Surgical suture abstract
A method of and apparatus for sealing unsealed surgical suture
packages by applying heat and sealing pressure substantially simultaneously
to both the sealed edge and the unsealed edge of an unsealed surgical
suture package, thereby forming a sealed surgical suture package.
Surgical suture claims
What is claimed is:
1. Apparatus for sealing unsealed individual packages of surgical
sutures, said packages being generally rectangular including first
and second sealed ends and a pair of sides with one side being sealed
and the opposite side being unsealed, which comprises:
a loading station adapted to receive individual unsealed packages;
a discharge station adapted to discharge individual sealed packages;
a belt driven in a path to move individual packages between said
loading station and said discharge station;
a sealing station positioned along the path of said belt between
the loading station and the discharge station, said sealing station
comprising:
a first sealing die including a pair of sealing surfaces, said
sealing surfaces of said first sealing die being spaced apart from
each other a distance substantially equal to the distanced between
said seal and unsealed sides;
a second sealing die including a pair of sealing surfaces, said
sealing surfaces of said second sealing die being spaced apart from
each other a distance substantially equal to the distance between
said sealing surfaces of said first sealing die, and said first
and second sealing dies being spaced apart from each other; and,
means for moving said first and second sealing dies into sealing
contact with a package positioned therebetween each time an individual
package enters the sealing station, whereby both the sealed and
unsealed sides of the individual packages are sealed at the same
time regardless of the orientation of said first and second sealed
ends.
2. The apparatus as claimed in claim 1 further comprising means
for heating the sealing surfaces of one of said sealing dies.
3. The apparatus as claimed in claim 1 wherein said loading station
comprises a pair of side walls spaced apart from each other a distance
less than the length and greater than the width of said packages.
4. The apparatus as claimed in claim 1 wherein said belt includes
a plurality of lugs, said lugs being linearly spaced apart on said
belt at a distance substantially equal to the length of said packages.
5. The apparatus as claimed in claim 1 further comprising:
a sealed package receptacle positioned adjacent said discharge
station;
a waste receptacle positioned adjacent said discharge station;
and wherein said discharge station comprises:
means for placing properly sealed packages in said sealed package
receptacle; and,
means for selectively placing sealed packages in said waste receptacle.
6. The apparatus as claimed in claim 5 wherein said discharge
station comprises a ramp positioned to receive packages from said
belt and feed packages into said sealed package receptacle.
7. The apparatus as claimed in claim 6 wherein said means for
placing improperly sealed packages in said waste receptacle comprises
means for moving said ramp out of position to receive packages,
thereby allowing packages to move from said belt into said waste
receptacle.
8. The apparatus as claimed in claim 1 wherein said sealing station
comprises means for aligning the package between the sealing dies.
9. The apparatus as claimed in claim 8 wherein said means for
aligning the package between the sealing dies comprises:
a first alignment bar positioned on one side of said sealing dies;
a second alignment bar positioned on the other side of said sealing
dies; and,
means for moving at least one said alignment bars toward the other
of said alignment bars.
10. The apparatus as claimed in claim 9 wherein:
said first alignment bar is fixedly positioned with respect to
said sealing dies; and,
said second alignment bar is movably positioned with respect to
said sealing dies.
11. The apparatus as claimed in claim 10 comprising means for
moving said second alignment bar toward and away from said first
alignment bar.
12. Apparatus for sealing unsealed packages of surgical sutures,
said individual packages being generally rectangular including first
and second sealed ends and a pair of sides with one side being sealed
and the opposite side being unsealed, which comprises:
a loading station adapted to receive unsealed individual packages
two at a time side by side oriented with either said first or second
end first;
a discharge station adapted to discharge sealed individual packages;
a pair of belts driven in a path to move individual packages side
by side between said loading station and said discharge station;
a sealing station positioned along the path of said belt between
the loading station and the discharge station, said sealing station
comprising:
a fixed sealing die including a pair of spaced apart inner sealing
surfaces and a pair of spaced apart outer sealing surfaces;
a movable sealing die including a pair of spaced apart inner sealing
surfaces and a pair of spaced apart outer sealing surfaces, said
first and second sealing dies being spaced apart from each other;
and,
means for moving said movable sealing die toward said fixed sealing
die, each time an individual package enters said sealing station
whereby both the sealed and unsealed sides of the individual packages
are sealed at the same time regardless of the orientation of said
first and second ends;
and means for aligning said packages between the sealing dies,
said means for aligning said packages comprising:
a first alignment bar positioned between the inner sealing surfaces
of said sealing dies;
a pair of second alignment bars positioned outboard of the outer
sealing surfaces of said sealing dies; and,
means for moving said second alignment bars in toward said first
alignment bar prior to moving said movable sealing die toward said
fixed sealing die.
