U.S. patent application number 12/308736 was filed with the patent office on 2009-11-12 for washing machine with hollow agitators.
This patent application is currently assigned to BSH Bosch und Siemens Hausgerate GmbH. Invention is credited to Uwe Mette, Uwe Ratfisch, Wilfried Wildung.
Application Number | 20090276966 12/308736 |
Document ID | / |
Family ID | 38573384 |
Filed Date | 2009-11-12 |
United States Patent
Application |
20090276966 |
Kind Code |
A1 |
Mette; Uwe ; et al. |
November 12, 2009 |
Washing machine with hollow agitators
Abstract
A washing machine includes a horizontally rotatable drum having
a drum shell. Hollow agitators are disposed on the inside of the
drum and have a base as part of the drum shell and at least one
inlet opening to allow lye into the hollow space. Outlet openings
are located on a top region of each agitator for allowing lye to
pour out upon rotation to an elevated position. A fixed barrier
located in the hollow space of each agitator serves to divide the
space to define a chamber such that upon rotation from a lowest
position, the chamber fills with lye, and upon further rotation the
lye flows out of the outlet openings.
Inventors: |
Mette; Uwe; (New Bern,
NC) ; Ratfisch; Uwe; (Berlin, DE) ; Wildung;
Wilfried; (Berlin, DE) |
Correspondence
Address: |
BSH HOME APPLIANCES CORPORATION;INTELLECTUAL PROPERTY DEPARTMENT
100 BOSCH BOULEVARD
NEW BERN
NC
28562
US
|
Assignee: |
BSH Bosch und Siemens Hausgerate
GmbH
Munchen
DE
|
Family ID: |
38573384 |
Appl. No.: |
12/308736 |
Filed: |
June 21, 2006 |
PCT Filed: |
June 21, 2006 |
PCT NO: |
PCT/EP2007/056172 |
371 Date: |
December 19, 2008 |
Current U.S.
Class: |
8/158 ;
68/17A |
Current CPC
Class: |
D06F 37/065
20130101 |
Class at
Publication: |
8/158 ;
68/17.A |
International
Class: |
D06F 39/02 20060101
D06F039/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 6, 2006 |
DE |
102006031355.0 |
Claims
1-8. (canceled)
9. A washing machine comprising: a washing drum that is driven in a
horizontally rotatable manner and located in an outer tub, the drum
comprising a drum shell; hollow agitators disposed on the inside of
the drum shell, each agitator having an agitator base comprising
part of the drum shell, the agitator base having at least one inlet
opening for allowing constituent amounts of a lye disposed in a
lower apex of the outer tub to flow into the hollow space of the
agitator; outlet openings in a top region of each agitator which is
removed from the base thereof, for allowing lye to pour out of the
hollow space of each agitator after rotation of the washing drum
moves each agitator into an elevated position; and a fixed barrier
located in the hollow space of each agitator, ascending from the
agitator base in the direction of lye flowing into the hollow
space, forming an open chamber on one side of the hollow space, and
arranged such that when the agitator is in the lowest position due
to rotation of the washing drum an upper edge of the barrier is
higher than a level of lye in the hollow space for having the open
chamber fill with lye due to lye washing over the barrier upon
further rotation of the washing drum.
10. The washing machine as claimed in claim 9, wherein the barrier
further comprises a wall running parallel to the drum shell, the
wall being inclined away from the associated inlet opening, and the
inlet opening disposed in front of the barrier in the rotation
direction.
11. The washing machine as claimed in claim 10, wherein the barrier
comprises an additional rib.
12. The washing machine as claimed in claim 10, wherein the barrier
and the chamber are formed as a trough-type insert in the agitator,
a trough base of the insert being at least partially in contact
with the agitator base.
13. The washing machine as claimed in claim 10, wherein the barrier
comprises an inwardly folded peripheral region of the inlet
opening.
14. The washing machine as claimed in claim 9, wherein the inlet
opening further comprises a scoop disposed on the drum shell, the
scoop opening in the rotation direction.
15. The washing machine as claimed in claim 9, wherein the agitator
is divided into a number of sections in a direction parallel to the
drum shell, the inlet openings of the sections being oriented
alternately toward opposing rotation directions.
