U.S. patent number 3,661,666 [Application Number 05/061,541] was granted by the patent office on 1972-05-09 for method for making swab applicators.
This patent grant is currently assigned to Philip Morris Incorporated. Invention is credited to Coleman Arthur Foster, David Johnston Taylor.
United States Patent |
3,661,666 |
Foster , et al. |
May 9, 1972 |
METHOD FOR MAKING SWAB APPLICATORS
Abstract
Swab applicators are made by extruding a plastic tube over a
resilient mass of absorbent material. One end of the composite
product is capped in such manner that when the cap is removed a
portion of the absorbent material will be exposed to provide a swab
tip. The applicator is then filled with a medicament or antiseptic
fluid and the other end is sealed.
Inventors: |
Foster; Coleman Arthur
(Richmond, VA), Taylor; David Johnston (Richmond, VA) |
Assignee: |
Philip Morris Incorporated (New
York, NY)
|
Family
ID: |
22036430 |
Appl.
No.: |
05/061,541 |
Filed: |
August 6, 1970 |
Current U.S.
Class: |
156/69; 53/474;
156/244.12; 401/198; 401/199; 604/1; 53/452; 156/180; 401/132 |
Current CPC
Class: |
A47L
25/08 (20130101); B65B 9/24 (20130101); A61M
35/006 (20130101); A61F 13/2082 (20130101) |
Current International
Class: |
A61F
13/20 (20060101); A61F 13/40 (20060101); A47L
25/00 (20060101); A47L 25/08 (20060101); B65B
9/24 (20060101); B65B 9/10 (20060101); B65b
007/00 () |
Field of
Search: |
;128/269
;53/29,36,37,140 ;206/56C ;401/198,202 ;156/69,165,180,244 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Burnett; Robert F.
Assistant Examiner: Epstein; Henry F.
Claims
What is claimed is:
1. Method for making swab applicators which comprises
extruding a continuous length of thermoplastic tubing as a
sheathing over a continuous length resilient mass of absorbent
material, and
drawing said tubing against said absorbent material sufficiently
tightly to radially compress the mass thereof to a certain degree,
such drawing further being effective to reduce the wall thickness
of the tubing sufficiently to render it resiliently deformable,
sectioning the filled tubing into individual applicator lengths
each comprised of coextensive lengths of plastic sheath and
absorbent material,
capping one end of each individual applicator length with a
cup-shaped cap, the applicator length being received only part way
in the cap thereby leaving a void in said cap,
releasably sealing said cap to the outer surface of said sheath in
an encircling course about the latter,
longitudinally bodily displacing the mass of absorbent material
filling said sheath in a direction away from the other end of said
applicator length until a portion thereof fills the void in said
cap and a void of substantially corresponding volume is created in
said applicator length at said other end,
depositing a quantity of liquid product in each applicator length
through said other end, and
thereafter sealing said other end of said applicator length.
2. The method of claim 1 wherein the absorbent material is a tow of
fibrous material.
3. The method of claim 2 wherein said fibrous material is a tow of
cellulose acetate.
4. The method of claim 1 wherein the absorbent material is a
reticulated foam of a synthetic material
5. The method of claim 1 wherein the liquid product is a
medicament.
6. The method of claim 1 wherein the applicator components are
provided in sterile condition and the successive steps in making
the applicator therewith are performed under sterile
conditions.
7. The method of claim 1 wherein said other end of the applicator
length is sealed by inserting a plug therein, said plug being
sealed to said sheath.
8. The method of claim 7 wherein said cap and said plug are joined
to said applicator length with a fluid-tight seal.
9. The method of claim 7 wherein said cap and said plug are of
thermoplastic material and the sealing of said cap and said plug is
effected by heat sealing them to said sheath.
10. The method of claim 7 wherein said cap and said plug are joined
to said sheath with an hermetic seal.
11. The method of claim 1 wherein said other end of the applicator
length is sealed by flattening the sheath to form opposed wall
portions therewith, and heat sealing said opposed wall portions
together.
12. Method for making swab applicators which comprises
extruding a continuous length of thermoplastic tubing as a
sheathing over a continuous length resilient mass of absorbent
material, and
drawing said tubing against said absorbent material sufficiently
tightly to radially compress the mass thereof to a certain degree,
such drawing further being effective to reduce the wall thickness
of the tubing sufficiently to render it resiliently deformable,
sectioning the filled tubing into individual applicator lengths
each comprised of coextensive lengths of plastic sheath and
absorbent material,
weakening said sheath in an encircling course therearound to
provide a cap section in said sheath frangibly joined to the
remainder thereof,
fluid-tightly sealing one end of said applicator length,
depositing a quantity of liquid product in each applicator length
through its other end, and
thereafter fluid-tightly sealing said other end of said applicator
length, said cap section in said sheath being separable from the
rest of said sheath at said frangible section for exposing a length
of said absorbent material as a swab tip.