13. The apparatus as claimed in claim 12 further comprising means
for heating the sealing surfaces of said fixed sealing die.
14. The apparatus as claimed in claim 12 wherein each of said
belts includes a plurality of lugs, said lugs being linearly spaced
apart on each of said belts at a distance substantially equal to
the length of said packages.
15. The apparatus as claimed in claim 12 further comprising:
a sealed package receptacle positioned adjacent said discharge
station;
a waste receptacle positioned adjacent said discharge station;
and wherein said discharge station comprises:
means for placing properly sealed packages in said sealed package
receptacle; and,
means for selectively placing sealed packages in said waste receptacle.
16. The apparatus as claimed in claim 15 wherein said means for
placing properly sealed packages in said sealed package receptacle
comprises a ramp positioned to receive packages from said belt and
feed packages into said sealed package receptacle.
17. The apparatus as claimed in claim 16 wherein said means for
selectively placing sealed packages in said waste receptacle comprises
means for moving said ramp out of position to receive packages,
thereby allowing packages to move from said belt into said waste
receptacle.
18. The apparatus as claimed in claim 12 wherein said movable
sealing die is floatingly mounted with respect to said fixed sealing
die.
19. A method of sealing unsealed surgical suture packages, said
unsealed surgical suture packages including a bottom foil sheet
with a heat sealable coating on its top surface and top foil sheet
with a heat sealable coating on its bottom surface, said unsealed
surgical suture packages being generally rectangular with one sealed
edge and one unsealed edge, which comprises the step of:
aligning said unsealed surgical suture package between said sealing
dies such that each said unsealed edge and said sealed edge is disposed
between opposed sealing surfaces of said sealing dies,
placing an unsealed surgical suture package into a receiving station,
and, conveying said unsealed surgical suture package from said receiving
station to a position between said sealing dies,
conveying a sealed surgical suture package from a position between
said sealing dies to a sealed package receptacle when said surgical
suture package is properly sealed
conveying a sealed surgical suture package from a position between
said sealing dies to a waste receptacle when said surgical suture
package is improperly sealed,
applying heat and sealing pressure substantially simultaneously
to both the sealed edge and the unsealed edge of an unsealed surgical
suture package, thereby forming a sealed surgical suture package.
20. The method as claimed in claim 19 wherein said step of applying
heat and sealing pressure includes the steps of:
placing said unsealed surgical suture package between a first sealing
die and a second sealing die, each of said first and second sealing
dies including pair of spaced apart sealing surfaces; and,
moving said first and second sealing dies toward each other.
21. The method as claimed in claim 19 further comprising the step
of heating the sealing surfaces of one of said sealing dies.
Surgical suture description
FIELD OF THE INVENTION
The present invention relates generally to packaging and more particularly
to a method of and apparatus for sealing unsealed or partially sealed
surgical suture packages.
DESCRIPTION OF THE PRIOR ART
Automatic procedures are employed to package surgical suture products
in a sterile condition for shipment and subsequent use in surgery.
As part of the packaging procedure, needle-suture assemblies are
retained in a packet comprising a plastic tray and a paper lid.
The packet containing the needle-suture assembly is sealed between
two metal foils that comprise a sterile package. The sterile package
has a cavity within which the suture packet resides. A seal is formed
around the cavity by pressing the two foils together using a heated
die mechanism which melts thin polymer coatings on the facing surfaces
of the foils in the area exposed to the heated die.
