U.S. patent application number 09/810218 was filed with the patent office on 2002-04-04 for washing machine.
Invention is credited to Ahn, Jun Ho, Park, Jin Soo.
Application Number | 20020038560 09/810218 |
Document ID | / |
Family ID | 19691760 |
Filed Date | 2002-04-04 |
United States Patent
Application |
20020038560 |
Kind Code |
A1 |
Park, Jin Soo ; et
al. |
April 4, 2002 |
Washing machine
Abstract
A washing machine, with an inner tub designed to be linearly
reciprocable along its vertical axis in addition to being rotatable
on the vertical axis during the washing or rinsing process, is
disclosed. In the washing machine, a washing tub is suspended
within a cabinet forming the profile of the washing machine and
having an openable cover at its top end. The washing tub consists
of an outer tub suspended within the cabinet and containing water
therein, and a perforated inner tub set within the outer tub. This
inner tub contains laundries therein, and washes or rinses the
laundries during the washing or rinsing process. A drive unit is
mounted to the bottom of the outer tub, and rotates and vertically
reciprocates the inner tub within a predetermined stroke. The
washing machine of this invention thus forms vertical moving
currents of water in addition to active swirling currents of water
within the inner tub, and prevents laundries from being twisted
during the washing or rinsing process. The washing machine is also
improved in its rinsing and detergent dissolving performance, and
is improved in its overall laundering effect.
Inventors: |
Park, Jin Soo; (Inchon-si,
KR) ; Ahn, Jun Ho; (Seoul-si, KR) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
19691760 |
Appl. No.: |
09/810218 |
Filed: |
March 19, 2001 |
Current U.S.
Class: |
68/156 |
Current CPC
Class: |
D06F 21/08 20130101 |
Class at
Publication: |
68/156 |
International
Class: |
D06F 021/08 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 4, 2000 |
KR |
2000-58257 |
Claims
What is claimed is:
1. A washing machine, comprising: a cabinet forming a profile of
the washing machine, and provided with an openable cover at its top
end; a washing tub suspended within said cabinet, said washing tub
consisting of: an outer tub suspended within said cabinet, and
containing water therein during a washing or rinsing process; and a
perforated inner tub set within said outer tub such that the inner
tub is linearly reciprocable along its vertical axis in addition to
being rotatable on the vertical axis, said inner tub containing
laundries therein and washing or rinsing the laundries during the
washing or rinsing process; and a drive unit used for rotating and
vertically reciprocating said inner tub within a predetermined
stroke.
2. The washing machine according to claim 1, wherein said inner tub
is set within the outer tub such that predetermined gaps are left
between upper ends of the inner and outer tubs and between lower
ends of said inner and outer tubs so as to prevent the inner tub
from coming into contact with the outer tub during a reciprocating
action of the inner tub within the outer tub.
3. The washing machine according to claim 1, wherein said drive
unit comprises: a motor shaft fixed to a center of a bottom wall of
said inner tub at its upper end; a rotor frame integrated with a
lower portion of said motor shaft; first and second magnets set on
said rotor frame, said first magnet being used for rotating the
motor shaft on the vertical axis and said second magnet being used
for vertically reciprocating the motor shaft along said vertical
axis; a stator set between said first and second magnets while
being spaced apart from said magnets at predetermined gaps; a first
stator core formed by a first coil wound around said stator, and
used for selectively rotating the first magnet when the first
stator core is electrically activated; and a second stator core
formed by a second coil wound around said stator, and used for
selectively and vertically reciprocating the second magnet.
4. The washing machine according to claim 3, wherein said rotor
frame comprises an inside hub integrated with said motor shaft, and
a disc integrally extending from a lower edge of said inside hub
outward in a radial direction, with said first magnet firmly fitted
over said inside hub and said second magnet firmly set along an
outside edge of said disc, and said stator set between the first
and second magnets.
5. The washing machine according to claim 4, wherein an upper cover
is mounted to an external surface of a bottom wall of said outer
tub at a position above the rotor frame, with said stator fixed to
a lower surface of said upper cover.
6. The washing machine according to claim 5, wherein a sleeve
bearing and a radial bearing are set within a gap between said
motor shaft and said upper cover.
7. The washing machine according to claim 6, wherein an upper
annular gap is formed between the motor shaft and an upper portion
of said inside hub, with a first coil spring set within said upper
annular gap while being stopped by said sleeve bearing at its upper
end.
8. The washing machine according to claim 4, wherein a lower cover
is mounted to the external surf ace of the bottom wall of said
outer tub while covering the bottom and outside edge of said rotor
frame.
