Plastic and nonmetallic article shaping or treating: processes – With severing – removing material from preform mechanically,...
Reexamination Certificate
1999-09-03
2001-11-20
Tentoni, Leo B. (Department: 1732)
Plastic and nonmetallic article shaping or treating: processes
With severing, removing material from preform mechanically,...
Reexamination Certificate
active
06319445
ABSTRACT:
FIELD OF THE INVENTION
The present invention is directed to systems for processing strings and yarns. Mowe particularly, the present invention is directed to automated systems for thermally forming and cutting surgical sutures.
BACKGROUND OF THE INVENTION
Various automated systems for forming and cutting surgical suture tips exist or are known in the art. In one such machine, means for simultaneously advancing in parallel at least six separate strands of suture material, and six independent tensioners for maintaining respective parallel portions of each of the six strands at a preset tension are provided. Once a predetermined length of suture material had been advanced by the advancing means, a horizontal heater bar (positioned perpendicular to the six suture strands) is actuated by an electronically controlled solenoid which moves a planar heater bar into contact with one side of the suture strands for a predetermined dwell time. Once the predetermined dwell time has elapsed, the solenoid retracts the heater bar to its original position, and the heat exposed (or heat-stiffened) section of suture material is advanced to a cutting station. At the cutting station, the heat-stiffened section of suture material is cut at its midpoint, thereby producing a suture with two stiffened ends. Other mechanisms for forming and cutting surgical suture tips are shown in U.S. Pat. Nos. 4,832,025, 4,806,737 and 5,226,336 to Coates. The system described in the Coates patents uses convective or non-contact heating to form suture tips.
Known systems for forming and cutting surgical suture tips suffer from two primary drawbacks. First, such systems typically produce a suture tip which lacks a substantially uniform cross-section. Second, such systems typically cut the suture tip in an imprecise manner, thereby leaving a cut end which may be irregular or distorted in shape. From a manufacturing standpoint, suture tips having non-uniform cross-sections and/or irregular or distorted cut ends are undesirable because, among other things, such sutures are difficult to insert into needles.
It is therefore an object of the present invention to provide a surgical suture having a tip with a substantially uniform cross-section and a precisely cut end which may be easily inserted into a needle.
It is a further object of the present invention to an automated system and method for manufacturing surgical sutures having tips with substantially uniform cross-sections.
It is a still further object of the present invention to provide an automated system and method for making surgical sutures with tips having precisely cut ends.
These and other objects and advantages of the invention will become more fully apparent from the description and claims which follow or may be learned by the practice of the invention.
SUMMARY OF THE INVENTION
The present invention is directed to a combined apparatus for heating and cutting a suture tip formed from a length of unfinished surgical suture material. First and second heating dies are provided for heating the length of unfinished surgical suture material to form the suture tip, and first and second cutting dies are provided for cutting the suture tip, At least one heating die mechanical actuator is provided for moving the first heating die between a retracted and an extended position and for moving the second heating die between a retracted and an extended position, the first and second heating dies occupying a combined heating and cutting space adjacent to the unfinished surgical suture material only when the first and second cutting dies are in their retracted positions. At least one cutting die mechanical actuator is provided for moving the first cutting die between its retracted and an extended position and for moving the second cutting die between its retracted and an extended position, the first and second cutting dies occupying the combined heating and cutting space only when the first and second heating dies are in their retracted positions.
In accordance with a still further aspect, the present invention is directed to a method for heating and cutting a suture tip formed from a length of unfinished surgical suture material. The length of unfinished surgical suture material is first positioned at a combined heating and cutting location between a first face of a first heating die and a second face of a second heating die. Next, the first heating die is moved from a retracted to an extended position and the second heating die is moved from a retracted position to an extended position, the first face of the first heating die being against the second face of the second heating die when the first heating die is in its extended position and the second heating die is in its extended position. Next, a length of suture tip material positioned at the combined heating and cutting location is exposed by moving the first heating die from its extended to its retracted position and by moving the second heating die from its extended to its retracted position. While the length of suture tip material is positioned at the combined heating and cutting location, a cutting blade is moved across a cross-section of the length of suture tip material. In a preferred embodiment, first and second cutting dies are placed in a closed position when the cutting blade is moved across the cross-section of the length of suture tip material.
REFERENCES:
patent: 284496 (1883-09-01), Seymour
patent: 1651834 (1927-12-01), Novick
patent: 2236833 (1941-04-01), Pell et al.
patent: 2997905 (1961-08-01), Larson
patent: 3472108 (1969-10-01), Vandersip
patent: 3926194 (1975-12-01), Greenberg
patent: 4017012 (1977-04-01), Brock
patent: 4048833 (1977-09-01), Lorenz
patent: 4075046 (1978-02-01), MacDonald
patent: 4605115 (1986-08-01), Genans
patent: 4694718 (1987-09-01), Kinsley
patent: 4922904 (1990-05-01), Uetake et al.
patent: 5080667 (1992-01-01), Chen et al.
patent: 5156788 (1992-10-01), Chesterfield et al.
patent: 5349890 (1994-09-01), Butkus et al.
patent: 5452636 (1995-09-01), Rattan
patent: 5485668 (1996-01-01), Demarest et al.
patent: 5540778 (1996-07-01), Colligan et al.
patent: 6128816 (2000-10-01), Demarest et al.
patent: 2 632 850 (1989-12-01), None
Haase Bernd
Smith Kenneth J.
Ethicon Inc.
Tentoni Leo B.
LandOfFree
Process for heating and cutting a surgical suture tip does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for heating and cutting a surgical suture tip, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for heating and cutting a surgical suture tip will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2593006