Patent ID: 9534369
Date: 2017-01-03
CPC Classifications: E03F

Claim:
1. An inlet of an underground reservoir comprising: a flow portion, wherein water flows; a drop portion transporting the water to the underground reservoir from the flow portion; and an inlet portion having a multiple-stage structure to generate a vortex in the water to be transported to the drop portion, wherein the multiple-stage structure includes a plurality of multiple-stage boards, and wherein the plurality of multiple-stage boards include a first horizontal board, a second horizontal board and a first vertical board connecting the first horizontal board and the second horizontal board and downwardly extending from the first horizontal board to be perpendicular to the second horizontal board, thereby forming a step, and wherein the plurality of the multiple-stage boards are inclined from the flow portion to the drop portion, are parallel to the direction of the water flow thereon, and converge adjacent to the drop portion.