Note: Descriptions are shown in the official language in which they were submitted.
WASHING MACHINE TUB CONSTRUCTION
This is a division of commonly assigned Canadian
Patent Application Serial No. 465,669 filed October 17, 1984
BACKGROUND OF THE INVENTION
This invention relates generally to clothes
washing machines, and more particularly to clothes wash-
in machines of the top loading type having a resiliently
mounted, non-rotary outer tub and an internal spin tub
rotating about a vertical axis.
Clothes washing machines of the top loading type
have a cabinet comprising a base, your sidewall portions,
and a top having therein a lid Jo allow access into the
spin tub, which usually has an agitator mounted on the
axis and which, in turn, is rotatable mounted within an
outer tub. Generally, the spin basket is perorate to
allow water removal during centrifugal extraction, while
the outer tub is imper~orate and serves to contain the
liquid washing medium. The outer tub has a mounting
assembly which includes a transmission, drive motor, and
pump, and is resiliently mounted to absorb vibration from
unbalanced loads that occur particularly during the act
coloration and high speed during the spin or centrifuging
portion of the cycle. While many arrangements are pro-
voided for mounting the tub, transmission, and other come
pennants, a common arrangement it to have them mounted on
a dome-type assembly on the base and anchored by springs
extending between the tub mounting assembly and the base
to hold the entire outer tub and related assemblies in a
centered position with regard to the sidewalls of the
cabinet and the top opening. Generally, the outer tub is
made as small as possible to provide a minimum clearance
around the spin tub, so as to minimize the amount ox
I
.
water used in a wash cycle. Of course, it is possible to
select various fill levels for water during the portions
of the cycle.
Of particular concern with machines of this type
is the necessity for avoiding excessive movement of the
outer tub and mounting assembly because of unbalanced
loads of clothes in the spin tub during the spin opera-
lion, and particularly during the acceleration phase of
the spin tub when, depending upon the amount and location
of the load, it is possible to encounter resonant ire-
quenches which could result in excessive excursions of
movement, causing the outer tub to strike the walls ox
the cabinet. While such excessive excursions can be pro-
vented by using an unbalance switch which detects such
excessive movements of the tub and de-energizes the drive
motor, so that the clothes can be physically rearranged
to correct the unbalance, it is desirable to tolerate
certain excursions during the spin-up portion of the
cycle, since such excursions in the movement of the tub
may substantially decrease once the full spin speed is
reached
In order to minimize the magnitude of the excur-
sons of the tub, it is possible to increase the force of
the centering springs, but if these are made too stiff,
other problems may be encountered as a result of the come
pled dynamics of the rotating system. However, generally
two other approaches are used, both of which involve in-
creasing the mass of the suspended tub assembly so as to
thereby decrease the effects of unbalanced loads. One
such approach is simply to increase the weight ox the
outer tub assembly, preferably at a point as high above
the base as possible. This can be done by adding weights
to the exterior of the tub, as disclosed in US. Letters
Patent No. 3,47S,928. Another approach has been to use a
weight ring at the top of the spin basket, as shown in T.
R. Smith patent No. 2,926,136, which has an additional
gyroscopic stabilizing effect during spin because of the
rotation of the mass.
While the first of these solutions has the ad-
vantages of being relatively simple and low cost in menu-
lecture, it does require substantially heavier weights
than the rotating rung and these weights add to shipping
costs and make the unit more difficult to move if nieces-
spry for service. Furthermore, such weights function
only when attached to the outer tub, and when such tub is
made of a heavy steel construction, no problem is pro-
sensed. However, it the outer tub is made of a plastic
material, to decrease the weight and increase the Corey-
soon resistance of the unit, such material is not stiff
enough to support the weights in their normal position.
