Note: Descriptions are shown in the official language in which they were submitted.
CA 02721187 2010-10-12
WO 2009/128603 PCT/KR2009/000188
Description
CONTROLLING METHOD OF WASHING MACHINE
Technical Field
[1] The present invention relates to a controlling method of a washing
machine. More
particularly, the present invention relates to a controlling method of a
washing machine
to reduce an overall washing time with an improved rinsing efficiency.
Background Art
[2] Washing machines are home electric appliances that remove dirt from
washing
objects including clothes, cloth items, beddings and the like (hereinafter,
laundry)
through a washing, rinsing and spinning cycle. Such washing machines may be
cat-
egorized, based on how to load laundry, into top loading types and front
loading types.
The top loading type washing machines may be categorized into drum types and
pulsator types. In a drum type, a drum is rotated during the washing and
rinsing cycle.
In a pulsator type, a pulsator is provided in a tub and the pulsator is
rotated.
[3] The front loading type and the top loading type drum washing machine
include a
cabinet, a tub and a drum. The cabinet defines an exterior appearance of the
washing
machine. The tub is provided in the cabinet and it holds wash liquid. The drum
is
rotatable and it is provided in the tub. Laundry is held in the drum. As the
drum or
pulsator is rotated horizontally or vertically, the washing, rinsing and
spinning cycle
may be performed.
[4] However, if the drum is rotated at a relatively high speed with the
laundry loaded in
the drum, the laundry might be collected in a side of the drum. As a result, a
large
vibration might be generated and a predetermined process is necessary to
spread the
laundry inside the drum uniformly. The process is especially necessary in the
rinsing
cycle because water should be supplied repeatedly to remove detergent in the
rinsing
cycle.
[5] Accordingly, it takes a substantially long time to spread the laundry
uniformly in an
overall washing course of a conventional washing machine, especially, in the
rinsing
cycle of the washing course.
Disclosure of Invention
Technical Problem
[6] However, if the drum is rotated at a relatively high speed with the
laundry loaded in
the drum, the laundry might be collected in a side of the drum. As a result, a
large
vibration might be generated and a predetermined process is necessary to
spread the
laundry inside the drum uniformly. The process is especially necessary in the
rinsing
cycle because water should be supplied repeatedly to remove detergent in the
rinsing
2
WO 2009/128603 PCT/KR2009/000188
cycle.
[7] Accordingly, it takes a substantially long time to spread the laundry
uniformly in an
overall washing course of a conventional washing machine, especially, in the
rinsing
cycle of the washing course.
Technical Solution
[8] Accordingly, the present invention is directed to a controlling method of
a washing
machine.
[9] In one aspect, a controlling method is provided to reduce a time of a
rinsing cycle.
[10] In another aspect, a controlling method of a washing machine is provided
to improve
rinsing efficiency as well as to reduce the time of the rinsing cycle.
[11] Additional advantages, objects, and features of the disclosure 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.
[12] To achieve these objects and other advantages and in accordance with the
purpose of
the invention, as embodied and broadly described herein, a controlling method
of a
washing machine may include spinning to rotate a drum at a first speed to
extract water
from the laundry; water draining to drain water from the drum; water supplying
to
supply water to a tub, while rotating the drum at a second speed for the
laundry to be
closely in contact with an inner circumferential surface of the drum; and
penetration
rinsing while rotating the drum at a third speed to rinse the laundry.
[13] In the spinning operation, the first speed may be more than 600 rpm to
dehydrate,
i.e., drain water from, the laundry.
[14] In the water draining operation, the rotation speed of the drum may be
reduced. Es-
pecially, it is preferable that in the water draining operation, the rotation
speed of the
drum is reduced to a predetermined speed that is higher than a minimum drum
speed at
which the laundry is closely in contact with the inner circumferential surface
of the
drum.
[15] In the water supplying operation, the second speed may be higher than a
minimum
drum speed at which the laundry is closely in contact with the inner
circumferential
surface of the drum. It is preferable that in the water supplying operation,
water is
supplied to a predetermined depth lower than a distance between the tub and
the drum.
