Method and device for detecting the type of replaceable piston-cylinder units for pipetting or dosing apparatus

Abstract

A method for detecting the type of replaceable piston-cylinder unit mounted in pipetting or dosing apparatus with the help of a code marking on the piston rod head, so as to eliminate the influence of the chain of tolerances piston rod head/piston rod/piston/cylinder bottom/cylinder flange so that, to a certain extent, larger tolerances may be tolerated for the parts of the piston-cylinder units involves generating relative movement between the piston rod head and a detection device, and thereby detecting a reference point on the piston head with the detection device from laterally of the piston head, and generating relative movement between the piston rod head and the detection device and thereby detecting a code marking of the piston rod head in order to determine the type of piston-cylinder unit mounted. Apparatus is provided with which relative movement is produced between the piston rod head and the detection device by a drive device, and during this movement, a reference point on the side of the piston head as well as the code marking are detected by the detection device, and the code marking is evaluated with respect to the reference point. Also, a replaceable pistoncylinder unit for a pipetting or dosing system is provided which has a code marking on the piston rod head by which the type of the piston-cylinder unit is identifiable, the code marking being detectable by a detector positioned laterally of the piston rod head when the the piston-cylinder unit is mounted in a pipetting or dosing apparatus.

Dependencies are inferred from the claim text.