U.S. patent application number 10/416733 was filed with the patent office on 2004-02-26 for drum type washing machine.
Invention is credited to Yoon, Seong-No.
Application Number | 20040035155 10/416733 |
Document ID | / |
Family ID | 19699088 |
Filed Date | 2004-02-26 |
United States Patent
Application |
20040035155 |
Kind Code |
A1 |
Yoon, Seong-No |
February 26, 2004 |
Drum type washing machine
Abstract
Drum type washing machine including a tub fitted in a cabinet,
and a pair of drums fitted in the tub to be rotatable in opposite
directions, thereby permitting to obtain an excellent washing
effect as an enfire surface of laundry is made to make uniform
friction with the inner drum and the outer drum, and to prevent
entangling of the laundry as the laundry is washing during the
laundry back and forth the inner drum and the outer drum,
alternately.
Inventors: |
Yoon, Seong-No;
(Changwon-shi, KR) |
Correspondence
Address: |
MCKENNA LONG & ALDRIDGE LLP
1900 K STREET, NW
WASHINGTON
DC
20006
US
|
Family ID: |
19699088 |
Appl. No.: |
10/416733 |
Filed: |
May 14, 2003 |
PCT Filed: |
November 15, 2001 |
PCT NO: |
PCT/KR01/01948 |
Current U.S.
Class: |
68/145 ; 68/24;
68/58 |
Current CPC
Class: |
D06F 37/04 20130101;
D06F 37/06 20130101; D06F 23/02 20130101; D06F 37/304 20130101 |
Class at
Publication: |
68/145 ; 68/24;
68/58 |
International
Class: |
D06F 029/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 15, 2000 |
KR |
2000-67719 |
Claims
What is claimed is:
1. A drum type washing machine comprising: a tub fitted in a
cabinet; and, a pair of drums fitted in the tub to be rotatable in
opposite directions.
2. A drum type washing machine as claimed in claim 1, wherein the
pair of drums includes; an outer drum rotatably fitted in the tub,
and an inner drum rotatably fitted in the outer drum having a
diameter and a length smaller than the outer drum,
respectively.
3. A drum type washing machine as claimed in claim 2, wherein the
outer drum includes an inward ridge projected radially from a
circumference of the outer drum at a position opposite to a fore
end of the inner drum for maintaining sealing between the inner
drum and the outer drum.
4. A drum type washing machine as claimed in claim 3, further
comprising sealing means for preventing infiltration of water into
a gap between the ridge and the inner drum.
5. A drum type washing machine as claimed in claim 2, wherein, the
inner drum has a rear end connected to the rotor in a motor part by
an inner drum shaft, there is a stator fixed to a rear end of a
rear wall of the tub inside of the rotor, the outer drum has a rear
end fixed to an outer drum shaft, and the outer drum shaft has a
rotation force transmission device provided thereto for
transmission of the rotation force of the inner drum shaft to the
outer drum shaft.
6. A drum type washing machine as claimed in claim 5, wherein the
outer drum shaft is rotatably supported at an outer circumference
thereof on a front bearing fitted an a fore end of a gear box
housing formed in a rear wall of the tub, and the inner drum shaft
is rotatably supported at an outer circumference thereof on a rear
bearing fitted at a rear end of the bearing housing.
7. A drum type washing machine as claimed in claim 5, wherein the
rotation force transmission device includes; a gear box fixed
inside of the gear box housing having opened fore end and rear end
for allowing the inner, and outer drum shafts to pass therethrough
or be inserted therein, a sun gear fitted coaxially with the inner
drum shaft for interlocked rotation with the inner drum shaft, a
plurality of planetary gears for being rotated by receiving
rotation force from the sun gear, a shaft extension extended from
the rear end of the outer drum shaft having an inner circumference
with a gear part for engagement with the planetary gears, a carrier
having a rotation shaft in front of a base, which is a rotation
center of the planetary gears, and an extension in rear of the base
positioned between the inner drum shaft and a rear opening in the
gear box, first one way rotation means between an outside
circumference of the inner drum shaft and an inside circumference
of the outer drum shaft for permitting one way interlocked rotation
of the inner, and outer drum shafts, and second one way rotation
means between an inside circumference of the rear end opening in
the gear box and an outside circumference of the extension of the
carrier for permitting one way rotation of the carrier.
8. A drum type washing machine as claimed in claim 7, wherein the
sun gear is formed as a unit with the inner drum shaft.
9. A drum type washing machine as claimed in claim 7, wherein the
planetary gear includes two gears having radiuses, and numbers of
teeth, both different from each other fixed as one unit
coaxially.
10. A drum type washing machine as claimed in claim 7, wherein the
carrier rotates in a direction the same with a rotation direction
of the inner drum shaft centered on an axis of the inner drum shaft
as the inner drum shaft rotates.
11. A drum type washing machine as claimed in claim 7, wherein the
first, and second one way rotation means is one way bearings.
12. A drum type washing machine as claimed in claim 7, wherein
there is an oilless bearing between the outside circumference of
the inner drum shaft and the inside circumference of the extension
of the carrier.
13. A drum type washing machine as claimed in claim 12, further
comprising sealing means between an outside circumference of the
inner drum shaft in rear of the oilless bearing and an inside
circumference of the extension of the carrier.
