A pipetting device serves to hold and actuate a detachably mounted syringe having a syringe body and a piston. The device is provided with means for adjusting the volumetric capacity of the syringe. The device comprises two racks and a pinion which is in mesh with both said racks and operable to move...http://www.google.de/patents/US4470317?utm_source=gb-gplus-sharePatent US4470317 - Pipetting device
