The device comprises a body ( 2 ) and placed therein a needle assembly ( 1 ) and a push button ( 3 ) located in the upper portion of the body ( 2 ), whereas the needle assembly ( 1 ) has in its lower portion a sheathed piercing needle ( 5 ), and the push button ( 3 ) has in its upper portion a press surface, and between the body ( 2 ) and the needle assembly ( 1 ) a return spring ( 27 ) is placed. The push button ( 3 ) is coupled with the needle assembly ( 1 ) by means of abutting surface elements ( 15 , 44 ), whereas during the movement of the push button ( 3 ) and after resting the needle assembly ( 1 ) on the element ( 20 ) of the body ( 2 ) and after performing the full-depth piercing, one of the abutting surface elements ( 15 , 44 ) bends, releasing the needle assembly ( 1 ) from the thrust of the push button ( 3 ), whereupon the needle assembly ( 1 ) retracts to the inside of the body by means of the return spring ( 27 ). The return spring ( 27 ) consists of plastic flat springing beams, preferably "L" or "U" shaped, whereas at least one end the return spring ( 27 ) is connected with the body ( 2 ).
