upper inclined surfaces (11a, 21a). The body (10) is fitted in and supported by the part (20) at the upper inclined surfaces (11a, 21a) and the lower inclined surfaces (11b, 21b). By this, the body is prevented from being wedged into the frame too deeply and also from becoming inclined with respect to the frame or riding up.

Abstract: An underground structure cover comprises a cover body (10) and a receiving frame (20) arranged so that the cover body is fitted in and supported by the receiving frame in the manner that an inclined surface (11) of the outer circumference of the body meets an inclined surface (21) of the inner circumference of the frame. The inclined surfaces (11, 21) each have an upper inclined surface (11a, 21a) and a lower inclined surface (11b, 21b), and the lower inclined surfaces (11b, 21b) are steeper than the upper inclined surfaces (11a, 21a). The body (10) is fitted in and supported by the part (20) at the upper inclined surfaces (11a, 21a) and the lower inclined surfaces (11b, 21b). By this, the body is prevented from being wedged into the frame too deeply and also from becoming inclined with respect to the frame or riding up.

Abstract: A cover assembly includes a support frame (20) fixed to a utility access hole and a rounded cover (10) fitted into the support frame. The support frame is provided in its upper portion with an S-curved inner peripheral surface (20b) having a convex curved surface portion (21) and a concave curved surface portion (22) that continues to the convex curved surface portion and is formed thereabove. The cover has an S-curved peripheral surface (10b) that is substantially complementary in shape to the S-curved inner peripheral surface of the support frame. When the access hole is closed by the cover, the cover is smoothly fitted into the support frame due to a guide function of the S-curved inner peripheral surface of the support frame.

Abstract: A cover assembly includes a support frame (20) fixed to a utility access hole and a rounded cover (10) fitted into the support frame. The support frame is provided in its upper portion with an S-curved inner peripheral surface (20b) having a convex curved surface portion (21) and a concave curved surface portion (22) that continues to the convex curved surface portion and is formed thereabove. The cover has an S-curved peripheral surface (10b) that is substantially complementary in shape to the S-curved inner peripheral surface of the support frame. When the access hole is closed by the cover, the cover is smoothly fitted into the support frame due to a guide function of the S-curved inner peripheral surface of the support frame.