13. The method of claim 12 wherein the mass of absorbent material
is longitudinally compressed a certain distance inwardly from both
ends of said sheath prior to fluid-tightly sealing said one end of
said applicator length.
14. Method for making swab applicators which comprises
extruding a continuous length of thermoplastic tubing as a
sheathing over a continuous length resilient mass of absorbent
material, and
drawing said tubing against said absorbent material sufficiently
tightly to radially compress the mass thereof to a certain degree,
such drawing further being effective to reduce the wall thickness
of the tubing sufficiently to render it resiliently deformable,
sectioning the filled tubing into individual applicator lengths
each comprised of coextensive lengths of plastic sheath and
absorbent material,
capping one end of each individual applicator length with a
cup-shaped cap,
releasably sealing said cap to the outer surface of said sheath in
an encircling course about the latter and in relation therewith
such as to expose a portion of said absorbent material when said
cap is removed,
depositing a quantity of liquid product in each applicator length
through said other end, and
thereafter sealing said other end of said applicator length.
Description
BACKGROUND OF THE INVENTION
Swab applicators are used for a great number of purposes, such
purposes in many instances being of a single use character. For
such reasons it is desirable that the swab applicators be simply
and inexpensively made. This is particularly true in the case of
surgical swabs where antiseptic considerations preclude more than
one use of such devices. Desirably such swab applicators should
provide for convenience in use, be easily and readily openable,
retain their sterile character if surgical swabs, and offer no
hinderance or hazard to the object with which they are used. Many
types of swab applicator construction are known in the art, but
generally the construction of such devices is more complex than
that which would allow for cheap mass production manufacture
essential for single-use devices. For example, applicator swabs are
known which comprise a glass or plastic tube in which is carried a
swab, a portion of which remains exposed out of the tube, with a
breakable ampoule or vial containing a medicament or other liquid
product which is to be applied being inserted within the swab mass.
The tube is capped at the end opposite the swab and the assembly is
then enclosed in a separate sterile package to protect the exposed
swab portion. Such assembly thus requires a special outer sterile
wrapper and additionally some mode of securing the swab within the
tube, as with adhesives.
SUMMARY OF THE PRESENT INVENTION
The present invention is concerned with a method for the
inexpensive mass production of swab applicators suitable for a wide
range of purposes including antiseptic as well as non-antiseptic
use. In accordance with the present invention a continuous length
of thermoplastic tubing is extruded over a continuous length,
coherent resilient mass of an absorbent material, the composite or
filled article being formed such that the tubing radially
compresses the absorbent material to a certain degree to thereby
hold the mass securely within the tubing. The filled extruded
article is then sectioned into individual applicator lengths and a
cup-shaped cap is inserted over one end of each individual
applicator length, the applicator length being received only part
way in the cap so that a void remains in the latter. Following this
the cap is sealed to the applicator length in an encircling course
around the outer surface of the applicator length to provide at
least a fluid-tight seal of the cap with the latter. The mass of
resilient material filling the applicator length is then displaced
bodily as with a plunger device or other means entering the
uncapped end of the applicator to move the mass so as to fill the
void in the cap but in turn leave a void of substantially
corresponding volume in the applicator length adjacent the open end
thereof. A charge of liquid product such as a medicament,
antiseptic or the like, is then injected into the length through
the open end. The open or other end of the length is then at least
fluid-tightly sealed as with a plug or by deforming and heat
sealing the plastic tubing at said other end. Removal of the
closure cap preliminary to using the swab applicator can be
accomplished by twisting the same relative to he applicator length
to break its seal therewith, and following such removal there is
exposed a length of the absorbent material which serves as the swab
tip during use.
In accordance with the present invention, the absorbent material
can be one of several types suited for the intended purpose
included but not limited to a tow of fibrous material such a rayon,
cotton, cellulose acetate, a natural or synthetic sponge material,
e.g., an open cell reticulated foam material of a synthetic resin,
and the like. The important characteristics of such material, of
course, would be that it would have good absorption quality to hold
the liquid product, would be compressible to a certain degree and
be pervious to liquid flow therethrough.
