Abstract: The invention is concerned with a new constructive form of hinge for junction and opening of the arms (A) on the front (F) of the glasses, and being the automatic closure of the arms (A), when the glasses aren't being worn. The innovative peculiarity of the invention is to provide the presence of an elastic means (6), operating on a pin (26) of a gear (27), arranged in direct grip with a crown wheel section (11) of a disk (10), where it determines and regulates the movement of the gear (27), the gear (27) itself being solid to the arm (A) to open, whereas the crown wheel section (11) is fixed with the extremity of the hinge of front (F) of glasses.