9. The washing machine according to claim 8, wherein a sleeve
bearing and a thrust bearing are set within a gap between said
motor shaft and said lower cover.
10. The washing machine according to claim 9, wherein a lower
annular gap is formed between the motor shaft and a lower portion
of said inside hub, with a second coil spring set within said lower
annular gap while being stopped by said sleeve bearing at its lower
end.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to washing machines and, more
particularly, to a washing machine with an inner tub designed to be
linearly reciprocable along its vertical axis in addition to being
rotatable on said vertical axis, thus preventing laundries from
being twisted during the washing or rinsing process and improving
the laundering effect of the washing machine.
[0003] 2. Description of the Prior Art
[0004] FIG. 1 is a sectional view, showing the construction of a
conventional washing machine with an upright washing tub.
[0005] As shown in the drawing, the conventional washing machine
has an upright washing tub, concentrically suspended within a
cabinet 104. This cabinet 104 forms the profile of the washing
machine, and is provided with an openable cover 102 at its top end,
while the washing tub comprises an outer tub 106 and a perforated
rotary inner tub 108. The outer tub 106 is suspended within the
cabinet 104 by a plurality of suspension arms 112, and contains
water therein during the washing or rinsing process, while the
perforated inner tub 108 is concentrically set within the outer tub
106, and is rotatable to wash or rinse the laundries contained
therein. A drive motor 110 is installed at a position under the
center of the bottom wall of the washing tub to rotate the inner
tub 108 at a desired speed. The suspension arms 112 hold the outer
tub 106 of the suspended washing tub within the cabinet 104, and
act as a means for absorbing undesirable shocks or vibrations
during the operation of the washing machine.
[0006] In the drive motor 110, a rotor 120 is integrated with a
motor shaft 116, while a stator 122 surrounds the rotor 120 such
that a regular gap is formed between the rotor 120 and the stator
122.
[0007] The motor shaft 116 integrally extends from the center of
the rotor 120, and passes through the center of the bottom wall of
the outer tub 106, with a bearing 118 set closely between the outer
tub 106 and the motor shaft 116 to rotatably hold the shaft 116
relative to the outer tub 106. The upper end of the motor shaft
116, projected from the bottom wall of the outer tub 106, is fixed
to the center of the bottom wall of the inner tub 108.
[0008] In the above-mentioned drive motor 110, the rotor 120 is
integrated with the motor shaft 116, so that the shaft 116 holds
the rotor 120 at a desired position. The stator 122 is fixedly set
within a motor housing 126, which is fixed to the bottom wall of
the outer tub 106.
[0009] When such a conventional washing machine is turned on,
electric power is applied to the stator 122 of the drive motor 110,
and so a rotating magnetic field is formed in the motor 110 by the
coil wound around the stator 122, thus rotating the rotor 120
together with the motor shaft 116. The inner tub 108 of the washing
tube is thus rotated relative to the outer tub 106 by the motor
shaft 116, and forms active swirling currents of water within the
inner tub 108 thus washing or rinsing the laundries. After a
washing or rinsing process, water is discharged from the washing
tub to the outside of the cabinet 104 through a drain hose. After
the draining process, the washing machine typically performs a
dewatering process to remove water together with detergent
components from the laundries by rotating the inner tub 106 at a
high speed.
[0010] However, such a conventional washing machine is problematic
in that the inner tub of the washing tub is designed to only rotate
on its vertical axis, and so the laundries are undesirably twisted
during a washing or rinsing process. Another problem experienced in
conventional washing machines with such a washing tub resides in
that its rinsing and detergent dissolving performance is reduced,
and so the washing machine does not accomplish the desired
laundering effect.
SUMMARY OF THE INVENTION
[0011] Accordingly, the present invention has been made keeping in
mind the above problems occurring in the prior art, and an object
of the present invention is to provide a washing machine, of which
the inner tub is designed to be linearly reciprocable along its
vertical axis in addition to being rotatable on the vertical axis
during a washing or rinsing process, and which thus forms vertical
moving currents of water in addition to active swirling currents of
water within the inner tub, thus preventing laundries from being
twisted during the washing or rinsing process and which is thus
improved in its overall laundering effect.