On the other hand, while a rotating annular ring
of weighted material at the top of the spin tub does not
require nearly the mass of the stationary weights, it
does require a much more complex and precise construction
for the spin tub to avoid any unbalance caused by non-
uniformity ox the balance ring itself. Heretofore, such
balance rings have usually been built into the spin tub
structure itself, using several walls and an inwardly
projecting structure which is difficult to form with a
high degree of accuracy, since such tubs are usually made
of a porcelain enameled steel, which is easily distorted
under the high temperatures required for the porcelain
enameling operation. For this reason, the use of a heavy
weight ring built into the top of the spin tub has
resulted in an increased cost of manufacture over the
external weight arrangement.
Another problem presented by such top loading
washing machines is the necessity to control the clothes
37~
within the spin tub and prevent their escape therefrom.
For example, if small articles of clothing come out of
the spin tub and enter the space between the spin tub and
the outer tub, it is almost impossible to remove them
without disassembling the machine, and they can reach
locations where they can cause substantial damage upon
continued operation of the machine. For this reason, it
is a usual construction to provide a clothes Gordon the
form of an annular piece that mounts at the top on the
inside of the spin tub and extends toward thy central
axis so that small clothing articles are retained within
the spin tub.
Likewise, to ensure that space between the spin
tub and the outer tub is not readily accessible, an
annular cover is used over the outer tub extending radix
ally inward o'er the clothes guard on the spin tub, and
generally provides a configuration to define an opening
which corresponds with the opening through the top ox the
cabinet to prevent the possibility that during the fill-
in or removal of clothes any such clothes can pass out-
warmly above the outer tub and fall down into the motion-
is within the cabinet. Such tub cover generally also
functions to mount such items as bleach dispensers and
lint filters, and generally provides the mount for the
Jill nozzle by which the tub is f tiled during the wash
and rinse cycles. the fill nozzle mounted in the tub
cover generally is intended to spray downwardly on the
clothes which may be adhering to the sides of the spin
tub, as is particularly desirable in the case of a spray
rinse after the first centrifugal extraction cycle ox the
washing medium, but since the machine is generally not
rotating during other f ill cycles, this results in a con-
cent ration of the incoming water at a particular spot.
To overcome this, it has been proposed that the ~111
~2~37~
5 --
system use a tube extending around the bottom side of the
tub cover inwardly of any projection of the spin tub or
clothes guard and having openings to spray downwardly on
the clothes. Such an arrangement is shown in US. Letters
Patent No. 3,663,975, in which a rubber tube is mounted on
the underside and has a plurality of slots so that the
spray water is distributed over the entire periphery of the
spin basket and the clothes therein, even when the basket
is not rotating during a fill operation. However, such a
construction has required the use of a rubber tube for
mounting purposes, and the openings in such tube can easily
be distorted with wear and age, and have little control
over the radial direction of spray during a fill or rinse
cycle.
SUMMARY OF THE INVENTION
The present invention relates to the structure of
the outer tube and spin tub of a top loading washing ma-
chine having a gyroscopic type of suspension.
According to one aspect of the present invention,
as defined in the aforementioned parent application, stab-
lily of the gyroscopically mounted structure is enhanced
during the spin operation of the spin tub by adding weight
in the form of an annular balance ring at the top of the
spin tub. The balance ring is in the form of a separable
part that is bolted in place at the top of the spin tub,
lcm/MLS
-- 6 --
and is therefore easily removable and replaceable without
complete disassembly or removal of the spin tub. The
balance weight is in the form of a heavy, rigid material,
such as a form of concrete having its density enhanced, if
desired, by incorporating denser material such as a high
density aggregate material or steel shot, and it is come
pletely enclosed and encapsulated in an outer supporting
structure, such as a suitable plastic material.
According to another aspect of this invention,
also as defined in the aforementioned parent application,
the annular balance ring incorporating the heavy material
is so mounted that it makes a substantially close sealing
fit against the inner surface of the spin tub adjacent the
upper opening thereof, and extends a distance radially
inwardly toward the axis of rotation as to provide a
clothes guard to prevent the escape of articles of clothing
within the spin tub outwardly into the area between the
spin tub and the outer tub. Accordingly, the radially
inner edge of the balance ring may be configured to aid in
the clothes guard function of the balance ring.