In the manufacturing operation, a plurality of packets are partially
sealed between the top and bottom foils to form an unsealed package.
The unsealed packages are generally rectangular and they are sealed
at both ends and along one side. The spaces between the packets
are also sealed. The package, with the unsealed or partially sealed
edge, is exposed to a sterilizing agent, such as ethylene oxide
gas, to sterilize the suture packet and the interior of the foil
package. Then, the unsealed edge is sealed and the sealed package
is processed through a blanking machine to cut the package into
individual foil packs. The packaging of surgical suture packages
according to the prior art is described in U.S. Pat. No. 5623810.
A problem area in the process for packaging surgical sutures is
in sealing the unsealed edge of the foil package. The unsealed edge
is sealed by inserting the package between a pair of sealing dies
and moving the sealing dies into sealing contact with the unsealed
edge. The operator must insert the package between the sealing dies
correctly. Occasionally, an operator will insert the sealed edge
of the package between the sealing dies, which results in an open
seal. Additionally, alignment within the sealing dies is critical.
Any misalignment can result in a punctured package or crushed cavity.
Surgical sutures demand the highest quality control and no packaging
defects can be tolerated. Any defective packages must be disposed
of. The manufacture and packaging of surgical sutures is very expensive.
Thus, it is very costly to have to scrap packaged needle-suture
combinations at a late stage in the manufacturing and packaging
process.
SUMMARY OF THE INVENTION
The present invention provides a method of and apparatus for sealing
unsealed surgical suture packages. The unsealed surgical suture
packages include a bottom foil sheet with a heat sealable coating
on its top surface and top foil sheet with a heat sealable coating
on its bottom surface. The unsealed surgical suture packages are
generally rectangular in shape, with one sealed edge and one unsealed
edge. The method includes the step of applying heat and sealing
pressure substantially simultaneously to both the sealed edge and
the unsealed edge of an unsealed surgical suture package, thereby
forming a sealed surgical suture package.
The step of applying heat and sealing pressure includes the step
of placing the unsealed surgical suture package between a first
sealing die and a second sealing die. Each of the first and second
sealing dies includes pair of spaced apart sealing surfaces. The
sealing surfaces of at least one of the sealing dies are heated.
The method moves the first and second sealing dies toward each other
to apply heat and sealing pressure to the edges of the package.
The method conveys properly sealed surgical suture packages from
a position between said sealing dies to a sealed package receptacle.
The method conveys improperly sealed surgical suture package from
a position between said sealing dies to a waste receptacle.
The apparatus of the present invention includes a loading station
adapted to receive unsealed packages and a discharge station adapted
to discharge sealed packages. The apparatus includes a belt driven
in a path to move a package between the loading station and the
discharge station. A sealing station is positioned along the path
of the belt between the loading station and the discharge station.
The sealing station includes a first sealing die, including pair
of spaced apart sealing surfaces, and a second sealing die, also
including a pair of spaced apart sealing surfaces. The first and
second sealing dies are spaced apart from each other and means are
provided for moving the first and second sealing dies toward and
away from each other.
A sealed package receptacle and a waste receptacle are positioned
adjacent the discharge station. The discharge station includes a
ramp positioned to receive packages from the belt and feed packages
the sealed package receptacle. Means are provided for selectively
moving the ramp out of its package receiving position, thereby allowing
packages to move from said belt into the waste receptacle.
Preferably, the apparatus of the present invention is arrange to
seal unsealed packages of surgical sutures two at a time. The loading
station is adapted to receive unsealed packages two at time side
by side. A pair of belts are driven in a path to move a packages
side by side between the loading station and the discharge station.
The sealing station includes a first sealing die, having a pair
of spaced apart inner sealing surfaces and a pair of spaced apart
outer sealing surfaces, and a second sealing die, also having a
pair of spaced apart inner sealing surfaces and a pair of spaced
apart outer sealing surfaces.
