U.S. patent application number 11/058419 was filed with the patent office on 2005-09-01 for structure for supplying hot air for drying clothes in drum type washing machine and operation control method thereof.
This patent application is currently assigned to LG Electronics Inc.. Invention is credited to Ahn, Byung Hwan, Kim, Kwang Soo.
Application Number | 20050188471 11/058419 |
Document ID | / |
Family ID | 34840293 |
Filed Date | 2005-09-01 |
United States Patent
Application |
20050188471 |
Kind Code |
A1 |
Ahn, Byung Hwan ; et
al. |
September 1, 2005 |
Structure for supplying hot air for drying clothes in drum type
washing machine and operation control method thereof
Abstract
Structure for supplying hot air to a drum washing machine, and
operation control method thereof, in which uniform introduction of
hot air deep into an inside of a drum is made possible for
enhancing drying capability and efficiency. For this, a drum
washing machine includes a tub for holding washing water, a drum
rotatably mounted in the tub, for introducing laundry therein, a
drying heater for heating air being supplied to an inside of the
drum, a drying duct forming a flow passage for supplying hot air
heated by the drying heater to the inside of the drum, a fan for
forced supply of the hot air heated by the drying heater to the
inside of the drum, a hot air inlet at a front side of the drum for
supplying the hot air to the inside of the drum, and a humid air
recovery opening at a rear side of the drum for recovering humid
air from the inside of the drum, and the operation control method
of a drum washing machine includes the step of supplying hot air to
an inside of the drum while rotating the drum at a speed equal to,
or higher than a speed enough to keep the laundry in the drum
attached to, and not fall off from, the inside surface of the drum
in progressing a drying cycle.
Inventors: |
Ahn, Byung Hwan; (Gimhae-si,
KR) ; Kim, Kwang Soo; (Changwon-si, KR) |
Correspondence
Address: |
MCKENNA LONG & ALDRIDGE LLP
1900 K STREET, NW
WASHINGTON
DC
20006
US
|
Assignee: |
LG Electronics Inc.
Seoul
KR
150-721
|
Family ID: |
34840293 |
Appl. No.: |
11/058419 |
Filed: |
February 16, 2005 |
Current U.S.
Class: |
8/158 ;
68/20 |
Current CPC
Class: |
D06F 2103/08 20200201;
D06F 2105/46 20200201; D06F 25/00 20130101; D06F 58/30 20200201;
D06F 2103/10 20200201; D06F 58/38 20200201; D06F 2105/48
20200201 |
Class at
Publication: |
008/158 ;
068/020 |
International
Class: |
D06F 029/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 17, 2004 |
KR |
P2004-0010412 |
Feb 17, 2004 |
KR |
P2004-0010413 |
Claims
What is claimed is:
1. A drum washing machine comprising: a tub for holding washing
water; a drum rotatably mounted in the tub, for introducing laundry
therein; a drying heater for heating air being supplied to an
inside of the drum; a drying duct forming a flow passage for
supplying hot air heated by the drying heater to the inside of the
drum; a fan for forced supply of the hot air heated by the drying
heater to the inside of the drum; a hot air inlet at a front side
of the drum for supplying the hot air to the inside of the drum;
and a humid air recovery opening at a rear side of the drum for
recovering humid air from the inside of the drum.
2. The drum washing machine as claimed in claim 1, wherein the hot
air inlet of the drying duct is positioned at an upper portion of
the front side of the drum, and the humid air recovery opening of
the drying duct is positioned at a lower portion of the rear side
of the drum.
3. The drum washing machine as claimed in claim 1, wherein the
humid air recovery opening is connected to a rear wall of the tub
at the rear side of the drum, directly.
4. The drum washing machine as claimed in claim 3, wherein the rear
wall of the tub is formed of stainless steel or plastic, and has an
opening for recovery of humid air in a surface thereof.
5. The drum washing machine as claimed in claim 4, wherein the
opening has a shape of a slot.
6. A drum washing machine comprising: a tub for holding washing
water; a drum rotatably mounted in the tub, for introducing laundry
therein; a drying heater for heating air being supplied to an
inside of the drum; a drying duct forming a flow passage for
supplying hot air heated by the drying heater to the inside of the
drum; a fan for forced supply of the hot air heated by the drying
heater to the inside of the drum; a hot air inlet at a rear side of
the drum for supplying the hot air to the inside of the drum; and a
humid air recovery opening at a front side of the drum for
recovering humid air from the inside of the drum.
7. The drum washing machine as claimed in claim 6, wherein the hot
air inlet is positioned at an upper portion of a rear side of the
drum, and the humid air recovery opening is positioned at a lower
portion of a front side of the drum.
8. The drum washing machine as claimed in claim 6, wherein the hot
air inlet is connected to a rear wall of the tub on a rear side of
the drum.
9. The drum washing machine as claimed in claim 6, wherein the rear
wall of the tub is formed of stainless steel or plastic, and has an
opening for recovery of humid air in a surface thereof.
10. The drum washing machine as claimed in claim 9, wherein the
opening has a shape of a slot.
11. A method for controlling operation of a horizontal or tilt type
drum washing machine comprising a tub for holding washing water, a
drum rotatably mounted in the tub, for introducing laundry therein,
a drum driving motor for providing driving force to rotate the
drum, a drying heater for heating air being supplied to an inside
of the drum, a drying duct forming a flow passage for supplying hot
air heated by the drying heater to the inside of the drum, and a
fan for forced supply of the hot air heated by the drying heater to
the inside of the drum, the method comprising the step of supplying
the hot air to an inside of the drum while rotating the drum at a
speed equal to, or higher than a speed enough to keep the laundry
in the drum to be attached to, and not to fall off from, an inside
surface of the drum in progressing of a drying cycle.
12. The method as claimed in claim 11, wherein the hot air supplied
to an inside of the drum is supplied in a direction along a drum
driving shaft line.
