Note: Descriptions are shown in the official language in which they were submitted.
CA 02357277 2006-02-07
Title: LID FOR MEDICAL WASTE CONTAINER
Field of the Invention
[0001) This invention relates to a lid for a container which receives medical
waste. The container is particularly intended to receive the barrels and
needles of
syringes.
Background of the Invention
[0002] After medical syringes have been used, e.g. to take fluid samples from
patients, or to inject medication into patients, the syringes must be disposed
of. In
some cases the syringe is disposed of as a complete unit, while in other cases
the
needle may be unscrewed from the barrel of the syringe, and the two components
may
be disposed of separately (although in some cases, they are still disposed of
in the
same container). Because of the presence of the sharp needles, this type of
waste is
commonly referred to in the medical profession as "sharps" waste.
[0003] Sharps waste can be hazardous to persons who may come in contact with
such waste, since the needles may be and frequently are contaminated with
dangerous
biological materials. Therefore sharps waste must be disposed of, usually by a
physician or a nurse, in a safe container where it is unlikely to cause injury
while it is
awaiting removal from the physician's office for permanent disposal.
Brief Summary of the Invention
[0004] It is therefore an object of the present invention to provide a lid for
a
container for medical waste, which lid is convenient and relatively safe to
use.
[0005] In one aspect the invention provides a lid for a medical waste
container,
said lid comprising:
(a) a closure pivotally mounted on said lid and movable between a first closed
position and a second open position;
(b) first and second recesses in said lid for receiving said closure when said
closure is in its first and second positions respectively;
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(c) said first recess being closed and serving only to house said closure
when said lid is to be open for depositing said waste;
(d) said second recess having an opening therein to allow waste to be
deposited therethrough into said container;
(e) said closure and said second recess including at least one cooperative
locking mechanism for retaining said closure in said second recess, to
close said opening in said second recess.
(0006] Further objects and advantages of the invention will appear from the
following description, taken together with the accompanying drawings.
Brief Description of the Drawings
(0007] In the drawings:
Fig. 1 is a perspective view of a lid according to the invention, with the lid
spaced above a container;
Fig. 1A is a partial view of a snap fit pivot for the handle of the Fig. 1
lid;
Fig. 2 is a top view of the Fig. 1 container;
Fig. 3 is a top isometric view of the Fig. 1 lid, with the closure in "open"
position;
Fig. 4 is a bottom isometric view of the Fig. 1 lid, with the closure in
temporary
closed position;
Fig. 5 is a bottom isometric view similar to that of Fig. 4 with the closure
in
permanent closed position;
Fig. 6 is a top view of the closure for the Fig. 1 lid, with the permanent
locking
mechanism omitted;
Fig. 7 is a side view of the Fig. 6 closure;
Fig. 8 is an isometric view of the Fig. 6 closure;
Fig. 9A is a top partial view of the Fig. 1 lid, with the closure in "open"
position
and showing section lines for Fig. 9B;
Fig. 9B is a section taken along lines 9B-9B of Fig. 9A;
Fig. 9C is an enlarged view of detail A of Fig. 9B;
Fig. 10A is a top view of the Fig. 1 lid and showing section lines for Fig.
10B;
Fig. 10B is a section taken along lines 10B-10B of Fig. 10A;
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Fig. 10C is an enlarged view of detail A of Fig. 10B;
Fig. 11A is a top view of the Fig. 1 lid with the closure in "closed" position
and
showing section lines for Fig. 11 B;
Fig. 11 B is a section taken along lines 11 B-11 B of Fig. 11A;
Fig. 11 C is an enlarged view of detail A of Fig. 11 B;
Fig. 12A is an exploded isometric view of the closure for the Fig. 1 lid and
showing in particular a portion of the permanent locking mechanism;
Fig. 12B is a top isometric view of the Fig. 12A closure;
Fig. 12C is a bottom isometric view of the Fig. 12A closure;
Fig. 13A is a top view of a button forming part of the permanent locking
mechanism for the Fig. 12A closure;
Fig. 13B is a side view of the Fig. 13A button;
Fig. 13C is a top isometric view of the Fig. 13A button;
Fig. 13D is a bottom isometric view of the Fig. 13A button;
Fig. 14A is a top view of a washer for the permanent locking mechanism for the
Fig. 12A closure;
Fig. 14B is a side view of the Fig. 14A washer;
Fig. 14C is a top isometric view of the Fig. 14A washer;
Fig. 14D is a bottom isometric view of the Fig. 14A washer;
Fig. 15 is a bottom sectional view of the Fig. 1 lid showing the temporary
locking mechanism and showing the permanent locking mechanism in its open
condition;
Fig. 16 is an enlarged view of detail A of Fig. 15 and showing the temporary
locking mechanism; and
Fig. 17 is a top view of an alternative opening design for the Fig. 1 lid.
