Detachable close-tolerance connection unit including a fitting screw and a supporting ring

摘要

A detachable close-tolerance connection unit for a component includes a fitting screw including a head, a shank, a threaded portion and a fitting portion. The shank includes a rim element. A supporting ring includes an opening and a narrowing element being located in the opening. The inner diameter of the narrowing element is less than the outer diameter of the rim element. The supporting ring is connectable to the fitting screw with elastic-plastic deformation to reach a pre-assembled position. The narrowing element in the pre-assembled position is located in a portion of the opening facing the head of the fitting screw. The narrowing element in the pre-assembled position is associated with the rim element such that the supporting ring is rotatably and captively connected to the fitting screw. The rim element in the pre-assembled position is located inside of the opening.