[16] In the penetration rinsing operation, water held in the tub may be
circulated during
the rotation of the drum. Here, in the penetration rinsing operation, the
circulated water
may be supplied in at least one of a horizontal direction and a vertical
direction along
CA 02721187 2010-10-12
3
WO 2009/128603 PCT/KR2009/000188
an inside of the drum.
[17] The third speed may be lower than the first speed and higher than the
second speed.
Specifically, in the penetration rinsing operation, the drum may be rotated at
the third
speed such that the circulated water is penetrated through the laundry that is
closely in
contact with the inner circumferential surface of the drum to perform rinsing.
[18] The controlling method may further include at least one tumbling rinsing
operation
after the spinning operation the water draining operation, the water supplying
operation, and the penetration rinsing operation are performed repeatedly a
plurality of
times.
[19] 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.
Advantageous Effects
[20] 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
invention. 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.
Brief Description of Drawings
[21] The accompanying drawings, which are included to provide a further
understanding
of the disclosure and are incorporated in and constitute a part of this
application, il-
lustrate embodiment(s) of the disclosure and together with the description
serve to
explain the principle of the disclosure. In the drawings:
[22] FIG. 1 is a perspective view illustrating a washing machine having a
controlling
method of an exemplary embodiment applied thereto;
[23] FIG. 2 is a flow chart of the controlling method;
[24] FIG. 3 is a graph illustrating a rotation speed of a drum of a washing
machine
according to an exemplary embodiment;
[25] FIG. 4 is a graph illustrating a rotation speed of a drum of a washing
machine
according to another embodiment; and
[26] FIG. 5 is a perspective view illustrating a nozzle to supply wash water
circulated in
FIG. 1.
Best Mode for Carrying out the Invention
[27] Reference will now be made in detail to the specific 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.
CA 02721187 2010-10-12
4
WO 2009/128603 PCT/KR2009/000188
[281 A washing machine having a controlling method according to an exemplary
em-
bodiment applied thereto will be explained first and the controlling method
will be
explained next.
[291 FIG. 1 is a perspective view illustrating a washing machine to which a
controlling
method according to an exemplary embodiment is applied. FIG. 1 shows a front
loading type washing machine. However, the controlling method according to the
em-
bodiment can be applied to a top loading type drum washing machine as well as
the
front loading type drum washing machine. The embodiment will be explained with
reference to the front loading type drum washing machine.
[301 In reference to FIG. 1, the washing machine includes a cabinet 10, a tub
(not shown)
and a drum 20. The cabinet 10 defines an exterior appearance of the washing
machine.
The tub (not shown) is provided in the cabinet 10 and the drum 20 is rotatably
provided in the tub.
[311 Wash water is held in the tub and laundry may be loaded through a door 12
coupled
to a front of the cabinet 10. The drum 20 may be rotated by driving means (not
shown)
including a motor. As the drum 20 is rotated, a washing, rinsing and spinning
cycle
may be performed.
[321 An operational part 14 may be provided on a front surface of the cabinet
10 to
control an operation of the washing machine and to display a state of the
washing
machine. Because of the operational part 14, a user can control the operation
of the
washing machine and recognize a state of the washing machine.
[331 The washing machine may be configured to provide a washing course
including a
washing and rinsing and spinning cycle. A washing machine having a drying
function
may be further configured to provide a drying course. In the washing cycle,
water is
primarily supplied to the drum 20 and the drum 20 is rotated in a clockwise
and
counter-clockwise direction to perform washing. In the rinsing cycle, the
laundry is de-
hydrated and the drum 20 is rotated to rinse the laundry. In the spinning
cycle, the
drum 20 is rotated at a high speed and the laundry is spun to dehydrate the
laundry.
[341 In the rinsing cycle, water is again supplied and the drum 20 is rotated
to remove
detergent from the laundry. This results in taking quite a long time. That is,
in the con-
ventional washing machine, during the water supply operation, the drum 20
stops
rotating and the laundry may drop to a lower portion of the drum.
