U.S. patent application number 10/886709 was filed with the patent office on 2005-05-12 for drum type washing machine.
This patent application is currently assigned to SAMSUNG ELECTRONICS CO., LTD.. Invention is credited to Kim, Hyun Sook, Namkung, Koan Seog, Roh, Hyoung Hoon.
Application Number | 20050097927 10/886709 |
Document ID | / |
Family ID | 34437615 |
Filed Date | 2005-05-12 |
United States Patent
Application |
20050097927 |
Kind Code |
A1 |
Kim, Hyun Sook ; et
al. |
May 12, 2005 |
Drum type washing machine
Abstract
A drum type washing machine has axially-extending lifters
arranged around an inner peripheral surface of a rotating tub which
is upwardly inclined to allow easy laundry loading and unloading.
The lifters each have a height gradually reducing to correspond to
the inclination angle of the rotating tub from a rear end of the
rotating tub to a front end thereof. Each lifter has, at its top
portion, a wave-shaped structure including crests and valleys
alternately arranged at a certain pitch. Each of the crests and
valleys has water spray holes. The lifter includes at least one
partition plate which divides the interior of the lifter into at
least two chambers. Accordingly, wash water raised by each lifter
is uniformly sprayed throughout the length of the lifter.
Inventors: |
Kim, Hyun Sook; (Suwon-Si,
KR) ; Namkung, Koan Seog; (Hwasung-Si, KR) ;
Roh, Hyoung Hoon; (Suwon-Si, KR) |
Correspondence
Address: |
STAAS & HALSEY LLP
SUITE 700
1201 NEW YORK AVENUE, N.W.
WASHINGTON
DC
20005
US
|
Assignee: |
SAMSUNG ELECTRONICS CO.,
LTD.
|
Family ID: |
34437615 |
Appl. No.: |
10/886709 |
Filed: |
July 9, 2004 |
Current U.S.
Class: |
68/24 ; 68/139;
68/142 |
Current CPC
Class: |
D06F 23/06 20130101;
D06F 37/065 20130101; D06F 37/04 20130101 |
Class at
Publication: |
068/024 ;
068/139; 068/142 |
International
Class: |
D06F 021/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 10, 2003 |
KR |
2003-79248 |
Nov 10, 2003 |
KR |
2003-79250 |
Nov 10, 2003 |
KR |
2003-79252 |
Claims
What is claimed is:
1. A drum type washing machine comprising: a housing; a rotating
tub rotatably positioned in the housing and upwardly inclined
toward a front wall of the housing at an inclination angle; and at
least one lifter arranged on an inner peripheral surface of the
rotating tub, the lifter extending from the inner peripheral
surface of the rotating tub so that a top portion of the lifter is
horizontal with respect to the housing when the lifter is
positioned at a lowest level of the rotating tub.
2. The drum type washing machine according to claim 1, wherein the
lifter has a length extending from a rear end of the rotating tub
to a front end thereof.
3. The drum type washing machine according to claim 1, wherein the
lifter includes a plurality of water spray holes for downwardly
spraying wash water raised by the lifter at the top portion of the
lifter.
4. The drum type washing machine according to claim 1, wherein the
inclination angle of the rotating tub is substantially between
5.degree. and 15.degree..
5. The drum type washing machine according to claim 4, wherein a
height of the lifter gradually reduces as the lifter extends from a
rear end of the rotating tub to a front end thereof, and wherein
the top portion of the lifter has an angle equal to the inclination
angle of the rotating tub with respect to a bottom portion of the
lifter.
6. A drum type washing machine comprising: a housing; a rotating
tub rotatably positioned in the housing and upwardly inclined
toward a front wall of the housing at an inclination angle; and at
least one lifter arranged axially along an inner peripheral surface
of the rotating tub, the lifter having a height which gradually
reduces as the lifter extends from a rear end of the rotating tub
to a front end thereof so that a top portion of the lifter has an
angle equal to the inclination angle of the rotating tub with
respect to a bottom portion of the lifter.
7. The drum type washing machine according to claim 6, wherein the
inclination angle of the rotating tub is substantially between
5.degree. and 15.degree..
8. The drum type washing machine according to 6, wherein the top
portion of the lifter has a wave-shaped structure including a
plurality of crests and a plurality of valleys alternately arranged
at a particular pitch, and each of the crests and valleys has a
plurality of water spray holes which downwardly spray wash water
raised by the lifter.
9. The drum type washing machine according to claim 8, wherein the
water spray holes are longitudinally arranged in a plurality of
rows, and corresponding water spray holes in respective rows are
laterally aligned.
10. The drum type washing machine according to claim 6, wherein the
lifter includes in an interior of the lifter a plurality of
partition plates which divide the interior of the lifter into a
plurality of chambers.
