Note: Descriptions are shown in the official language in which they were submitted.
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WET/DRY VACUUM DRAIN SYSTEM
BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
The present invention relates generally to wet/dry vacuum cleaners, and more
specifically, to a drain system for a wet/dry vacuum.
2. DESCRIPTION OF RELATED ART
Vacuum appliances capable of picking up both wet and dry material, commonly
referred to as wet/dry vacuums or wet/dry vacs, are often used in workshops
and other
environments where both wet and dry debris can accumulate. Wet/dry vacs
conventionally consist of a collection canister or drum, usually mounted on a
dolly
having wheels or casters, and a powerhead within which a motor and impeller
assembly
is mounted. The motor and impeller assembly creates a suction within the drum,
such
that debris and/or liquid are drawn into the drum through an air inlet to
which a flexible
hose can be attached. A filter within the drum prevents incoming debris from
escaping
from the drum while allowing filtered air to escape. Any liquid drawn into the
drum is
diffused and accumulates on the bottom of the drum. The drum typically
includes a drain
opening that is stopped by a plug or threaded cap, so that a user can remove
the cap to
drain accumulated liquid from the drum.
During operation of a wet/dry vac, a user will often pull the wet/dry vac by
the
hose to move the wet/dry vac to desired locations. Known wet/dry vacs are
prone to tip
over, for example, as the wet/dry vac is pulled across a door threshold, or
even of the
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vac's own accord as it is being pulled by the hose. This makes many prior-art
wet/dry
vacs difficult to use in typical wet/dry environments, such as workshops,
garages, or
basements, where various items may cause the wet/dry vac to tip as it is being
pulled by
the hose.
Further, draining accumulated liquid from the drum is often problematic in
existing wet/dry vacs. As discussed above, the drum typically is mounted on a
wheeled
dolly by the lower portion of the drum. The drain must therefore be positioned
on the
drum at a location above the lower portion of the drum that is mounted to the
dolly.
Thus, to completely empty accumulated fluid from the drum, the entire wet/dry
vac must
be tipped to allow the fluid to drain.
The present invention addresses shortcomings associated with the prior art.
SUMMARY OF THE INVENTION
In an aspect of the invention, an apparatus and method are provided for a
drain
system for a wet/dry vacuum, including a generally U-shaped dolly having
wheels
1s mounted thereon for rotation and a collection drum having an inside bottom
surface
defining a plane. The collection drum is adapted to be mounted to the dolly.
The system
further includes a drain opening on the collection drum. The drain opening is
positioned
generally opposite the closed end of the U-shaped dolly.
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In another aspect of the invention, the system includes a cap having first and
second ends; the first end is adapted to mate with the drain opening in a
sealed manner.
The drain opening defines an inside lower surface. The inside lower surface is
generally
co-planar with the plane defined by the inside bottom surface of the
collection drum.
s In further aspect of the invention, the second end of the cap is defined as
a
member that protrudes from the collection drum. The protruding member has a
length
sufficient to prevent the collection drum from completely tipping.
In yet another aspect of the invention, the generally U-shaped dolly has first
and
second ends, wherein the first and second ends of the generally U-shaped dolly
have
io sufficient length to prevent the collection drum from completely tipping.
The collection
drum is further adapted to be mounted to the dolly at the closed end of the U-
shaped dolly
such that the first and second ends of the generally U-shaped dolly extend
past the
collection drum.
In a still further aspect of the invention, the plane of the inside bottom
surface of
is the collection drum defines a raised portion.
According to a further aspect of the invention there is provided a drain
system
for a wet/dry vacuum, comprising:
a generally U-shaped dolly having wheels mounted thereon;
a collection drum having an inside bottom surface defining a plane, the
collection
20 drum being removably mounted to the dolly; and
a drain opening defined by the collection drum, the drain opening being
positioned
generally opposite the closed end of the U-shaped dolly, wherein the drain
opening
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defines an inside lower surface, the inside lower surface being generally co-
planar with
the plane defined by the inside bottom surface of the collection drum.
