Abstract: The invention relates to a drive device for linear movement of an infusion syringe piston of an infusion syringe disposed on an infusion pump comprising a drive head unit including a main bearing means for supporting the infusion syringe piston, a fixing means for securing the infusion syringe piston to the main bearing unit as well as means for triggering the fixing means and comprising an advancing means for the drive head unit including a motor-drivable advancing spindle and a multi-part advancing spindle nut having at least one radially movable nut shell, wherein the drive head unit additionally comprises detecting means for detecting the infusion syringe piston ahead of the main bearing means, the detecting means including a multi-threshold sensor unit comprising an at least two-stage upstream detection means for detecting different positions of the infusion syringe piston ahead of the main bearing means.

Abstract: The invention relates to a drive device for linear movement of an infusion syringe piston of an infusion syringe disposed on an infusion pump comprising a drive head unit including a main bearing means for supporting the infusion syringe piston, a fixing means for securing the infusion syringe piston to the main bearing unit as well as means for triggering the fixing means and comprising an advancing means for the drive head unit including a motor-drivable advancing spindle and a multi-part advancing spindle nut having at least one radially movable nut shell, wherein the drive head unit additionally comprises detecting means for detecting the infusion syringe piston ahead of the main bearing means, the detecting means including a multi-threshold sensor unit comprising an at least two-stage upstream detection means for detecting different positions of the infusion syringe piston ahead of the main bearing means.