11. The drum type washing machine according to claim 10, wherein
each partition plate is inclined toward a front end of the lifter
such that an upper end of the partition plate is closer to a front
end of the lifter than a lower end of the partition plate.
12. The drum type washing machine according to claim 10, wherein
the partition plates each have different inclination angles,
respectively.
13. The drum type washing machine according to claim 10, wherein
the partition plates are arranged at different spaces,
respectively.
14. A drum type washing machine comprising: a housing; a rotating
tub rotatably positioned in the housing and upwardly inclined
toward a front wall of the housing an inclination angle; and at
least one lifter arranged on an inner peripheral surface of the
rotating tub, the lifter including at a top portion thereof a
plurality of grooves and a plurality of protrusions.
15. The drum type washing machine according to claim 14, wherein
the top portion of the lifter has a wave-shaped structure including
a plurality of crests corresponding to the protrusions and a
plurality of valleys corresponding to the grooves, the crests and
protrusions being alternately arranged at a particular pitch, and
each of the crests and protrusions has a plurality of water spray
holes which downwardly spray wash water raised by the lifter.
16. A drum type washing machine comprising: a housing; a rotating
tub rotatably positioned in the housing and upwardly inclined
toward a front wall of the housing at an inclination angle; and at
least one lifter arranged on an inner peripheral surface of the
rotating tub, the lifter including, in an interior thereof, at
least one partition plate which divides the interior of the lifter
into at least two chambers.
17. The drum type washing machine according to claim 16, wherein
the lifter has, at a front end thereof, a height smaller than a
rear end of the lifter, and the partition plates are arranged such
that the chambers each have a same capacity.
18. The drum type washing machine according to claim 1, further
comprising: another lifter, wherein the lifters are positioned
around the rotating tub such that the lifters are circumferentially
spaced uniformly apart from one another.
19. The drum type washing machine according to claim 1, wherein a
first surface of the at least one lifter has a constant width, the
first surface being closest to a center of the rotating tub.
20. The drum type washing machine according to claim 1, wherein
each lifter includes a hollow structure which receives wash water,
the hollow structure having a plurality of openings which are open
in a direction extending from a center of the rotating tub.
21. The drum type washing machine according to claim 1, wherein the
lifter includes a plurality of water spray holes at opposite side
portions of the lifter.
22. The drum type washing machine according to claim 1, further
comprising: at least one pair of bosses formed integrally with the
lifter, the bosses extending from a first face of the lifter
closest to a center of the rotating tub, wherein each boss includes
a threaded coupling hole at an end of the each boss farthest from
the first face of the lifter.
23. The drum type washing machine according to claim 22, wherein
the lifter is attached to the rotating tub via at least one
threaded coupling screw threaded through a coupling hole positioned
on an exterior portion of the rotating tub.
24. The drum type washing machine according to claim 10, wherein
the chambers have substantially equal volumes.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Korean Application
No. 2003-79248, Korean Application No. 2003-79250, and Korean
Application No. 2003-79252, each filed Nov. 10, 2003 in the Korean
Intellectual Property Office, the entire disclosures of which are
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a drum type washing
machine, and more particularly, to a drum type washing machine in
which axially-extending lifters arranged around an inner peripheral
surface of a rotating tub upwardly inclinedly installed to allow
easy laundry loading and unloading operations have an improved
structure, thereby being capable of achieving an improvement in
wash performance.
[0004] 2. Description of the Related Art
[0005] A conventional washing machine generally includes a housing
forming an outer appearance of the washing machine, a cylindrical
water tub installed in the housing and adapted to contain wash
water, a cylindrical rotating tub rotatably installed in the water
tub and adapted to wash laundry contained therein, a drive motor
arranged in the rear of the water tub and adapted to rotate the
rotating tub, and a door hingably mounted to a front wall of the
housing.
[0006] Various lifters are protruded from an inner peripheral
surface of the rotating tub to a desired height while being
arranged to be circumferentially spaced apart from one another
around the rotating tub and to extend axially along the inner
peripheral surface of the rotating tub. When the rotating tub
rotates, the laundry and wash water in the rotating tub are raised
by the lifters in a sequential fashion, and then dropped, so that
the laundry is washed.
[0007] Openings are provided at respective front ends of the water
tub and rotating tub such that they are opened and closed by the
door. When the door is open, it is possible to put laundry into the
rotating tub through the openings or to take the laundry out of the
rotating tub through the openings. When the door is closed, the
water tub and rotating tub are sealed against the outside of the
door. In this state, a wash cycle can be carried out.