13. The method as claimed in claim 11, wherein the hot air supplied
to an inside of the drum is supplied from a front to a rear of the
drum, or vice versa.
14. The method as claimed in claim 13, wherein the hot air supplied
to an inside of the drum is supplied from an upper side of a front
of the drum to a lower side of a rear of the drum, or from an upper
side of a rear of the drum to a lower side of a front of the
drum.
15. The method as claimed in claim 11, wherein the drying cycle
includes at least one time of; a section for turning on the drum
driving motor, to accelerate a rotation speed of the drum until the
rotation speed reaches to a preset speed equal to or higher than a
speed enough to keep the laundry in the drum to be attached to, and
not to fall off from the inside surface of the drum, and a section
for maintaining the rotation speed at the preset speed.
16. The method as claimed in claim 15, wherein the drying cycle
further includes a section for reducing the rotation speed of the
drum to a low speed at which the laundry in the drum is unable to
be attached to, but to fall off from the inside surface of the
drum, for progressing drying.
17. A method for controlling operation of a horizontal or tilt type
drum washing machine comprising a tub for holding washing water, a
drum rotatably mounted in the tub, for introducing laundry therein,
a drum driving motor for providing driving force to rotate the
drum, a drying heater for heating air being supplied to an inside
of the drum, a drying duct forming a flow passage for supplying hot
air heated by the drying heater to the inside of the drum, and a
fan for forced supply of the hot air heated by the drying heater to
the inside of the drum, the method comprising the steps of: turning
off the drum driving motor as spinning is finished; turning on the
drying heater and the fan; and supplying the hot air to an inside
of the drum while a rotation speed of the drum is maintained at a
speed enough to keep the laundry to be attached to, and not fall
off from an inside circumferential surface of the drum by turning
on the drum driving motor again before the laundry attached to the
inside circumferential surface of the drum in the spinning falls
off therefrom.
18. The method as claimed in claim 17, wherein the drying heater
and the fan are turned on at once as the spinning is finished.
19. The method as claimed in claim 17, wherein the drying heater
and the fan are turned on after a preset time period is passed from
a time when the drum driving motor is turned off.
20. The method as claimed in claim 17, wherein the hot air supplied
to an inside of the drum is supplied in a direction along a drum
driving shaft line.
21. The method as claimed in claim 17, wherein the hot air supplied
to the inside of the drum is supplied from a front to a rear of the
drum, or vice versa.
22. The method as claimed in claim 17, further comprising: a
section for maintaining a rotation speed of the drum at a speed
enough to keep the laundry to be attached to, and not fall off from
an inside circumferential surface of the drum; and a section for
reducing the rotation speed of the drum to a speed at which the
laundry in the drum is unable to be attached to, but to fall from
the inside surface of the drum.
23. A method for controlling a drying cycle of a horizontal or tilt
type drum washing machine comprising a tub for holding washing
water, a drum rotatably mounted in the tub, for introducing laundry
therein, a drying heater for heating air being supplied to an
inside of the drum, a drying duct forming a flow passage for
supplying hot air heated by the drying heater to the inside of the
drum, a fan for forced supply of the hot air heated by the drying
heater to the inside of the drum, and means for determining dryness
of the laundry in the drum, the method comprising the steps of:
measuring dryness of the laundry in the drum in a state the drum is
stationary after finish of spinning; supplying hot air while
rotating the drum at a speed equal to or higher than a speed enough
to keep the laundry to be attached to, and not to fall off from, an
inside surface of the drum by raising the rotating speed of the
drum, if measured dryness is below preset dryness; and supplying
the hot air to an inside of the drum while rotating the drum at a
speed below a speed enough to keep the laundry to be attached to,
and not to fall off from the inside surface of the drum, for
progressing drying, if the measured dryness is higher than the
preset dryness.
24. The method as claimed in claim 23, wherein the hot air supplied
to the inside of the drum is supplied in a direction the same with,
or substantially the same with, a drum driving shaft.
25. The method as claimed in claim 23, wherein the hot air supplied
to the inside of the drum is supplied from a front to a rear of the
drum, or vice versa.
26. The method as claimed in claim 23, wherein the step of
supplying the hot air to an inside of the drum while rotating the
drum at a speed below a speed enough to keep the laundry to be
attached to, and not to fall off from the inside surface of the
drum, for progressing drying includes the step of alternating a
rotating direction of the drum.
27. A method for controlling operation of a horizontal or tilt type
drum washing machine comprising a tub for holding washing water, a
drum rotatably mounted in the tub, for introducing laundry therein,
a drying heater for heating air being supplied to an inside of the
drum, a drying duct forming a flow passage for supplying hot air
heated by the drying heater to the inside of the drum, a fan for
forced supply of the hot air heated by the drying heater to the
inside of the drum, and means for determining dryness of the
laundry in the drum, the method comprising the steps of: after
spinning, supplying the hot air to the inside of the drum while
rotating the drum at a speed to maintain a state in which the
laundry is kept to be attached to, and not to fall off from, but
not to be attached closely to, an inside surface of the drum;
detecting the dryness in the middle of above step, to progress
drying while maintaining a speed to maintain a state in which the
laundry is kept to be attached to, and not to fall off from, but
not to be attached closely to, the inside surface of the drum, if
the dryness is below a preset dryness; and progressing the drying
after reducing the rotation speed of the drum to a low speed at
which the laundry is unable to be attached to, but fall off from
the inside surface of the drum, if the dryness is higher than the
preset dryness.
28. The method as claimed in claim 27, wherein the hot air supplied
to the inside of the drum is supplied in a direction the same with,
or substantially the same with, a drum driving shaft.
29. The method as claimed in claim 27, wherein the hot air supplied
to the inside of the drum is supplied from a front to a rear of the
drum, or vice versa.
30. The method as claimed in claim 27, wherein the step of
progressing the drying after reducing the rotation speed of the
drum to a low speed at which the laundry is unable to be attached
to, but fall off from the inside surface of the drum includes the
step of alternating a rotating direction of the drum.