Detailed Description of the Preferred Embodiment
[0008 Reference is first made to Fig. 1, which shows a medical waste
container 10 bearing a lid 12 having a handle 14. As shown, the lid 12 is of
generally
square configuration (although it can, of course, be round, elliptical or of
other outline),
with an upper surface 15, a lower encircling perimeter wall 16 and an upper
encircling
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' perimeter wall 18 inset slightly from the lower wall 16 and joined to the
lower wall by a
ledge 20. As seen from the inside of the lid 12 (Figs. 4, 15), an extension 22
of the
upper wall 18 extends downwardly inside and parallel to the lower wall 16,
forming a
channel 24 which receives the upper edge 26 of the container 10.
[0009] An outwardly extending ridge 30 encircles the outer wall 32 of the
container 10 and serves as a stop to position the lid 12 accurately on the
container.
Short projections 34 near the top of the container (above ridge 30) protrude
through
openings 36 in the lower lid wall 16 to provide a snap flt when the lid is
placed on the
container, ensuring that the lid 12 will remain in position on the container.
[0010] The handle 14 is hinged to the upper wall 18 by snap-fit stub pivot
shafts
38 (Fig. 1A) which protrude into closed wells 40 in the lid upper surface 15.
The
handle 14 permits a user to lift the container with reduced risk of
encountering a
needle which may have thrust through the wall of the container body. However
the
container body and lid are both preferably formed from a strong material such
as
polypropylene, which is highly resistant to being penetrated by a needle tip.
[0011] The container 10 tapers slightly inwardly in a downward direction, so
that
a number of containers 10 can be nested for storage prior to use. However as
an
added precaution to prevent weakening of the containers when they are nested,
each
container 10 contains two pairs of internal ridges 42 (Fig. 2), one pair at
each of two
opposed corners, extending from the container bottom partway up the inner wall
43 of
the container as shown. Each container also has four slightly protruding
external
pairs of legs 44 at its bottom outer surface, one pair at each corner. When
the
containers 10 are nested, the legs 44 encounter and are stopped by the inner
ridges
42, preventing an inner container from being forced too far into an outer.
container and
thereby weakening the outer container. Instead, during nesting, the containers
stack
with the bottom of one container spaced from the bottom of the container in
which it is
nested.
[0012] The lid 12 includes a closure 46 having an integral flexible strap 48
protruding from one end of the closure. (See also Figs. 6-9) The strap 48 is
pivotally
mounted to the lid upper surface 15 at pivot mounting 50 (which is a
conventional
plastic hinge) so that the closure 46 can move between an open position 54A
(Fig. 3)
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' and a closed position 54B (Fig. 1). In the closure's open position 54A, the
closure 46
is housed in a recess 56 in the lid upper surface 15. The recess 56 includes a
recessed outer portion 58 (Fig. 1 ) shaped to accommodate the closure 46, and
a
further recessed central portion 60 which receives and accommodates the
closure
locking mechanism (to be described), so that the upper surface of the closure
46 is
approximately flush with the lid upper surface 15. An extension 62 of the
recess outer
portion 58 receives a finger tab 64 extending from the closure 46 at the
opposite end
from the strap 48.
[0013] The recess 56 is shaped and dimensioned to accommodate the closure
46 relatively snugly, preferably with enough friction to prevent the closure
from
"flopping" loosely, but with sufficient tolerance to allow a small lifting
force applied by a
finger on the tab 64 to lift the closure 46 from the recess 56, (bending strap
48
upwardly at this time) and then swinging the closure to its.closed position
54B. The
recess extension 62 is sufficiently larger than the finger tab 64 on the
closure to allow
a finger to be inserted under the extension tab 62 to lift the closure for a
movement to
its closed position 54B. The recess 56 is "closed", i.e. it has no openings
from its
upper to its lower surface.
[0014] The lid 12 also contains a second upper recess 68 (Fig. 3), located at
the closed position 54B. Recess 68 has the same shape as the first upper
recess
56, including an extension recess 70 for the finger tab 64. However the second
recess 68, instead of containing a central recess like recess 56, instead
contains an
opening 72 through which syringe needles and barrels and complete syringes may
be deposited into the waste container 10. The opening 72 is of convenient size
for
this purpose and may for example be between one and two inches wide at its
widest
portion, and between two and three inches long. In a preferred embodiment the
opening 72 was approximately 1.40 inches wide at its widest dimension and was
approximately 2.27 inches long at its longest dimension.
