Patent ID: 7811236

Claim:
A microsampler puncturing system for collecting a body fluid sample from a body part, comprising: a sample collection unit having a piercing element, and a puncturing instrument having: a drive, wherein the sample collection unit is movable on a movement path in a piercing and retraction movement for piercing the piercing element into skin of the body part, creating a piercing wound and withdrawing the piercing element thereafter, a setting device configured to set a defined puncturing depth of the piercing wound, and a control device configured to control the piercing and retraction movement, the piercing and retraction movement including the following sequentially executed movement phases: a forward phase, in which the piercing element is moved in a puncturing direction and pierced to the defined puncturing depth, a retraction phase, in which the piercing element is partially withdrawn by a retraction distance and is decelerated toward an end of the retraction phase, in such a manner that the piercing element projects into the skin to a residual puncturing depth, and a collecting phase, in which a body fluid sample is withdrawn by the sample collection unit, via the piercing element projecting into the skin and being stationary, such that the residual puncturing depth is constant, or moving opposite to the puncturing direction, wherein a mean value of the residual puncturing depth corresponds to the time integral of the residual puncturing depth from the beginning of the collecting phase to the end of the collecting phase divided by the duration of the collecting phase, the setting device is adapted to set the defined puncturing depth independently of the mean value of the residual puncturing depth and the setting device is adapted to set the mean value of the residual puncturing depth independently of the defined puncturing depth.