[351 Hence, if the drum 20 is re-rotated after the water supply, laundry may
not be spread
uniformly in the drum 20 and thus a process of spreading the laundry should
addi-
tionally be performed. For example, the drum 20 is repeatedly rotated in a
clockwise
direction and counter-clockwise direction at a predetermined speed to
uniformly spread
the laundry in the drum 20. After that, the drum 20 is re-rotated to perform a
rinsing
cycle. As a result, a lot of time is required for a rinsing cycle, because the
process of
CA 02721187 2010-10-12
5
WO 2009/128603 PCT/KR2009/000188
spreading laundry should be performed every time in the water supply operation
of the
rinsing cycle. This can be quite inconvenient to a user.
[36] The controlling method of a washing machine according to the embodiment
tries to
solve that and it is developed to improve rinsing efficiency. Next, the
controlling
method of an exemplary embodiment will be explained with reference to the
drawings.
[37] FIG. 2 is a flow chart of the controlling method according to an
exemplary em-
bodiment and FIG. 3 is a graph illustrating a rotation speed of the drum 20 in
the con-
trolling method.
[38] With reference to FIGS. 2 and 3, the controlling method of the embodiment
relates to
a rinsing cycle that may be included in a washing course of a washing machine
or a
rinsing cycle that may be performed independently from other cycles.
[39] The controlling method includes spinning (S210), water draining (S230),
water
supplying (S250) and rinsing (S270). In the spinning step (S210), the laundry
is spun
to dehydrate the laundry. In the water draining step (S230), water of the drum
20 is
drained. In the water supplying step (S250), water is supplied to the tub, and
the drum
20 is rotated so that the laundry is not spaced apart from an inner
circumferential
surface of the drum 20, in other words, for the laundry to be closely in
contact with an
inner circumferential surface of the drum 20. In the penetration rinsing step
(S270), the
laundry is rinsed. That is, in the controlling method of the embodiment, the
drum 20 is
rotated in a case where water is supplied to the tub. Especially, the drum 20
is rotated
at a predetermined speed higher than a minimum drum speed at which the laundry
is
not spaced apart from the inner circumferential surface of the drum 20. As a
result, a
process of spreading the laundry uniformly may not be needed after the water
supply
operation.
[40] First of all, according to the controlling method of the embodiment, the
drum 20 is
rotated at a first speed to dehydrate the laundry (S210). Commonly, the
rinsing cycle is
performed after the washing cycle and it is preferable that the laundry is
dehydrated
prior to the rinsing cycle.
[41] In this spinning step (S210), the drum 20 is rotated at the first speed
to dehydrate the
laundry. The first speed may be adjustable according to a capacity of the
washing
machine and an amount of the laundry. For example, the first speed may be ap-
proximately 600 rpm. In the spinning step of the controlling method according
to the
embodiment, the drum 20 is rotated at the first speed, for example, more than
600 rpm
to dehydrate the laundry.
[42] More specifically, in the spinning step as shown in FIG. 3, the rotation
speed of the
drum 20 is increased until the first speed is reached. Hence, if the rotation
speed of the
drum 20 reaches the first speed, the rotation speed may be reduced immediately
and it
is preferable that the rotation speed of the drum 20 is maintained at the
first speed
CA 02721187 2010-10-12
6
WO 2009/128603 PCT/KR2009/000188
during a predetermined time period, for example, 2 to 5 seconds. Maintaining
the
rotation speed of the drum 20 at the first speed makes it possible to
dehydrate the
laundry easily.
[43] After dehydrating the laundry, water in the tub 10 may be drained (S230).
The
removed moisture of the laundry in the spinning step is stored in the tub and
thus it is
necessary to drain the water held in the tub.
[44] As shown in FIG. 3, the water of the tub is drained and it is preferable
that the water
in the tub is drained as the rotation speed of the drum 20 is reduced. If the
drum 20 is
rotated at a relatively high speed, the water of the tub may not be drained
because of
the high speed rotation of the drum 20. As a result, if the water is drained
as the
rotation speed of the drum 20 is reduced, it is possible to easily drain the
water in the
tub.