[0012] In order to accomplish the above object, the present
invention provides a washing machine, comprising: a cabinet forming
the profile of the washing machine, and provided with an openable
cover at its top end; a washing tub suspended within the cabinet,
and consisting of an outer tub suspended within the cabinet and
containing water therein during the washing or rinsing process, and
a perforated inner tub set within the outer tub such that the inner
tub is linearly reciprocable along its vertical axis in addition to
being rotatable on the vertical axis, the inner tub containing
laundries therein and washing or rinsing the laundries during the
washing or rinsing process; and a drive unit used for rotating and
vertically reciprocating the inner tub within a predetermined
stroke.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above and other objects, features and other advantages
of the present invention will be more clearly understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0014] FIG. 1 is a sectional view, showing the construction of a
conventional washing machine with an upright washing tub;
[0015] FIG. 2 is a sectional view, showing the construction of a
washing machine in accordance with the preferred embodiment of the
present invention; and
[0016] FIG. 3 is a sectional view, showing the construction of a
drive unit for the washing machine of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] FIG. 2 is a sectional view, showing the construction of a
washing machine in accordance with the preferred embodiment of the
present invention.
[0018] As shown in the drawing, the washing machine has an upright
washing tub, concentrically suspended within a cabinet 4. This
cabinet 4 forms the profile of the washing machine, and is provided
with an openable cover 2 at its top end, while the washing tub
comprises an outer tub 6 and a perforated inner tub 8. The outer
tub 6 is suspended within the cabinet 4 by a plurality of
suspension arms 12, and contains water therein during the washing
or rinsing process. The perforated inner tub 8 is concentrically
set within the outer tub 6 such that the tub 8 is linearly
reciprocable along its vertical axis in addition to being rotatable
on the vertical axis, thus washing or rinsing laundries during the
washing or rinsing process. A drive unit 10 is installed at a
position under the center of the bottom wall of the washing tub to
rotate and vertically move the inner tub 8. The suspension arms 12
hold the outer tub 6 of the suspended washing tub within the
cabinet 4, and act as a means for absorbing undesirable shocks or
vibrations during the operation of the washing machine.
[0019] In order to prevent the inner tub 8 from being undesirably
brought into contact with the outer tub 6 during the vertical
reciprocating action of the inner tub 8 within the outer tub 6, the
inner tub 8 is set within the outer tub 6 such that a predetermined
gap is left between the two tubs 6 and 8. That is, the normal
position of the movable inner tub 8 within the outer tub 6 is set
such that the inner tub 8 does not come into contact with the outer
tub 6 at its upper and lower ends or is unexpectedly impacted by
the outer tub 6 during the vertical reciprocating action of the
inner tub 8 within the outer tub 6. Such an object is accomplished
by leaving an upper gap L.sub.1 between the upper ends of the two
tubs 6 and 8 and a lower gap L.sub.2 the lower ends of the two tubs
6 and 8. In such a case, the upper gap L.sub.1 is set such that
upper end of the outer tub 6 is positioned higher than the upper
end of the inner tub 8 in its uppermost position, while the lower
gap L.sub.2 is set such that bottom wall of the outer tub 6 is
positioned lower than the bottom wall of the inner tub 8 in its
lowermost position.
[0020] The drive unit 10 rotates and vertically reciprocates the
inner tub 8 within the outer tub 6 to form desired vertical
currents and active swirling currents of water within the inner tub
8. As best seen in FIG. 3, the drive unit 10 comprises a vertically
positioned motor shaft 20 fixed to the center of the bottom wall of
the inner tub 8 at its upper end, with a rotor frame 22 integrated
with the lower portion of the motor shaft 20. A first annular
magnet 24 is firmly fitted over the inside hub 22a of the rotor
frame 22 to rotate the motor shaft 20 on the vertical axis, while a
second annular magnet 28 is firmly set along the outside edge of
the rotor frame 22 to vertically move the motor shaft 20 in
opposite directions within a predetermined stroke. A stator 30 is
set between the first and second magnets 24 and 28 while being
spaced apart from both magnets 24 and 28 at predetermined gaps. The
drive unit 10 also comprises a first stator core 34, which is
formed by a first coil wound around the inside edge of the stator
30 and selectively rotates the first magnet 24 when the core 34 is
electrically activated. A second coil is circumferentially wound
around the outside edge of the stator 30, thus forming a second
stator core 38, which selectively and vertically moves the second
magnet 28 when the core 38 is electrically activated.
[0021] The rotor frame 22, integrated with the motor shaft 20,
comprises the inside hub 22a and a disc 22b. The inside hub 22a is
integrated with the shaft 20 by a radial rib, with upper and lower
annular gaps 61 and 62 formed between the shaft 20 and the hub 22a
at opposite positions of the radial rib. This inside hub 22a thus
has an inner diameter larger than the outer diameter of the shaft
20. The disc 22b integrally extends from the lower edge of the
inside hub 22a outward in a radial direction.
