Patent ID: 7713481

Claim:
An automatic pipetting unit with a replaceable pipetting head, comprising a pipetting head; two head rails located on opposite sides of said pipetting head; two horizontal guide channels located in the interior of said pipetting unit for supporting said head rails; a frame; two frame-mounted, double-sided slider crank mechanisms, frame-mounted by means of a pivot and positioned within an internal gear, and vertically arranged in said pipetting unit; each double-sided slider crank mechanism including two crank mechanisms each connected to a common articulated thrust joint by a thrust couple; said horizontal guide channels being formed in said articulated thrust joint and said crank mechanisms being connected indirectly to a head cover of said pipetting unit; so that with the opening and closing motion of said head cover said two slider crank mechanisms are moved between two end positions so that the pipetting head can be moved vertically between a lower end working position and an upper end replacement position.