Note: Descriptions are shown in the official language in which they were submitted.
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TITLE: APPARATUS FOR WASHING MACHINE INCLUDING A DRAIN-
BACK GROOVE
BACKGROUND OF THE INV ENTION
Field Of The Invention
The present invention relates generally to an apparatus for washing clothing
and
other items. More particularly, though not exclusively, the present invention
relates to an
apparatus for washing clothing that includes a drain-back groove to minimize
excess
sudsing during the removal of wash water.
Problems In The Art
Currently, top loading washing machines typically include a perforated basket
which holds the clothes or articles being washed and an agitator to mix the
clothes and
articles in the wash water. At the completion of the wash cycle, the
perforated basket is
rotated at a high RPM to extract the wash water from the perforated basket and
the clothes
and articles therein. Because of the spinning nature of the perforated basket,
the extraction
is known as the spin cycle.
During the spin cycle water flows out of the holes in the perforated basket
and
contacts an outer tub. Due to the speed of the perforated basket during the
spin cycle, the
evacuated water continues to flow in the direction of the spin even after
contacting the wall
of the outer tub. This delays the water's arnval at the base of the tub where
it is eventually
pumped away.
Often, the evacuated wash water lingers in the upper portions of the tub,
eventually
accumulating and re-contacting the spinning perforated basket. When this
occurs, the
result is foam. Eventually, the amount of foam is amplified to the point of
suds-locking the
washing machine, a condition where the drain pump is no longer able to evacute
the suds.
During a suds-locking condition, suds may develop to the point where they
exert an
excessive load on the motor used to drive the spinning basket. To prevent this
problem, it
is desirable direct the evacuated wash water towards the base of the tub as
quickly as
possible. This would minimize water build up and any resultant foaming
conditions.
Prior attempts at directing water's movement in the region between the outer
tub
and the perforated basket have included U.S. Patent No. 5,671,617 which issued
to Park et
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al. on September 30, 1997. However, the Park patent uses a series of collars
on one of the
two interior perforated baskets to recycle water onto the top of the clothes
during the wash
cycle. Wash water is extracted in a conventional manner and no effort is made
to direct the
flow of evacuated water during the spin cycle.
A general objective of the present invention is to provide a washing machine
that
solves the problems found with the prior art.
A further objective of the present invention is to provide a washing machine
that
can affect the flow of water between the perforated basket and the outer tub.
Another objective of the present invention is to provide a washing machine
that
efficiently collects wash water during the spin cycle.
A still further objective of the present invention is to provide a washing
machine
that minimizes excessive sudsing in the region between the perforated basket
and the outer
tub.
BRIEF SUMMARY OF THE INVENTION
The foregoing objects may be achieved by the washing machine of the present
invention. The present invention generally comprises a cabinet in. which a
perforated wash
basket is mounted in a conventional manner. An agitator, drive motor and drive
mechanism are mounted within the cabinet, as is well known, to operate the
washing
machine.
Between the perforated wash basket or interior chamber and the cabinet is a
tub or
outer chamber to collect and contain wash water. The tub has a side wall that
includes one
or more grooves to direct wash water downward toward a collection area during
the spin
cycle. Preferably, the groove includes an under-cut portion that prevents
collected water
from flowing out of the groove.
During the spin cycle, the motor operates to turn the perforated basket at a
high
speed. This causes wash water to be extracted from the clothes or articles in
the perforated
basket. The water flows through the perforations in the basket and out to the
tub wall.
Because the basket and clothes are spinning at a high rate, the water flows
out of the
perforated basket and continues to flow in the direction of the spinning
basket. When the
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water contacts the grooves, the flow is redirected to evacuate the water in a
more efficient
manner thereby minimizing sudsing conditions.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a cross-sectional view of a washing machine.
Figure 2 is a sectional side-view of the interior washing apparatus including
a tub of
the present invention.
Figure 3 is a sectional side-view of the interior washing apparatus including
an
alternative tub of the present invention.
Figure 4 is a top sectional view taken generally along line 2-2 of Figure 2.
Figure 4A is an enlarged view of section A of Figure 4 shown during
operational
conditions.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described as it applies to its preferred
embodiment. It
is not intended that the present invention be limited to the described
embodiment. It is
intended that the invention cover all modifications and alternatives which may
be included
within the spirit and scope of the invention.
Now, refernng to the drawings, Figure 1 illustrates a cross section of a
typical
washing machine 10. The washing machine 10 includes a cabinet 12, a control
panel 14,
an access opening 16 and an associated door (not shown). A reversible drive
motor 18 of
conventional construction is mounted within the lower portion of the cabinet
12.
