Two-chamber blood taking syringe

摘要

The blood taking syringe has a main cylinder with a screw-on front cap which has a cannula attachment and a rubber plate through which the cannula projects. At the rear end of the cylinder is a further screw cap in which is an opening for the piston rod. The main cylinder encloses the first chamber (10) and the second chamber (12) is in the piston itself. The piston is formed as a cylinder within which is the second chamber which has anticoagulating agents in it. A cannula from the second chamber projects into the first chamber and has a side opening in it which is covered by a rubber tube which acts as a valve to prevent back flow of blood to prevent an undesired mixing of the blood between the two chambers.