[0001] The present invention relates to a washing machine and control method thereof.
[0002] Generally, a drum type washing machine adopts a washing system using a friction between
a laundry and a drum rotated by receiving a drive force of a motor while a detergent,
water, and laundry are held within the drum. The drum type washing machine is advantageous
in causing less damage to the laundry, preventing the laundry from being raveled,
and providing washing effects of beating and rubbing.
[0003] Meanwhile, in order to cope with the functional improvement and high-quality trend
of the drum type washing machine, a laundry-drying function is provided to the drum
type washing machine as well as the conventional washing and dewatering functions.
Accordingly, the demand for a drum type washier/dryer tends to rise.
[0004] The drum type washer/dryer dries a laundry within a drum in a manner of sucking to
heat an external air using a fan and heater provided outside a tub and blowing the
heated air into the tub.
[0005] FIG. 1 and FIG. 2 are cross-sectional diagrams of a drum type washing machine equipped
with a drying function (washer/dryer) according to a related art, such as is disclosed
in
EP-A-0 829 569.
[0006] Referring to FIG. 1 and FIG. 2, a cylindrical tub 2 is provided within a cabinet
1 and a cylindrical drum 3 is provided within the tub 2. A drive shaft 4 is installed
at a rear part of the drum 3 to be connected to a motor 5. A drive power of the motor
5 is transferred to the drum 3 to rotate. And, a multitude of perforated holes (not
shown in the drawings) are formed on an outer circumference of the drum 3 so that
air or water can pass through the perforated holes.
[0007] In order to perform a drying cycle of the drum type washing machine, a circulation
duct 6 is provided outside the tub 2 to form a circulation path of heated air. Specifically,
both ends of the circulation duct 6 communicate with lower and upper parts of the
tub 2, respectively. And, a blower fan 7 for forcibly blowing air to circulate and
a heater 8 for heating the blown air are installed within the circulation duct 6.
[0008] A cooling water inlet pipe 9 for supplying cooling water from outside for the condensation
of air flowing in the circulation duct 6 is connected to an upper part of the circulation
duct 6. A tub temperature sensor 'B' sensing a temperature within the tub 2 is installed
within the tub 2, and a duct temperature sensor 'A' sensing a temperature of a circulating
air is installed inside the circulation duct 6.
[0009] A method of controlling a drying cycle in the drum type washing machine equipped
with the drying function according to a related art is explained as follows.
[0010] Once a drying cycle is initiated after completion of a dewatering cycle, the blower
fan 7 is driven to suck air into the circulation duct 6. The air blown to flow in
the circulation duct 6 is passed through the heater 8 to be heated at a high temperature
and then flows in the drum 3 to exchange heat with a laundry within the drum 3 for
drying the laundry.
[0011] Meanwhile, the humid air resulting from the heat exchange with the laundry within
the tub 2 flows in the circulation duct 6 again by the operation of the blower fan
7. If the hot and humid air is supplied to the heater 8 via the blower fan 7, performance
of the blower fan 7 is reduced and efficiency of the heater 8 is considerably lowered.
Hence, the cooling water is supplied via the cooling water inlet pipe 9 to condense
the hot and humid air flowing from the tub 2. Thus, humidity of the corresponding
air is lowered.
[0012] The humidity-lowered air is passed through the heater 8 to be heated at a high temperature
and then flows in the tub 2 again, whereby a circulation process of drying the laundry
is repeated.
[0013] In case of circulating the hot air at the high temperature into the tub 2 during
the drying cycle, the motor 5 rotates the drum 3 at a low rotational speed of about
50RPM so that the hot air can evenly come into contact with the laundry.
[0014] In the drum type washing machine equipped with the drying function according to the
related art, if a difference (TA-TB=TC) between a temperature TA sensed by the duct
temperature sensor 'A' and a temperature TB sensed by the tub temperature sensor 'B'
is equal to or greater than a first setup value in each drying cycle mode, if the
temperature TA sensed by the duct temperature sensor 'A' or the temperature TB sensed
by the tub temperature sensor 'B' is equal to or greater than a second setup value,
or if a predetermined time expires from the initiation of the drying cycle, the heater
8 stops being driven but the blower fan 7 is operated during a period of time to perform
a cool air drying. Alternatively, the drying cycle is further performed during an
additional period of time and is then terminated.
[0015] However, in the related art drum type washing machine equipped with the drying function
(washer/dryer), the dewatering cycle is carried out for the dewatering only. After
the dewatering cycle has been completed, the drying cycle is entered to initiate the
corresponding drying. Hence, the drying time is inevitably elongated.
