The mechanism of the invention has a rotary element pivotably arranged in a lower part (1) of the housing onto a central shaft on the upper part (3) of said rotary element snap elements (5) are pivotably arranged around a central transmission element (6). One ends (5b) of said snap elements (5) engage with a projection (6a) of the central transmission element (6) and their locking parts (5c) engage with an external lock (9) provided with teeth (9a) on the inner circumferential side.