[0008] In the drum type washing machine having the above mentioned
configuration, loading or unloading of laundry is carried out
through the door mounted to the front wall of the housing. In order
to carry out the loading or unloading of laundry through the
opening of the rotating tub after opening the door, however, the
user must bend his body to lower his posture because the housing of
the above-mentioned drum type washing machine typically has a
height much lower than peoples' average height, and the opening of
the rotating tub is forwardly directed. For this reason, there is
inconvenience.
[0009] In order to eliminate such inconvenience, improved drum type
washing machines have recently been developed. In such a drum type
washing machine, the rotating tub is upwardly inclined such that
the opening thereof is upwardly directed, so that the user can
perform loading and unloading of laundry without bending his body
too much.
[0010] In such a structure in which the rotating tub is inclined, a
relatively large amount of laundry is positioned at the rear end
portion of the rotating tub, whereas a relatively small amount of
laundry is positioned at the front end portion of the rotating tub.
In particular, since the lifters on the inner peripheral surface of
the rotating tub have a constant height throughout the length of
the rotating tub, the laundry positioned at the rear end portion of
the rotating tub is stacked up to a level considerably higher than
the height of the lifters, whereas the laundry positioned at the
front end portion of the rotating tub is stacked to a level lower
than the height of the lifters.
[0011] When the rotating tub rotates in such a state, the laundry
positioned at a level higher than the height of the lifters at the
rear end portion of the rotating tub may not be lifted by the
lifters, so that it is ineffectively washed. On the other hand, the
amount of laundry lifted by the lifters at the front end portion of
the rotating tub is relatively small. As a result, the lifters
operate inefficiently.
[0012] Furthermore, the laundry not lifted by the lifters at the
rear end portion of the rotating tub may be entangled as the
lifters are rotated along with the rotating tub. As a result, the
laundry may be damaged. There is also inconvenience in that the
user must disentangle the entangled laundry after completion of the
washing process.
[0013] Meanwhile, the laundry distributed in a relatively small
amount at the front end portion of the rotating tub is easily
lifted by the lifters, and then moved toward the rear end portion
of the rotating tub. As a result, the laundry tends to bunch up at
the rear end portion of the rotating tub even more.
[0014] When the laundry is mainly positioned at the rear end
portion of the rotating tub, dynamic unbalance also occurs because
a relatively large load is applied to the rear end portion of the
rotating tub, whereas a relatively small load is applied to the
front end portion of the rotating tub. As a result, the rotating
operation of the rotating tub is inefficiently carried out.
[0015] Since the rotating tub of the conventional drum type washing
machine is upwardly inclined as it extends forwardly, and the
lifters arranged thereon have a constant height, wash water, which
is mixed with detergent and introduced into a bottom portion of the
rotating tub at the front end portions of the lifters, is raised in
accordance with an upward movement of the lifters, and then
downwardly sprayed through water spray holes provided at the
lifters. However, the amount of wash water sprayed through the
water spray holes is small. A large amount of wash water flows
toward the rear end portions of the lifters. For this reason, the
wash water is mainly sprayed by the rear end portions of the
lifters. As a result, the laundry positioned at the front end
portion of the rotating tub is insufficiently doused with the wash
water, so that the laundry is ineffectively washed.
SUMMARY OF THE INVENTION
[0016] The present invention has been made in view of the problems
involved with the above mentioned conventional drum type washing
machines, and an aspect of the invention is to provide a drum type
washing machine in which axially-extending lifters arranged around
an inner peripheral surface of a rotating tub which is upwardly
inclined have an improved structure, thereby achieving an
improvement in wash performance.
[0017] In accordance with one aspect, the present invention
provides a drum type washing machine including: a housing; a
rotating tub rotatably positioned in the housing and upwardly
inclined toward a front wall of the housing at a predetermined
angle; and at least one lifter arranged on an inner peripheral
surface of the rotating tub, the lifter protruding from the inner
peripheral surface of the rotating tub so that its top portion is
horizontal with respect to the housing when the lifter is
positioned at a lowest level of the rotating tub.
[0018] The lifter may extend from a rear end of the rotating tub to
a front end thereof.
[0019] The lifter may include, at its top portion, water spray
holes for downwardly spraying wash water raised by the lifter.
[0020] The inclination angle of the rotating tub may be about
5.degree. to 15.degree..
[0021] In accordance with another aspect, the present invention
provides a drum type washing machine including: a housing; a
rotating tub rotatably installed in the housing and upwardly
inclined toward a front wall of the housing at an inclination
angle; and at least one lifter arranged on an inner peripheral
surface of the rotating tub and axially arranged along the rotating
tub, the lifter having a height gradually reduced extending from a
rear end of the rotating tub to a front end thereof so that a top
portion of the lifter has an angle equal to the inclination angle
of the rotating tub with respect to its bottom portion.