The character of the fluid-tight seal of the cup-shaped closure cap
to the applicator length of course will depend on the intended use
of the swab. Thus for a surgical swab, the cap desirably should be
completely hermetically sealed to the applicator length.
Additionally, a surgical swab also could be sterilized after final
sealing in known manner employing known sterilizing techniques.
Further economy in the production of the swab applicator provided
by the present invention can be realized by making the swab
applicator as a single component device. In making such embodiment
of the swab applicator, an individual applicator length has the
mass of resilient material filling the length thereof
longitudinally compressed inwardly from both ends thereof, leaving
voids adjacent each end. The tubing or sheath is then flattened at
one end to bring opposed side portions of the end part into contact
and they are heat sealed together to form a fluid-tight seal at
said one end. A charge of liquid product is introduced into the
applicator through the open other end. Such other end is then heat
sealed in the same manner as the first end. A removable cap portion
is then formed in the sheath by providing a frangible or weakened
section in the sheath wall to permit ready separation of the sheath
into two parts and thereby exposing a portion of the length of
compressed absorbent material which can serve as a swab tip.
Other modifications in the construction of the swab applicator and
the method of making the same will of course be possible depending
on the particular use of the swab applicator. For example, various
types of liquid product may be used such as nail polish, shoe
polish, marking inks and the like. Also depending on the use the
amount of swab tip of absorbent material made available for use on
removal of the closure cap can vary, the closure cap length varying
in a corresponding manner.
BRIEF DESCRIPTION OF THE DRAWINGS
A fuller understanding of the nature and objects of the present
invention will be had from the following detailed description taken
in conjunction with the accompanying drawings in which:
FIG. 1 is a longitudinal sectional view of a swab applicator made
in accordance with the principles of the present invention.
FIG. 2 is a sectional view illustrating the condition of the swab
applicator shown in FIG. 1 following removal of the cap therefrom
preliminary to use, the applicator being positioned upright to
facilitate outflow of liquid product through the absorbent
material.
FIG. 3 is a side view, partly in section of a modified form of swab
applicator.
FIG. 4 is a side view of the swab applicator shown in FIG. 3 after
removal of the cap therefrom.
FIG. 5 is a fragmentary sectional view illustrating an alternative
mode of capping the swab tip end of the swab applicator shown in
FIGS. 3 and 4.
FIG. 6 illustrates extrusion apparatus with which a continuous
stock of swab applicator material can be made.
FIG. 7 is a schematic view of the processing steps involved in
making a swab applicator in accordance with the present
invention.
FIG. 8 shown a further form of swab applicator made in accordance
with the principles of the present invention.
FIG. 9 is a longitudinal sectional view of still a further form of
swab applicator made most economically as a single component
device.
Throughout the following description like reference numerals are
used to denote like parts in the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The swab applicator of the present invention is described herein in
representative embodiment form as used for a surgical swab. As will
be indicated at greater length herein, such device desirably is
made under sterile manufacturing conditions involving provision of
sterile components, use of sterile manufacturing machinery and
maintainence of sterile manufacturing environment. If such sterile
manufacturing is not possible, the swab applicators can be
sterilized following the making of the same and employing known
sterilizing procedures for this purpose. It will be understood that
the present invention, however, is not limited to making surgical
swabs only as it is equally applicable for the manufacture of other
types of swab applicators employed normally in conjunction with
application of shoe polish, nail polish, metal polish, cosmetics,
paint, ink, insect repellant and the like. The swab applicator of
the present invention is intended primarily as a one-time use item
being discarded immediately after such first use, and for this
reason it embodies she characteristics of being inexpensive and
easy to make.
FIG. 1 illustrates one form of swab applicator 10 which is
comprised on an easily resiliently deformable thermoplastic tube or
sheath 12 which is filled with a resilient mass of an absorbent,
fluid pervious material filler 14, the filler extending outwardly
from one end of the sheath 12 so as to fill an end closure cap 16
sealed to the sheath as at 18, the cap 16 having any convenient
form such as being cup-shaped. The filler 14 confined within the
sheath 12 is retained therein under a certain degree of radial
compression which condition holds the filler mass within the sheath
without resort to adhesively fixing the former to the latter. The
other end of the swab applicator is closed with a plug 20 which,
similar to the cap 16, is sealed to the sheath as at 22.