[0015] After a syringe or a needle or a syringe barrel has been deposited in
the
container 10, but when the container 10 is not yet full, it is usually desired
to close the
container temporarily (using the closure 46), until the next deposit. After
the container
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' is full, it is desired to lock the closure 46 permanently in closed
position, so that it
cannot readily be opened from outside the container.
[0016] For this purpose the closure 46 includes two locking mechanisms, one
of which holds the closure temporarily in closed position 54B, and the other
of which
can hold the closure permanently in closed position 54B.
[0017] The temporary locking mechanism (see particularly Figs. 11A, 11 B, 11
C,
16) comprises a post 76 which extends downwardly from the lower surface of the
closure 46, near the finger tab 64, and in a position in which it interferes
slightly with
the edge 78 of the opening 72. The lower surface 80 of the post includes a
short
forwardly projecting tab 82 as best shown in Fig. 10C, so that as the post
lower
surface 80 (which is formed of polypropylene) encounters the edge 78, the post
i s
cammed inwardly allowing the tab 82 at the bottom of the post 76 to snap under
the
edge of the opening 72, thus holding the closure 46 in closed position by this
snap-fit.
To open the closure 46, upward pressure is exerted on the finger tab 64, thus
forcing
the thin post 76 to move inwardly and allowing the closure 46 to be opened for
a new
deposit.
[0018] For more secure temporary locking, and also for permanent locking, of
the closure 46 in closed position 54B, a locking mechanism 86 is provided
(Figs. 4, 5,
12-16). The locking mechanism 86 includes a circular flat button 88 mounted in
a
recess 90 in closure 46 and having a diametrical ridge 92 extending upwardly
from
the upper surface of the button 88. The ridge 92 can be grasped to rotate the
button
88. As shown, the ridge 92 extends diametrically slightly beyond the
circumference of
the button on each side of the button and encounters stop ridges 94, 96 (see
also Fig.
6) formed on the upper surface of the closure recess 90, so that the button 88
can be
rotated only from the position shown in Fig. 1 or 3 (parallel to the
longitudinal axis 98
of the closure 46) clockwise to a position 90 degrees from the position shown
in Fig.
1 or 3 (at which time the ridge 92 again encounters the stop ridges 94, 96 and
is
prevented from further rotation). Small raised projections 100 (Fig. 6) (which
look like
dots) extend upwardly from the bottom upper surface of recess 90 and offer
modest
resistance to rotation of ridge 92 over them, to prevent button 88 from
accidentally
being rotated from its unlocked position towards its locked position.
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(0019) The button 88 is secured, by a protruding snap fit pair of integral
members 104 (Fig. 13) which extend through opening 106 in the closure recess
90,
and through a washer 108. Washer 108 is circular and generally of flat disc
shape
but contains a pair of diametrically opposed protrusions 110 which lie in the
same
plane as the remainder of washer 108. A pair of ribs 112 extend diametrically
along
protrusions 110 to stiffen them.
[0020] The upper surfaces of the protrusions 110 are sloped as indicated in
Fig. 14, to form camming surfaces 114. With the closure 46 in its closed
position
54B, then when the button 88 and washer 108 are rotated clockwise, the
protrusions
110 move underneath the bottom wall 116 bordering the recess 72, temporarily
securely locking the closure 46 in closed position. If the button 88 and
washer 108
are rotated a full 90 degrees from their opened unlocked position, the camming
surfaces 114 of the protrusions 110 ride over wedged shaped camming
projections
120 (Fig. 14) extending from the bottom wall 116 of the recess 90, so that the
projections 110 then snap into a recess formed between camming projections 120
and stops 122 spaced circumferentially from projections 120. (The space
between
projections 120 and stops 122 is slightly greater than the width of
projections 110.) It
is now impossible to rotate the button and washer counterclockwise using ridge
92 at
the top of the closure 46, so the closure 46 is now permanently locked in its
closed
position, and cannot be reopened without destruction of the closure.
(0021) The sealed container 10 can then be removed and autoclaved for
sterilization of its contents, after which the container and its contents can
be destroyed
or otherwise dealt with in conventional fashion.
[0022] If desired, and as shown in Fig. 17, the shape of the opening 72 can be
changed to provide a serrated portion 124. The serrated portion 124 can be
used to
grip a syringe needle while the physician or nurse is holding the syringe
barrel, thus
allowing the barrel to be unscrewed from the needle, after which the needle
will fall
into the container.
[0023) .It will be appreciated that other changes may be made in the container
body and lid as described, and such changes and modifications are intended to
be
included within the scope of the present invention.
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