[0022] The top portion of the lifter may have a wave-shaped
structure including crests and valleys alternately arranged at a
predetermined pitch. Each of the crests and valleys may have water
spray holes for downwardly spraying wash water raised by the
lifter.
[0023] The water spray holes may be longitudinally arranged in
rows, in which corresponding water spray holes in respective rows
are laterally aligned.
[0024] The lifter may include, in the interior thereof, partition
plates which divide the interior of the lifter into chambers.
[0025] Each partition plate may be inclined toward a front end of
the lifter such that an upper end of the partition plate is closer
to the front end of the lifter than a lower end of the partition
plate.
[0026] The partition plates may have different inclination angles,
respectively.
[0027] The partition plates may be arranged at different spaces,
respectively.
[0028] In accordance with another aspect, the present invention
provides a drum type washing machine including: a housing; a
rotating tub rotatably positioned in the housing and upwardly
inclined toward a front wall of the housing at a predetermined
angle; and at least one lifter arranged on an inner peripheral
surface of the rotating tub, the lifter including, at its top
portion, grooves and protrusions.
[0029] In accordance with still another aspect, the present
invention provides a drum type washing machine including: a
housing; a rotating tub rotatably positioned in the housing and
upwardly inclined toward a front wall of the housing at a
predetermined angle; and at least one lifter arranged on an inner
peripheral surface of the rotating tub, the lifter being including,
in the interior thereof, at least one partition plate which divides
the interior of the lifter into at least two chambers.
[0030] Additional aspects and/or advantages of the invention will
be set forth in part in the description which follows and, in part,
will be obvious from the description, or may be learned by practice
of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] These and/or other aspects and advantages of the invention
will become apparent and more readily appreciated from the
following description of the embodiments, taken in conjunction with
the accompanying drawings of which:
[0032] FIG. 1 is a sectional view schematically illustrating the
configuration of a drum type washing machine according to the
present invention;
[0033] FIG. 2 is a sectional view of the rotating tub shown in FIG.
1, illustrating a structure of lifters arranged on the rotating tub
in accordance with an embodiment of the present invention;
[0034] FIG. 3 is a perspective view of the rotating tub shown in
FIG. 1, illustrating the structure of lifters arranged on the
rotating tub;
[0035] FIG. 4 is a perspective view of one lifter shown in FIG.
2;
[0036] FIG. 5 is a cross-sectional view taken along the line V-V in
FIG. 4;
[0037] FIG. 6 is a perspective view of the rotating tub
corresponding to FIG. 3, illustrating a structure of lifters
according to another embodiment of the present invention;
[0038] FIG. 7 is a perspective view of one lifter shown in FIG. 6,
illustrating a top portion of the lifter having a wave-shaped
structure; and
[0039] FIG. 8 is a cross-sectional view taken along the line
VIII-VIII in FIG. 7, illustrating partition plates arranged in the
interior of the lifter.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] Reference will now be made in detail to the embodiments of
the present invention, examples of which are illustrated in the
accompanying drawings, wherein like reference numerals refer to the
like elements throughout. The embodiments are described below to
explain the present invention by referring to the figures.
[0041] FIG. 1 is a sectional view schematically illustrating the
configuration of a drum type washing machine according to the
present invention. As shown in FIG. 1, the drum type washing
machine according to the present invention includes a housing 1
having an approximately box shape to define an outer appearance of
the washing machine, a drum-shaped water tub 2 installed in the
housing 1 and adapted to contain wash water, a drum-shaped rotating
tub 3 rotatably positioned in the water tub 2 and including
spin-dry holes 4 at a peripheral wall of the rotating tub, and a
drive motor 5 adapted to rotate the rotating tub 3, in order to
wash and spin-dry laundry contained in the rotating tub 3.
[0042] Openings 2a and 3a are provided at respective front ends of
the water tub 2 and rotating tub 3, in order to allow laundry to be
put into the rotating tub 3 and to be taken out of the rotating tub
3. A door 6 is hingably mounted to a front wall of the housing 1,
so as to open and close the openings 2a and 3a of the water tub 2
and rotating tub 3.
[0043] Installed at the top of the housing 1 are a water supply
pipe 7 for receiving wash water from an external water supply
source, and a detergent container 8 for containing detergent, and
mixing the detergent with the wash water supplied via the water
supply pipe 7. A drain pump 9 and a drain hose 10 are installed at
the bottom of the housing 1, in order to externally drain wash
water after completion of a wash cycle.