16. A method for operating a washing machine, the method
comprising: providing a washing machine having a washing drum
comprising a drum shell, the washing drum drivable in a
horizontally rotating manner and located in an outer tub, hollow
agitators disposed on the inside of the drum shell, each agitator
having a base comprising part of the drum shell and having an inlet
opening, outlet openings in a top region of each agitator, and a
fixed barrier located in the hollow space of each agitator
ascending from the agitator base to form an open chamber on one
side of the hollow space; filling the outer tub with lye up to a
fill level, the fill level being below an upper edge of the fixed
barrier of the agitator when the agitator is located in the lower
apex as a result of rotation of the washing drum; rotating the
washing drum; allowing lye to flow into the inlet opening as a
result of the rotation, the inlet opening located such that as the
agitator passes through the lye, lye flows through the inlet
opening into the respective agitator, washes over the barrier and
enters the chamber, where it is stored; and further rotating the
washing drum for moving the agitator into an elevated position, the
outlet openings located at a position for having the lye flow out
of the chamber through the outlet openings in the agitator to pour
into the interior of the washing drum.
Description
[0001] The invention relates to a washing machine with a washing
drum that is driven in a horizontally rotatable manner in an outer
tub and with hollow agitators disposed on the inside of a drum
shell, each having an agitator base as part of the drum shell, in
which agitator base at least one inlet opening is incorporated,
with constituent amounts of a lye located in the lower apex of the
outer tub flowing into the hollow space of the agitator through the
corresponding inlet opening and, after a further rotation of the
washing drum into an elevated position of the agitator, pouring out
of the hollow space by way of outlet openings in the top region of
the agitator removed from the agitator base into the interior of
the washing drum, as well as a method for operating said washing
machine.
[0002] Such a washing machine is known from DE 38 03 195 A1,
wherein washing liquor flows into the hollow space through scoop
holes incorporated in the sides of the agitator ribs, pouring from
there out of outlet openings over the washing from a higher
position as the washing drum rotates. To wet the washing in both
directions of rotation, the scoop holes can be sealed by means of
moving seals located inside. The seals of the scoop holes at the
front in the direction of rotation are opened by the back pressure
of the lye or free washing liquor generated during drum rotation
and the rear scoop holes are closed correspondingly. Such an
arrangement is comparatively complex from a structural point of
view and susceptible to wear on account of the moving parts.
[0003] A further agitator rib configured as a scooping device is
known for example from DD-PS 37 560. Here paddles are disposed
within the agitator hollows. As they pass through the sump at the
bottom of the outer drum, the parts of the paddles projecting above
the drum shell scoop up washing liquor, which they convey into the
inner space of the drum during the upward movement by way of the
holes disposed in the side of the agitator. Such paddles and the
holes disposed in the sides of the agitators are however not really
suitable for wetting the washing inside the drum effectively. The
quantity of water scooped will flow away by way of the holes in the
agitator sides immediately after the agitator exits from the sump
during scooping at the back pressure then resulting at agitator
level and then flow back along the inner wall of the drum to the
sump, without having wet the washing to any significant degree. It
has already been proposed here that the device should be configured
in a different manner in the agitator ribs, for example in such a
way that during the wetting phases the scooping devices convey the
free washing liquor--in other words the quantity of lye in the
lower drum space not absorbed by the washing--into an elevated
position and pours it from there onto the washing or sprays it from
above onto the items to be washed.
[0004] A further washing machine drum with agitator ribs configured
as a scooping device is known from EP 0 245 721 A1, wherein the
agitator hollows are bounded by an agitator base disposed in the
drum contour and having paddles and are divided into chambers
perpendicular to the drum axis. At least one paddle is assigned to
each chamber, so that the paddles of respectively adjacent chambers
are assigned to different drum rotation directions and are oriented
in an opposing manner to the paddle of the adjacent chamber, with
the scooping devices being configured and disposed in such a manner
that during the wetting phase they discharge the quantities of
water into the interior of the drum at the earliest from a height
in the region of the second eighth of the drum rotation, calculated
from the lowest point, to at the latest the end of the seventh
eighth of the drum rotation. However with this arrangement the
volume of lye carried along by the agitator ribs is comparatively
small.
[0005] The object of the present invention is to provide a
structurally simple and low-wear option for wetting washing
effectively by means of agitator ribs configured as scooping
devices.
