Trocar assembly

• US 4,601,710 A
• Filed: 08/06/1984
• Issued: 07/22/1986
• Est. Priority Date: 08/24/1983
• Status: Expired due to Term

• Current Assignee: United States Surgical Corporation (Medtronic Plc)
• Original Assignee: Endotherapeutics Corporation (Medtronic Plc)
• Inventors: Moll, Frederic H.
• Primary Examiner(s): Pellegrino, Stephen C.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/638,048
• Time in Patent Office: 715 Days
• Field of Search: 604/158, 604/164-165, 604/169, 604/272-274, 128/305, 30/162, 30/151-152
• US Class Current: 604/164.12
• CPC Class Codes: A61B 17/3474 Insufflating needles, e.g. Veress needles
• CPC Class Codes: A61B 17/3496 Protecting sleeves or inner probes; Retractable tips for protecting body piercing guide needles A61M25/0612
• CPC Class Codes: A61B 2017/00473 Distal part, e.g. tip or head A61B2017/00464 takes precedence
• CPC Class Codes: A61B 2017/346 with wings
• CPC Class Codes: A61B 2090/08021 of the patient or his organs

Abstract

A trocar assembly (70) formed from a trocar tube subassembly (74) and a separable, interfitting trocar subassembly (72). The trocar tube assembly includes a head (112) having a bore (120) into which a trocar tube (116) is fitted and a manually operated slide valve assembly (118) mounted transversely of the bore in the head. The valve has a bore (134) through it that may be aligned with the bore in the head by movement of the valve. The trocar subassembly includes a head (76) that has a bore (92) extending partly through it in which a trocar obturator (82) and a concentric tubular shield (86) are mounted such that the shield is capable of limited axial movement relative to the obturator between a normal, extended position in which the shield effectively covers the piercing tip (84) of the obturator and a retracted position in which the tip is exposed. The obturator and shield are inserted through the bore in the trocar tube subassembly head, the slide valve bore and the trocar tube. The bore in the slide valve has a radial tooth (136) in it that engages a slot (138) in the shield to reversibly lock the shield in its extended position when the slide valve is in its normal position. The valve is depressed manually to disengage the tooth to allow axial movement of the shield or separation of the trocar subassembly from the trocar tube subassembly.

Claims

1. A trocar assembly comprising:

(a) an elongate trocar obturator having a piercing tip at its front end;

(b) and an elongate trocar tube in which the trocar obturator is housed;

(c) a tubular protective shield mounted concentrically around the trocar obturator and being axially movable relative to the trocar obturator between a normally extended position and a retracted position; and

(d) biasing means acting on the rear end of the protective shield, whereby the shield is forced to said retracted position to expose the piercing tip when the trocar is being inserted through the wall of a body cavity and is biased by said means to said extended position to shield the piercing tip once the trocar has pierced the wall.

2. The trocar assembly of claim 1 wherein the assembly includes:

(e) means for reversibly locking the shield in said extended position.

3. The trocar assembly of claim 2 wherein the means for reversibly locking the shield in said extended position is a manually operable slide valve that has a bore through which the obturator and shield extend, the bore has a radial locking tooth that is adapted to engage a slot in the wall of the shield, the valve being slidable transversely to the shield from a normally locked position in which the tooth is engaged in the slot to an unlocked position in which the tooth is disengaged, whereby the shield may be moved axially to said retracted position.

4. The trocar assembly of claim 1, wherein the assembly includes:

(e) means for limiting the axial movement of the shield relative to the obturator to positions between the extended position and retracted position.