GATE DOOR DEVICE

PROBLEM TO BE SOLVED: To provide a gate door device capable of preventing the damage by contact with the exception of the contact surface by surely abutting the door body stopper end against the contact surface of a door stop column for making a moving locus of the door body stopper end as a linear movement crossing a passage section in the direction of a right angle. SOLUTION: A hinge strut 4 and a door stop strut 8 are erected on both side positions of a passage section, the basic end section of a supporting arm 3 is mounted to the hinge strut 4 in a horizontal rotatable manner, a door body 2 is mounted to the pivoting end section of the supporting arm 3 in a horizontal rotatable manner, a guide rail extending in the approximately horizontal direction along the passage section from the hinge strut 4 is provided, a traveling member 7 is fitted to the inside of the guide rail, the traveling member 7 is connected to the hinge end section of the door body 2 in a rotatable manner, a pivoting point of the supporting arm 3 and the door body 2 is used for a reference point P to have the approximately same distance A up to the door stop end of the door body 2 as the distance B up to the pivoting point of the hinge strut 4 of the supporting arm 3 and the distance C up to the pivoting point of the traveling member 7 from the hinge end of the door body 2.