The present invention provides an improved trocar assembly for use in creating an incision in a patient. The trocar of the present invention includes a unique piercing apex, which eases the insertion process, and an internal tip protector to protect the patient and medical personnel from accidental puncture...http://www.google.se/patents/US5246425?utm_source=gb-gplus-sharePatent US5246425 - Trocar and cannula assembly