[0006] This object is achieved by a washing machine configured as
claimed in claim 1, in the manner that a fixed barrier is present
in the hollow space, ascending from the agitator base in direction
W of the inflowing lye, forming an open chamber behind it within
the hollow space, and that in the lowest position of the agitator
the upper edge of the barrier is higher than the level of the lye
and the chamber behind the upper edge can be filled by lye washing
over the barrier on further rotation of the washing drum.
[0007] Advantageous refinements will emerge from the subclaims,
also in any combination with each other.
[0008] The washing machine is equipped with a washing drum driven
in a horizontally rotatable manner about an axis A in the outer
tub. Hollow agitators, which carry the washing with them as the
drum rotates, project into the washing drum. The number of said
agitators is not restricted and is typically around three.
Incorporated in each agitator is at least one inlet opening,
through which constituent amounts of a free washing liquor located
in the lower apex (6 o'clock position) of the outer tub flow into
the associated agitator hollow; the number of inlet openings is not
restricted. After a further rotation of the agitators into an
elevated position the lye present in the agitator hollow pours into
the interior of the washing drum, typically by way of pouring
openings in the top region of the agitator.
[0009] The inlet opening is incorporated in an agitator base
disposed in the shell of the washing drum. A fixed barrier
ascending from the agitator base is also present in the agitator
hollow, forming an open chamber. Lye flowing over the barrier is
retained in the chamber. The chamber is configured and disposed in
such a manner that as the washing drum rotates through the free
washing liquor or lye the barrier can be filled with lye entering
from the associated inlet opening, even if the fill level of the
lye reserve is lower than the upper edge of the barrier. This is
achieved in that the kinetic energy of the lye flowing into the
hollow space of the agitator or its back pressure is sufficient to
overcome the barrier. As the washing drum rotates through the free
washing liquor, the lye is washed in through the inlet opening with
a kinetic energy relative to the washing drum. The lye then strikes
the barrier, washes over it and thus enters the chamber behind the
barrier. The barrier ascends from the agitator base. However it
does not have to be part of the drum contour but can be configured
as an insert for example.
[0010] As it does not have to be structured and requires no moving
parts, the barrier can be produced and incorporated easily and
economically and can be operated with a low level of wear. Because
the chamber can be filled beyond the fill level of the lye reserve
and generally demonstrates a good retaining effect, a comparatively
large quantity of lye can be carried along and poured out over the
washing. The washing effect per unit of time (washing efficiency)
enhanced in this manner means that a shorter program time can be
achieved, which in turn reduces heating time and therefore energy
consumption. On the other hand the total quantity of washing liquor
can alternatively be reduced, which, because it requires less
heating power, also reduces energy consumption as well as water
consumption.
[0011] The height, form and location of the barrier are favorably
selected so that a maximum fill results, for example as a function
of the rotation speed of the drum and the fill level of the lye.
These parameters are typically determined for the different wash
phases (wetting phase, rinse phase, etc.) by a control program, so
that the barrier can be tailored structurally to a specific washing
machine.
[0012] The barrier is advantageously inclined away from the
associated inlet opening, so that the lye can flow easily over the
barrier, which is also favorably present as a wall running parallel
to the drum shell.
[0013] The barrier can have an additional rib, which is fixed to
the drum contour, for example by riveting or welding. The chamber
can however also be a trough-type insert in the agitator, the
trough base of which is at least partially in contact with the
agitator base. The barrier then corresponds to one wall of the
trough, with the other wall being in contact for example with an
agitator side or lying parallel to this at a distance or even being
(jointly) formed by the agitator side. In a further embodiment the
barrier or wall can be configured as an inwardly folded peripheral
region of the inlet opening, for example as an inwardly peripheral
channel of the--preferably slot-type--inlet opening.
[0014] To increase the inflowing quantity of lye and lye speed it
is advantageous if the inlet opening is provided with a scooping
device disposed on the outer drum periphery, for example a scoop
opening toward the direction of rotation.
[0015] If an improved washing spray is required in both rotation
directions, the agitators can be divided into a number of sections
in a direction parallel to the drum shell, said sections being
oriented alternately toward opposing rotation directions and only
demonstrating the desired effect in these. The sections can for
example be constructed as mirror images in the rotation
direction.
[0016] The washing machine is illustrated in more detail
schematically in the exemplary embodiments below. Components with
the same functional effect are given the same reference characters
here for better clarity.