31. A method for controlling operation of a horizontal or tilt type
drum washing machine comprising a tub for holding washing water, a
drum rotatably mounted in the tub, for introducing laundry therein,
a drying heater for heating air being supplied to an inside of the
drum, a drying duct forming a flow passage for supplying hot air
heated by the drying heater to the inside of the drum, and a fan
for forced supply of the hot air heated by the drying heater to the
inside of the drum, and a hot air supply structure in which a hot
air inlet of the drying duct is positioned at a front side or a
rear side of the drum, and a humid air recovery opening of the
drying duct is positioned at the rear side or the front side of the
drum opposite to the hot air inlet, the method comprising the steps
of: in progressing a drying cycle, supplying hot air to an inside
of the drum through the hot air inlet positioned at a front, or a
rear of the drum, and, at the same time with this, rotating the
drum at a speed enough to keep the laundry attached to, and not
fall off from, but not to be attached closely to, an inside surface
of the drum, for progressing drying.
32. The method as claimed in claim 31, wherein the hot air supplied
to an inside of the drum is supplied from an upper portion of a
front side of the drum to a lower portion of a rear side of the
drum, or an upper portion of a rear side of the drum to a lower
portion of a front side of the drum.
33. The method as claimed in claim 31, further comprising at least
one time of: a section for turning on a drum driving motor to
accelerate a rotation speed of the drum to a speed equal to, or
higher than a speed enough to keep the laundry in the drum attached
to, and not fall off from, the inside surface of the drum; a
section for maintaining the rotating speed of the drum at a speed
equal to, or higher than a speed enough to keep the laundry in the
drum attached to, and not fall off from, the inside surface of the
drum; and a section for reducing the rotating speed of the drum to
a low speed at which the laundry in the drum is unable to be
attached to, but to fall off from, the inside surface of the drum,
for progressing drying.
34. The method as claimed in claim 33, wherein the section for
reducing the rotating speed of the drum to a low speed at which the
laundry in the drum is unable to be attached to, but to fall off
from, the inside surface of the drum, for progressing drying
includes the step of alternating a rotating direction of the
drum.
35. The method as claimed in claim 31, further comprising the step
of measuring dryness of the laundry in the drum in the middle of
progressing a drying cycle.
36. The method as claimed in claim 35, wherein the dryness is
measure in a state the drum is stationary, or the rotation speed of
the drum is enough to keep the laundry attached to, and not fall
off from, the inside circumferential surface of the drum.
37. The method as claimed in claim 36, depending on a result of
measurement of the dryness, further comprising the steps of:
raising the rotating speed of the drum to maintain a speed enough
to keep the laundry attached to, and not fall off from, the inside
surface of the drum for progressing drying, if measured dryness is
below a preset dryness; and reducing the rotating speed of the drum
to a low speed at which the laundry is unable to be attached to,
but fall off from, the inside surface of the drum, for progressing
drying, if measured dryness is higher than the preset dryness.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Korean Application
Nos. P2004-0010412 and P2004-0010413, both filed on Feb. 17, 2004,
which are hereby incorporated by reference as if fully set forth
herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to drum type washing machines,
and more particularly, to a structure for supplying hot air, in
which uniform introduction of hot air deep into an inside of a drum
is made possible for enhancing drying capability and efficiency;
and an operation control method thereof.
[0004] 2. Discussion of the Related Art
[0005] In general, in the washing machines, there are a pulsator
type washing machine of a top loading type, and a drum type washing
machine (in general called as a drum washing machine) having a drum
laid down in a horizontal direction, substantially.
[0006] As described before, since the drum is laid down in a
horizontal direction, the drum washing machine performs the washing
by a method in which laundry introduced into an inside of the drum
is lifted and dropped during rotation of the drum.
[0007] Moreover, recently even demands on washing and drying
machines increase gradually, which has not only washing and water
extraction functions, but also a drying function.
[0008] Even in the drum washing machine, there are a drum washing
machine of a type the drum thereof is laid down in a horizontal
direction fully, and a tilted type drum washing machine of which
drum is tilted at an angle from a horizontal plane, and, depending
on a direction of introduction/taking out of laundry into/from the
drum, there are a front loading type, and a top loading type drum
washing machines.
[0009] FIGS. 1 and 2 illustrate basic exemplary structures of above
washing and drying machines, schematically.
[0010] That is, the washing and drying machine is provided with a
body 10, a tub 20 mounted on an inside of the body 10, a drum 30
rotatably mounted on an inside of the tub 20, washing water supply
pipes 51 for guiding flow of the washing water, a driving unit for
driving the drum 30, and a drying device for supplying heated air
to an inside of the tub 20.
[0011] On a front of the body 10, there is an opening for
introduction of laundry, with a door 40 thereon for opening/closing
the opening. Between the front of the body 10 and the tub 20, there
is a gasket 11.
[0012] The tub 20 is supported, and mounted in the body 10. There
may be a washing water drying heater 80 on a bottom of an inside of
the tub 20, for controlling a temperature of the washing water used
for washing.
[0013] The drum 30 is rotatably mounted in the tub 20, and has a
plurality of through holes 31 (see FIG. 2) in a circumferential
surface for flow in/out of the washing water.
[0014] The washing water supply pipe 51, for flow of the washing
water, guides the washing water from a service pipe to the inside
of the tub 20 through a water supply valve 52. There is a detergent
box 53 in the washing water supply pipe 51 for storing detergent
required for washing, so that the washing water being supplied to
the inside of the tub 20 carries the detergent. The detergent box
53 in an upper space of the body 10 is designed to enable
introduction of the detergent.
[0015] The washing water supply pipe 51 has an end connected to a
front of an upper portion of the tub 20 for filling up the tub 20
with the washing water from a bottom thereof by free falling of the
washing water.