14. A drum type washing machine as claimed in claim 7, wherein the
first one way rotation means permits opposite direction rotation of
the inner drum shaft and the outer drum shaft in washing, and holds
the outer drum shaft so as to rotate in a direction the same with
the inner drum shaft in spinning.
15. A drum type washing machine as claimed in claim 7, wherein the
second one way rotation means restricts such that the gear box and
the carrier rotate in the same direction in washing, and permits
opposite direction rotation of the gear box and the carrier in
spinning.
16. A drum type washing machine as claimed in claim 7, wherein the
shaft extension has a diameter greater than a diameter of the outer
drum shaft, and smaller than a diameter of the gear box.
17. A drum type washing machine as claimed in claim 2, wherein the
inner drum is rotated as the inner drum receives a driving force
from a driving motor separately fitted to one side of the tub, the
outer drum is fixed to the outer drum shaft at a rear end thereof,
and the outer drum shaft is provided with a rotation transmission
device for transmission of a rotation force from the inner drum
shaft to the outer drum shaft.
18. A drum type washing machine as claimed in claim 17, wherein a
power transmission to the inner drum is made by a driving motor
fitted in a lower part of the tub, a motor pulley coupled to the
driving motor, a drum pulley coupled to the inner drum shaft, and
belt means for transmitting the rotation force from the motor
pulley to the drum pulley.
19. A drum type washing machine as claimed in claim 17, wherein the
tub includes a bearing housing formed as one unit therewith at a
central part thereof having a front part and a rear part fitted
with a front bearing and a rear bearing respectively, for
supporting an outside circumference of the outer drum shaft.
20. A drum type washing machine as claimed in claim 17, wherein,
there is a gear box in rear of a rear wall of the tub for holding
the rotation transmission device therein.
21. A drum type washing machine as claimed in claim 20, wherein the
gear box includes a flange formed along an outside circumference of
a front part for fastening the gear box to the rear wall of the tub
by fastening means.
22. A drum type washing machine as claimed in claim 21, wherein the
flange has a plurality of holes along a circumference for passing
fastening means, the tub has fastening holes in the rear wall at
positions corresponding to the holes in the flange.
23. A drum type washing machine as claimed in claim 1 or 2, wherein
the drums include a plurality of lifters elongated along an axis
direction, and projected form an inside surface to a radial
direction.
24. A drum type washing machine as claimed in claim 23, wherein the
lifter on the inside surface of the inner drum has a section
becoming the smaller as it goes to a front part in an axis
direction, and the lifter on the inside surface of the outer drum
has a section becoming the smaller as it goes to a rear part in an
axis direction.
25. A drum type washing machine as claimed in claim 23, wherein the
lifter has a triangular section.
26. A drum type washing machine as claimed in claim 23, wherein the
lifter has an "M" section, to form a groove in a top part in a
radial direction.
27. A drum type washing machine as claimed in claim 23, wherein the
lifter on the inside surface of the inner drum has a helical form
for moving the laundry and water in the drum forward (door side)
along an axis direction as the inner drum rotates in washing, and
the lifter on the inside surface of the outer drum has a helical
form for moving the laundry and water in the drum backward along an
axis direction as the outer drum rotates in washing.
28. A drum type washing machine comprising: an outer drum rotatably
fitted in a tub, having a rear end an outer drum shaft fixed
thereto, the outer drum shaft having a rear end coupled to a stator
fixed to a rear end of a rear wall of the tub; an inner drum
rotatably fitted in the outer drum, having a rear end an inner drum
shaft fixed thereto, the inner drum shaft having a rear end coupled
to a rotor in the motor part; a gear box housing extended in a rear
direction from a front through hole formed in a central part in
rear of a rear wall of the tub formed as one unit with the rear
wall, to form a cavity, having a rear through hole in a rear end
thereof; a front bearing, and a rear bearing fitted in the front
through hole and the rear through hole for rotatably supporting an
outside circumference of the outer drum shaft and the outside
circumference of the inner drum shaft, respectively; and, a
rotation force transmission device including a gear box fixed
inside of the gear box housing having opened fore end and rear end
for allowing the inner, and outer drum shaft to pass therethrough
or be inserted therein, a sun gear fitted coaxially with the inner
drum shaft for interlocked rotation with the inner drum shaft, a
plurality of planetary gears for being rotated by receiving
rotation force from the sun gear, a shaft extension extended from
the rear end of the outer drum shaft having an inner circumference
with a gear part for engagement with the planetary gears, a carrier
having a rotation shaft in front of a base, which is a rotation
center of the planetary gears, and an extension in rear of the base
positioned between the inner drum shaft and a rear opening in the
gear box, first one way rotation means between an outside
circumference of the inner drum shaft and an inside circumference
of the outer drum shaft for permitting one way interlocked rotation
of the inner, and outer drum shafts, and second one way rotation
means between an inside circumference of the rear end opening in
the gear box and an outside circumference of the extension of the
carrier for permitting one way rotation of the carrier.
