Fixing assembly and fixing device

A fixing device, comprising a turnover box and a fixing assembly, the fixing assembly comprising:

• a connecting sleeve;
• a spike piece rotatably connected to the connecting sleeve;
• and
• an elastic piece, wherein one end of the elastic piece is connected to the connecting sleeve, and the other end of the elastic piece is connected to the spike piece, the elastic piece at least spirally winds around and holds an outer peripheral wall of the spike piece, in case that the spike piece rotates relative to the connecting sleeve in a direction opposite to the spiral winding direction of the elastic piece, the elastic piece generates elastic deformation which has an included angle with the axial extension direction of the spike piece to form a spiral convex elastic structure;
• wherein
• the turnover box is provided with an accommodating groove and a mounting hole which are communicated;
• the connecting sleeve is located in the mounting hole and is fixedly connected to the turnover box, the spike piece and the elastic piece are both located in the accommodating groove, and one end of the spike piece protrudes from an outer side of the turnover box.