[0016] The driving unit is provided with a drum driving motor 71,
and a belt 72 for transmission of a driving power from the drum
driving motor 71 to the drum 30. Recently, instead of the driving
unit, a direct coupling type BLDC motor is used, which is mounted
on a rear wall of the tub for direct transmission of the driving
power from the motor to the drum.
[0017] The drying device is provided with a drying duct 60 for flow
of air, a drying heater 61 in the drying duct 60, and a fan 62 for
forced circulation of air. The drying duct 60 has one end connected
to the tub 20 at a lower portion of a front side of an outside
circumference thereof and the other end connected to the gasket 11,
for circulation of air through the inside of the tub 20.
[0018] Connected to the drying duct 60, there is a cooling water
supply pipe 54 for supplying cooling water to the air flowing along
the drying duct 60 toward the drying heater after drying laundry to
condense moisture therein. By removing the moisture from the air,
the cooling water prevents drop of performance of the fan 62, and
drop of efficiency of the drying heater 61.
[0019] The cooling water supply pipe 54 is connected to the water
supply valve 52 for supplying washing water. The water supply valve
52 is operated such that only a very low rate of water is supplied
to the drying duct 60 compared to a rate of the washing water
supply to the drum 30 through the washing water supply pipe 51, if
water supply to the drying duct 60 through the cooling water supply
pipe 54 is required for condensing.
[0020] In the meantime, while the related art drum washing machine
progresses drying by rotating the drum 30 at a low speed (about
20.about.30 rpm) after washing, and spinning, the hot air, heated
and dried by the drying heater, is introduced into the inside of
the drum through, in general, a connection portion to the gasket 11
on the front of the drum 30, converted into humid air by the drying
action, and escapes through a lower side of a front of the drum 30
again.
[0021] That is, referring to FIGS. 1 and 3, because the drying duct
draws humid air from the front side of the outside circumference of
the tub, the hot air fails to be introduced deep into an inside of
the drum 30, but circulates only on an entrance side and is
directly discharged to a lower side of the front of the drum
30.
[0022] Therefore, since the hot air escapes the drum 30 before the
hot air can be used fully for drying in the drum 30, the drying
performance, and efficiency are impaired, and input of unnecessary
energy is required, resulting in waste of energy.
[0023] In short, with regard to a main flow path of the hot air in
the related art drum washing machine, because the hot air fails to
reach to the laundry located far from a hot air inlet fully,
failing to dry the laundry uniformly to impair the drying
performance, to require drying for a long time, the drying
efficiency is also dropped.
SUMMARY OF THE INVENTION
[0024] Accordingly, the present invention is directed to a
structure for supplying hot air in a drum washing machine and an
operation control method thereof that substantially obviates one or
more problems due to limitations and disadvantages of the related
art.
[0025] An object of the present invention is to provide a structure
for supplying hot air in a drum washing machine and an operation
control method thereof, in which hot air can be blown deep into an
inside of the drum, to introduce the hot air into an inside space
of the drum uniformly for drying the laundry. That is, the object
of the present invention is to provide a structure for supplying
hot air and an operation control method thereof, which enables full
use of the hot air introduced into the inside of the drum for
enhancing the drying performance, and efficiency.
[0026] Additional advantages, objects, and features of the
invention will be set forth in part in the description which
follows and in part will become apparent to those having ordinary
skill in the art upon examination of the following or may be
learned from practice of the invention. The objectives and other
advantages of the invention may be realized and attained by the
structure particularly pointed out in the written description and
claims hereof as well as the appended drawings.
[0027] To achieve these objects and other advantages and in
accordance with the purpose of the invention, as embodied and
broadly described herein, a drum washing machine includes a tub for
holding washing water, a drum rotatably mounted in the tub, for
introducing laundry therein, a drying heater for heating air being
supplied to an inside of the drum, a drying duct forming a flow
passage for supplying hot air heated by the drying heater to the
inside of the drum, a fan for forced supply of the hot air heated
by the drying heater to the inside of the drum, a hot air inlet at
a front side of the drum for supplying the hot air to the inside of
the drum, and a humid air recovery opening at a rear side of the
drum for recovering humid air from the inside of the drum.
[0028] In another aspect of the present invention, a drum washing
machine includes a tub for holding washing water, a drum rotatably
mounted in the tub, for introducing laundry therein, a drying
heater for heating air being supplied to an inside of the drum, a
drying duct forming a flow passage for supplying hot air heated by
the drying heater to the inside of the drum, a fan for forced
supply of the hot air heated by the drying heater to the inside of
the drum, a hot air inlet at a rear side of the drum for supplying
the hot air to the inside of the drum, and a humid air recovery
opening at a front side of the drum for recovering humid air from
the inside of the drum.
[0029] In another aspect of the present invention, a method for
controlling operation of a horizontal or tilt type drum washing
machine including a tub for holding washing water, a drum rotatably
mounted in the tub, for introducing laundry therein, a drum driving
motor for providing driving force to rotate the drum, a drying
heater for heating air being supplied to an inside of the drum, a
drying duct forming a flow passage for supplying hot air heated by
the drying heater to the inside of the drum, and a fan for forced
supply of the hot air heated by the drying heater to the inside of
the drum, the method including the step of supplying the hot air to
an inside of the drum while rotating the drum at a speed equal to,
or higher than a speed enough to keep the laundry in the drum to be
attached to, and not to fall off from, an inside surface of the
drum in progressing of a drying cycle.
[0030] In another aspect of the present invention, a method for
controlling operation of a horizontal or tilt type drum washing
machine including a tub for holding washing water, a drum rotatably
mounted in the tub, for introducing laundry therein, a drum driving
motor for providing driving force to rotate the drum, a drying
heater for heating air being supplied to an inside of the drum, a
drying duct forming a flow passage for supplying hot air heated by
the drying heater to the inside of the drum, and a fan for forced
supply of the hot air heated by the drying heater to the inside of
the drum, the method including the steps of turning off the drum
driving motor as spinning is finished, turning on the drying heater
and the fan, and supplying the hot air to an inside of the drum
while a rotation speed of the drum is maintained at a speed enough
to keep the laundry to be attached to, and not fall off from an
inside circumferential surface of the drum by turning on the drum
driving motor again before the laundry attached to the inside
circumferential surface of the drum in the spinning falls off
therefrom.