The motor 18 is preferably secured to a web 20 by one or more brackets 22. The
motor output shaft 24 extends upwardly through a clutch 26 shown schematically
in
Figures 2 & 4. The clutch 26 is adapted to respond to the rotational direction
of the shaft
24 to engage/disengage the hub 28 that is connected to a spherically shaped
basket 30.
The basket 30 includes a plurality of perforations 32 in the spherical shaped
walls
for permitting fluid communication between the interior of the basket 30 and
the tub 34.
Thus, as fluid is introduced into the basket 30, the fluid flows through
perforations 32 and
enters tub 34 also. As is further depicted in FIG. 1, the web 20, drive motor
18 and the
washing assembly are shown suspended from the inside of cabinet 12 by a
conventional
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hung strut suspension system 36 which is of known construction and does not
comprise
part of the instant invention.
The washing assembly also includes one or more agitators 38 that operate in a
manner as described in U.S. Patent No. 6,220,063 to Wunderlich on April 24,
2001.
During the washing action, rotation of shaft 24 causes clutch 26 to
simultaneously
disengage hub 28 from shaft 24 and secure hub 28 against rotation. This
enables shaft 24
to rotate freely within hub 28 to drive the agitators 38 while also preventing
rotation of
basket 30.
After the washing cycle has completed, the motor 18 is reversed, causing a
reverse
rotation of shaft 24. This reverse rotation of shaft 24 causes clutch 26 to
couple the shaft
24 to the hub 28, while simultaneously allowing free rotation of hub 28,
thereby causing
the basket 30 to rotate for the spin cycle. During the spin cycle, the washing
fluid passes
outwardly through perforations 32 and into the tub 34 due to centrifugal
force.
Figure 2 shows the tub 34 of the present invention. The tub 34 includes a
lower
portion 40 and an upper portion 42. The inner wall of the upper portion 42
includes one or
more grooves 44 as is shown in Figure 4. As shown in Figure 2, the groove 44
preferably
runs along the entire upper portion of the tub 34, but may be of any length,
width or depth
as desired.
The groove 44 also preferably runs in a generally vertical direction, though
it may
be angled or even spiral around the inside wall of the tub 34 as shown in
Figure 3.
Preferably, the tub 34 is made of a plastic material and formed through well
known
injection molding techniques. Alternatively, the tub 34 may be formed of
stainless steel,
coated metal, or any other durable material using well-understood techniques.
Using a mold, the groove 44 is easily formed into a variety of shapes and
sizes. The
groove 44 preferably includes a front entry portion 46 and an under-cut
channel portion 48.
The under-cut channel portion 48 preferably extends away from the front entry
portion 46
in the same direction as the direction of spin of the perforated basket 30
during the spin
cycle. In order to prevent undue oscillation during the spin cycle, a
balancing arrangement
of grooves should be used. This means the grooves should be equally spaced
along the
wall of the upper portion 42 of the tub 34.
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As is shown in Figure 4A, during the spin cycle the basket 30 spins to expell
water
from the interior of the basket 30, through the perforations 32, and into the
region between
the basket 30 and the tub 34. Because the basket 30 is spinning at a high rate
of speed, the
water will generally continue to flow in the direction of the spinning basket
30. As the
water flows along the wall of the tub 34, it eventually comes into contact
with the groove
44. The outwardly flowing water enters the groove 44 through the front entry
portion 46.
When the water contacts the under-cut channel portion 48, the outward
rotational flow of
the water is redirected into a downward flow as illustrated in Figures 2 and
3. Eventually,
the water flows into the lower tub portion 40 which terminates in a bottom
wall 50 where it
is collected and removed through a discharge port (not shown).
By redirecting the flow of water, the under-cut portion 48 reduces the amount
of
water spinning around the inside wall of the tub 34. This helps to minimize
sudsing
conditions thereby preventing suds lock from occurring.
While the invention is shown in a washer with a spherical tub and a vertical
spin
axis, it is envisioned that it could be applied to a conventional vertical
axis washer with a
cylindrical tub, a conventional drum-style horizontal axis washer, or a washer
with any
spin-axis angle therebetween.
A general description of the present invention as well as a preferred
embodiment of
the present invention has been set forth above. Those skilled in the art to
which the present
invention pertains will recognize and be able to practice additional
variations in the
methods and systems described which fall within the teachings of this
invention.
Accordingly, all such modifications and additions are deemed to be within the
scope of the
invention which is to be limited only by the claims appended hereto.