[0044] The drive motor 5 is fixedly mounted to a rear end of the
water tub 2 outside the water tub 2. A rotating shaft 5a, which is
connected to the drive motor 5 at one end thereof, is fixedly
coupled to a rear end of the rotating tub 3 at the other end of the
rotating shaft, so that it transmits a rotating force from the
drive motor 5 to the rotating tub 3, thereby causing the rotating
tub 3 to rotate.
[0045] The rotating tub 3 is upwardly inclined at a certain angle
.alpha. (FIG. 2) toward the front wall of the housing 1, in order
to allow the user to perform loading and unloading of laundry
without bending his body. Similarly, the water tub 2 is upwardly
inclined at an angle equal to the inclination angle .alpha. of the
rotating tub 3, while being suspended in the housing 1. Of course,
the water tub 2 and rotating tub 3 have different inclination
angles in some cases.
[0046] It is advantageous that the inclination angle .alpha. of the
rotating tub 3 be as large as possible, in order to conveniently
perform loading and unloading of laundry in front of the housing 1.
However, where the inclination angle .alpha. is excessively large,
the amount of laundry positioned at a rear end portion of the
rotating tub 3 increases excessively, so that a degradation in wash
performance occurs. Accordingly, it is desirable to determine the
inclination angle .alpha. of the rotating tub 3 within a range from
about 5.degree. to about 15.degree., taking into consideration the
convenience in laundry loading and unloading operations, and the
wash performance.
[0047] Lifters 20 are arranged on an inner peripheral surface of
the rotating tub 3 such that they are circumferentially uniformly
spaced apart from one another around the rotating tub 3 while
extending axially along the rotating tub 3. As the rotating tub 3
rotates, the lifters 20 raise laundry contained in the rotating tub
3, along with wash water, and then release the raised laundry and
wash water at a certain level, thereby causing the laundry and wash
water to be dropped. Thus, the laundry is washed.
[0048] Due to the arrangement of the rotating tub 3 upwardly
inclined toward the front wall of the housing 1, the laundry
contained in the rotating tub 3 may be mainly positioned at the
rear end portion of the rotating tub 3 adjacent to the rear wall of
the housing 1, as compared to the front end portion of the rotating
tub 3 adjacent to the door 6. In order to effectively lift the
laundry positioned in such a state, the lifters 20 have a height
decreasing gradually as they extend from the rear end of the
rotating tub 3 to the front end thereof. Such a structure of the
lifters 20 will be described hereinafter, with reference to FIGS. 2
to 5.
[0049] FIGS. 2 and 3 are sectional and perspective views
illustrating the structure of the lifters arranged on the inner
peripheral surface of the rotating tub shown in FIG. 1,
respectively.
[0050] As shown in FIG. 2, the rotating tub 3 is upwardly inclined
toward the front wall of the housing 1 (FIG. 1) at an angle
.alpha., so that the central axis of the rotating tub 3, that is, a
central line C.sub.1-C.sub.1, intersects a horizontal line
H.sub.1-H.sub.1 at the angle .alpha.. In accordance with this
arrangement, a relatively large amount of laundry is positioned at
the rear end portion of the rotating tub 3, as compared to the
front end portion of the rotating tub 3.
[0051] Similarly, each lifter 20 has a height gradually reduced as
it extends from the rear end of the rotating tub 3 to the front end
thereof so that lines respectively extending along top and bottom
portions 21 and 22 of the lifter 20 intersect at the angle .alpha..
In accordance with this structure, the top portion 21 of the lifter
20 is rendered parallel to the horizontal line H.sub.1-H.sub.1 when
the lifter 20 is positioned at a lowest level of the rotating tub
3.
[0052] Here, the bottom portion 22 of each lifter 20 is a lifter
portion contacting the inner peripheral surface of the rotating tub
3, whereas the top portion 21 of each lifter 20 is a lifter portion
spaced apart from the inner peripheral surface of the rotating tub
3 by a maximum distance.
[0053] In accordance with such a structure thereof, the lifters 20
can lift a relatively large amount of laundry at their rear end
portions having a relatively large height when they are positioned
at the lowest level of the rotating tub 3, while lifting a
relatively small amount of laundry at their front end portions
having a relatively small height. Accordingly, the rotating tub 3
is maintained in a dynamically balanced state, so that it can
uniformly wash all of the laundry while rotating smoothly.
[0054] Since a relatively small amount of laundry is distributed at
the front end portions of the lifters 20 having a relatively small
height during a washing process, movement of the laundry positioned
at the front end portions of the lifters 20 toward the rear end
portion of the rotating tub 3 does not occur.
[0055] As shown in FIG. 3, the lifters 20 are arranged around the
rotating tub 3 such that they are circumferentially uniformly
spaced apart from one another while extending axially from the rear
end of the rotating tub 3 to the front end thereof, that is,
throughout the length of the rotating tub 3. Accordingly, the
lifters 20 can effectively lift all of the laundry contained in the
rotating tub 3.