Intervening the plug 20 and the mass of absorbent material 14 is a
void 24 extending along a short length of the applicator and
intended to serve as a receiving space for deposit into the
applicator swab immediately prior to fixing plug 20 thereto of a
quantity of liquid product 25. It will be discerned that following
deposit of the product 25 in void 24, some of the liquid will
migrate to the absorbent material 14 and be retained absorpently
therein as shown. The liquid product is thus retained within the
swab available for immediate application when the applicator swab
is opened. The swab applicator is made ready for use by removing
the cap 16 from the sheath 12 which can be accomplished in various
ways including a rotary twisting of the cap while holding the
sheath to break the seal 18. With removal of the cap 16, a
substantial portion of the absorbent material, viz., the portion
extending beyond the end of sheath 12 is exposed to serve as a
swabbing means in the manner illustrated in FIG. 2. By inverting
the applicator to the position shown in FIG. 2, the liquid product
25 flows downwardly into and through the absorbent material and
wets the exposed tip end of the absorbent material for ready
transfer to the object being swabbed as, for example, the skin
areas adjacent a cut or abrasion in human skin which are to be
cleaned with an antiseptic. The resilience of the absorbent
material 14 as well as the thickness and resilience of the sheath
12 provide that the structure of the swab as a whole can be
squeezed to facilitate and accelerate passage of the liquid product
through the absorbent material to the exposed tip end of the
latter.
In making the swab applicator 10, the apparatus and procedures
illustrated in FIGS. 6 and 7 can be employed. With continuing
reference to these FIGURES it will be noted that as a first step a
continuous length stock of absorbent material 14 is fed through a
collecting horn 26 into the center of a crosshead-type extrusion
unit 30 into which is also supplied a flow of molten thermoplastic
material 32. Such extrusion device and method of extruding a filled
plastic tube advantageously may be the same as those described in
pending U.S. Application Ser. No. 747,279 filed July 24, 1968, now
U.S. Pat. No. 3,579,623. As will be noted, the thermoplastic issues
in tacky or plastic state from the extruder unit 30 as a continuous
length of tubing 35 encircling the continuous length of absorbent
material 14. The tubing 35 on exit from unit 30 has a greater
diameter than the final product but it is pulled down to final size
upon entering cooling chamber 40. Such pull down of the plastic
tubing reduces its wall thickness to provide a product which is
squeezably deformable and also results in the tubing effective a
radial compression of a certain degree on the mass of absorbent
material 14. During passage through cooling chamber 40, the
continuous filled article is cooled. Upon exit from the cooling
chamber 40, the cooled composite article is delivered to a cutter
unit 42 (FIG. 7) with which the continuous article is sectioned
into individual swab applicator lengths 12, the individual
applicator lengths 12 then being carried by conveyor 46 to the
forming apparatus shown schematically in FIG. 7 for further
processing in actually assembling the swab applicators 10. At the
first station in the processing line, a cap 16 of suitable
predetermined dimension is placed over the applicator length 12 in
the manner indicated, suitable cap inserting apparatus 50 being
employed for that purpose. As was indicated earlier, applicator
length 12 is received only part way in cap 16 to leave a void in
the cap. Following the insertion of the cap 16 on the applicator
length 12, the cap is sealed to the applicator length 12 in an
encircling, continuous course as at 18 employing for that purpose
suitable sealing means, e.g., a heating iron unit 52. It will be
understood, of course, that other sealing means including adhesive
applicator, sonic fusion, etc. could be used as long as at least a
fluid-tight seal of the cap to the applicator length is achieved.
If the swab applicator is to be a surgical swab unit, a seal of a
hermetic character is preferred. Following the sealing of the cap
16 to the applicator length at one end thereof, it passes on to a
second station at which a piston unit 54 is employed to displace
bodily, the mass of absorbent material 14 from the uncapped or open
end of the applicator length until a portion of the mass fills the
void in the cap 16 and a void of substantially corresponding volume
is created in the applicator length adjacent said open end.
Following withdrawal of the piston unit from applicator length 12,
the applicator length with attached cap is advanced for a further
processing station at which liquid product 25 is introduced into
the applicator length through the open end thereof, such liquid
product being injected or otherwise supplied to the applicator
length with a suitable device such as injector pump 56. At the last
processing station, the open end of the applicator is closed and
provided with at least a fluid-tight seal. To that end, a plug 20
is inserted on the applicator length in the manner shown utilizing
a suitable plug inserting device 58. A heat sealing unit 60 is then
used to seal the plug to the applicator length. During the heat
sealing of the plug 20 and cap 16 to the applicator length 12, the
latter can be rotated about its own axis to facilitate such
sealing.
