EP0479130A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Safety trocar
Assignee: United States Surgical Corp
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Filing: 1991-09-26
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Granted: —
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Expires: 2011-09-26
Abstract
Abstract A safety trocar (10) is provided in which the cutting tip (12) is withdrawn into the cannula (14) in response to counterforce being removed from the cutting tip, e.g., by the tip entering a body cavity.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tip is maintained in the exposed positioned by a mechanism associated with the obturator shaft, and is automatically withdrawn into the cannula under the force of a spring (64) when the first mechanism is released by a second mechanism associated with the obturator. Penetration force is maintained at a minimum and safe and efficacious trocar entry is facilitated.
Inventors
- 👤 David T. Green
- 👤 Guy D. Thomas
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-22 23:38
CPC Classifications
A; A61; A61B; A61B17/00; A61B17/34; A61B17/3494; A61B17/3496; A61B90/00; A61B90/08; A61B2090/0801; A61B2090/08021
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
88 words
A trocar (10) comprising: a) a cannula assembly (18) comprising a cannula (14) and a cannula housing (20); b) a trocar assembly (16) comprising a sharp trocar tip (12), an obturator shaft (78) and a trocar housing; c) means associated with the obturator shaft which releasably maintains the trocar tip in an extended position; 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.
Claim 2
Dependent Claim
88 words
A trocar (10) comprising: a) a cannula assembly (18) comprising a cannula (14) and a cannula housing (20); b) a trocar assembly (16) comprising a sharp trocar tip (12), an obturator shaft (78) and a trocar housing; c) means associated with the obturator shaft which releasably maintains the trocar tip in an extended position; 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.
Claim 3
Dependent Claim
41 words
A trocar as claimed in claim 1, wherein said cannula is lanced or notched to form an internal shelf and said internal shelf is adapted to cooperate with said releasable obturator means to maintain said trocar tip in said extended position.
Claim 4
Dependent Claim
25 words
A trocar as claimed in claim 1 or 2, wherein said releasable obturator means comprises a latch and a spring biasing said latch radially outward.
Claim 5
Dependent Claim
21 words
A trocar as claimed in claim 1, 2 or 3, wherein said means for releasing the obturator means comprises a pawl.
Claim 6
Dependent Claim
25 words
A trocar as claimed in any one of the preceding claims, wherein said trocar tip is mounted to an extension member of the trocar assembly.
Claim 7
Dependent Claim
25 words
A trocar as claimed in claim 5, wherein said extension member is reciprocally mounted to said obturator shaft and is spring-biased away from said obturator.
Claim 8
Dependent Claim
52 words
A trocar as claimed in claim 6, wherein said releasable obturator means maintains said trocar tip in a first extended position in which said extension member is in a spaced relation with respect to said obturator shaft and a second extended position in which said extension member is proximate said obturator shaft.
Claim 9
Dependent Claim
27 words
A trocar as claimed in claim 7, wherein said extension member assumes said second extended position in response to a counterforce being applied to said trocar tip.
Claim 10
Dependent Claim
26 words
A trocar as claimed in claim 7 or 8, wherein said means for releasing said releasable obturator means effects said release from said second extended position.
Claim 11
Dependent Claim
39 words
A trocar as claimed in claim 7, 8 or 9, wherein said means for releasing said releasable obturator means releases said releasable obturator means when said extension member moves away from said proximate position relative to said obturator shaft.
Claim 12
Dependent Claim
28 words
A trocar as claimed in any one of the preceding claims, wherein said trocar assembly further comprises an indicator means which signals the position of said trocar tip.
Claim 13
Dependent Claim
44 words
A trocar as claimed in any one of the preceding claims, wherein said means for releasing the releasable obturator means and said biasing means automatically retract said trocar tip to said retracted position in response to removal of a counterforce from said trocar tip.
Claim 14
Dependent Claim
30 words
A trocar as claimed in any one of the preceding claims, further comprising means for manually effecting retraction of said trocar tip from said extended position to said retracted position.
Claim 15
Dependent Claim
20 words
A trocar as claimed in any one of the preceding claims, wherein said trocar assembly further comprises obturator sleeve means.
Claim 16
Dependent Claim
51 words
A trocar as claimed in claim 14, other than when dependent on claim 2, wherein said ob- sturator sleeve means is lanced or notched to form an internal shelf and said internal shelf is adapted to cooperate with said releasable obturator means to maintain said trocar tip in said extended position.
Claim 17
Dependent Claim
38 words
A trocar as claimed in any one of the preceding claims, and comprising: an outer trocar housing and an inner tro- car housing, said inner trocar housing and outer tro- car housing being reciprocally mounted to each other.
Claim 18
Dependent Claim
46 words
A trocar as claimed in claim 16, wherein said inner trocar housing and outer trocar housing are in spaced relation when said trocar is in said retracted position, and wherein approximation of said inner and outer trocar housings moves said trocar tip into said extended position.
Claim 19
Dependent Claim
28 words
A trocar as claimed in claim 16 or 17, further comprising means for manually effecting retraction of said trocar tip from said extended position to said retracted position.
References Cited (Backward Citations)
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