According to the invention of this divisional
application, the outer tub is enclosed at the top by an
inwardly extending tub cover which is removable to obtain
access to the balance ring. The cover is configured to
cooperate with the upper surface of the balance ring to
prevent the escape of clothing from the spin tub, and is
also configured to cooperate with the opening in the top of
lcm/MLS
l.~Z~3~7
-- 7 --
the cabinet to prevent the escape of articles of clothing
between the outer tub and the enclosing cabinet structure.
The tub cover extends radially inward to a point somewhat
closer to the axis of rotation than the innermost points of
the balance ring and clothes guard member, wherein it is
provided with a number of vertical spray channels. The
incoming water passes into a tubular manifold extending
around the underside of the tub cover, and has discharge
openings designed, during the fill and spray rinse opera-
lions, to direct a jet of water against a wall of the end-s
of the spray channels on the tub cover to break up the
stream and provide a downwardly directed spray of water at
spaced places around the periphery of the spin tub and onto
the clothes adjacent the wall of the spin tub.
In summary, therefore, the present invention may
be broadly considered as providing a washing machine having
an outer tub with an open top, a spin tub mounted inside
the outer tub for rotation about a vertical axis and having
an open upper end adjacent the outer tub open top, an
annular top cap secured to the outer tube open top and
extending radially inward to an inner peripheral wall radix
ally inward of the spin tub open upper end, the top cap
inner peripheral wall having a plurality of spray channels
opening downwardly into the spin tub, each of the spray
channels including a vertical wall portion, and a spray
tube secured to the top cap on the bottom side thereof and
extending around the top cap to each of the spray channels,
lcm/MLS
~Z;~7~
- pa -
the spray tube having a discharge opening adjacent each
spray channel positioned to spray water against the Verdi-
eel wall for deflection into the spin tub.
These and other aspects and advantages of the
invention are more fully described in the following de-
tailed description, and shown in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
_
FIG. 1 is an elevation Al view of a top loading
clothes washing machine, partially in section, in corpora-
tying the present invention;
FIG. 2 is an enlarged, fragmentary, cross-
sectional view of the balance ring and tub top Construction
of the machine shown in FIG. l;
FIG. 3 is a bottom view of the tub top cap shown
in FIGS. 1 and 2;
FIG. 4 is an enlarged, fragmentary, perspective
view, showing details of the water manifold and spray
channels;
FIG. 5 is a top elevation Al view, partly in
section, of the balance ring and clothes guard member; and
FIG. 6 is an enlarged, cross-sectional view
through the balance ring and clothes guard member taken on
line 6-6 of FIG. 5.
lcm/MLS
8'74~
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, a typical top loading
clothes washing machine includes a cabinet 10 having
sidewall panels 11 extending upwardly from a base 12.
Above the sidewalls 11 is a horizontal top wall 14 having
a centrally located, recessed portion 15 which defines an
access opening 16 and is covered by a suitably hinged
door or lid 18.
Within the cabinet 10, the washing machine
mechanism includes a support frame, indicated generally
at 20, which at its lower end includes an inverted cup 19
mounted on a dome 13 wormed on the cabinet base 12 at the
center thereof. The support frame includes braces 21
extending upwardly and outwardly prom the cup 19 to the
outer tub 22 in the upper part ox the cabinet 10 directly
above the dome 13. This arrangement allows the outer tub
22 to pivot about a point located on the center of curve-
lure of the dome 13, which is located below the base 12
and suitable friction means (not shown) are mounted
between the cup 19 and the dome 13 to dampen movement
there between. The transmission 23 is located centrally
below the outer tub 22 and is den by motor 24 through
drive bolt 25. A suitable pump 26 is mounted on top of
the motor 24 and centering springs, indicated at 27,
extend from the braces 21 down to points on the outermost
edge of the base 12 to center the support frame and outer
tub along a vertical axis to ensure that the outer tub 22
will be centered with respect to the access opening 16.
