| 摘要 |
A coupling structure of a manhole cover and a manhole frame is provided to promote easy management and safety by preventing a manhole cover and a manhole frame from being separated or damaged by the sewage or rainwater flowing backward, and making a manhole cover opened automatically according to the quantity or pressure of the sewage or rainwater flowing backward and closed automatically after sewage or rainwater flows backward completely. A coupling structure of a manhole cover and a manhole frame is formed by forming a hinge projection(11) to one side of a manhole frame(1), forming a groove(21) on a manhole cover(2) to be opened upward, erecting the manhole cover vertically and pushing an opening of the groove into the hinge projection of the manhole frame completely, and then putting a cap(3) on the groove of the manhole cover. If sewage or rainwater flows backward, the manhole cover is opened from the hinge projection by the quantity or pressure of sewage or rainwater to drain off the sewage or rainwater flowing backward smoothly and to make the manhole cover opened stably without separation or damage and closed to the original location with dead weight after flowing backward. |
