Safety trocar
First Claim
Patent Images
1. A trocar comprising:
- (a) A cannula assembly comprising a cannula and a cannula housing defining an internal cannula passage;
(b) a trocar assembly adapted to cooperate with said cannula assembly, said trocar assembly comprising a sharp trocar tip, an obturator shaft, and a trocar housing, said trocar tip and at least a portion of said obturator shaft being configured and dimensioned for entry into said internal cannula passage;
(c) releasable obturator means associated with the obturator shaft which releasably maintains the trocar tip in an extended position relative to said cannula;
(d) means for releasing the releasable obturator means; and
(e) biasing means for retracting the trocar tip from said extended position to a retracted position in response to release of the releasable obturator means.
1 Assignment
0 Petitions
Reexamination
Accused Products
Abstract
A safety trocar is provided in which the cutting tip is withdrawn into the cannula in response to counterforce being removed from the cutting tip, e.g., by the tip entering a body cavity. The cutting tip is maintained in the exposed positioned by a mechanism associated with the oburator shaft, and is automatically withdrawn into the cannula under the force of a spring when the first mechanism is released by a second mechanism associated with the oburator. Penetration force is maintained at a minimum and safe and efficacious trocar entry is facilitated.
-
Citations
20 Claims
-
1. A trocar comprising:
-
(a) A cannula assembly comprising a cannula and a cannula housing defining an internal cannula passage; (b) a trocar assembly adapted to cooperate with said cannula assembly, said trocar assembly comprising a sharp trocar tip, an obturator shaft, and a trocar housing, said trocar tip and at least a portion of said obturator shaft being configured and dimensioned for entry into said internal cannula passage; (c) releasable obturator means associated with the obturator shaft which releasably maintains the trocar tip in an extended position relative to said cannula; (d) means for releasing the releasable obturator means; and (e) biasing means for retracting the trocar tip from said extended position to a retracted position in response to release of the releasable obturator means. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A trocar comprising:
-
(a) a cannula assembly comprising a cannula and a cannula housing defining an internal cannula passage; (b) a trocar assembly adapted to cooperate with said cannula assembly, said trocar assembly comprising a sharp trocar tip, an obturator shaft, an outer trocar housing and an inner trocar housing, said inner trocar housing and outer trocar housing being reciprocally mounted to each other, and said trocar tip and at least a portion of said obturator shaft being configured and dimensioned for entry into said internal cannula passage; (c) releasable obturator means associated with the obturator shaft which releasably maintains the trocar tip in a first extended position relative to said cannula; (d) means for releasing the releasable obturator means; and (e) biasing means for retracting the trocar tip to a second retracted position in response to release of the releasable obturator means. - View Dependent Claims (16, 17)
-
-
18. A method for inserting a trocar, comprising:
-
(a) advancing an obturator and a trocar tip to expose said trocar tip from a cannula, said trocar tip being maintained in said exposed position by means associated with said obturator; (b) pressing said trocar tip against a body wall, said body wall thereby exerting a counterforce against said trocar tip; (c) entering said trocar tip into a body cavity, thereby removing said counterforce form said trocar tip and actuating release means associated with said obturator shaft to release said maintaining means, whereby said trocar tip is automatically withdrawn into said cannula under the action of a biasing means. - View Dependent Claims (19, 20)
-
Specification