[0056] The top portion 21 of each lifter 20 has a constant width,
while including water spray holes 23. The water spray holes 23 are
longitudinally arranged along several lines.
[0057] Each lifter 20 also has a structure to spray wash water.
That is, each lifter 20 has a downwardly-opened hollow structure
for receiving wash water in its interior. Further, openings 27 are
provided at a portion of the rotating tub 3 to which an associated
one of the lifters 20 is coupled. Also, the bottom portion 22 of
each lifter 20 is opened to communicate with the openings 27
associated therewith. When the lifter 20 is positioned at a lowest
level thereof, wash water can be introduced into the interior of
the lifter 20 through the openings 27 associated therewith and the
opened lower end 22 thereof.
[0058] Accordingly, wash water introduced into the interior of each
lifter 20 via the opened bottom portion 22 thereof at the bottom
side of the rotating tub 3 is downwardly sprayed through the water
spray holes 23 at the top side of the rotating tub 3. Thus, the
wash water, which is mixed with detergent, can sufficiently
permeate into the laundry, so that the laundry can be rapidly
washed.
[0059] Although not shown in the drawings, spray holes may also be
provided at the opposite side portions of each lifter 20, so as to
laterally spray wash water.
[0060] As shown in FIGS. 4 and 5, a pair of bosses 24 are provided
in the interior of each lifter 20 such that they are integral with
the lifter 20. The bosses 24 protrude downwardly from an inner
surface of the top portion 21 of the lifter 20. A threaded coupling
hole 25 is formed at a protruded end of each boss 24. Accordingly,
the lifter 20 can be mounted to the rotating tub 3 by coupling
threaded screws 26 to respective coupling holes 25 outside the
rotating tub 3.
[0061] Meanwhile, the wash water introduced into the interior of
each lifter 20 via the opened bottom portion 22 thereof at the
bottom side of the rotating tub 3 may flow down toward the rear end
portion of the lifter 20 as it is moved from the bottom side of the
rotating tub 3 to the top side thereof, because the front end
portion of the lifter 20 is positioned at a level higher than the
rear end portion of the lifter 20 in accordance with the movement,
due to the structure of the lifter 20 having a height gradually
reduced toward the front end of the rotating tub 3. As a result, a
comparatively small amount of wash water is sprayed through the
water spray holes 24 at the front end portions of the lifters 20.
Rather, the wash water is mainly sprayed through the water spry
holes 24 at the rear end portions of the lifters 20.
[0062] In order to avoid such a phenomenon, each lifter has
partition plates arranged in the interior thereof. This structure
will be described hereinafter, with reference to FIGS. 4 and 5
showing an inner structure of one lifter.
[0063] Referring to FIGS. 4 and 5, the lifter 20 according to the
present invention includes first and second partition plates 31 and
32 arranged in the interior of the lifter 20 to extend laterally
while being longitudinally spaced apart from each other by a
certain distance. The interior of the lifter 20 is divided into
first through third chambers 41 to 43 by the partition plates 31
and 32.
[0064] By virtue of the first partition plate 31, wash water
contained in the first chamber 41 positioned at a relatively high
level does not flow down toward the second chamber 42 when the
associated lifter 20 is positioned at the top side of the rotating
tub 3. Similarly, wash water contained in the second chamber 42
does not flow down toward the third chamber 43 by virtue of the
second partition plate 32.
[0065] Accordingly, the wash water contained in the first chamber
41 at the front end portion of the lifter 20 is sprayed only at the
front end portion of the rotating tub 3, whereas the wash water
contained in the second chamber 42 at an intermediate portion of
the lifter 20 is sprayed only at an intermediate portion of the
rotating tub 3. Similarly, the wash water contained in the third
chamber 43 at the rear end portion of the lifter 20 is sprayed only
at the rear end portion of the rotating tub 3.
[0066] The first and second partition plates 31 and 32 are arranged
to appropriately divide the interior of the lifter 20 so that the
first through third chambers 41 to 43 have approximately equal
capacities, in order to spray approximately equal amounts of wash
water from the first through third chambers 41 to 43, respectively.
To this end, the first and second partition plates 31 and 32 are
inclined toward the front end of the lifter 20 such that the upper
end of each partition plate is closer to the front end of the
lifter 20 than the lower end of the partition plate. Also, the
first and second partition plates 31 and 32 have different
inclination angles, respectively.