[45] Although the rotation speed of the drum 20 is reduced in the water
draining step, it is
preferable that the laundry is closely in contact with the inner
circumferential surface
of the drum 20. That is, if the laundry is spaced apart and dropped from the
inner cir-
cumferential surface of the drum 20, a process of spreading the laundry in the
drum 20
uniformly should be performed after the water supplying step which will be
described
later and an overall time of the rinsing cycle is increased accordingly.
[46] Thus, in the water draining step according to the controlling method of
the em-
bodiment, the rotation speed of the drum 20 is reduced until a predetermined
speed
higher than the minimum drum speed at which the laundry is closely in contact
with
the inner circumferential surface of the drum 20. This minimum drum speed may
be
adjustable according to a capacity of a washing machine, a capacity of a drum
and an
amount of loaded laundry. In this embodiment, it is not limited to a specific
number,
but the minimum drum speed of this embodiment may be, for example,
approximately
100 to 110 rpm.
[47] In other words, the rotation speed of the drum 20 is reduced until a
predetermined
speed higher than the minimum drum speed, for example, 100-110 rpm, during the
water draining operation of the tub.
[48] According to the embodiment of the controlling method, water is supplied
to the tub
after the water draining step. Specifically, the water is supplied to the tub
while
rotating the drum 20 at a second speed so that the laundry is not spaced apart
from the
inner circumferential surface of the drum 20 (S250).
[49] That is, after the water of the tub is drained, water is supplied to the
tub to rinse the
laundry. In this case, according to the embodiment of the controlling method,
the drum
20 is not stopped, but instead is rotated at the second speed during the water
supplying
operation. It is preferable that the drum 20 is rotated at a predetermined
speed higher
than the minimum drum speed at which the laundry is closely in contact with
the inner
CA 02721187 2010-10-12
7
WO 2009/128603 PCT/KR2009/000188
circumferential surface of the drum 20, in other words, the laundry is not
spaced apart
from the inner circumferential surface of the drum 20.
[501 As mentioned above, in order not to perform an additional process of
spreading the
laundry in the drum 20 uniformly, also in the water supplying step, the water
is
supplied as the drum 20 is rotated at a predetermined speed higher than the
minimum
drum speed at which the laundry is not spaced apart from the inner
circumferential
surface of the drum 20 after the water supplying step. The minimum drum speed
may
be, for example, 100 - 110 rpm, which is a relatively low speed, but is enough
to
perform the water supplying step smoothly. At this time, the drum 20 is
repeatedly
rotated and the laundry is closely in contact with the inner circumferential
surface of
the drum 20 by centrifugal force. As a result, the rinsing process may start
immediately
without performing an additional process of spreading the laundry uniformly in
the
drum 20 after the water supplying step.
[511 In the water supplying step of the embodiment, in case of supplying
water, the water
may be supplied to a level lower than a distance between the tub and the drum
20. That
is, if the water is supplied to the tub, a level of the water held in the tub
may not be
increased over the drum 20 and it is preferable that the level of the water
held in the
tub may not reach the drum 20.
[521 As mentioned above, the drum 20 is rotated during the water supplying
step. If the
level of the water is over the drum 20, the rotation of the drum 20 may not be
performed smoothly because of the friction between the drum 20 and the water.
In
addition, if the controlling method according to the embodiment includes the
pen-
etration rinsing step, the drum 20 is rotated at a relatively high speed. As a
result, it is
preferable that the water is supplied to the level high enough not to reach
the drum 20
in order to avoid the friction between the drum 20 rotating at the high speed.
[531 According to the controlling method of the embodiment, after the water
supplying
step, the drum 20 is rotated at the second speed like in the water supplying
step to
perform rinsing (S270).
[541 Specifically, according to an embodiment, the rinsing (S270) is performed
by
rotating the drum 20 at the same rotation speed as the speed of the water
supplying
step, namely, the second speed.