A spin tub 30 is mounted inside the outer tub 22
for rotation about a vertical axis and is driven by the
motor 24 through the transmission 23. The transmission
23 may also drive a suitable agitator trot shown) within
the spin tub which is normally non-rotating when the
I 37~
agitator is in operation while the spin tub 30 is rotated
at a relatively high rate of speed for the centrifugal
extraction portion of the washing cycle. The spin tub 30
has a circular, peripheral wall 32 extending closely
adjacent the cylindrical sidewall 34 of the outer tub I
and at its upper end the wall 32 has a reduced diameter
neck 36 and an outwardly flaring upper end 37 terminating
at an edge 380
A balance ring or weight ring 40 is mounted
within the spin tub 30, and rests on the flaring portion
37 of the spin tub> where it is held in place by suitable
bolts indicated at 41~ The balance ring 40 is formed as
a hollow, annular structure of suitable plastic material,
such as a filled polypropylene, and comprises a body mom-
bier 42 and a cap 43. These members define a substanti-
ally uniform wall structure completely enclosing an annum
far space which is filled with a suitable weight mater-
tat, such as a concrete or Port land cement mixture whose
density may be increased by the use of either a heavy
aggregate or metal shot particles to give the ring the
necessary mass.
The body 42 includes a generally vertically
extending, outer wall 46, and a bottom wall 47, which is
owned to a sloping inner wall portion 48 and a vertical
inner wall portion 49 above the sloping portion 48.
These walls are all generally of uniform thickness, but
to increase the rigidity so that the ring will maintain
the necessary dimensions when filled with the liquid con-
Crete before it has set, the interior is provided with a
plurality of inner reinforcing ribs 51 on the inside of
the wall portions 46-49 at a plurality of spaced points
around the ring. At the location of one of these ribs is
a solid web 52 (see FIG. 5) which completely blocks off
the interior of the body 42 by extending fully over the
cross-sectional area of the body.
I
In order to mount the ring, the body member is
provided with a plurality of bosses 54, preferably at
least three in number, to allow the balance ring to be
mounted on the spin tub. These bosses 54 are at thick-
eyed portions of the plastic material and are provided
with a bore 55 extending angularly there through to
receive a nut 56 to which one of the bolts 41 is thread-
edgy corrected to clamp the balance King firmly in place
in the spin tub. The nuts 56 have a T-bar portion 58 on
the inner end thereof, which seats on ribs 60 formed on
either side of the boss 54 and extends downwardly along
the outer wall 46 to effectively prevent the nut 56 from
rotating. The bosses 54 project outwardly from the wall
46 a slight distance in a direction along the axis ox the
bores 55 so that the balance ring contacts the spin tab
only at these points to ensure a positive clamping action
by the bolts 41.
The cap 43 includes a horizontal top wall port
lion 62 extending radially over the open upper portion of
the body 42. The cap 43 on the outer side has a down-
warmly extending flange 64 which fits outwardly of the
body outer wall 46. likewise, on the inner edge of the
top portion 42, the cap has an inner Lange 65 similar in
shape to flange 64 extending downwardly on the inner side
of vertical inner wall 49. Above the inner flange 65 is
located an upwardly projecting thickened annular rib 66
which assists in preventing the clothes from escaping the
spin tub and ensures that the balance ring will not pro-
sent any sharp edges to the user of the washing machine.
The cap 43 may be provided with peripherally extending
rib portions 68 on its underside to provide additional
stiffness and at a point which is selected to be Cannes-
dent with the solid web 52 in the body 42, has a pair of
centering ribs 70 adapted to extend downwardly on each
I 41
side of the solid web 52 to positively position the cap
43 rotationally with respect to the body 42 during asset-
by. closely adjacent the centering ribs 70 are a pair
of vent holes 72 extending through the top wall portion
62 and 180 degrees away from the vent holes 72 is a fill
opening 74 which may be covered by a suitable cap (not
shown).