As shown in FIG. 3 certain modifications in the construction of the
swab applicator are possible. For example, the swab applicator 100
includes a plastic sheath 102 covering an absorbent material mass
104 which is provided as a reticulated foam of a synthetic resin,
the material being a sponge-like mass pervious to liquid flow and
having good characteristics of resilience and softness. The
absorbent material 104 fills the sheath 102 and closure cap 106 in
the same manner as that previously described with respect to the
swab applicator shown in FIG. 1. It will be understood that the
sheath 102 and filler 104 are extruded as a continuous length
composite structure in the same manner as previously described and
shown in FIG. 6. In this construction it will be noted that in lieu
of employing a plug to close off the uncapped end of the swab, the
thermoplastic material of the sheath itself can be flattened so as
to bring opposed side portions of the wall thereof into contact
with each other and then heat seal them together to form the type
of the end seal illustrated at 108 in FIG. 3. To facilitate removal
of the closure cap 106 for exposing a swab tip when using the swab
applicator, the outer surface of the cap 106 may be knurled as at
112 to provide a positive gripping surface for the user when
twisting the cap free from the applicator length. With the removal
of the cap 106, the absorbent reticulated foam material 104 is
exposed as shown in FIG. 4 to provide a swab tip which expands to a
certain degree upon release of the encircling cap structure and the
liquid product 114 can be squeezed through the mass of material 104
and from the void 116 at the opposite end of the swab applicator to
the exposed applicator tip.
FIG. 5 illustrates a modification to the swab applicator of FIGS. 3
and 4 wherein the cap member 120 instead of being provided as a
cup-shaped member could be provided as a short length of tubing and
being sealed at its outer end in the same manner of providing
heat-sealed closure 108 illustrated in FIG. 3.
FIG. 8 shows a further form of swab structure in which in lieu of
an end closure cap member in which is received the applicator
length as shown in FIGS. 1 and 3, the extruded sheath 150 in which
is enclosed the absorbent material 152 is itself modified to
provide a removable cap structure thereon. To provide this the
sheath along an encircling course is provided with a frangible or
weakened section 154 which while strong enough to retain the
absorbent material therein prior to use is insufficient to
withstand moderate rotative twisting of portion 156 with respect to
the remainder of the sheath and such portion 156 thus will tear
loose and be pulled from its enclosing position about a length of
the absorbent material 152. The thus exposed length of absorbent
material constitutes a swab tip. It will be seen then that in
distinction with the earlier-described embodiments, no void is left
in the applicator structure during manufacture thereof and the
liquid product 158 is injected directly into the absorbent material
before sealing off the ends of the swab body with the closure plugs
160.
Most economical and simple manufacture of the swab applicator can
be achieved by making the applicator as a single component device,
i.e., a device comprised of the sectioned, filled tubular article
alone. Such a device 200 is illustrated in FIG. 9 from which it
will be noted the device consists of a tubular sheath 202 enclosing
a mass of absorbent material or filler 204 and constituted of a
length of the extruded, filled article described earlier herein.
The article includes heat-sealed ends as at 206 and 208
respectively, and a pair of voids 210 and 212, with the latter
serving as a reservoir for liquid product 214. The sheath 202 is
provided with a frangible section as at 216 which permits ready
separation of the sheath into two parts to allow exposing a portion
of the filler 204 as at 220 which serves as a swab tip. In making
the swab applicator 200, an individual applicator length of the
tubular filled article has its mass of filler material 204
compressed longitudinally inwardly from both ends to thereby
provide the voids 210, 212. One end 206 is then heat sealed to
provide a fluid-tight seal, such heat sealing being in the same
manner as that shown at 108 in FIG. 3. Liquid product 212 is then
introduced into void 214 and the other end 208 is heat-sealed shut
to provide a fluid-tight seal. A removable cap portion is then
formed on the sheath 202 by providing frangible section 216
therein.
As was indicated earlier if the swab applicator of the present
invention is intended for use as a surgical swab and it is not
manufactured under sterile conditions, the swab applicator after it
has been completely manufactured can be sterilized using known
sterilizing apparatus and techniques. Thus, for example, as shown
in FIG. 1 the swab applicator can be provided with small apertures
indicated at 19 at opposite ends thereof, such apertures passing
through in this case the closure cap 16 and the plastic sheath 12
to provide access and egress for a sterilizing gas or liquid such
as one containing ethylene oxide. Upon completion of the
sterilizing operation the apertures 19 can be sealed in known
manner. Thus, the swab applicator interior is and remains sterile
until used. The mode of exposing the swab tip by twistingly
removing the closure cap 16 ensures avoidance of contamination of
the swab tip.
* * * * *