[0016] Namely, the drying cycle adopted by the related art drum type washing machine is
purely carried out for the dewatering only during the dewatering cycle but never performs
a bit of the drying function. Thus, the drying time is elongated, whereby the related
art fails to meet the latest trend or demand for the high drying performance.
[0017] Accordingly, the present invention is directed to a washing machine and control method
thereof that substantially obviates one or more of the problems due to limitations
and disadvantages of the related art.
[0018] An object of the present invention, which has been devised to solve the foregoing
problem, lies in providing a washing machine and control method thereof, by which
a laundry can be dried more effectively.
[0019] It is another object of the present invention to provide a washing machine and control
method thereof, by which a drying cycle time can be shortened.
[0020] It is a further object of the present invention to provide a washing machine and
control method thereof, by which stability and reliance can be enhanced.
[0021] Additional features and advantages of the invention will be set forth in the description
which follows, and in part will be apparent to those having ordinary skill in the
art upon examination of the following or may be learned from a practice of the invention.
The objectives and other advantages of the invention will be realized and attained
by the subject matter particularly pointed out in the specification and claims hereof
as well as in the appended drawings.
[0022] For these objects of the present invention, the present invention includes at least
one or more preliminary drying periods during a dewatering cycle.
[0023] In at least one or each of the preliminary drying periods, a drying heater may be
turned on during a predetermined time, or a time to be determined during operation,
to be operative in dewatering and drying the laundry simultaneously. And, cooling
water for condensing hot and humid air may be supplied during at least one period
of the dewatering cycle.
[0024] To achieve these objects and other advantages in accordance with the present invention,
as embodied and broadly described herein, there is provided a method of controlling
a washing machine according to the appended independent claim 1.
[0025] Preferably, the dewatering cycle sub-routine further includes the step of condensing
hot and humid air produced from the drum during at least one portion of the dewatering
cycle.
[0026] Preferably, the washing machine further includes a cooling water inlet pipe supplying
a cooling water to condense hot and humid air flowing via the air supply path.
[0027] It is to be understood that both the foregoing explanation and the following detailed
description of the present invention are exemplary and illustrative and are intended
to provide further explanation of the invention as claimed.
[0028] 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:
- FIG. 1
- is a cross-sectional diagram of a drum type washing machine equipped with a drying
function according to a related art;
- FIG. 2
- is another cross-sectional diagram of a drum type washing machine equipped with a
drying function according to a related art; and
- FIG. 3
- is a graph of explaining a method of controlling a washing machine according to the
present invention.
[0029] Reference will now be made in detail to the preferred embodiment(s) of the present
invention, examples of which are illustrated in the accompanying drawings. Throughout
the drawings, like elements are indicated using the same or similar reference designations
where possible.
[0030] For the understanding of the present invention, the following description of the
present invention refers to the configuration of the related art drum type washing
machine in FIG. 1 and FIG. 2 without appended explanations since the configuration
and function of a drum type washing machine according to the present invention are
similar to those of the related art drum type washing machine except a function of
a control unit.
[0031] The preferred embodiment of the present invention is explained in detail by referring
to FIGs. 1 to 3 as follows.
[0032] First of all, a drum type washing machine according to the present invention includes
a drying heater 8 heating air to provide hot air, a blower fan 7 forcibly supplying
the hot air to a drum 3 via air supply path, a circulation duct 6 forming the air
supply path, a cooling water inlet pipe 9 connected to the circulation duct 6 to supply
a cooling water for condensing hot and humid air flowing via the circulation duct
6, and a control unit. And, the control unit sequentially executes a washing cycle
sub-routine, a rinsing cycle sub-routine, a dewatering cycle sub-routine, and a drying
cycle sub-routine.
[0033] During a dewatering cycle executed prior to a normal drying cycle, the control unit
turns on the drying heater 8 at least one or more time during a prescribed period
of time each to dewater a laundry and simultaneously to execute a preliminary drying
period for drying the laundry. In executing the dewatering cycle subroutine, the control
unit supplies the cooling water to an inside of the circulation duct 6 via the cooling
water inlet pipe 9 to condense the hot and humid air flowing through the circulation
duct 6.
[0034] A control method of a washing machine according to the present invention is explained
in detail by referring to FIG. 3 as follows.
[0035] FIG. 3 is a graph of explaining a method of controlling a washing machine according
to the present invention.
[0036] Referring to FIG. 3, a dewatering cycle is carried out to dewater a laundry in a
manner of rotating the drum at a plurality of different rotational speeds. The dewatering
cycle includes a plurality of first periods for detecting both eccentricities and
foams by rotating the drum at a low dewatering speed selected from a plurality of
the different rotational speeds, respectively, a plurality of second periods lying
between a plurality of the first periods to rotate the drum at normal dewatering speeds
selected from a plurality of the different rotational speeds and simultaneously to
perform preliminary drying if the eccentricities and foams detected through the first
periods are decided as normal, respectively, a third period lying behind the second
periods to finally rotate the drum at a high dewatering speed selected from a plurality
of the different rotational speeds, and a fourth period lying next to the third period
to perform a process of unraveling the laundry.