[0017] FIG. 1 shows a sketch of a segment of a washing machine with
a horizontally rotatable washing drum,
[0018] FIG. 2 shows a further sketch of a conventional washing drum
in a first rotation position,
[0019] FIG. 3 shows a further sketch of the washing drum according
to FIG. 2 in a second rotation position,
[0020] FIG. 4 shows a sketch of a washing drum of the inventive
washing machine in a rotation position similar to that of FIG.
2,
[0021] FIG. 5 shows a sketch of the washing drum according to FIG.
4 in a rotation position similar to that of FIG. 3,
[0022] FIG. 6 shows an enlarged detailed view of an inventive
washing drum with an agitator in a first embodiment,
[0023] FIG. 7 shows an enlarged detailed view of an inventive
washing drum with an agitator in a second embodiment,
[0024] FIG. 8 shows an enlarged detailed view of an inventive
washing drum with an agitator in a third embodiment.
[0025] The outer tub 1 of a washing machine in FIG. 1 has an intake
opening 2 for lye in its upper region. The lye can consist of water
or a mixture of detergent introduced from a detergent dispenser 3
together with supplied water. The base of the outer tub 1, which is
at the smallest distance possible from the washing drum 4, has a
recess 5, in which the heating element 6 required to heat the lye
(shown with a broken line) is disposed. An outlet opening 7 is
disposed at the lowest point of the recess 5, said outlet opening 7
being kept sealed by a sealing element 8, while a lye pump (not
shown) on the drain pipe 9 is not in suction mode. This sealing
element 8 has the task of keeping the space below the drain opening
7 sealed, while the detergent required to wash the washing 10 is
within the outer tub 1.
[0026] Because a little water and detergent as possible should be
used for washing, the quantity of lye required for washing has
reduced to such a degree that the washing drum 4 is only slightly
immersed in the lye at the bottom of the outer tub 1. However this
produces the problem that the washing 10 at the bottom of the
washing drum 4 no longer comes into sufficient contact with the
lye, so the washing 10 is only wet very slowly and very
incompletely. This puts the wash result at risk. The wetting of the
washing 10 with lye is improved by the deployment of agitators 11,
which are attached to the drum shell 41 and which can fill the
respective agitator hollow 13 by way of inlet openings 14 fitted
with scooping devices 12 from the lye reserve in the recess 5, as
the washing drum 4 rotates, for example in the rotation direction
shown by the arrow D. During the upward movement of the agitator 11
this scooped quantity of lye is first buffered and then only
discharged by way of outlet openings in the top region of the
agitator 11, when the agitator 11 reaches a certain height above
the washing 10 in the drum 4. The arrow R shows how the lye,
elevated in this manner, sprays over the washing 10.
[0027] In the washing drum 4 shown in a simplified manner in FIG. 2
the lowest of the three structurally identical agitators attached
to the inside is in its lowest position (lower apex, 6 o'clock
position). It is immersed here in the free washing liquor at the
bottom of the outer tub and takes lye (shown with a dotted line)
into its hollow space 13 by way of the inlet opening 14 equipped
with the gill-type scooping device 12 and incorporated in the drum
shell. Outlet openings 15 are incorporated in the top region of the
agitator 11, being above the lye level Nv here. The lye level Nv is
typically filled to a predetermined value, as specified in a wash
program, in the case of level-based filling. The rotation of the
washing drum 4 in the direction of the arrow D causes the scooping
device 12 to fill the hollow space 13 of the agitator 11 higher
than would be the case in the static state.
[0028] A further agitator 11 shown top left has already reached
such a high position that lye contained in it sprays out of the
outlet openings 15 into the interior of the drum, as shown by the
arrows R. The agitator 11 shown top right has already emptied and
can once again scoop lye out of the reserve at the bottom of the
outer tub 1 once it has completed the remainder of the
rotation.
[0029] As the lower agitator 11 (FIG. 3) rotates further, the
rotation of the washing drum 4 in the rotation direction D causes
it to reach a position, in which the lowest edge of the inlet
opening 14 corresponds to the lye level Nv. In this elevated
position of the lower agitator 11 shown here, the back pressure has
dropped to zero, so the quantity of lye in the lower agitator 11
corresponds to that in the static state, in other words the
quantity of lye is defined by the small space behind and below the
edge of the inlet opening 14. The further agitators 11 continue to
spray lye down or approach the lye reserve empty.
