EARTH AND SAND PENETRATION PREVENTIVE STRUCTURE OF ROTARY GATE

PROBLEM TO BE SOLVED: To make it possible to prevent a rolling stone or earth and sand from penetrating into a clearance between a door of a rotary gate and a river bed housing recessed area and set up the rotary gate even in a middle river basin as well. SOLUTION: A gate main body 10 where a cross section-covered door 12 is provided between a pair of support disks 11, is supported on a horizontal rotary shaft 13 by way of the support disks 11 in such a fashion that the door may be turnable and fixable with a pier at an arbitrary angle which shapes up a rotary gate 1 which forms a housing recessed area 4 which may house the door 12 on an equivalent river bed 2. An earth and sand penetration preventive board 6 is pivoted on the end edge rockably on the river bed 3 on the upper stream side of the housing recessed area 4 which houses the door 12 along the door 12 while it is provided so that the other edge may interfere with a moving area of the door 12. This earth and sand penetration preventive board is designed to cover the clearance 5 between the door 12 and the housing recessed area 4 irrespective of an angle of the door 12.