[0031] In another aspect of the present invention, a method for
controlling a drying cycle of a horizontal or tilt type drum
washing machine including a tub for holding washing water, a drum
rotatably mounted in the tub, for introducing laundry therein, a
drying heater for heating air being supplied to an inside of the
drum, a drying duct forming a flow passage for supplying hot air
heated by the drying heater to the inside of the drum, a fan for
forced supply of the hot air heated by the drying heater to the
inside of the drum, and means for determining dryness of the
laundry in the drum, the method including the steps of measuring
dryness of the laundry in the drum in a state the drum is
stationary after finish of spinning, supplying hot air while
rotating the drum at a speed equal to or higher than a speed enough
to keep the laundry to be attached to, and not to fall off from, an
inside surface of the drum by raising the rotating speed of the
drum, if measured dryness is below preset dryness, and supplying
the hot air to an inside of the drum while rotating the drum at a
speed below a speed enough to keep the laundry to be attached to,
and not to fall off from the inside surface of the drum, for
progressing drying, if the measured dryness is higher than the
preset dryness.
[0032] In another aspect of the present invention, a method for
controlling operation of a horizontal or tilt type drum washing
machine including a tub for holding washing water, a drum rotatably
mounted in the tub, for introducing laundry therein, a drying
heater for heating air being supplied to an inside of the drum, a
drying duct forming a flow passage for supplying hot air heated by
the drying heater to the inside of the drum, a fan for forced
supply of the hot air heated by the drying heater to the inside of
the drum, and means for determining dryness of the laundry in the
drum, the method including the steps of after spinning, supplying
the hot air to the inside of the drum while rotating the drum at a
speed to maintain a state in which the laundry is kept to be
attached to, and not to fall off from, but not to be attached
closely to, an inside surface of the drum, detecting the dryness in
the middle of above step, to progress drying while maintaining a
speed to maintain a state in which the laundry is kept to be
attached to, and not to fall off from, but not to be attached
closely to, the inside surface of the drum, if the dryness is below
a preset dryness, and progressing the drying after reducing the
rotation speed of the drum to a low speed at which the laundry is
unable to be attached to, but fall off from the inside surface of
the drum, if the dryness is higher than the preset dryness.
[0033] In another aspect of the present invention, a method for
controlling operation of a horizontal or tilt type drum washing
machine including a tub for holding washing water, a drum rotatably
mounted in the tub, for introducing laundry therein, a drying
heater for heating air being supplied to an inside of the drum, a
drying duct forming a flow passage for supplying hot air heated by
the drying heater to the inside of the drum, and a fan for forced
supply of the hot air heated by the drying heater to the inside of
the drum, and a hot air supply structure in which a hot air inlet
of the drying duct is positioned at a front side or a rear side of
the drum, and a humid air recovery opening of the drying duct is
positioned at the rear side or the front side of the drum opposite
to the hot air inlet, the method including the steps of, in
progressing a drying cycle, supplying hot air to an inside of the
drum through the hot air inlet positioned at a front, or a rear of
the drum, and, at the same time with this, rotating the drum at a
speed enough to keep the laundry attached to, and not fall off
from, but not to be attached closely to, an inside surface of the
drum, for progressing drying.
[0034] It is to be understood that both the foregoing general
description and the following detailed description of the present
invention are exemplary and explanatory and are intended to provide
further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this application, illustrate embodiment(s) of
the invention and together with the description serve to explain
the principle of the invention. In the drawings;
[0036] FIG. 1 illustrates a side section of a related art washing
and drying machine, schematically;
[0037] FIG. 2 illustrates a front section of the washing and drying
machine in FIG. 1;
[0038] FIG. 3 illustrates a diagram showing a main flow path of hot
air on an entrance side of a drum in a related art drum washing
machine, for reference;
[0039] FIG. 4 illustrates a drum washing machine of the present
invention showing a variation of hot air circulating structure;
[0040] FIG. 5 illustrates a drum washing machine of the present
invention showing another variation of hot air circulating
structure;
[0041] FIG. 6 illustrates a front view of a rear wall portion of a
tub cut along a I-I line in FIG. 5 for showing a through hole
structure in the tub;
[0042] FIG. 7 illustrates a flow chart showing the steps of a
method for controlling operation of a drum washing machine in
accordance with a first preferred embodiment of the present
invention;
[0043] FIG. 8 illustrates a flow chart showing the steps of a
method for controlling operation of a drum washing machine in
accordance with a second preferred embodiment of the present
invention;
[0044] FIG. 9 illustrates a flow chart showing the steps of a
method for controlling operation of a drum washing machine in
accordance with a third preferred embodiment of the present
invention;
[0045] FIG. 10 illustrates a flow chart showing the steps of a
method for controlling operation of a drum washing machine in
accordance with a fourth preferred embodiment of the present
invention; and
[0046] FIG. 11 illustrates a graph showing a rotation speed of a
motor for driving the drum, and turn on/off states of drying heater
and fan while drying.
DETAILED DESCRIPTION OF THE INVENTION
[0047] Reference will now be made in detail to the preferred
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings. Wherever possible, the
same reference numbers will be used throughout the drawings to
refer to the same or like parts.
[0048] Embodiments of the structure for supplying hot air in a drum
washing machine and an operation control method thereof will be
described, with reference to FIGS. 4 and 5.
[0049] A structure of a drum washing machine in accordance with a
first preferred embodiment of the present invention will be
described with reference to FIG. 4.