[551 Specifically, the second rotation speed of the water supplying step is
higher than the
minimum drum speed at which the laundry is not spaced apart from the inner
circum-
ferential surface of the drum 20. Thus, if the drum 20 is rotated repeatedly
at the
second speed, the laundry may not be spaced apart from the inner
circumferential
surface of the drum 20 during both the water supplying step and the rinsing
step. As a
result, it is possible to reduce the rinsing time remarkably. Thus, in this
embodiment,
the water supplying step is performed while rotating the drum 20 at the second
rotation
CA 02721187 2010-10-12
8
WO 2009/128603 PCT/KR2009/000188
speed. After the water supplying step, the rinsing step starts.
[56] Here, when the rinsing step (S270) is performed in this embodiment,
'penetration
rinsing' may be performed with rotating the drum at the second speed. The term
'pen-
etration rinsing' means that rinsing is performed while rotating the drum 20
at a speed
at which the laundry is in close contact with the inner circumferential
surface of the
drum 20, different from the conventional rotation speed of the rinsing. In
this case, the
water of the laundry is penetrated through the laundry by centrifugal force
and it is
discharged out of the drum 20 to perform rinsing.
[57] This penetration rinsing step is performed by rotating the drum 20, with
the water
held in a lower portion of the tub being circulated to an upper portion of the
tub. If the
water level may not reach the drum 20 during the water supplying as mentioned
above,
an amount of the water may be insufficient during the penetration rinsing
step. As a
result, the water held in the lower portion of the tub is circulated to the
upper portion
and the water is re-supplied to the drum 20 in the penetration rinsing step.
As a result,
the rinsing may be performed more smoothly.
[58] Although not shown in the drawings, the washing machine having the
controlling
method applied thereto may include a circulation unit configured to circulate
wash
water. The circulation unit may include a circulation line and a circulation
pump. The
lower portion of the tub is connected with the upper portion of the tub by the
cir-
culation line. The circulation pump is configured to circulate the wash water
to the
upper portion of the tub along the circulation line. Thus, it is possible to
supply the
water held in the lower portion of the tub to the inside of the drum 20 again
via the
upper portion of the tub along the circulation line by using the circulation
pump. In this
case, a nozzle may be provided at an end of the circulation line connected
with the
upper portion of the tub to spray the water. The nozzle to supply the
circulated wash
water may be provided in the upper portion of the tub, preferably, in an upper
front
portion of the tub.
[59] In this case of supplying the wash water via the nozzle, the nozzle is
provided at the
upper front portion of the tub and the wash water might be supplied mainly to
a front
portion of the drum 20. Especially, the wash water sprayed via the nozzle at a
prede-
termined water pressure may be supplied to the front portion of the drum 20 in
a
horizontal direction. This might cause a problem that the wash water is
supplied only
to some of the laundry put in the front portion of the drum 20 and not to the
other
laundry put in a rear portion of the drum 20.
[60] Thus, it is preferable that the wash water is supplied in at least one of
a horizontal
direction and a vertical direction along the inside of the drum 20 when the
wash water
is circulated in the rinsing step.
[61] Then, it is possible to supply the wash water in a horizontal direction
along the inside
CA 02721187 2010-10-12
9
WO 2009/128603 PCT/KR2009/000188
of the drum 20 by using the conventional nozzle. To supply the wash water
along a
vertical direction of the inside of the drum, an auxiliary configuration is
necessary to
supply the wash water to plural spots along a vertical direction inside the
drum 20.
[62] FIG. 5 is a perspective view illustrating a circulation nozzle configured
to supply the
wash water along a vertical direction of the drum inside of the washing
machine.
[63] In reference to FIG. 5, the circulation nozzle 100 may be formed to spray
the wash
water to a rear portion as well as a front portion of the drum 20 along a
vertical
direction. The circulation nozzle 100 may be formed to spray the wash water
along
plural directions of the drum interior so that the wash water may be uniformly
supplied
to the laundry in the drum 20.