[0022] An upper cover 37 is mounted to the external surface of the
bottom wall of the outer tub 6 at a position above the rotor frame
22 using a plurality of first setscrews 51. The stator 30 is fixed
to the lower surface of the upper cover 37 using a plurality of
second setscrews 52.
[0023] A lower cover 39, having a shape covering the bottom wall
and outside edge of the rotor frame 22, is mounted to the external
surface of the bottom wall of the outer tub 6 such that the screw
holes of the lower cover 39 are aligned with the screw holes of the
upper cover 37 and are tightened together with the upper cover 27
by the first set screws 51.
[0024] In the washing machine of this invention, the motor shaft 20
must be movably held in the upper and lower covers 37 and 39 such
that the shaft 20 is rotatable and vertically movable relative to
the two covers 37 and 39. In order to accomplish the above object,
upper and lower sleeve bearings 42a and 42b are movably fitted over
the shaft 20 at positions around the two covers 37 and 39, with
both a radial bearing 44a set within the annular gap between the
upper cover 37 and the upper sleeve bearing 42a and a thrust
bearing 44b set within the annular gap between the lower cover 39
and the lower sleeve bearing 42b.
[0025] A shaft biasing means is fitted over the shaft 20 at a
predetermined position for elastically supporting the shaft 20 when
the shaft 20 vertically moves in opposite directions.
[0026] In the preferred embodiment of the present invention, the
shaft biasing means comprises first and second coil springs 48a and
48b. The first spring 48a is set within the upper annular gap 61
between the shaft 20 and the upper portion of the inside hub 22a
while being stopped by both the upper sleeve bearing 42a and the
radial rib of the rotor frame 22 at opposite ends. The second
spring 48b is set within the lower annular gap 62 between the shaft
20 and the lower portion of the inside hub 22a while being stopped
by both the lower sleeve bearing 42b and the radial rib of the
rotor frame 22 at opposite ends.
[0027] The operational effect of the washing machine of this
invention will be described herein below.
[0028] In order to perform the washing or rinsing process, the coil
of the first stator core 34 is electrically activated to rotate the
first annular magnet 24 together with the rotor frame 22. Since the
rotor frame 22 is integrated with the motor shaft 20, the rotating
action of the rotor frame 22 makes the shaft 20 rotate on its
vertical axis. Therefore, the inner tub 8 of the washing tub is
rotated in the same direction, thus forming desired active swirling
currents of water capable of effectively washing or rinsing
laundries within the inner tub 8.
[0029] In such a washing or rinsing process, the coil of the second
stator core 38 is electrically activated simultaneously with the
activation of the first stator core 34, thus vertically
reciprocating the second annular magnet 28 together with the rotor
frame 22 within a predetermined stroke. Such a vertical
reciprocating action of the rotor frame 22 makes the shaft 20 to
move vertically in opposite directions within the same stroke
because the rotor frame 22 is integrated with the motor shaft 20.
During this vertical reciprocating action of the shaft 20, the
shaft 20 is elastically supported by the two coil springs 48a and
48b.
[0030] Therefore, the inner tub 8 of the washing tub is
reciprocated together with the shaft 20, and forms desired active
vertical moving currents of water capable of more effectively
washing or rinsing laundries within the inner tub 8.
[0031] In a brief description, the inner tub 8 of the washing tub
provided within the washing machine of this invention is vertically
reciprocated within a predetermined stroke in addition to being
rotated on its vertical axis during the washing or rinsing process.
Therefore, desired active swirling currents and active vertical
moving currents of water capable of more effectively washing or
rinsing laundries are created within the inner tub 8.
[0032] On the other hand, when a dewatering process in the washing
machine is desired, the first stator core 34 is electrically
activated, while the second stator core 38 is not activated. The
inner tub 8 of the washing tub during such a dewatering process is
thus not moved in a vertical direction, but is exclusively rotated
on its vertical axis at a high speed.
[0033] As described above, the present invention provides a washing
machine, of which the inner tub of the washing tub is designed to
be linearly reciprocable along its vertical axis in addition to
being rotatable on the vertical axis during the washing or rinsing
process, thus forming vertical moving currents of water in addition
to active swirling currents of water within the inner tub. The
washing machine thus prevents laundries from being twisted during
the washing or rinsing process, and improves its rinsing and
detergent dissolving performance, and is improved in its overall
laundering effect.
[0034] Although a preferred embodiment of the present invention has
been described for illustrative purposes, those skilled in the art
will appreciate that various modifications, additions and
substitutions are possible, without departing from the scope and
spirit of the invention as disclosed in the accompanying
claims.
* * * * *