[0050] Referring to FIG. 4, the drum washing machine includes a tub
20 for holding washing water, a drum 30 rotatably mounted on an
inside of the tub 20, for introducing laundry therein, a drying
heater 61 for heating air being supplied to the inside of the drum
30, a drying duct 60 forming a flow passage for supplying hot air
heated by the drying heater 61, and fan 62 for forced supply of the
hot air heated by the drying heater 61 to the inside of the drum
30, wherein a hot air inlet 60a is positioned at a front of the
drum 30, and a humid air recovery opening 60b is positioned at a
rear of the drum 30.
[0051] More specifically, the hot air inlet 60a is positioned at
upper side of the front of the drum 30, and the humid air opening
60b is positioned at a lower side of the rear of the drum 30.
[0052] Meanwhile, even though FIG. 4 illustrates a horizontal type
drum washing machine, of course, the hot air supply and exhaust
structure is also applicable to the tilt type drum washing
machine.
[0053] A hot air circulating structure of the drum washing machine
will be described.
[0054] Referring to FIG. 4, in drying, the hot air is introduced
into the inside of the drum through an upper portion of the front
of the drum 30 by the forced air blow action of the fan 62, flows
from the front to a rear of the drum along a direction of the
arrow, passes a lower portion of a rear side of the drum, and is
introduced into the drying duct 60 through the humid air recovery
opening 60b in the rear wall of the tub 20.
[0055] A structure of a drum washing machine in accordance with a
second preferred embodiment of the present invention will be
described, with reference to FIG. 5.
[0056] Referring to FIG. 5, the drum washing machine includes a tub
20 for holding washing water, a drum 30 rotatably mounted on an
inside of the tub 20, for introducing laundry therein, a drying
heater 61 for heating air being supplied to the inside of the drum
30, a drying duct 60 forming a flow passage for supplying hot air
heated by the drying heater 61, and fan 62 for forced supply of the
hot air heated by the drying heater 61 to the inside of the drum
30, wherein a hot air inlet 60a is positioned at a rear of the drum
30, and a humid air recovery opening 60b is positioned at a front
of the drum 30.
[0057] More specifically, the hot air inlet 60a is positioned at an
upper side of the rear of the drum 30, and the humid air opening
60b is positioned at a lower side of the front of the drum 30.
[0058] It is preferable that there is a guide flow passage 21 at
the lower side of the tub 20 for guiding humid air from the humid
air recovery opening 60b at the lower side of the front of the drum
30 to the drying duct 60.
[0059] Meanwhile, even though FIG. 5 illustrates a tilt type drum
washing machine, of course, the hot air supply and exhaust
structure is also applicable to the horizontal type drum washing
machine.
[0060] A hot air circulating structure of the drum washing machine
will be described.
[0061] Referring to FIG. 5, in drying, the hot air is introduced
into the inside of the drum through an upper portion of the rear of
the drum 30 by the forced air blow action of the fan 62, flows from
the rear to a front of the drum along a direction of the arrow,
passes a lower portion of a front side of the drum, and flows
toward the humid air recovery opening 60b of the drying duct 60
along the guide flow passage 21 in the lower side of the tub
20.
[0062] In the meantime, the drum type washing machine in accordance
with a second preferred embodiment of the present invention, the
tub 20 is formed of stainless steel, or plastic. Regardless of
material of the tub 20, in the rear wall of the tub, there are the
hot air inlet 60a for supplying hot air, and a hot air outlet 60c
for discharge of the hot air (see FIG. 6).
[0063] It is favorable that the hot air inlet 60a and the hot air
outlet 60c each has a shape of slot, especially in a shape of an
arc in view of strength of the tub rear wall, and connected to the
drying duct 60, directly.
[0064] Meanwhile, alike the related art drum, the drum of the
present invention has a plurality of pass through holes in an
outside circumferential surface of the drum, which are not shown in
the drawings.
[0065] Next, the steps of an operation control method in accordance
with embodiments of the present invention will be described with
reference to FIGS. 7.about.11. First, referring to FIG. 7, an
operation control method in accordance with a first preferred
embodiment of the present invention will be described.
[0066] In a drying cycle, while rotating the drum at a speed equal
to or higher than a speed (for an example, 100 rpm) enough to keep
the laundry to be attached to, and not to fall from, but not to be
attached closely to, the inside surface of the drum, the hot air is
supplied to an inside of the drum, for progressing drying.
[0067] The speed enough to keep the laundry to be attached to, and
not to fall off from, but not to be attached closely to the inside
surface of the drum, is a speed at which an outward acceleration
acting on a point of an inside circumferential surface of the drum
in a radial direction of the drum is equal to an acceleration of
the gravity.
[0068] In the meantime, the hot air supplied to the inside of the
drum flows in a direction along a driving shaft of the drum. That
is, the hot air flows from the hot air inlet 60a (see FIG. 4) in
the front of the drum to the rear of the drum, or from the hot air
inlet 60a (see FIG. 5) to the front of the drum. For this, it is
preferable that the hot air is supplied from the upper side of the
front of the drum to the lower side of the rear of the drum, or
from the upper side of the rear of the drum to the lower side of
the front of the drum.
[0069] According to this, in the embodiment, if the hot air is
supplied in the driving shaft direction of the drum in a state the
drum rotates at the speed enough to keep the laundry to be attached
to, and not to fall off from an inside surface of the drum, the hot
air progresses along the driving shaft direction while swirling
along the inside circumferential surface of the drum.
[0070] That is, the hot air progresses in a form of a swirl
starting from the front side of the drum to the rear side of the
drum until the hot air escapes therefrom, or the hot air progresses
in a form of a swirl starting from the rear side of the drum to the
front side of the drum until the hot air escapes therefrom.
According to this, contact of the hot air with the laundry on the
inside circumferential surface of the drum increases, to enhance
the drying performance, and efficiency.