29. A drum type washing machine comprising: an outer drum rotatably
fitted in a tub, having a rear end an outer drum shaft fixed
thereto, the outer drum shaft having a rear end passed through a
central part of a rear wall of the tub to outside thereof; a
driving motor fitted in a lower part of the tub having a driving
shaft coupled to a motor pulley; an inner drum rotatably fitted in
the outer drum, having a rear end an inner drum shaft fixed
thereto, the inner drum shaft having a rear end coupled to a drum
pulley for receiving a rotation force from the driving motor by
means of belt means; a gear box fastened to a rear side of the rear
wall of the tub by fastening means, having openings in a front end,
and a rear end for passing, or inserting the inner, and the outer
drum shafts, and a cavity therein; a front bearing, and a rear
bearing fitted in a front part, and rear part of the bearing
housing for rotatably supporting an outside circumference of the
outer drum shaft; and, a rotation force transmission device
including a sun gear fitted coaxially with the inner drum shaft for
interlocked rotation with the inner drum shaft, a plurality of
planetary gears for being rotated by receiving rotation force from
the sun gear, a shaft extension extended from the rear end of the
outer drum shaft having an inner circumference with a gear part for
engagement with the planetary gears, a carrier having a rotation
shaft in front of a base, which is a rotation center of the
planetary gears, and an extension in rear of the base positioned
between the inner drum shaft and a rear opening in the gear box,
first one way rotation means between an outside circumference of
the inner drum shaft and an inside circumference of the outer drum
shaft for permitting one way interlocked rotation of the inner, and
outer drum shafts, and second one way rotation means between an
inside circumference of the rear end opening in the gear box and an
outside circumference of the extension of the carrier for
permitting one way rotation of the carrier.
Description
TECHNICAL FIELD
[0001] The present invention relates to a drum type washing
machine, and more particularly, to a drum type washing machine, in
which one pair of drums are mounted in a tub to be rotatable in
opposite directions for washing.
BACKGROUND ART
[0002] In general, the drum type washing machine, carrying out
washing by a friction force between a drum rotated as a driving
power of a motor part is received, and laundry in a state
detergent, washing water, and the laundry are introduced into the
drum, gives little damage to the laundry, has little entangling of
the laundry, and can provide a washing effect of pounding and
rubbing the laundry.
[0003] FIG. 1 illustrates a cross section of a related art drum
type washing machine schematically, and FIG. 2 illustrates an
enlarged view of "A" part in FIG. 1, referring to which the related
art drum type washing machine will be explained. In the following
explanation, a left side on the drawing is a front part of the drum
type washing machine, and a right side on the drawing is a rear
part of the drum type washing machine.
[0004] Referring to FIGS. 1 and 2, the related art drum type
washing machine is provided with a cylindrical tub 2 inside of a
cabinet 1, and a cylindrical drum 3 rotatably fitted inside of the
cylindrical drum 3. There is a motor housing 10a in rear of a rear
wall 2a of the tub 2 fastened thereto by fastening means 19 with a
space for fitting a front, and a rear bearing 17, and 18 for
rotatably supporting a driving shaft 3b. There are hanging springs
9 fitted between an inside of an upper part of the cabinet 1 and an
upper part of an outside of the tub 2 for holding the tub 2, and a
damper 8 between the inside of a lower part of the cabinet 1 and
the outside of a lower part of the tub 2, for attenuating vibration
of the tub 2 occurring during spinning. There is a spider 3a fixed
to a driving shaft 3b which is passed through a central part of the
tub 2, and coupled with a rotor 11 of a motor 10 part in outside of
a rear wall 2a of the tub 2. Accordingly, the rotor 11 rotates as a
voltage is applied to a stator 12 in the motor part 10, and the
driving shaft 3b rotates according to the rotation of the rotor
11.
[0005] The operation of the related art drum washing machine will
be explained.
[0006] After laundry, detergent, and washing water are introduced
into the drum 3, when power is applied to the stator 12 in the
motor part 10, the rotor 11 rotates, which rotates the driving
shaft 3b, that in turn rotates the drum 3. According to this, the
laundry in the drum 3 is washed by friction with the washing water
and the drum 3.
[0007] However, the related art drum type washing machine has the
following problems.
[0008] First, in washing the laundry by the related art drum type
washing machine, the laundry repeats cycling of being lifted up to
a certain height along an inside surface of the drum 2 while
rolling, and falling down by a lifter (not shown) on an inside
surface of the drum 2, during which washing is done by the friction
occurred between the laundry, the drum 2, and the lifter. However,
the one direction rotation of the drum 2 for a preset time period
makes the laundry in the drum 2 to continue one direction rolling,
and rotation, and falling down to the lower part of the drum, that
causes partially concentrated washing, not uniform washing
throughout the laundry, resulting in non-uniform washing, and
require much time.
[0009] Second, the continuous one direction rolling, and rotation
of the laundry during washing makes many pieces of the laundry in
the drum 2 to be liable to entangle to one another, and continue
the one direction rotation in an entangled state, to result in
damage to the laundry.
DISCLOSURE OF INVENTION
[0010] Accordingly, the present invention is directed to a drum
type washing machine that substantially obviates one or more of the
problems due to limitations and disadvantages of the related
art.
[0011] An object of the present invention is to provide a drum type
washing machine, which can prevent entangling of laundry, and
enhance a washing efficiency.
[0012] Additional features and advantages of the invention will be
set forth in the description which follows, and in part will be
apparent from the description, or may be learned by practice of the
invention. The objectives and other advantages of the invention
will be realized and attained by the structure particularly pointed
out in the written description and claims hereof as well as the
appended drawings.
[0013] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described, the drum type washing machine includes a tub fitted in a
cabinet, and a pair of drums fitted in the tub to be rotatable in
opposite directions.
[0014] The pair of drums includes an outer drum rotatably fitted in
the tub, and an inner drum rotatably fitted in the outer drum
having a diameter and a length smaller than the outer drum,
respectively.