[64] As a result, the circulation nozzle 100 may include plural spray holes
110 directed
toward the drum interior. Each of the spray holes 110 may be formed to spray
the wash
water to a different drop position along a vertical direction of the drum 20.
That is, the
spray holes 110 may be configured to spray the wash water to different
positions
spaced apart a predetermined distance from the front portion to the rear
portion of the
drum 20, respectively. As a result, the wash water is uniformly supplied to
the laundry
inside the drum 20 regardless of the rotation of the drum 20.
[65] On the other hand, the circulation nozzle 100 may be installed at a front
portion of
the drum 20 where an opening of the drum 20 is formed. In this case, it is
preferable
that a spraying direction or spraying speed of the wash water sprayed through
each of
the spray holes 110 may be different from each other so that the wash water
may be
sprayed to different positions from the front portion to the rear portion of
the drum 20
via the spray holes 110, respectively. At this time, it is preferable that
each of the spray
holes 100 formed at the circulation nozzle 100 includes different cross
sections or
different paths, respectively.
[66] Specifically, a cross section of each spray hole 110 of the circulation
nozzle 100 is
different from each other to make the pressure of the wash water sprayed via
each of
the spray holes 110 different from each other. Here, as the cross section of
the spray
hole 110 is smaller, the pressure of the wash water is higher and as the cross
section is
larger, the pressure of the wash water is lower. As a result, the wash water
sprayed via
the spray hole 110 having a larger cross section at a lower pressure is
dropped im-
mediately, whereas the wash water sprayed via the spray hole 110 having a
smaller
cross section at a higher pressure is sprayed further in a spraying direction.
[67] The spray hole 110 having the larger cross section may be formed to
supply the wash
water to the front portion of the drum 20 and the spray hole 110 having the
smaller
cross section may be formed to supply the wash water to the rear portion of
the drum
20.
[68] Specifically, the spray holes 110 formed along direction 'a' may have a
relatively
CA 02721187 2010-10-12
10
WO 2009/128603 PCT/KR2009/000188
smaller cross sections, and the spray holes 110 formed along direction 'b' may
have a
relatively larger cross sections. As a result, the wash water may be sprayed
at a
relatively higher pressure via the spray holes 110 formed along direction 'a'
and the
wash water may be sprayed at a relatively lower pressure via the spray holes
110
formed along direction V.
[69] Furthermore, the spray holes 110 of the circulation nozzle 100 may be
connected
with paths 120 formed differently from each other, respectively. It may be
possible to
differentiate a speed of the wash water sprayed via each of the spray holes
110 of the
circulation nozzle 100.
[70] That is, the circulation nozzle 100 may include plural paths 120 and the
wash water
drawn from the circulation unit 40 passes through the paths 120. Each of the
paths 120
may be formed corresponding to each of the plural spray holes 110 such that
the wash
water having passed through each of the paths 120 may be sprayed with a
different
speed.
[71] For example, the wash water having passed through the path 120 formed in
a vertical
direction is dropped in the front portion of the drum 20, and the wash water
having
passed through the path 120 extended in a horizontal direction toward the drum
interior
is sprayed to the rear portion of the drum 20 because it has a speed element
toward the
drum interior. As a result, the wash water may be supplied to the rear portion
in the
drum 20 along a horizontal direction via the spray holes 110 connected with
the paths
120 extended in a horizontal direction toward the drum interior. It is
possible to ad-
justably drop the wash water at different spots in the drum 20 according to
the nozzle
speed of the wash water.
[72] As shown in FIG. 5, for example, the paths 120 connected with the spray
holes 110
formed along direction 'a' may be extended horizontally toward the drum
inside. The
paths 120 connected with the spray holes 110 formed along direction 'b' may be
extended relatively short toward the drum interior. Here, it is possible that
a portion of
each spray hole 110 is stepped from each other to differentiate an extending
length of
each path 120 toward the drum interior.
