Automatic drainage cover

The Automatic Drainage Cover realizes the whole drainage process through self-driving gravity drainage structure. When the rainwater gathers in large quantities, it will flow into the chamber under the well cover, and the will be pulled by gravity and cause the chamber to rotate down along the spiral structure, then the connected drainage cap will also be dropped and unfolded, so that it can drain automatically quickly and efficiently. In addition, the product can ensure the safety of pedestrians and vehicles in any state for the whole well cover does not need to be fully deployed in drainage.