Patent ID: 6858015

Claim:
A blood withdrawal system for diagnostic purposes, comprising a housing with an outlet opening for the tip of a lancet, which is movable in the housing along a predetermined puncture path, a lancet guide for guiding the lancet on the predetermined puncture path and a lancet drive by which a movement of a drive element is converted into a puncturing movement after the actuation of a trigger, whereby the lancet is moved with high speed along the predetermined puncture path in puncturing direction until its tip protrudes from the outlet opening, wherein the lancet drive comprises a plural lever coupling mechanism forming a connection between the drive element and the lancet during the puncturing movement and comprising two levers connected to each other by means of a first swivel joint, one of the levers is coupled to the lancet by means of a second swivel joint, and the second lever comprises a third swivel joint at its end facing away from the lancet, and the plural lever coupling mechanism is moved, during the puncturing movement, from a first bent position via a straight position corresponding to the maximum puncturing depth to a second bent position, and is moved, during a cocking movement, from the second bent position via the straight position to the first bent position, the freedom of movement of the lancet is limited during the cocking movement in such a manner that the lancet tip does not protrude from the outlet opening, and the third swivel joint is connected to a moveable bearing part which during the cocking movement moves inside the housing in a direction opposite to the puncturing direction, and the freedom of movement of which is limited during the puncturing movement in the direction opposite to the puncturing direction.