[0015] The outer drum preferably includes an inward ridge projected
radially from a circumference of the outer drum at a position
opposite to a fore end of the inner drum for maintaining sealing
between the inner drum and the outer drum, and further provided
with sealing means for preventing infiltration of water into a gap
between the ridge and the inner drum.
[0016] The inner drum has a rear end connected to the rotor in a
motor part by an inner drum shaft, there is a stator fixed to a
rear end of a rear wall of the tub inside of the rotor, the outer
drum has a rear end fixed to an outer drum shaft, and the outer
drum shaft has a rotation force transmission device provided
thereto for transmission of the rotation force of the inner drum
shaft to the outer drum shaft.
[0017] Preferably, the outer drum shaft is rotatably supported at
an outer circumference thereof on a front bearing fitted an a fore
end of a gear box housing formed in a rear wall of the tub, and the
inner drum shaft is rotatably supported at an outer circumference
thereof on a rear bearing fitted at a rear end of the bearing
housing.
[0018] The rotation force transmission device includes a gear box
fixed inside of the gear box housing having opened fore end and
rear end for allowing the inner, and outer drum shaft to pass
therethrough or be inserted therein, a sun gear fitted coaxially
with the inner drum shaft for interlocked rotation with the inner
drum shaft, a plurality of planetary gears for being rotated by
receiving rotation force from the sun gear, a shaft extension
extended from the rear end of the outer drum shaft having an inner
circumference with a gear part for engagement with the planetary
gears, a carrier having a rotation shaft in front of a base, which
is a rotation center of the planetary gears, and an extension in
rear of the base positioned between the inner drum shaft and a rear
opening in the gear box, first one way rotation means between an
outside circumference of the inner drum shaft and an inside
circumference of the outer drum shaft for permitting one way
interlocked rotation of the inner, and outer drum shafts, and
second one way rotation means between an inside circumference of
the rear end opening in the gear box and an outside circumference
of the extension of the carrier for permitting one way rotation of
the carrier.
[0019] Preferably, the sun gear is formed as a unit with the inner
drum shaft, and the planetary gear includes two gears having
radiuses, and numbers of teeth, both different from each other
fixed as one unit coaxially.
[0020] Preferably, the carrier rotates in a direction the same with
a rotation direction of the inner drum shaft centered on an axis of
the inner drum shaft as the inner drum shaft rotates.
[0021] The first, and second one way rotation means may be one way
bearings.
[0022] Preferably, there is an oilless bearing between the outside
circumference of the inner drum shaft and the inside circumference
of the extension of the carrier, and more preferably, the drum type
washing machine further includes sealing means between an outside
circumference of the inner drum shaft in rear of the oilless
bearing and an inside circumference of the extension of the
carrier.
[0023] Preferably, the first one way rotation means permits
opposite direction rotation of the inner drum shaft and the outer
drum shaft in washing, and holds the outer drum shaft so as to
rotate in a direction the same with the inner drum shaft in
spinning.
[0024] Preferably, the second one way rotation means restricts such
that the gear box and the carrier rotate in the same direction in
washing, and permits opposite direction rotation of the gear box
and the carrier in spinning.
[0025] Preferably, the shaft extension has a diameter greater than
a diameter of the outer drum shaft, and smaller than a diameter of
the gear box.
[0026] In the meantime, the inner drum is rotated as the inner drum
receives a driving force from a driving motor separately fitted to
one side of the tub, the outer drum is fixed to the outer drum
shaft at a rear end thereof, and the outer drum shaft is provided
with a rotation transmission device for transmission of a rotation
force from the inner drum shaft to the outer drum shaft.
[0027] A power transmission to the inner drum is made by a driving
motor fitted in a lower part of the tub, a motor pulley coupled to
the driving motor, a drum pulley coupled to the inner drum shaft,
and belt means for transmitting the rotation force from the motor
pulley to the drum pulley.
[0028] The tub preferably includes a bearing housing formed as one
unit therewith at a central part thereof having a front part and a
rear part fitted with a front bearing and a rear bearing
respectively, for supporting an outside circumference of the outer
drum shaft, and there is preferably a gear box in rear of a rear
wall of the tub for holding the rotation transmission device
therein.
[0029] The gear box includes a flange formed along an outside
circumference of a front part for fastening the gear box to the
rear wall of the tub by fastening means. The flange has a plurality
of holes along a circumference for passing fastening means, and the
tub has fastening holes in the rear wall at positions corresponding
to the holes in the flange.
[0030] Preferably, the drums include a plurality of lifters
elongated along an axis direction, and projected form an inside
surface to a radial direction.
[0031] Preferably, the lifter on the inside surface of the inner
drum has a section becoming the smaller as it goes to a front part
in an axis direction, and the lifter on the inside surface of the
outer drum has a section becoming the smaller as it goes to a rear
part in an axis direction.
[0032] The lifter has a triangular section, or preferably, the
lifter has an "M" section, to form a groove in a top part in a
radial direction.
[0033] Preferably, the lifter on the inside surface of the inner
drum has a helical form for moving the laundry and water in the
drum forward (door side) along an axis direction as the inner drum
rotates in washing, and the lifter on the inside surface of the
outer drum has a helical form for moving the laundry and water in
the drum backward along an axis direction as the outer drum rotates
in washing.
