Instrument for the production of a sample of body fluid for analysis by piercing the skin with a lancet cutting element (12) having a skin piercing tip (7) said instrument (11) being provided with : - a housing (13), - a cutting drive with lancet (14) inside said housing (13) to be connected to a cutting element with lancet (12) and for actuating a cutting element with lancet (12) connected to it in a puncture movement in which the cutting element with lancet (12) moves, after the triggering of the puncture movement, in a direction of the puncture until it reaches a point (P) of maximum displacement and in a reverse direction after it has reached the point (P) of maximum displacement, - a pressure ring (1) that surrounds a skin contact hole (4) and which is adapted to be pressed against the skin, in which the instrument (11) comprises a pressure force control device for controlling the pressure force between the pressure ring (1) and the skin at the time of the triggering of the puncture movement, so that it is at least 3 N, and the pressure ring (1) - is a part of a pressure piece (42) comprising a peripheral surface part (50) accessible from the outside, surrounding the pressure ring (1) and recessed from the pressure ring (1), - protrudes in the direction of the puncture from the part of the peripheral surface (50) of the pressure piece (42) by a distance (h) of at least 0.5 mm, - has a surface area in narrow ring shape that surrounds the skin contact hole and that supports at least 70% of the forces acting between the instrument and the skin during practical use, and - has at least part of its circumference a width ( b) no more than 1.5 mm.Instrumento para la producción de una muestra de líquido del cuerpo para el análisis mediante la perforación de la piel con un elemento de corte con lanceta (12) que tiene una punta de perforación de la piel (7) estando provisto dicho instrumento (11) de: - un alojamiento (13), - un accionamiento de corte con lanceta (14) en e
