US5211652A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Scalpel
Assignee: Individual
•
Filing: 1991-10-03
•
Granted: 1993-05-18
•
Expires: 2011-10-03
Abstract
Abstract A retractable blade scalpel comprises a knife blade, a flexible envelope, and an elongated housing forming a blade containment area. When pressure is applied to the flexible envelope the knife blade is longitudinally displaced to a protruding usage position. The knife blade remains outside the housing as long as pressure is applied to the flexible envelope.
Inventors
- 👤 Bruce Derbyshire
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:38
CPC Classifications
A; A61; A61B; A61B17/00; A61B17/32; A61B17/3209; A61B17/3211; A61B17/3213; A61B2017/00535; A61B2017/00539; A61B2017/32113
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
176 words
A retractable blade cutting device comprising; an elongated housing forming a blade containment area and an envelope containment area; a blade reciprocally movable between a withdrawn position within said blade containment area and an extended position protruding exteriorly of said housing; biasing means for exerting a biasing force urging said blade into said withdrawn position; a flexible closed envelope partially enclosed within said envelope containment area, said envelope containing a fluid and having at least one actuator surface accessible from the exterior of said housing; and means to position said blade in the extended position only upon application and maintenance of pressure to said envelope, said means including a piston associated with said blade and engageable by said flexible envelope such that when pressure is applied to said actuator surface, said piston is actuated by said envelope, thereby overcoming the force exerted by said biasing means and causing said blade to shift from said withdrawn position to said extended position, and upon release of said pressure said biasing means returning said blade to said withdrawn position.
Claim 2
Dependent Claim
176 words
A retractable blade cutting device comprising; an elongated housing forming a blade containment area and an envelope containment area; a blade reciprocally movable between a withdrawn position within said blade containment area and an extended position protruding exteriorly of said housing; biasing means for exerting a biasing force urging said blade into said withdrawn position; a flexible closed envelope partially enclosed within said envelope containment area, said envelope containing a fluid and having at least one actuator surface accessible from the exterior of said housing; and means to position said blade in the extended position only upon application and maintenance of pressure to said envelope, said means including a piston associated with said blade and engageable by said flexible envelope such that when pressure is applied to said actuator surface, said piston is actuated by said envelope, thereby overcoming the force exerted by said biasing means and causing said blade to shift from said withdrawn position to said extended position, and upon release of said pressure said biasing means returning said blade to said withdrawn position.
Claim 3
Dependent Claim
17 words
A device as claimed in claim 1, wherein said fluid within said flexible envelope is a liquid.
Claim 4
Dependent Claim
25 words
A device as claimed in claim 1, wherein said flexible envelope includes a pleated portion which extends when pressure is applied to said actuator surface.
Claim 5
Dependent Claim
153 words
A retractable blade cutting device comprising: an elongated housing forming a handle and internally defining a blade containment area; a blade assembly including a blade mounted for reciprocal movement between a retracted position containing within said blade containment area, and an extended position protruding from said blade containment area exteriorly of said housing; biasing means for exerting a biasing force urging said blade into said blade containment area; and a flexible closed envelope containing a fluid and arranged within said housing adjacent to said blade assembly, said envelope having an actuator surface accessible from the exterior of said housing, and means to position said blade in the extended position only upon application and maintenance of pressure to said envelope to overcome the force exerted by said biasing means and urge said blade into said extended position, release of said pressure resulting in said biasing means returning said blade to said blade containment area.
Claim 6
Dependent Claim
153 words
A retractable blade cutting device comprising: an elongated housing forming a handle and internally defining a blade containment area; a blade assembly including a blade mounted for reciprocal movement between a retracted position containing within said blade containment area, and an extended position protruding from said blade containment area exteriorly of said housing; biasing means for exerting a biasing force urging said blade into said blade containment area; and a flexible closed envelope containing a fluid and arranged within said housing adjacent to said blade assembly, said envelope having an actuator surface accessible from the exterior of said housing, and means to position said blade in the extended position only upon application and maintenance of pressure to said envelope to overcome the force exerted by said biasing means and urge said blade into said extended position, release of said pressure resulting in said biasing means returning said blade to said blade containment area.
Claim 7
Dependent Claim
17 words
A device as claimed in claim 4, wherein said fluid within said flexible envelope is a liquid.
Claim 8
Dependent Claim
25 words
A device as claimed in claim 4, wherein said flexible envelope includes a pleated portion which extends when pressure is applied to said actuator surface.
Claim 9
Dependent Claim
29 words
A device as claimed in claim 1, wherein said biasing means further includes resilient means for returning said blade to said blade containment area when said pressure is relieved.
Claim 10
Dependent Claim
29 words
A device as claimed in claim 4, wherein said biasing means further comprises a resilient means for returning said blade to said retracted position when said pressure is relieved.
References Cited (Backward Citations)
US4760848A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-05-17 | 1996-11-16 | 1997-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-17 | 2000-11-16 | 2001-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-17 | 2004-11-16 | 2005-05-18 | $7700.00 | Window Closed / Lapsed |