According to a further aspect of the invention there is provided a method of
draining the contents of a wet/dry vacuum, comprising:
mounting a collection drum having an inside bottom surface to a generally U-
shaped
dolly, wherein the inside bottom surface defines a plane;
defining a drain opening on the collection drum generally opposite the closed
end of
the U-shaped dolly, wherein the drain opening defines an inside lower surface,
the
inside lower surface being generally co-planar with the plane defining the
inside bottom
surface of the collection drum;
covering the drain opening with a cap, the cap having first and second ends,
the first
end adapted to mate with the drain opening in a sealed manner; and opening the
cap of
the drain opening.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention will be best appreciated
upon reference to the following detailed description and the accompanying
drawings, in
which:
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Fig. 1 is a perspective view of a wet/dry vac employing a drain system in
accordance with an embodiment of the present invention.
Fig. 2-4 illustrate various views of the wet/dry vac illustrated in Fig. 1.
Fig. 5 illustrates various views of the drum of the wet/dry vac illustrated in
Figs. 1
and 2.
Fig. 6 illustrates perspective and top views of the U-shaped dolly illustrated
in
Fig. 1.
Fig. 6A illustrates a top view of another embodiment of the U-shaped dolly in
accordance with the present invention.
Fig. 7 illustrates the drain opening defined by the drum illustrated in Fig.
1.
Fig. 8 illustrates various views of the drain cap in accordance with an
embodiment
of the invention.
While the invention is susceptible to various modifications and alternative
forms,
specific embodiments thereof have been shown by way of example in the drawings
and
are herein described in detail. It should be understood, however, that the
description
herein of specific embodiments is not intended to limit the invention to the
particular
forms disclosed, but on the contrary, the intention is to cover all
modifications,
equivalents, and alternatives falling within the spirit and scope of the
invention as defined
by the appended claims.
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DETAILED DESCRIPTION OF THE INVENTION
Illustrative embodiments of the invention are described below. In the interest
of
clarity, not all features of an actual implementation are described in this
specification. It
will of course be appreciated that in the development of any such actual
embodiment,
numerous implementation-specific decisions must be made to achieve the
developers'
specific goals, such as compliance with system-related and business-related
constraints,
which will vary from one implementation to another. Moreover, it will be
appreciated
that such a development effort might be complex and time-consuming, but would
nevertheless be a routine undertaking for those of ordinary skill in the art
having the
io benefit of this disclosure.
Turning to the figures, Fig. 1 illustrates a perspective view of a wet/dry vac
10
employing a drain system in accordance with the present invention. As shown in
Fig. 1,
the wet/dry vac 10 comprises a collection drum 12 having a lid 13 and a
powerhead
assembly 14. In the particular embodiment illustrated, the powerhead assembly
14 is
detachable from the lid 13. The collection drum 12 illustrated is generally
oval-shaped,
and both the collection drum 12 and the lid 13 may be made of injection-molded
plastic,
such as polypropylene or the like, in accordance with conventional practice.
In accordance with conventional designs, an air inlet port 15 is defined in
the lid
13 or, alternatively, may be defined in a sidewall of the collection drum 12.
The
powerhead assembly 14 houses a motor and impeller assembly, and has defined
therein
an air exhaust or outlet port 16. The powerhead assembly 14 is operable to
create a
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suction within the collection drum 12, such that debris and/or liquid is drawn
into the
collection drum 12 through a hose (not shown) attached to the inlet port 15.
The collection drum 12 is shown in greater detail in Fig. 5. In one
embodiment,
the drum 12 is non-cylindrical, e.g., oval in shape. Additionally, the drum 12
may have a
tapered width with the broadest width at the top and the narrowest width at
the bottom.
For instance, the longest width of the top portion of the drum may be 21.45
inches while
longest width of the bottom portion may be 18 inches. The drum 12 may also
have a
height of 13.122 inches. Each layer of circumference tends to increase the
rigidity of the
side walls of drum 12, in the same way that similar bends, folds or
corrugations in sheet
io metal products (e.g., automobile body parts) tend to increase those
products' rigidity. This
enhances the structural integrity of drum 12.
The collection drum includes a lower portion 20 that is adapted to be mounted
to a
wheeled dolly 22. The lower portion 20 of the collection drum 12 further
defines a drain
opening 24 therein to allow a user to drain accumulated fluid from the
collection drum
12. The drain opening is illustrated in Fig. 5, and in additional detail in
Fig. 7. The drain
opening 24 includes a lower surface 26 that is generally co-planar with the
bottom inside
surface 28 of the drum 12, so that accumulated liquid may be drained from the
drum 12
without requiring tilting of the drum 12. In one embodiment, the diameter of
the drain
opening 24 is 1.545 inches.