[73] The spray hole 110 formed along the direction 'a' with a relatively
smaller cross
section is connected with the path 120 extended horizontally toward the drum
interior
and the spray hole 110 formed along the direction 'b' with a relatively larger
cross
section is connected with the path 120 formed in a vertical direction. As a
result, the
wash water sprayed via the spray hole 110 along the direction 'a' is sprayed
along a
drum inside direction with a horizontal speed element at a high pressure, such
that it
may be sprayed to the rear portion of the drum 20 along a vertical direction.
The wash
water via the spray hole 110 formed in the direction 'b' has a vertical speed
element at a
low pressure, such that it is dropped near the front portion of the drum 20
and is not
CA 02721187 2010-10-12
11
WO 2009/128603 PCT/KR2009/000188
sprayed further to the rear portion.
[74] Because of the circulation nozzle 110, the water may be uniformly sprayed
from the
front portion to the rear portion of the drum 20 along a vertical direction of
the drum
20.
[75] In the meantime, according to the controlling method of the embodiment,
in case the
rinsing is performed while rotating the drum 20 after the water supplying
step, the
rinsing may be performed in a similar way of the conventional rinsing.
However, it is
preferable that penetration rinsing may be performed.
[76] Penetration rinsing is performed while rotating the drum 20 at a
relatively high speed
at which the laundry is closely in contact with the inner circumferential
surface of the
drum 20 during the rotation of the drum 20. In this case, the wash water
contained in
the laundry is penetrated through the laundry and discharged outside the drum
20 by
centrifugal force during the rinsing.
[77] The drum 20 is rotated at a relatively high speed in this penetration
rinsing operation,
compared with the rotation speed in a conventional rinsing operation. As
mentioned
above, in order to prevent the rotating drum 20 from being given a resistance
force by
the wash water, it is preferable that the wash water is supplied enough to
maintain the
water level lower than the distance between the tub and the drum 20.
[78] In the meantime, the wash water is circulated to the upper portion of the
tub and of
the drum 20 by the circulation unit as mentioned above, and it is repeatedly
supplied to
the drum 20. This wash water is penetrated through the laundry by the re-
rotation of
the drum 20 at a high speed. Hence, the wash water is discharged outside the
drum 20
and it is held in the lower portion of the tub along an inner surface of the
tub. The wash
water held in the tub is re-circulated to the upper portion of the tub and the
upper
portion of the drum 20 by the circulation unit to be supplied to the drum
interior.
[79] If the wash water is supplied to the rear portion of the drum 20 along a
vertical
direction of the drum 20 by the circulation nozzle 100, the wash water may be
supplied
to the laundry uniformly, and the drum 20 is rotated to perform the
penetration
operation, which makes it possible to enhance rinsing efficiency.
[80] In the meantime, referring to FIG. 3, if the drum 20 is rotated at the
second speed in
both the water supplying step and the rinsing step, the second speed may be
selectable
appropriately to enhance water supplying and rinsing efficiency, for example,
between
approximately 100 to 450 rpm which is higher than the minimum drum speed.
[81] Here, the spinning (S210), water draining (S230), water supplying (S250)
and rinsing
(S270) steps may be performed at one time. As shown in FIG. 3, it is
preferable that
those steps are performed at least two times so that rinsing efficiency may be
improved.
[82] In addition, according to the controlling method of this embodiment, the
rinsing
CA 02721187 2010-10-12
12
WO 2009/128603 PCT/KR2009/000188
course may further include a tumbling rinsing step (S300) next to the above
spinning
(S210), the water draining (S230), the water supplying (S250) and the rinsing
(S270).
The tumbling rinsing step (S300) is performed in a similar way to the
conventional
rinsing of the conventional washing machine and its detailed explanation will
be
omitted.
[83] FIG. 4 is a graph illustrating a rotation speed of the drum 20 of the
washing machine
according to another embodiment of the controlling method. In this embodiment,
a
rotation speed during the water supplying and rinsing step is different,
compared with
the embodiment of FIG. 3. Next, the difference will be described.