[0034] In another aspect of the present invention, there is
provided a drum type washing machine including an outer drum
rotatably fitted in a tub, having a rear end an outer drum shaft
fixed thereto, the outer drum shaft having a rear end coupled to a
stator fixed to a rear end of a rear wall of the tub, an inner drum
rotatably fitted in the outer drum, having a rear end an inner drum
shaft fixed thereto, the inner drum shaft having a rear end coupled
to a rotor in the motor part, a gear box housing extended in a rear
direction from a front through hole formed in a central part in
rear of a rear wall of the tub formed as one unit with the rear
wall, to form a cavity, having a rear through hole in a rear end
thereof, a front bearing, and a rear bearing fitted in the front
through hole and the rear through hole for rotatably supporting an
outside circumference of the outer drum shaft and the outside
circumference of the inner drum shaft, respectively, and a rotation
force transmission device including a gear box fixed inside of the
gear box housing having opened fore end and rear end for allowing
the inner, and outer drum shaft to pass therethrough or be inserted
therein, a sun gear fitted coaxially with the inner drum shaft for
interlocked rotation with the inner drum shaft, a plurality of
planetary gears for being rotated by receiving rotation force from
the sun gear, a shaft extension extended from the rear end of the
outer drum shaft having an inner circumference with a gear part for
engagement with the planetary gears, a carrier having a rotation
shaft in front of a base, which is a rotation center of the
planetary gears, and an extension in rear of the base positioned
between the inner drum shaft and a rear opening in the gear box,
first one way rotation means between an outside circumference of
the inner drum shaft and an inside circumference of the outer drum
shaft for permitting one way interlocked rotation of the inner, and
outer drum shafts, and second one way rotation means between an
inside circumference of the rear end opening in the gear box and an
outside circumference of the extension of the carrier for
permitting one way rotation of the carrier.
[0035] In further aspect of the present invention, there is
provided a drum type washing machine including an outer drum
rotatably fitted in a tub, having a rear end an outer drum shaft
fixed thereto, the outer drum shaft having a rear end passed
through a central part of a rear wall of the tub to outside
thereof, a driving motor fitted in a lower part of the tub having a
driving shaft coupled to a motor pulley, an inner drum rotatably
fitted in the outer drum, having a rear end an inner drum shaft
fixed thereto, the inner drum shaft having a rear end coupled to a
drum pulley for receiving a rotation force from the driving motor
by means of belt means, a gear box fastened to a rear side of the
rear wall of the tub by fastening means, having openings in a front
end, and a rear end for passing, or inserting the inner, and the
outer drum shafts, and a cavity therein, a front bearing, and a
rear bearing fitted in a front part, and rear part of the bearing
housing for rotatably supporting an outside circumference of the
outer drum shaft, and a rotation force transmission device
including a sun gear fitted coaxially with the inner drum shaft for
interlocked rotation with the inner drum shaft, a plurality of
planetary gears for being rotated by receiving rotation force from
the sun gear, a shaft extension extended from the rear end of the
outer drum shaft having an inner circumference with a gear part for
engagement with the planetary gears, a carrier having a rotation
shaft in front of a base, which is a rotation center of the
planetary gears, and an extension in rear of the base positioned
between the inner drum shaft and a rear opening in the gear box,
first one way rotation means between an outside circumference of
the inner drum shaft and an inside circumference of the outer drum
shaft for permitting one way interlocked rotation of the inner, and
outer drum shafts, and second one way rotation means between an
inside circumference of the rear end opening in the gear box and an
outside circumference of the extension of the carrier for
permitting one way rotation of the carrier.
[0036] As has been explained, the drum type washing machine of the
present invention permits to obtain an excellent washing effect
because an entire surface of laundry is made to make uniform
friction with the inner drum and the outer drum, and to prevent
entangling of the laundry because the laundry is washed during the
laundry goes back and forth the inner drum and the outer drum,
alternately.
[0037] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory and are intended to provide further explanation of
the invention as claimed.
BRIEF DESCRIPTION OF DRAWINGS
[0038] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention:
[0039] In the drawings:
[0040] FIG. 1 illustrates a cross section of a related art drum
type washing machine schematically;
[0041] FIG. 2 illustrates an enlarged view of "A" part in FIG.
1;
[0042] FIG. 3 illustrates a cross section of a drum type washing
machine in accordance with a first preferred embodiment of the
present invention;
[0043] FIG. 4 illustrates an enlarged view of a key part of FIG.
3;
[0044] FIG. 5 illustrates a cross section of a drum type washing
machine in accordance with a second preferred embodiment of the
present invention;
[0045] FIG. 6 illustrates lifters employed in the drum type washing
machine of the present invention, schematically;
[0046] FIG. 7 illustrates a variation of a lifter employed in the
drum type washing machine of the present invention, schematically;
and,
[0047] FIG. 8 illustrates another variation of a lifter employed in
the drum type washing machine of the present invention,
schematically.
BEST MODE FOR CARRYING OUT THE INVENTION
[0048] Reference will now be made in detail to the preferred
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings. For convenience of
description, a left side on the drawing is a front side of a drum
type washing machine, and a right side on the drawing is a rear
side of the drum type washing machine.
First Embodiment
[0049] FIG. 3 illustrates a cross section of a drum type washing
machine in accordance with a first preferred embodiment of the
present invention, and FIG. 4 illustrates an enlarged view of a key
part of FIG. 3, referring to which a system and operation of the
drum type washing machine of the present invention will be
explained.