[0067] In accordance with such an arrangement, the upper ends of
the first and second partition plates 31 and 32 divide the top
portion 21 of the lifter 20 into three sections respectively having
different, but approximately equal lengths. The lower ends of the
first and second partition plates 31 and 32 divide the bottom
portion 22 of the lifter 20 into three sections such that the
section corresponding to the first chamber 41 has the largest
length, and the section corresponding to the third chamber 43 has
the smallest length. Thus, the first through third chambers 41 to
43 have approximately equal capacities, respectively.
[0068] Although the lifter 20 has been illustrated as having a
structure in which three chambers 41 to 43 are defined by two
partition plates 31 and 33, an increased number of chambers may be
defined by arranging an increased number of partition plates in the
interior of the lifter. In this case, it is possible to more
uniformly spray wash water mixed with detergent through all water
spray holes formed at the top portion of the lifter.
[0069] Now, a process for washing laundry by the drum type washing
machine having the above configuration according to the present
invention will be described.
[0070] First, the user opens the door 6, and puts laundry into the
rotating tub 3 which is upwardly inclined. At this time, the user
can conveniently perform these operations without lowering his
posture. The laundry is distributed in the rotating tub 3 such that
a relatively large amount of laundry is positioned at the rear end
portion of the rotating tub 3, whereas a relatively small amount of
laundry is positioned at the front end portion of the rotating tub
3.
[0071] Thereafter, the user closes the door 6, and operates a
control panel (not shown) to operate the washing machine. As the
washing machine operates, a water supply cycle is begun. That is,
wash water mixed with detergent is introduced into the water tub 2
via the water supply pipe 7 and detergent container 8, so that it
fills a lower portion of the water tub 2. When a desired amount of
wash water corresponding to the amount of laundry to be washed is
supplied, the water supply cycle is completed. After completion of
the water supply cycle, the drive motor 5 alternatingly rotates the
rotating tub 3 in clockwise and counterclockwise directions, along
with the rotating shaft 5a. Thus, the laundry contained in the
rotating tub 3 is washed.
[0072] Although a relatively large amount of laundry is positioned
at the rear end portion of the rotating tub 3 during the wash
cycle, the lifters 20 can lift the laundry without problem because
it has, at its rear end portion, a height larger than that at its
front end portion, so that the laundry is effectively washed. Also,
the rotating tub 3 can rotate in a dynamically balanced state.
[0073] When the lifters 20 are sequentially moved to a level
adjacent to the top of the rotating tub 3 while lifting the
laundry, in accordance with rotation of the rotating tub 3, the
laundry is released from the lifters 20, and then dropped, so that
it is washed. Simultaneously, the wash water mixed with detergent
is introduced into each lifter 20 through its bottom portion 22 at
the bottom side of the rotating tub 3, and then downwardly sprayed
through the water spray holes 23 provided at the top portion 21 of
the lifter 20, so that it permeates into the laundry.
[0074] At this time, the wash water does not flow down from the
front end portion of the lifter 20 to the rear end portion thereof
because the first through third chambers 41 to 43 respectively
having approximately equal capacities are separated in the interior
of the lifter 20 by the first and second partition plates 31 and
32.
[0075] That is, the wash water contained in the first chamber 41 is
sprayed only through the water spray holes 23 formed at the front
end portion of the lifter 20, whereas the wash water contained in
the second chamber 42 is sprayed only through the water spray holes
23 formed at the intermediate portion of the lifter 20. Similarly,
the wash water contained in the third chamber 43 is sprayed only
through the water spray holes 23 formed at the rear end portion of
the lifter 20.
[0076] Accordingly, the wash water can be uniformly sprayed
throughout the length of the lifter 20. Thus, the wash water mixed
with detergent is sufficiently sprayed not only over the laundry
positioned at the rear end of the rotating tub 3, but also over the
laundry positioned at the intermediate and front end portions of
the rotating tub 3, so that the entire portion of the laundry is
uniformly wetted by the wash water.
[0077] After completion of the wash cycle, the laundry is rinsed
and spin-dried through rinse and spin-dry cycles. Thus, washing of
the laundry is completed. In the rinse cycle, all of the laundry
can also be uniformly rinsed in accordance with the function and
effect of the first and second partition plates 31 and 32.
[0078] After completion of the washing of the laundry, the user
again opens the door 6, and takes the laundry out of the rotating
tub 3. At this time, the user can conveniently perform these
operations without lowering his posture too much because the
rotating tub 3 is upwardly inclined.
[0079] FIGS. 6 to 8 illustrate a lifter structure according to
another embodiment of the present invention, respectively. FIG. 6
shows lifters arranged on the inner peripheral surface of the
rotating tub. FIG. 7 shows a lifter having a wave-shaped surface at
its top portion. FIG. 8 shows partition plates arranged in the
interior of the lifter.
