Device indicating loosening of nut

The invention relates to a device indicating the loosening (1) of a rotary element (2) of a screw-and-nut system, the rotary element being intended for being screwed by a rotation movement about a longitudinal direction (D), the rotary element comprising a portion with a polygonal cross-section in a plane normal to the longitudinal direction, the portion with polygonal cross-section defining a plurality of planar surfaces (21, 22, 23, 24, 25, 26), the indicator device comprising a body (3) intended for being mounted on the rotary element, a marking element (4) extending radially, rigidly connected to the body so as to indicate the angular position of the rotary element, and at least one spring (31, 32, 33, 34, 35, 36) rigidly connected to the body so that, when the body is mounted on the portion with polygonal cross-section, each spring exerts a radial bearing force on a corresponding planar surface of the rotary element. 本发明涉及指示螺钉-螺母系统的旋转元件(2)的松动的装置(1)，所述旋转元件旨在通过围绕纵向(D)的旋转运动而被旋拧，所述旋转元件包括在与所述纵向垂直的平面内具有多边形截面的部