[0050] Referring to FIG. 3, the drum type washing machine in
accordance with a first preferred embodiment of the present
invention includes a tub 100 inside of a cabinet, and an outer drum
200 having an opening in a front part rotatably fitted inside of
the tub 100. There is an inner drum 300 inside of the outer drum
200 having an opening in a front part, a diameter smaller than the
outer drum 200, and a length in an axis direction coaxial with the
outer drum 200. The outer drum 200 has an inward ridge 230 at a
position opposite to a fore end of the inner drum 300, which may,
or may not be formed as one unit with the outer drum 200. There is
sealing means 330 at the fore end of the inner drum 300 adjacent to
the inward ridge 230 fastened by fastening means 330a, such as
bolt, or screw, for preventing the laundry from coming into a gap
between the inner drum 300 and the outer drum 200. The sealing
means 330 in a form of a circular ring having a diameter in
correspondence to the diameter of the inner drum 300, and a width,
is fastened along an edge of the fore end of the inner drum 300 by
the fastening means 330a. Though, the sealing means 330 may be
fitted to the inner drum 300 such that a fore end of the sealing
means 330 is in contact with the inward ridge 230, for preventing
the laundry from coming into the gap, the contact between the
sealing means 330 and the inward ridge 230 may cause problems of
friction noise, and wear during rotation of the drums 200, and 300.
Therefore, it is preferable that there is a minimum gap between the
inward ridge 230 and the sealing means 330 enough to prevent the
inward ridge 230 and the sealing means 330 from coming into
contact. The sealing means 330 is preferably formed of plastic
having little noise, and being heat, and abrasion resistant.
[0051] The inner drum 300 and the outer drum 200 of the present
invention is fitted to be rotatable by the motor part 50 connected
through a shaft in rear of the inner drum 300 and the outer drum
200, which will be explained in detail.
[0052] There is an inner drum shaft 310 having one end fixed to a
rear end of the inner drum 300, and a rear end passed through the
rear wall 120 of the tub 100, and coupled with the motor part 10 in
rear of the tub 100. There is a spider 220 fixed to a rear end of
the outer drum 200, and an outer drum shaft 210 connected to a
central part of the rear end of the outer drum 200, for taking
rotation force of the inner drum shaft 310 through a rotation force
transmission device, and first, and second one way rotation means
401, and 402, which will be explained, later. There is a gear box
housing 130 in rear of a rear wall 120 of the tub 100 having a
cavity formed as a unit with the tub 100, in which the outer drum
shaft 210, and the inner drum shaft 310 are rotatably fitted,
together with the rotation force transmission device. There is a
cylindrical gear box 90 inside of the gear box housing 130, having
openings in front, and rear part.
[0053] Referring to FIG. 4, the gear box housing 130 has a front
through hole 121 in a central part of a front part of the gear box
housing 130 (i.e., the rear wall 120 of the tub 100), and a rear
through hole 122 in a central part of rear of the gear box housing
130 with a diameter enough to pass the inner drum shaft 310. There
is a front bearing 61 in a front part of the front through hole
121, and a rear bearing 62 in a rear part of the rear through hole
122. In this instance, an inner lace of the front bearing 61
rotatably supports an outer circumference of the outer drum shaft
210, and an inner lace of the rear bearing 62 rotatably supports an
outer circumference of the inner drum shaft 310.
[0054] In the meantime, both the outer drum shaft 210 and the inner
drum shaft 310 pass through the rear wall 120 of the tub 100, and
are rotatably supported, and take rotation force of the motor part
10, in rear of the rear wall 120, which will be explained, in
detail.
[0055] The inner drum shaft 310 passes through the rear through
hole 122 of the gear box housing 130, and coupled with a rotor 50a
in the motor part 50 by known fastening means, such as bolt, and
the like, at a rear end thereof. There is a stator 50b fitted to a
rear end of the gear box housing 130, with magnets 51 of the rotor
50a devised to come opposite to the stator 50b in an outer side of
the stator 50b in a radial direction, to form a motor part 50 for
generating the rotating force by means of the rotor 50a and the
stator 50b. Accordingly, upon application of power to the motor 50,
the rotor 50a rotates in regular/reverse direction, to rotate the
inner drum 300 in regular/reverse direction too as the inner drum
shaft 310 coupled to the rotor 50a rotates.
[0056] According to the first embodiment drum type washing machine
of the present invention, the inner drum 300 and the outer drum 200
are designed to rotate in opposite directions (for an example, the
inner drum rotates in a clockwise direction, while the outer drum
rotates in a counter clockwise direction) in washing, and to rotate
in the same direction (for an example, both the inner drum, and the
outer drum rotate in the counter clockwise direction) in spinning.
The opposite direction rotation of the inner drum 300, and the
outer drum 200 is implemented by the rotation force transmission
device, and the same direction rotation of the inner drum 300, and
the outer drum 200 is implemented by the first, and second one way
rotation means 401, and 402, permitting a reverse direction
rotation of the outer drum 200 with respect to a rotation direction
of the inner drum 300 in washing, and the same direction rotation
of the inner drum 300 and the outer drum 200 in spinning.
[0057] The rotation force transmission device, and the first, and
second one way rotation means 401, and 402 will be explained, in
detail.