In another embodiment, the bottom inside surface 28 defines a raised portion
29
as shown in Figure 5. The raised portion 29 further enables the accumulated
liquid to be
drained from the drum 12 without requiring tilting of the drum 12. In
accordance with
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the present invention, the raised portion 29 has a convex shape. In yet
another
embodiment, the height of the raised portion 29 at the center of the bottom
inside surface
28 of the drum 12 is 0.34 inches and gradually decreases to zero as the raised
portion 29
reaches the outer edges of the inside bottom surface 28.
The dolly 22 shown in Fig. 1 is configured such that the dolly 22 does not
extend
completely around the circumference of the lower portion 20 of the drum 12. In
the
illustrated embodiment, this is accomplished by providing a generally U-shaped
dolly 22,
as shown in Fig. 6. The open end of the U-shaped dolly 22 is positioned so as
to allow
the illustrated placement of the drain opening 24. Prior art dollies that
extend around the
io entire circumference of a collection drum necessitate positioning the drain
opening higher
than the dolly, thus requiring the drum to be tipped to completely empty the
contents
from the collection drum.
Fig. 6A illustrates another embodiment in which the U-shaped dolly 22 has
first
and second ends 52, 54. These extended ends 52, 54 extend past the collection
drum 12
1s when the lower portion 20 of the drum 12 is mounted at the closed end of
the dolly 22.
As a result, these extended ends 52, 54 of the dolly 22 have sufficient length
to prevent
the wet/dry vac 10 from completely tipping over.
Fig. 8 shows various views of a drain cap 30 in accordance with the present
invention. The drain cap 30 is adapted to mate with the drain opening 24 to
seal the drain
20 opening 24. In the embodiment illustrated, the drain cap 30 includes an
externally
threaded portion 32, and the drain opening 24 includes an internally threaded
portion 32
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adapted such that the drain cap 30 may be threaded onto the drain opening 24
to close the
drain opening 24.
The drain cap 30 further includes a member 36 that protrudes opposite the
threaded portion 34. In addition to providing a grip for installing and
removing the drain
cap 30, the protruding member 36 prevents the wet/dry vac 10 from tipping as
it is being
moved via the dolly 22. This is made possible, at least in part, by the novel
position of
the drain opening 24. Referring to Fig. 4, the drum 12 is positioned within
the dolly 22
such that the front wheels 40 of the dolly 22 are on either side of the drain
opening 24.
The protruding member 36 and the front wheels 40 of the dolly 22 form a
"tipping
io radius" indicated by the dashed line labeled with reference 42. Thus, if
the wet/dry vac
is being pulled by a hose coupled to the inlet port 15 to move the wet/dry vac
10 via
the dolly 22, and the forward progress of the wheels 40 is blocked by an
article on the
floor, such as a door threshold, the wet/dry vac 10 will begin to tip forward.
The tip
forward motion rotates around the center of the front wheels 40. As the
wet/dry vac 10
is begins to tip forward, however, the protruding member 36 will contact the
floor,
preventing the vac 10 from completely tipping, until the wheels on the dolly
22 clear the
obstacle, and the wet/dry vac 10 rights itself. In other words, the protruding
member 36
has a length that is sufficient to prevent the vac 10 from completely tipping
over. In one
embodiment, the protruding member 36 further defines a flat tab. In a still
further
embodiment, the drain cap including the protruding member 36 has a length of
1.58
inches.
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The combination of the lower drain opening 24 position and the protruding
member 36 of the drain system prevent the wet/dry vac from tipping.
Additionally, the
distance from the floor (the bottom of the wheels 40) to the drain opening
position 24 is
determinative in preventing the wet/dry vac 10 from tipping. If the drain
opening 24 is
too high, the drain cap 30 will not act as a stop in time to prevent the
tipping. If the drain
opening 24 is too low, the drain cap 30 will strike the obstacle (cord, door
threshold, etc.)
that caused the vac 10 to tip.
The particular embodiments disclosed above are illustrative only, as the
invention
may be modified and practiced in different but equivalent manners apparent to
those
io skilled in the art having the benefit of the teachings herein. Furthermore,
no limitations
are intended to the details of construction or design herein shown. It is
therefore evident
that the particular embodiments disclosed above might be altered or modified
and all such
variations are considered within the scope and spirit of the invention.
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