[0030] FIG. 4 shows agitators 11' of an inventive washing machine,
in which a slot-type inlet opening 14' is incorporated in an
agitator base 42 disposed in the drum contour. The inlet opening
14' is equipped in each instance with a paddle 12'.
[0031] In contrast to the washing drums 4 shown in FIGS. 2 and 3 a
fixed barrier 17 ascending from the agitator base 42 or the drum
shell 41 is now present in the respective hollow space 13' behind
the inlet opening 14' in the rotation direction D. The barrier 17
forms an open chamber 18 in the hollow space 13'. The open chamber
18 is thus bounded by the barrier 17, the agitator base 42 and a
side of the respective agitator 11'.
[0032] The barrier 17 of the agitators 11' is configured in a wall
shape and ascends from the respective inlet opening 14' starting at
an angle into the hollow space 13'. In the exemplary embodiment
shown here the upper edge 171 of the barrier 17 with the agitator
11' in the 6 o'clock position is higher than the lye level Nv set.
During operation of the washing machine lye is washed through the
inlet opening 14' into the hollow space 13', as shown by the arrow
W (dotted line). The kinetic energy of the lye, relative to the
washing drum 4, enables the lye to overcome the height difference
between the lye level Nv and the edge of the barrier 17. In other
words the lye washes over the barrier 17 due to its relative speed
and is retained in the chamber 18.
[0033] FIG. 5 shows the washing drum from FIG. 4 after a further
rotation in the rotation direction D. In contrast to the agitator
11 in FIG. 3 the barrier 17 now retains the lye in its chamber 18
even after a reduction in the back pressure, when the lower
agitator 11' was elevated to the lye level Nv. This allows a more
than 80% greater volume of lye to be carried along in the agitator
11' compared with the agitator 11 in FIG. 3.
[0034] During the operation of the washing machine, e.g. in a
wetting, wash or rinse phase, the outer tub is first filled with
lye, typically in a level-based manner to a fill level Nv. The
washing drum 4 is then rotated. As the agitator passes through the
lye reserve or the free washing liquor, lye flows through the inlet
opening(s) 14' into the hollow space 13'. If the fill level Nv is
lower than the base 42 of the agitator 11' in the 6 o'clock
position, corresponding to its lower apex, with the inventive
configuration of the washing drum 4 the lye can still wash over the
barrier 17 and be trapped or stored in the chamber 18.
[0035] During further rotation of the washing drum 4 the agitator
11' is moved into an elevated position, in which the lye flows out
of the chamber 18 to the outlet openings 15' and pours through
these into the washing drum 4.
[0036] The outlet openings 15' are preferably located in the upper
region of each agitator 11', the top region. This ensures that a
large volume of lye is carried along and only sprays out of the
agitator, when it is far above the washing.
[0037] The inlet opening 14' can be an individual opening, e.g. in
the form of a slot with or without gills or a number of inlet
openings can be present for each agitator base 42, e.g. a number of
slots or holes.
[0038] The agitator 11' can be divided into sections disposed
parallel to the agitator base 42, which is also parallel to the
longitudinal axis of the agitator 11'. This is particularly
advantageous, if the washing drum 4 is to carry out the moistening
process in both rotation directions. The sections can then for
example be active alternately in opposing rotation directions, e.g.
by reversing the arrangement of the structural features in respect
of the rotation direction in an alternating manner.
[0039] Of course the barrier is also advantageous in respect of
retaining lye in the agitator, when the lye level Nv is above the
edge 171 of the barrier as it passes through the lye reserve. The
volume of lye carried along is no longer as great as with an
undivided hollow space 13' but it is the same degree greater than
with a divided hollow space without a barrier.
[0040] As shown in FIG. 6, the barrier 17 can also be configured as
an additional rib 19, which in this instance is riveted for example
but can also be fixed in another manner. As shown in FIG. 7, it is
however also possible for the barrier 17 to be formed by means of a
trough-type insert 18 in the agitator 11', the trough base 201 of
which is at least partially in contact with the agitator base 42.
The trough can for example be made of metal or plastic. The barrier
17 can also be configured as an inwardly folded peripheral region
21 of the inlet opening, particularly when it is formed from a flat
material, as shown in FIG. 8.
* * * * *