[0058] The spider 220 is fixed to the rear end of the outer drum
200, and the outer drum shaft 210 is fixed to a central part of
rear end of the outer drum 200. The outer drum shaft 210 has a
cylindrical shaft extension 215 extended to inside of the gear box
90, inside of which there is a gear part 215a. The shaft extension
215 has a diameter greater than a diameter of the outer drum shaft
210, and smaller than a diameter of the gear box 90. There is a sun
gear 315 coaxial to the inner drum shaft 310 for rotation together
with the inner drum shaft 310. There are a plurality of planetary
gears 71, and 72 for taking, and being rotated by a rotation force
of the sun gear 315, each of which planetary gears 71, and 72 has
two gears fitted coaxially as one unit, with different radiuses,
and number of teeth. The planetary gears 71, and 72 are supported
on respective rotation shafts 81 on a base 82 of a carrier 80, and
engaged with the gear part 215a of the shaft extension 215, for
transmission of a rotation force of the sun gear 315 to the outer
drum shaft 210. There is an extension 83 from rear of the base 82
extended to a rear direction between the inner drum shaft 310 and
the rear end opening of the gear box 90, with a gap between the
extension 83 and the outer circumference of the inner drum shaft
310. There is an oilless bearing 89 and sealing means 88 between
the extension 83 and the outer circumference of the inner drum
shaft 310 in succession for making a space between the extension 83
and the inner drum shaft 310 air tight. On the other hand, there is
sealing means 41 between the inner circumference of the outer drum
shaft 210, and the outer circumference of the inner drum shaft 310
for preventing leakage of water to the gear box 90. Also, There is
sealing means 42 between the outer circumference of the outer drum
shaft 210 and the spider 220 in rear of the outer drum 200 for
preventing leakage of water to the front bearing 61.
[0059] As has been explained, the rotation force transmission
device implements the opposite direction rotation of the inner drum
300 and the outer drum 200 of the present invention in washing.
However, the inner drum 300 and the outer drum 200 are required to
rotate in the same direction at a fast speed in spinning, to
require separate means for rotating the inner drum 300 and the
outer drum 200 in the same direction, which is implemented by the
first, and second one way rotation means 401, and 402 which will be
explained in detail.
[0060] There is the first one way rotation means 401 between the
outer circumference of the inner drum shaft 310 and the inner
circumference of the outer drum shaft 210 for one way interlocked
rotation of the inner, and outer drum shafts 310, and 210. There is
the second one way rotation means 402 between the inner
circumference of the rear end opening of the gear box 90, and the
outer circumference of the extension 83 of the carrier 80 for one
way rotation of the carrier 80. That is, the first, and second one
way rotation means 401, and 402 may be one way bearings, for
forming an interlocked rotation system in which, for an example,
when the rotor 50a is rotated in the counter clockwise direction in
spinning to rotate the inner drum rotation shaft 310 in the counter
clockwise direction, the outer drum shaft 210 is also rotated in
the counter clockwise direction like the inner drum shaft 310 by
restriction of the first one way rotation means 401. As has been
explained, when both the inner drum shaft 210, and the outer drum
shaft 310 are rotated in the counter clockwise direction, both the
sun gear 315 on the inner drum shaft 310, and the planetary gears
71, and 72 engaged with the gear part 215a of the shaft extension
215 are remained stationary. Accordingly, the carrier 80 is also
rotated in the counter clockwise direction interlocked with the
inner, and outer drum shafts 310, and 210. As has been explained,
it is needless to say that, under a state all the inner, and outer
drum shafts 310, and 210, and the carrier 80 make an interlocked,
counter clockwise rotation in spinning, the second one way rotation
means 402 is fitted so as not to restrict the rotation in a
rotation direction (counter clockwise direction) of the carrier
80.
[0061] In the meantime, the reason that the second one way rotation
means 402 is fitted such that counter clockwise rotation of the
carrier 80 is permitted, while clockwise rotation of the carrier 80
is not permitted, is as follows. That is, rotation directions of
the inner drum shaft 310 and the outer drum shaft 210 are opposite
in washing, when the carrier 80 has a rotation direction the same
with the inner drum shaft 310. In this instance, if rotation of the
carrier 80 is restricted, a rotation force of the outer drum shaft
210 can be maintained, positively.
[0062] There are two planetary gears 71, and 72 on the shaft 81 of
the carrier 80 having different radiuses and numbers of teeth, for
an appropriate adjustment of a rotation speed of the inner drum 300
and the outer drum 200 by an appropriate change of the radiuses and
the numbers of gear teeth. That is, an appropriate adjustment of a
rotation ratio of the inner drum 300 and the outer drum 200
facilitates an enhancement of the washing efficiency.
Second Embodiment
[0063] FIG. 5 illustrates a cross section of a drum type washing
machine in accordance with a second preferred embodiment of the
present invention.
[0064] Referring to FIG. 5, the drum type washing machine in
accordance with a second preferred embodiment of the present
invention includes a driving motor 30 fixed on one side of a tub
100, and a motor pulley 34 fitted on a shaft of the driving motor
30. There is a drum pulley 214 coupled to a rear end of an inner
drum shaft 310 fixed to a central part of a rear end of an inner
drum 300, and the drum pulley 214 is connected to the motor pulley
34 by belt means 35, for transmission of a rotation force of the
driving motor to the inner drum 300.
[0065] On the other end, there is an outer drum 200 having a rear
end fixed to an end of an outer drum shaft 210, which receives a
rotation force from the inner drum shaft 310 through a rotation
transmission device, and first, and second one way rotation means
401, and 402 almost identical to ones in the first embodiment.