[0071] In the meantime, it is preferable that the drying cycle
progressed thus includes an acceleration section in which the motor
for driving the drum is turned on, to accelerate a rotation speed
of the drum until the rotation speed reaches to a preset speed
which is equal to, or higher than a speed enough to keep the
laundry in the drum to be attached to, and not to fall off from the
inside surface of the drum, a section for maintaining the rotation
speed at the preset speed, and a section in which the rotation
speed of the drum is reduced to a low speed (about 20.about.30 rpm)
at which the laundry in the drum is unable to be attached to, but
to fall from the inside surface of the drum, for progressing
drying.
[0072] It is more preferable that above acceleration, maintained
speed, and low speed sections are performed at least once
repeatedly before finish of the drying. This is for enhancing the
drying efficiency by keeping exposing portions of the laundry that
are not dried yet by changing positions of the laundry.
[0073] It is meantime, it is preferable that a rotation direction
of the drum is alternated in the section drying is progressed in a
low speed state in which the laundry falls from the inside surface
of the drum.
[0074] Next, referring to FIG. 8, an operation control method in
accordance with a second preferred embodiment of the present
invention will be described.
[0075] The method for controlling drying laundry in a horizontal,
or tilted type drum washing machine in accordance with the second
preferred embodiment of the present invention includes the steps of
turning off a drum driving motor as spinning is finished, turning
on a drying heater and a fan, and turning on the drum driving motor
again before the laundry kept attached to an inside circumferential
surface of the drum at the time of spinning falls to maintain a
threshold speed enough to keep the laundry to be attached to the
inside circumferential surface of the drum and supplying heated air
into an inside of the drum, to progress drying.
[0076] That is, in the embodiment, after turning off the driving
motor, hot air is supplied while maintaining the drum at a speed
higher than the threshold speed at which the laundry kept attached
to the inside circumferential surface of the drum does not fall by
turning on the drum driving motor again before the speed of the
drum rotating by inertia drops to a speed at which the laundry kept
attached to the inside circumferential surface of the drum
falls.
[0077] In this instance, the drying heater and the fan may be
turned on at the same time with turning off the drum driving motor
when the spinning is finished, or the drying heater and the fan may
be turned on after a predetermined time period is passed from the
turning off of the drum driving motor. In this instance, no braking
force is applied to the drum, so that the drum spinning in a state
the drum driving motor is turned off as the spinning is finished
rotates freely by the inertia. The drying heater and the fan may,
or may not be turned on at the same time.
[0078] The hot air flows along a direction of a drum driving shaft
line in the drum, for which it is preferable that the hot air is
supplied from a front to a rear of the drum, or vice versa, like
the first embodiment.
[0079] Alike the first embodiment, the dry progressing step may
include a section in which the rotation speed of the drum is
maintained at a speed equal to, or higher than a speed (for an
example, 100 rpm) enough to keep the laundry in the drum to be
attached to, and not to fall off from, but not to be attached
closely to, the inside circumferential surface of the drum, and a
section in which the rotation speed of the drum is reduced to a low
speed (about 20.about.30 rpm) at which the laundry in the drum is
unable to be attached to the inside circumferential surface of the
drum.
[0080] Thus, the embodiment enables to reduce a drying time period
as the drying heater and the fan are turned on starting from the
inertial rotation of the drum following finishing of spinning to
supply hot air, and drying laundry starting from right after the
finishing of spinning, and to improve drying efficiency and
performance as the rotation speed of the drum is maintained at a
speed higher than the speed enough to keep the laundry in the drum
to be attached to the inside circumferential surface of the drum,
to make the hot air to progress in a form of a swirl like the first
embodiment.
[0081] Next, a method for controlling operation of a drum washing
machine in accordance with a third preferred embodiment of the
present invention will be described with reference to FIG. 9.
[0082] If the drum washing machine of the first or second
embodiment is further provided with means in the drum 30 for
determining dryness (for an example, an electrode sensor: not
shown) of the laundry, the following operation control method is
also viable.
[0083] That is, a method for controlling operation of a horizontal
or tilt drum washing machine in accordance with a third preferred
embodiment of the present invention includes the steps of measuring
dryness of laundry in the drum in a state the drum is stationary
after finish of spinning, supplying hot air to an inside of the
drum while rotating the drum at a speed equal to or higher than a
speed at which an outward acceleration acting on a point of an
inside circumferential surface of the drum in a radial direction of
the drum is equal to an acceleration of the gravity if the dryness
measured in above step is below a preset dryness, and supplying hot
air to an inside of the drum while rotating the drum at a reduced
speed at which the laundry is unable to be attached to the inside
surface of the drum if the dryness measured in above step is higher
than the preset dryness, for drying.
[0084] Meanwhile, though it is preferable that the measurement of
dryness is performed in a state the drum is stopped fully after the
finish of spinning, the dryness may be measured in a state before
the drum is stopped fully after the finish of spinning.
[0085] Moreover, in the embodiment too, the hot air flows in a
direction the same or substantially same with a drum driving shaft
in the drum. Especially, it is preferable that the hot air flows
from a front to a rear of the drum, or vice versa.
[0086] Alike embodiments described before, in the embodiment too,
it is preferable that a rotation direction of the drum is
alternated in the section drying is progressed in a reduced speed
state to a speed (about 20.about.30 rpm) at which the laundry falls
from the inside surface of the drum.
[0087] Next, a method for controlling operation of a drum washing
machine in accordance with a fourth preferred embodiment of the
present invention will be described, with reference to FIG. 10.
[0088] A method for controlling drying operation of a horizontal,
or tilt type drum washing machine in accordance with a fourth
preferred embodiment of the present invention includes the steps
of, after finish of spinning, supplying hot air to an inside of the
drum while rotating the drum at a speed equal to, or higher than a
speed (for an example, 100 rpm) enough to keep the laundry to be
attached to, and not to be fall off from an inside surface of the
drum, and progressing the drying while maintaining a threshold
speed which is a speed enough to keep the laundry to be attached
to, and not to fall off from, an inside surface of the drum if the
dryness detected in the middle of above step is below preset
dryness, and progressing the drying in a reduced speed state to a
speed (about 20.about.30 rpm) at which the laundry falls off from
the inside surface of the drum if the dryness is higher than the
preset dryness.
