Safety blood sampling device

摘要

The blood sampling device has a pointed sharp needle (26) whose one end (34) is used for puncturing the vessel from which blood is to be withdrawn, and whose other end (38) is used for puncturing the septum of a small blood collection tube. The needle (26) is enclosed by a steel cannula (46). The cannula (46) is pretensioned by means of a helical spring (64) in such a way that the tip (34) of the needle (26) is drawn back into the steel cannula (46) in a first position of this cannula. The needle tip (34) emerges from the steel cannula (46) when the latter has been pressed counter to the spring force into its second position. In this state, a blood vessel is punctured by the blood sampling device. As soon as the needle (26) has been inserted into the vessel, the spring (64) brings the steel cannula (46) back into the first position, so that the needle (26) is screened from the outside.