MECHANISM FOR OPENING AND CLOSING SHIELD IN HELMET

PROBLEM TO BE SOLVED: To reduce the extent of protrusion of a shield from the surface of a helmet by attaching two centers of rotation of the shield in both left and right sides of the helmet, changing over the centers of rotation in the course of rotation of the shield and preventing the shield from separating from the hat body surface of the helmet. SOLUTION: This mechanism is obtained by supporting shafts 3' on both lateral parts of a shield 3 for closing a window hole of a helmet 1 on the outside of the helmet 1 with supporting shafts 4 and 5 which are two centers of rotation so as to be freely rotatable in the vertical directions. The supporting shaft 4 is fitted into a tracklike hole 6 and the supporting shaft 5 is fitted into a circular arc hole 7. The supporting shaft 4 preferably has an elastic piece 8 producing spring actions in the radial direction. The shaft 5 is moved so that the distance between the centers of the shafts 4 and 5 shown in the figure describes a circular arc always equal to the distance between the centers of the shafts 4 and 5 when the shaft 4 is located at the right end of the hole 6.