The sealing station includes alignment means for aligning the packages
between the sealing dies. The alignment means includes a first alignment
bar positioned between the inner sealing surfaces of the sealing
dies and a pair of second alignment bars positioned outboard of
the outer sealing surfaces of the sealing dies. The second alignment
bars are movable in and out, toward and away from, the first alignment
bar.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the preferred embodiment of the apparatus
of the present invention.
FIG. 2 is top view of the preferred embodiment of the apparatus
of the present invention.
FIG. 3 is a sectional view taken generally along line 3--3 of FIG.
1 showing details of a sealing station according to the present
invention.
FIG. 4 is a perspective view of an unsealed surgical suture package.
FIG. 5 is a perspective view of a sealed surgical suture package.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, the preferred embodiment of the
apparatus of the present invention is illustrated in FIGS. 1-3.
The apparatus of the present invention is adapted to seal surgical
suture package, such as those illustrated in FIGS. 4 and 5.
Referring to FIGS. 4 and 5 a surgical suture package is designated
generally by the numeral 11. Package 11 is formed of a top foil
sheet 12 and a bottom foil sheet 14 each being coated with a heat
sealable material. Package 11 is generally rectangular in shape,
and it includes sealed ends 13 and 15 and a sealed side edge 17.
Suture packets are contained in cavities 18 formed in one of the
foil sheets comprising package 11. The foil sheets are sealed together
in the areas around cavities 18.
In the unsealed condition, as illustrated in FIG. 4 the side 19
opposite side 17 is unsealed to enable sterilizing gas to enter
the interior of package 11 through a plurality of vents 20. In the
sealed condition, as illustrated in FIG. 5 side 19 is sealed by
the method and apparatus of the present invention. After side 19
is sealed, package 11 is passed to a blanking machine, where individual
packs are cut out of package 11.
Referring now to FIGS. 1 and 2 the apparatus of the present invention
is designated generally by the numeral 31. Apparatus 31 includes
a loading station, designated generally by the numeral 33 adapted
to receive unsealed packages, and a discharge station, designated
generally by the numeral 35 adapted to receive sealed packages.
A pair of parallel endless belts 37 and 38 are trained for rotation
on rollers 39 and 41 to convey packages 11 between loading station
33 and discharge station 35. Belt 37 is driven by means of a motor
43 and a suitable transmission, partially shown in phantom in FIG.
1. A sealing station, designated generally by the numeral 45 is
disposed along the path of belt 37 between loading station 33 and
discharge station 35. Apparatus 31 is preferably supported by a
table-like structure in a sterile cleanroom environment.
Referring particularly to FIG. 2 loading station 33 includes a
pair of spaced apart side walls 47 and 49 and a center wall 51.
Side walls 47 and 49 are spaced apart from center wall 59 a distance
greater than the width, but less than the length, of a package 11.
Side walls 47 and 49 and center wall 51 together with belts 37
and 38 form a pair of loading trays into which an operator may
load packages 11 side by side two at a time. As shown in FIGS. 1
and 2 belt 37 includes a plurality of lugs 53 spaced linearly along
each belt at a distance substantially equal to the length of a package
11.
As best shown in FIG. 1 discharge station 35 includes a ramp 55
pivotly mounted adjacent roller 41. Ramp 55 is moveable by means
of a pneumatic cylinder 57 between a first position and a second
position, which is shown in phantom in FIG. 1. In the first position,
packages 11 slide along ramp 55 from belt 37 into a sealed needle
receptacle 59. In the second position, packages 11 fall from the
end of belt 37 into a waste receptacle 61. As will described in
detail hereinafter, pneumatic actuator 57 is operated to move ramp
55 from the first position to the second position when logic in
a controller (not shown) indicates that a package 11 may not be
sealed properly.
Referring now to FIG. 3 there is shown details of sealing station
45. Sealing station 45 includes a fixed upper plate 63 and a fixed
lower plate 65. Upper plate 63 supports a sealing die that includes
an inner member 67 having a pair of spaced apart inner sealing
surfaces, and a pair of spaced apart outer sealing members 73 and
75 each having a sealing surface. Each of sealing members 67 73
and 75 include a temperature controlled heating element, as for
example heating element 81 of outer sealing member 77 that is adapted
to heat each sealing member to a maximum temperature of about 220.degree.