There is a bearing housing 120a in a central part of a rear wall
120 of the tub 100 formed as one unit with the rear wall 120, and
there are a front bearing 61, and a rear bearing 62 at a front
part, and a rear part of the bearing housing 120a respectively, for
rotatably supporting an outer circumference of the outer drum shaft
210.
[0066] In the meantime, there is a cylindrical gear box 90 in rear
of the rear wall 120 of the tub 100 for holding the rotation
transmission means therein, having a flange 91 at a front part
thereof formed along an outer circumference for fastening by means
of fastening means 93, such as bolts, and the like, fastened to the
rear wall 120 of the tub 100. The flange 91 has a plurality of
holes 91a along a circumference thereof for passing the fastening
means 93, and the rear wall 120 of the tub 100 has fastening holes
121 at positions in correspondence to the holes 91a for mounting
the gear box 90 to the tub 100.
[0067] The foregoing inner drum 300 and the outer drum 200 designed
to be driven by the rotation force received from the driving motor
30 through the pulleys 34, and 214, since system and operation of
the rotation force transmission means, and the first, and second
one way rotation means 401, and 402 have identical systems and
operation with the first embodiment, detailed explanation of which
will be omitted.
[0068] In the meantime, there are a plurality of lifters each
projected from an inside surface of the inner drum 300 and the
outer drum 200 of the drum type washing machine of the present
invention in an inward radial direction, and elongated along an
axis direction of the drums, which will be explained with reference
to the attached drawings. FIG. 6 illustrates lifters employed in
the drum type washing machine of the present invention,
schematically.
[0069] Referring to FIG. 6, the lifter 360 on an inside surface of
the inner drum 300 has a helical form, so that, as shown in the
drawing, the inner drum 300 pushes the laundry, and water held in
the inner drum 300 forward along an axis direction of the inner
drum 300 as the inner drum 300 rotates in an arrow direction `a`
(for an example, a clockwise direction) in washing.
[0070] Opposite to this, the lifter 260 on an inside surface of the
outer drum 200 has a helical form, so that the outer drum 200
pushes the laundry, and water held in the outer drum 200 backward
along an axis direction of the outer drum 200 as the outer drum 200
rotates in an arrow direction `b` (for an example, a counter
clockwise direction) in washing.
[0071] Moreover, the lifter 260 has a section formed the smaller as
it goes from the front part to the rear part of the drum, and the
lifter 360 has a section formed the smaller as it goes from the
rear part to the front part of the drum. Therefore, when the outer
drum 200 and the inner drum 300 rotate in directions opposite to
each other, the laundry held in the outer drum 200 gradually moves
toward the inner drum 300 together with washing water as the
laundry repeats cycling of rolling, and being lifted upward by the
lifter 260, and falling down. The laundry moved to the inner drum
300 gradually moves toward the outer drum 200 together with washing
water as the laundry repeats cycling of rolling, and being lifted
upward by the lifter 360, and falling down. That is, as the laundry
and washing water repeat the cycling in washing, there are opposite
water flows formed on the same time in a washing space formed by
the inner drum 300 and the outer drum 200, thereby permitting an
entire surface of the laundry to make friction with entire inside
surfaces of the inner drum 300 and the outer drum 200 uniformly,
and resolving entangling of the laundry as the laundry is washed
during the laundry moves to and from the inner drum 300 and the
outer drum 200, alternately.
[0072] FIG. 7 illustrates a variation of a lifter employed in the
drum type washing machine of the present invention, schematically.
Referring to FIG. 7, the lifter 270, or 370 has a triangular
section; the lifter 270 has a section becoming the smaller as it
goes from a front part to a rear part of the drum, and the lifter
370 has a section becoming the smaller as it goes from a rear part
to a front part of the drum.
[0073] FIG. 8 illustrates another variation of a lifter employed in
the drum type washing machine of the present invention,
schematically. Referring to FIG. 8, alike the lifters in FIGS. 6
and 7, the lifter 280 has a section becoming the smaller as it goes
from a front part to a rear part of the drum, and the lifter 380
has a section becoming the smaller as it goes from a rear part to a
front part of the drum. Moreover, the lifter 280, or 380 has an "M"
section to form a groove 280a, or 380a for forming a partial vortex
at a radial inward top of the lifter 280, or 380. As explained, the
groove 280a, or 380a is formed at a radial inward top of the lifter
280, or 380 to form partial vortex at the groove 280a, or 380a in
washing, for enhancing a washing efficiency.
[0074] It will be apparent to those skilled in the art that various
modifications and variations can be made in the drum type washing
machine of the present invention without departing from the spirit
or scope of the invention. Thus, it is intended that the present
invention cover the modifications and variations of this invention
provided they come within the scope of the appended claims and
their equivalents.
Industrial Applicability
[0075] As has been explained in detail, the drum type washing
machine of the present invention has an advantage of enhanced
washing performance as the one pair of drums fitted inside of a tub
designed to rotate in opposite directions in washing, form opposite
direction water flows on the same time in a washing space of the
drums, to make an entire surface of the laundry to come into
friction with inside surfaces of the inner drum and the outer drum,
uniformly, and another advantage of preventing entangling of the
laundry since the laundry is washed as the laundry goes back and
forth the inner drum and the outer drum alternately.
* * * * *