| 摘要 |
PROBLEM TO BE SOLVED: To prevent the secondary contact of a runner and contact with a returning bar 3 even contacting with the bar 3 during a race. SOLUTION: The surface 3a on the front side of the bar 3 when viewed from the advancing direction of the runner is arranged on the same line with respect to the fulcrum 10 of the hurdle 1, and the tangential direction of the circular trajectory of the bar 3 is matched with the advancing direction of the runner when an external pressure is applied to the bar 3 and the hurdle 1 falls down. Since the bar 3 falls down drawing the circular trajectory centering on the fulcrum 10 without being projected upwards from an original position, even when the runner contacts the bar 3, just the hurdle 1 falls down and the foot of the runner is not hooked to the falling bar 3 (prevention of secondary contact). Additionally, the falling bar 3 does not return to the original position P, the prevention of the secondary contact is secured. Further, since installation is easily performed when the fulcrum 10 is positioned at a marker 35 displayed on the ground, the installation is facilitated even for an inexperienced worker, an athletic meet is smoothly operated. COPYRIGHT: (C)2007,JPO&INPIT
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