C., with a preferred temperature about 175.degree. C. The preferred
temperature is determined according to the packaging material. Suitable
sensors, such as thermocouples (not shown) are provided for monitoring
and controlling the temperature of the heated sealing members. Insulating
members 83 85 and 87 are mounted between upper plates 63 and heated
sealing members 67 73 and 75 respectively.
A moveable assembly designated generally by the numeral 89 is positioned
between upper plate 63 and lower plate 65 to form a lower sealing
die. Assembly 89 includes an inner sealing member 91 having a pair
of spaced apart elastomeric inner sealing surfaces, and a pair of
outer sealing members 93 and 95 each having an elastomeric sealing
surface.
Assembly 89 is moveable up and down by means of a pneumatic actuator
101 (shown in FIG. 1) that includes an actuator rod 103. As shown
in FIG. 3 actuator rod 103 is pivotly mounted to allow assembly
89 to float so as to allow the lower sealing surfaces to seal properly
against the upper sealing surfaces. Assembly 89 is stabilized by
means of guide rods 105 and 107 that move through bushings 109 and
111 respectively in lower plate 65.
Packages 11 are carried into and out of sealing station 45 by means
of belts 37 and 38 which are carried in ways in assembly 89. As
shown in FIG. 3 a pair of packages are supported side by side within
sealing station 45 with the edges of the packages supported by the
sealing surfaces of sealing members 91 93 and 95. The packages
are aligned within sealing station 45 by means of an alignment system,
that includes a pair of moveable alignment bars 113 and 115 supported
by upper plate 63 on opposite sides of assembly 89. Alignment bars
113 and 115 are moveable in and out with respect to assembly 89
by means of pneumatic actuators 117 and 119 respectively. A central
alignment bar 121 is supported between the sealing surfaces of central
sealing member 67. Central sealing member 91 of assembly 89 has
a longitudinal extending slot 92 adapted to receive central alignment
bar 121 as assembly 89 moves upwardly. Actuation of pneumatic actuators
117 and 119 urge alignment bars 113 and 115 inwardly thereby to
force packages 11 into engagement with central alignment bar 121.
Thus, packages 11 are properly aligned with the sealing surfaces
as assembly 89 moves upwardly.
Spring biased plates 121 and 123 are positioned between upper plate
63 and assembly 89. As assembly 89 moves upwardly, plates 121 and
123 engage packages 11 to hold them in place between the upper and
lower sealing dies.
In operation, an operator places a pair of unsealed packages 11
side by side in receiving station 33. With the packages properly
in place, the operator actuates a switch or the like, to cause motor
43 to index belts 37 and 38 one position toward sealing station
45. When belts 37 and 38 stop, a controller (not shown) actuates
pneumatic cylinder 101 to urge assembly 89 of sealing station 45
upwardly to apply sealing pressure and heat to both the sealed and
unsealed edges of the packages. Since the apparatus and method of
the present invention apply heat and sealing pressure substantially
simultaneously to both edges of the package, it does not matter
how the operator inserts the packages into receiving station 33.
Again, the heated sealing dies are maintained at a temperature of
about 175.degree. C. The controller (not shown) maintains the dies
in a closed position under a pressure of 60.+-.5 p.s.i. for about
1.5 seconds. Then, the dies are opened by retracting actuator 101.
If the controller detects that any of the sealing time, pressure,
or temperature values are out of range, the controller actuates
pneumatic cylinder 57 at an appropriate time to cause the packages
sealed under improper conditions to fall into waste receptacle 61.
From the foregoing, it may be seen that the method and apparatus
of the present invention are well adapted to overcome the shortcomings
of the prior art. By substantially simultaneously sealing both the
sealed and unsealed edges, the opportunity for operator error is
virtually eliminated. The present invention results in increased
yield of high quality packages.
Although a preferred embodiment of the invention has been described
herein with reference to the accompanying drawings, those skilled
in the art will appreciate that various alternatives and modifications
thereof are within the scope and spirit of the invention as set
forth in the appended claims. |