[84] According to the controlling method of this embodiment, the drum 20 is
rotated at
the second speed during the water supplying step (S250), and the drum may be
rotated
at a third speed during the rinsing step (S270).
[85] Here, like the above embodiment, the second speed may be preset as high
as the
minimum speed at which the laundry is not spaced apart from the inner
circumferential
surface of the drum 20. However, it is preferable in this embodiment that the
second
speed is preset lower than the second speed of the above embodiment shown in
FIG. 3.
[86] Specifically, since the water supplying and the rinsing are performed at
the identical
drum rotation speed in the embodiment of FIG. 3, the rotation speed is preset
relatively
higher than the minimum drum speed to satisfy the efficiency of water
supplying and
rinsing. In contrast, since the rotation speed of the drum during the water
supplying is
different from the rotation speed during the rinsing in this embodiment of
Fig. 4, the
second speed of the drum during the water supplying is preset lower than the
second
speed of the embodiment shown in FIG. 3, which is higher than and similar to
the
minimum drum speed, for example, 100 - 110 rpm. If the water is supplied at
this
rotation speed of the drum, water supplying is performed more smoothly.
[87] To perform the penetration rinsing step, the drum 20 is rotated at a
third speed and it
is preferable that the third speed is preset to be higher than the minimum
drum speed as
mentioned above. That is, in case of performing the penetration rinsing step,
the
laundry is closely in contact with the inner circumferential surface of the
drum 20 so as
not to be spaced apart therefrom.
[88] In this case, the third rotation speed is preset to be higher than the
minimum drum
speed at which the laundry is not spaced apart from the inner circumferential
surface of
the drum 20. It is preferable that the third speed is lower than the first
speed and higher
than the second speed. If the drum 20 is rotated at the third speed to perform
the pen-
etration rinsing step, the drum 20 should be rotated at a predetermined speed
higher
than the second speed of the water supplying step to perform rinsing.
Furthermore, the
object of the penetration rinsing is not to dehydrate the laundry and it is
preferable that
the third speed of the penetration rinsing step is lower than the first speed
of the
CA 02721187 2010-10-12
13
WO 2009/128603 PCT/KR2009/000188
spinning step.
[89] The spinning step (S210), the water draining step (S230), the water
supplying step
(S250) and the penetration rinsing step (S270) may be performed only one time,
re-
spectively. However, as shown in FIG. 3, it is preferable that they may be
performed
more than one time repeatedly to enhance the rinsing efficiency of the washing
machine.
[90] According to the controlling method of this embodiment, the rinsing cycle
may
further include at least one tumbling rinsing step (S300) after the spinning
step (S210),
the water draining step (S230), the water supplying step (S250) and the
penetration
rinsing step (S270) are performed. The tumbling rinsing step (S300) may be
performed
similar to the rinsing step of the conventional washing machine and its
detailed ex-
planation will be omitted.
[91] The controlling method according to the embodiment is explained, however,
with
reference to the front loading type washing machine and the present invention
is not
limited thereto. It may be applicable to other kinds of washing machines
capable of
performing rinsing while rotating the drum, for example, a top loading type
drum
washing machine.
[92] The rinsing cycle of the overall washing course including the washing,
rinsing and
spinning cycle is explained in the above description and the present invention
is not
limited thereto. For example, the controlling method according to the
embodiment may
be applicable to a case where only the rinsing cycle is performed. If the
order of each
step in the rinsing cycle of FIG. 2 is adjusted, the controlling method can be
applicable
to the case in that only the rinsing cycle is performed. That is, if only the
rinsing is
performed, wash water is not supplied to the tub. As a result, the water
supplying is
performed first and the penetration rinsing step is performed. After that, the
spinning
step and the water draining step may be performed. The detailed explanation of
each
step is identical to that of each step in the above embodiment and it is
omitted.
[93] As mentioned above, according to the controlling method, a time taken to
perform a
rinsing cycle may be reduced.
[94] Furthermore, rinsing efficiency may be improved together with the reduced
time of
the rinsing cycle.
CA 02721187 2010-10-12