The balance ring 4Q is manufactured by molding
the body 42 and cap 43 as separate pieces and the nuts So
are pressed into the bores 55 prom the inner side and any
open bore in the nut is covered by tape. After thy cap
43 is assembled on top of the body 42, the interior being
entirely empty at this point, the two members are secured
together by vibration welding so that the bottom surface
of the top wall I of cap 43 is solidly welded to the top
portions of the outer wall 46 and vertical inner wall
49. When this has been done, a suitable concrete in
liquid form is then injected through the fill opening 749
where it flows in both directions around the periphery of
the ring until it reaches the solid web 52 on the oppo-
site side. This flow will take place in both directions,
since the air present within the hollow balance ring will
escape through the vent holes 72, and when both vent
holes 72 show the presence of the liquid concrete and all
of the air has been removed, the fill opening 74 can then
be covered and the concrete material allowed to harden.
After the concrete has hardened, the balance ring may
then be mounted in place on top of the flaring portion 37
of the spin tub 30 by means of the bolts 41.
It will therefore be seen, as shown in FIG I,
that, when mounted in place, the balance ring I goner-
ally fits close enough to the neck 36 of the flaring
portion 37 to prevent any escape of clothes from the
interior of the spin tub. Furthermore, the balance ring
~l22~4
projects a sufficient distance radially into the interior
of the spin tub that it effectively serves as a clothes
guard structure to prevent toe escape ox small articles
of clothing from the interior, particularly when the tub
is at its highest fill level. Furthermore, since the
ring has a high density and is located at the highest
point on the spin tub, when the spin tub goes into rota-
lion, the ring provides a gyroscopic stabilizing effect
to minimize movement of the tub assemblies with respect
to the cabinet of the washing machine. Additionally,
since the balance ring is held in place solely by the
bolts 41 and can be removed from above, there is no need
to remove the spin tub 30 from the washing machine to
replace the balance ring if it becomes damaged and
replacement is required.
The sidewall 34 of the outer tub I extends up-
warmly to a point higher than the top edge 38 of the spin
tub and the balance ring 40. The outer tub 22 may be
made of a suitable plastic material, such as a filled
polypropylene, or it may be made in the more usual manner
of a porcelain-enameled steel. In the plastic construe-
lion shown in FIG. 2, the sidewall 34 terminates at its
upper end in a top edge 80, and a radially extending bead
81 is formed around the tub wall on the outer side adja-
cent the top edge. The top cap or tub cover, indicated
generally at 82, is secured to the outer tub 22 and ox-
tends inwardly over the spin tub 30 and balance ring 40.
To mount the top cap 82, it is provided at its outer edge
with a pair of outer and inner walls 84 and 85 extending
downwardly on either side with the tub sidewall 34, and a
suitable sealing gasket 86 is positioned between the
walls 84 and 85 and a top tub edge 80, to prevent any
water leakage at this point. The top cap 82 is then
secured to the tub by suitable spring clips indicated at
:~lZ;~4~
13
90, which are provided at a plurality of spaced locations
around the periphery of the tub and to cap.
The top cap 82 has an inwardly extending, horn-
zontal wall 92 which, a spaced distance inward from the
outer tub sidewall 34, is joined to a vertically extend-
in annular wall 93 and a curved wall 94 which curves
inwardly and upwardly to a point located above the
balance ring 40 and having substantially the same height
above the top edge 80 as the vertical wall 93. These two
walls 93 and 94, in effect, form 8 trough to collect any
water that spills out of the tub over the top cap 82 and
are provided with suitable drain holes (not shown) where-
by any water or suds that collect in this area may drain
back through the top cap into the interior of the outer
tub 22. At the upper inner end of the curved wall 84 is
joined a top wall 96, which slopes slightly upwardly and
extends radially inwardly to a point defining a generally
circular diameter slightly less Han the inner diameter
of the balance ring 40. At this point, the top wall 96
joins a downwardly extending inner wall 98 which extends
downwardly with a slight slope to terminate at a bottom
edge 100 just above the balance ring 40 to define a
reduced opening with respect to the balance ring 40 to
prevent articles of clothing prom entering this area and
possibly passing into the peripheral space between the
spin tub and the outer tub, as previously described
herein.
