05522833 is referenced by 56 patents and cites 14 patents.

A retractable obturator trocar with a puncturing tip is provided. Preferably the obturator includes a safety shield covering the puncturing tip in an unarmed position and permitting the tip to extend distally from the safety shield in an armed position. The obturator preferably includes a spool retracting mechanism which causes the distally extended obturator to retract into the safety shield when a force is applied to the puncturing tip. The obturator may also be manually disengaged. The safety shield and obturator preferably extend out of the distal end of the cannula whether the trocar is armed or unarmed.

Title
Retractable obturator for a trocar
Application Number
8/297456
Publication Number
5522833
Application Date
August 29, 1994
Publication Date
June 4, 1996
Inventor
Richard C Smith
Loveland
OH, US
James Voegele
Cincinnati
OH, US
Randy R Stephens
Fairfield
OH, US
Agent
Susan M Schmitt
Assignee
Ethicon Endo Surgery
OH, US
IPC
A61M 5/178
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