Note: Descriptions are shown in the official language in which they were submitted.
BACKGROUND OF THE INVENTION
A self-contained disposable swab is a useful device, par-
ticularly for medical applications. Prior to such self-contained
devices, the various swabbing solutions, such as germicidal soap,
detergents, and medications were stored in capped bottles contain-
ing much more solution than would normally be necessary for a sin-
gle use. Dry absorbent swabs, such as the common cotton swab on a
wood stick were kept in separate boxes. The user normally selected
one such swab and dipped it into the swabbing solution appropriate
for the task. There were several inconveniences associated with
this older method. The primary inconvenience was the necessity of
carrying along relatively large bottles of the various solutions
in doctors bags or first-aid kits. Additionally, where the swab
would be placed in contact with contaminants or bacteria, the swab
could not be re-dipped into the bottle to get more solution. In-
stead, a new swab had to be used each time it was necessary to wet
the swab tip.
Self-contained swab units have proven to be a convenient
solution to the above-mentioned problems. Each unit carries an
amount of solution judged to be approximately right for one usage.
The solution is sealed away from the swab when not in use so that
the unit may be stored and carried in a doctors bag or in a techni-
cians portable kit until it is needed. The unit, exclusive of the
solution, is relatively inexpensive and thus is suitable for dispos-
able use.
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However r it would be desirable to provide an improved means of main-
taining a rupturable seal between the swab and the liquid. Ideally,
such a seal would be airtight and watertight even when the unit is
subjected to minor blows, such as would occur in a doctors bag or
technician's kit, and when placed under a modest weight such as
other medical instruments being stored upon it. Yet the seal
should be easily openable when the swab is to be used. Addition-
ally, it would be an advantageous feature if the seal would be
partially closeable on demand so that the flow of liquid to the
swab could be regulated.
Since the units are intended to be disposable, the
cost factor is important. A seal that meets the operational
requirements of the previous paragraph must also be capable of
being installed in the unit inexpensively. This will almost
invariably necessitate that the seal be installed by a simple
automated process.
SUMMARY OF THE INVENTION
A disposable swab unit comprises a generally hollow
cylinder having a closed end and an open end capped by a structure.
The swabbing structure providing a swabbing means. A liquid medium
is provided in the hollow cylinder. A plug having a conical face
and a base portion slightly larger than the bore diameter of the
cylinder is inserted within the bore of the cylinder to form a sealed
chamber in the portion of the cylinder between the closed end and
the plug for containing the liquid medium.
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BRIEF DESCRIPTION OF THE DRAWINGS
For the purpose of illustrating the invention, there is
shown in the drawings a form which is presently Preferred; it being
understood, however, that this invention is not limited to the pre-
cise arrangements and instrumentalities shown.
BRIEF DESCRIPTION OF THE DRAWING
Figure 1 is a longitudinal section view of a swab unit ac-
cording to the present invention;
Figure 2 is a side view of the plug;
Figure 3 is a bottom view of the plug.
DETAILED DESCRIPTION OF THE DISCLOSURE
~ eferring to the drawings in detail wherein like numerals
indicate like elements, the present invention is embodied in a dis-
posable self-contalned swab unit designated generally as 10. The
unit 10 includes a cylindrical plastic tube 12 closed at one end
14 and open at the other end 16. Tube 12 is preferably made of
plastic such as polyprophylene or a copolymer blend selected to
preserve the integrity of the seal chamber.
A foam rubber cube 18 caps the open end of tube 16.
` Cube 18 is herein shown as a foam rubber cube, but it will be
understood that any suitable absorbent material may be used and
~j any convenient geometric configuration may be employed, as the
function of cube 18 is to absorb the swabbing solution and apply
it to the area being swabbed. Cube 18 is attached to tube 12 by
a suitable glue or adhesive.
A liquid solùtion 20 is loaded to a pre-determined amount
~ in tube 12. The solution can be a liquid detergent, a germicidal
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soap, a medication or any of a variety of other liquids normally
applied with a swab. When tube 12 is constructed of a transparent
plastic, the liquid will be visible through the walls of tube 12.
It may therefore be advantageous to use appropriate dyes to color
code the various liquids in different swab units so that ready
identification is available. Also, printing may be applied to
the tube to identify the contents of the tube and/or instructions
for use.
The liquid 20 is sealed away from cube 18 by plug 22.
Plug 22 may be best viewed in Figure 2. Plug 22 is generally con-
ical, having a base portion 24 and a cone portion 26. The base por-
tion 24 has a cylindrical surface defined along its outside diameter
that will be referred to as the sides 28 of the base 24. A generally
flat surface 30 is provided by the bottom of the base 24. Surface 30
contains a centering depression 32~ shown as a rectangular depression
in these drawings, so that a centering tool may be used to place the
plug 22 within the tube. The plug 22 is preferably a plastic mater-
ial integrally formed by injection molding.
The outside diameter of base 24 is slightly larger than the
inside diameter of tube 12. When plug 22 is inserted into tube 12
and properly centered, the generally flat surface 30 is perpendicular
to the wall of tube 12. Tube 12 is preferably composed of a sufficient-
ly pliable material such as polyprophylene or a copolymer blend. In
this manner, the wall of tube 12 will bulge outwardly as shown at 34
to accomodate the sides 28, thus causing a sealed cavity 36 in tube
12 which will serve as a reservoir for the liguid 20.
In construction and assembly of the device, tube 12 is loaded
to a pre-determined amount with liquid 20. Plug 22 is then inserted
into the open end 16 of tube 12, with the conical face 26 of plug 22
entering open end 16 first. A centering tool (not shown) is used in
cooperation with centering depression 32 to position and center plug
22 in tube 12. A suitable glue or adhesive is then applied either to
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the cavity in cube 18 or to the upper extremity of tube 12, and cube
18 is seated as a cap over tube 12. The glue, or adhesive, when dry,
holds cube 18 in place.
The swabbing unit 10 is then ready for storage. In this
position, the liguid 20 is sealed against contamination or evaporation.
The foam rubber cube 18 is dry. The unit 10 can be stored in any posi-
tion without having the liquid 20 saturate cube 18. The unit 10 can
even withstand moderate jolts and weights without having the seal
ruptured.
Immediately prior to use, the unit 10 is inverted so that
cube 18 points downward, and tube 12 is squeezed between the thumb
and forefinger. The pressure of fluid 20 on conical face 26 causes
plug 22 to pivot relative to the walls of tube 12. Liquid 20 then
flows past plug 22 and saturates cube 18. When the user releases
the squeezing pressure on tube 12, suction in tube 12 will pivot
plug 22 back towards its sealing position. While the force of the
suction will not be great enough to completely center and align
plug 22 to its original position, it will cause sides 28 to contact
the inside walls of tube 12, thus effecting a partial seal. This
allows the user to control the rate at which he uses fluid 20.
It can thus be seen that the objects of the invention have
been accomplished, i.e., providing a self-contained swab unit having
an improved seal at a reasonable cost.
The present invention may be embodied in other specific
forms without departing from the spirit or essential attributes
thereof and, accordingly, reference should be made to the appended
claims, rather than to the foregoing specification, as indicating
the scope of the invention.
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