The top cap 82 provides a number of functions in
the washing machine, such as mounting the water inlet, a
lint filter, and a bleach dispenser. The incoming water
to fill the machine comes from the supply lines for both
hot and cold water through solenoid valves, a vacuum
bream to the top cap, where conventionally it connects to
a sup a nozzle on the top cap for discharging the water
downwardly into the spin tub through a suitable nozzle.
However, in the present invention, it is intended thaw
the incoming fill water be deflected downward at 8
plurality of points around the periphery of the top cap
for more uniform distribution of the water during the
fill cycle and better water distribution during the
spray/rinse portion of the cycle According to the
present invention, a plurality of spray channels 102 are
formed around the inner periphery of the top cap 82 on
the inner sides of the inner wall 98. The spray channels
102 are all ox identical construction, and each includes
a deflector wall 103 extending vertically a spaced disk
lance inward of the inner wall 98 and downwardly to the
bottom edge 100 of the inner wall 980 The deflector wall
103 is enclosed by sidewalls 104 extending from the de-
elector wall 103 radially outward to the inner wall go,
as well as a sloping upper wall lost At each of the
spray channels 102, an opening 107 is formed in the inner
wall 98.
A spray tube 110 is positioned on the underside
of the top cap 82 directly below the top wall 96, and
extends substantially around the entire periphery of the
top cap 82. The spray tube 110 has an entry end 112 on
one side of the lint filter, indicated generally at 114,
and extends on a constant radius around the periphery to
the other side of the lint filter 114, where it is closed
off as indicated at 116. The spray tube 110 may be
formed of an appropriate rigid material such as polyp
ethylene or polypropylene, and a closed end 116 may be
wormed by a pinching operation wherein the sides of the
tube are welded together Jo close of the end.
Adjacent each of the spray channels 102 and
extending downwardly from the top wall 96 is an inner
post indicated at 118 molded integrally with the top cap
.
82 and being provided with a projection 120 which wits
within a suitable opening in the spray tube 110 with
relatively tight fit to positively anchor the spray tube
110 against radial movement. Radially outward of the
inner post 118 and the spray tube 110 is an outer post
122, also formed integrally with the top cap 82, extend-
in downwardly to a point adjacent the bottom edge of the
spray tube. The outer post 122 is positioned to engage
the side of the spray tube 110 and is provided with an
axial bore 123 to receive a suitable screw 124 holding a
sheet metal clamp 126 in place, with the clamp in en gas
mint with the underside of the spray tube. With this
arrangement, the spray tube 110, which has a fair amount
of natural rigidity, is firmly anchored at at least four
places around the periphery of the top cap to allow easy
assembly and disassembly if necessary for replacement.
Adjacent each of the spray channels 102, the
spray tube 110 is provided with a spray hole or opening
128 positioned in a direction to provide a water spray
from the interior of the spray tube 110 to flow inwardly
and downwardly to impinge on the deflector wall 103 of
the spray channel When the water strikes the deflector
well 103, the stream is broken up and, while confined by
the deflector wall and sidewalls 104, is directed down-
warmly onto the clothes in the interior of the spin tub,
thereby providing a spray at a plurality of points on the
interior of the spin tub. It will be seen that the con-
figuration a the spray can be varied by the number of
spray channels 102 formed around the periphery of the top
cap 82, as well as by the configuration and position of
the deflector wall 103, its position with regard to spray
tube 110, and the diameter and precise location of the
spray hole 128. It will be understood that the portico-
far configuration shown in the drawings is by way of
example, and that desired additional spray channels could
be provided around the periphery of the top cap inner
wall 98, and these spray channels could be varied in con-
figuration and the spray hole 128 varied in diameter as
required for the proper spray action.
Although the preferred embodiment of this invent
lion has been shown and described, it should be under-
stood that various modifications and rearrangements of -
the parts may be resorted to without departing from the
scope of the invention as disclosed and claimed herein.