[0080] Referring to FIGS. 6 and 7, a lifter 20a has a similar
structure as the lifter 20 shown in FIG. 3, except that its
surface, that is, its top portion 21, has a wave-shaped structure
including grooves and protrusions respectively having round
surfaces while being alternately arranged.
[0081] That is, the top portion 21 of the lifter 20a has an
inclined structure having a height gradually reduced toward the
front end of the rotating tub 3. Crests 21a and valleys 21b are
also alternately arranged at a certain pitch on the top portion 21
of the lifter 20a. Also, water spray holes 23 are provided at the
wave-shaped top portion 21 such that they are longitudinally
arranged in several rows. Corresponding water spray holes 23 in
respective rows are laterally aligned at each crest 21a and each
valley 21b.
[0082] Since the lifter 20a has, at its top portion 21, a
wave-shaped structure including crests 21a and valleys 21b, wash
water introduced into the interior of the lifter 20a stays at
spaces defined in the interior of the lifter 20a by the crests 21a
without immediately flowing down from the front end portion of the
lifter 20a to the rear end portion thereof, and is subsequently
sprayed toward the bottom side of the rotating tub 3 through the
water spray holes 23. Accordingly, a sufficient amount of wash
water can be sprayed even at the front end portion of the lifter
20a.
[0083] In addition, since the water spray holes 23 are
longitudinally arranged in rows along the crests 21a and valleys
21b, wash water, which has not been discharged through the water
spray holes 23 at a higher level than one of the crests 21a, flows
into a next level one of the crests 21a, and is then discharged
through the water spray holes 23 of the next level crest 21a.
[0084] Thus, the wash water does not immediately flow down from the
front end of the lifter 20a to the rear end thereof, so that the
wash water is not mainly sprayed only at the rear end of the lifter
20a.
[0085] Since the top portion 21 of the lifter 20a has a wave-shaped
structure, a frictional force is applied to the laundry in the
process of alternately rotating the rotating tub 3 in clockwise and
counter-clockwise direction.
[0086] Meanwhile, as shown in FIG. 8, the lifter 20a may include,
at its top portion 21, round crests 21a and round valleys 21b,
while also including, in the interior thereof, partition plates,
for example, the partition plates 31 and 32 of FIGS. 4 and 5.
[0087] With such a structure of the lifter 20a, wash water received
in the lifter 20a primarily stays at the spaces defined in the
interior of the lifter 20a by the crests 21a, so that the wash
water is slowed from flowing toward lower level portions of the
lifter 20a. Further, the wash water no longer flows toward the
lower level portions of the lifter 20a because of the first and
second partition plates 31 and 32. Thus, it is possible to more
effectively prevent the wash water from flowing down from the front
end portion of the lifter 20a to the rear end portion thereof.
[0088] As is apparent from the above description, in the drum type
washing machine according to one aspect of the present invention,
the rotating tub is upwardly inclined toward the front wall of the
housing, and each lifter protruded from the inner peripheral
surface of the rotating tub has a structure in which its top
portion is horizontally maintained when it is positioned at a
lowest level of the rotating tub. Accordingly, even when a
relatively large amount of laundry is distributed at the rear end
portion of the rotating tub, it is possible to lift the laundry
without problem, and thus, to rapidly and effectively wash the
laundry.
[0089] By virtue of such structures in the drum type washing
machine according to the present invention, the laundry can be
stably lifted by the lifters. Accordingly, the rotating tub can be
rotated in a dynamically stable state.
[0090] In addition, that the laundry is not entangled or lumped.
Accordingly, the rotating tub is rotated in a balanced state during
a spin-dry process. It is also unnecessary to disentangle the
washed laundry.
[0091] In the drum type washing machine according to another aspect
of the present invention, partition plates are arranged in each
lifter to define, in the interior of the lifter, chambers
respectively having approximately equal capacities. By virtue of
such a structure, wash water mixed with detergent can be uniformly
sprayed throughout the length of the lifter. Accordingly, it is
possible to rapidly and effectively wash even the laundry
distributed at the front end portion of the rotating tub positioned
at a relatively high level.
[0092] In the drum type washing machine according to another aspect
of the present invention, each lifter has a wave-shaped structure
at its top portion. Water spray holes are arranged in rows at the
crests and valleys of the wave-shaped structure. With this
structure implemented either alone or along with a plurality of
partition plates, it is possible to uniformly spray wash water
mixed with detergent throughout the length of the lifter, while
applying a frictional force to the laundry. Accordingly, the
laundry can be more rapidly and effectively washed.
[0093] Although a few embodiments of the present invention have
been shown and described, it would be appreciated by those skilled
in the art that changes may be made in this embodiment without
departing from the principles and spirit of the invention, the
scope of which is defined in the claims and their equivalents.
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