[0089] That is, in the embodiment, the dryness is measured in a
state the drum is rotated at a speed higher than a speed enough to
keep the laundry to be attached to the inside circumferential
surface of the drum, and the speed of the drum is controlled to
maintain, or reduce according to a result of the measurement. This
is because an accurate measurement of dryness is possible the same
with a case when the drum is stationary as there is no position
change of the laundry at the speed at which the laundry does not
fall off from, but is kept attached to, the inside circumferential
surface of the drum.
[0090] In the meantime, in the embodiment too, the hot air flows in
a direction the same with a drum driving shaft in a drum.
Especially, alike foregoing embodiments, it is preferable that the
hot air flows from a front to a rear of the drum, or vice
versa.
[0091] Alike the foregoing embodiments, a rotation direction of the
drum is alternated in the section the drying is progress in a
reduced speed state to a speed (about 20.about.30 rpm) at which the
laundry in the drum falls off the inside surface of the drum.
[0092] Thus, the embodiment enables to reduce a drying time period
as the hot air is supplied to an inside of the drum starting from
the inertial rotation of the drum following finishing of spinning,
to progress drying, and to improve drying performance and
efficiency as the rotation speed of the drum is maintained at a
speed equal to, or higher than a speed enough to keep laundry not
to fall off from the inside circumferential surface of the drum so
that the hot air progresses while swirling at a dryness below a
preset dryness.
[0093] If the measured dryness is higher than the preset dryness,
the rotation speed of the drum is reduced, to change positions of
the laundry, in which the a rotation direction of the drum is
alternated, for changing positions of the laundry. According to
this, portions of laundry dried less than other portions are
exposed newly, to which the hot air comes into contact, to dry the
less dried portions.
[0094] In the meantime, after the reduced speed state is over, the
rotation speed of the drum rises again until the laundry is
attached to the inside circumferential surface of the drum, when
the dryness is detected again. According to this, above drying
control process is repeated.
[0095] In the method for controlling drying operation in accordance
with any one embodiments of the present invention, a portion of the
clothes is liable to be inserted in the holes in the wall of the
drum if the rotation speed of the drum is high excessively.
Moreover, the clothes is liable be inserted in the holes in the
wall of the drum, to make circulation of the clothes difficult if
the drying time period is long excessively even if the rotation
speed of the drum is not so high excessively, but only is
maintained at a speed (for an example; 100 rpm) enough to keep the
laundry to be attached to an inside of the drum.
[0096] Therefore, in each of the embodiments, it can be known it is
preferable in view of clothes circulation that a section for
progressing drying at a speed in which the laundry can not be
attached to, but fall off from the inside surface of the drum in a
state the drying heater and the fan are turned on, a section in
which the drum driving motor is turned on to accelerate the drum to
a speed higher than a speed enough to keep the laundry to be
attached to, and not to fall off from the inside surface of the
drum, and a section in which the rotation speed of the drum is
maintained at a speed enough to keep the laundry to be attached to,
and not to fall off from the inside surface of the drum, are
mixed.
[0097] In the method for controlling drying operation in accordance
with the third or fourth preferred embodiment of the present
invention, a drying finish time point can be determined as
follows.
[0098] The finish of drying may be simply set to finish the drying
at the time the set time is reached. Or alternatively, the drying
may be finished by setting a drying time period, measuring the
dryness when the set drying time period is reached, and extending
the drying time period according to the measured dryness. Or
alternatively, regardless of a set drying time period, the finish
of drying may be determined with reference to a preset dryness
which is different from the set dryness in the third or fourth
embodiment.
[0099] FIG. 11 illustrates a graph showing a rotation speed of a
motor for driving the drum, and turn on/off states of drying heater
and fan while drying.
[0100] Referring to FIG. 8, it can be known that a section for
progressing drying at a speed in which the laundry can not be
attached to, but fall off from the inside surface of the drum in a
state the drying heater and the fan are turned on, a section in
which the drum driving motor is turned on to accelerate the drum to
a speed higher than a speed enough to keep the, laundry to be
attached to, and not to fall off from the inside surface of the
drum, and a section in which the rotation speed of the drum is
maintained at a speed enough to keep the laundry to be attached to,
and not to fall off from the inside surface of the drum, are
mixed.
[0101] Of course, a rotation direction of the drum can be
alternated in the section in which the rotation speed of the drum
is low (about 20.about.30 rpm).
[0102] As has been described, the structure for supplying hot air
in a drum washing machine and operation control method thereof has
the following advantages.
[0103] The uniform introduction of hot air into the inside of the
drum through out the drum enhances drying performance and
efficiency.
[0104] That is, the introduction of hot air starting from a front
to a rear or vice versa deep into the drum improves drying
efficiency and performance. Especially, because the rotation speed
of the drum is maintained at a speed enough to keep laundry not to
fall off from the inside circumferential surface of the drum, such
that the hot air comes into contact with the laundry while
progressing in swirl, the drying performance and efficiency is
improved.
[0105] The supply of hot air to the inside of the drum starting
from the inertial rotation of the drum following finish of spinning
enables to shorten a drying time period.
[0106] The alteration of the rotation direction of the drum in the
section the dry is progressed at a low speed, to keep surfaces in
contact with the hot air changing, permits to improve the drying
efficiency, and the swirling of the hot air further improves the
drying performance owing to the position changes of the
laundry.
[0107] It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the spirit or scope of the inventions. Thus,
it is intended that the present invention covers the modifications
and variations of this invention provided they come within the
scope of the appended claims and their equivalents.
* * * * *