[0037] In the embodiment of the present invention, the low dewatering speed is 600 rpm,
the normal dewatering speeds are 900 rpm to 1,000 rpm, and the high dewatering speed
is 1,400 rpm. Meanwhile, the preliminary drying is carried out in a manner of driving
the heater heating the air and the blower fan forcibly supplying the heated air to
the drum. In doing so, the drum 3 is rotated by the motor and the dewatering speeds
are substantially the rotational speeds of the motor, respectively.
[0038] A plurality of preliminary drying periods exist between a plurality of the second
periods for rotating the drum 3 at the low dewatering speed exceeding 600 rpm. Namely,
a plurality of the preliminary drying periods substantially correspond to the second
periods for rotating the drum 3 at the normal dewatering speeds of 900 rpm or 1000
rpm, respectively.
[0039] Meanwhile, each of the preliminary drying periods exists after the detected laundry
eccentricity and foam have been decided as normal. In this case, the eccentricity
corresponds to a distance between a central axis of the drum and a gravity center
of the laundry.
[0040] The control unit enables to execute a step of condensing the hot and humid air produced
from the drum during at least one period of the dewatering cycle. As mentioned in
the foregoing description, in order to condense the hot and humid air flowing through
the circulation duct 6 as the air supply path, the cooling water can be supplied to
the circulation duct 6 via the cooling water inlet pipe 9.
[0041] And, the control unit enables to keep supplying the cooling water to the circulation
duct 6 during the entire periods of the dewatering cycle. Alternatively, the control
unit can periodically supplies the cooling water to the circulation duct 6.
[0042] Moreover, the control unit may keep supplying the cooling water to the circulation
duct 6 during the preliminary drying periods only. Alternatively, the control unit
may periodically keep supplying the cooling water to the circulation duct 6 during
the preliminary drying periods only.
[0043] Besides, the cooling water is supplied to the circulation duct 6 by about 0.5 liter
per minute in the embodiment of the present invention.
[0044] A process of controlling the cycles by the control unit of the drum type washing
machine according to the present invention is explained as follows.
[0045] First of all, a user puts a laundry in the drum 3 and selects a specific washing
course. The control unit then performs the dewatering cycle after completion of the
washing and rinsing cycles.
[0046] In each of the first periods of the dewatering cycle, the drum 3 is rotated at a
rotational speed below 600 rpm to dewater the laundry. In doing so, the control unit
detects the eccentricity and foam to decide whether the detected eccentricity and
foam are normal. And, the control unit turns off the drying heater 8 and the blower
fan 7 not to execute the preliminary drying during each of the first periods.
[0047] While making the drum 3 be rotated at the rotational speed below 600 rpm, the control
unit detects the eccentricity and foam to decide whether the detected eccentricity
and foam are normal. The control unit then rotates the drum 3 in a manner of raising
the dewatering speed up to the low dewatering speed of 600 rpm and then lowering the
dewatering speed down to a basic rpm.
[0048] Subsequently, the control unit re-detects the eccentricity in the period where the
drum 3 is rotated at a speed equal to or smaller than the low dewatering speed of
600 rpm. And, the control unit regards the re-detected eccentricity as a real eccentricity.
[0049] If deciding that the re-detected (secondly detected) eccentricity, i.e., the real
eccentricity, is normal, the control unit raises the dewatering speed up to 900 rpm
of the first normal dewatering speed corresponding to the second period to rotate
the drum 3. Hence, the laundry can be stably dewatered without the eccentricity during
the period having the normal dewatering speed of 900 rpm.
[0050] As mentioned in the foregoing description, when the laundry is dewatered without
the eccentricity, the control unit turns on the drying heater 8 and the blower fan
7 to execute the preliminary drying.
[0051] After the dewatering and the preliminary drying have been performed on the laundry
during a first one of a plurality of the second periods, the control unit stops rotating
the drum 3. In doing so, the control unit turns off the drying heater 8 and the blower
fan 7 as well.
[0052] Subsequently, the control unit finally detects the eccentricity and foam and then
decides whether the finally detected eccentricity and foam are normal. If deciding
the finally detected eccentricity and foam are normal, the control unit raises the
dewatering speed up to 1,000 rpm of the second normal dewatering speed and rotates
the drum 3 during a prescribed time to dewater the laundry within the drum 3. In the
second period for rotating the drum 3 at the second normal dewatering speed of 1,000
rpm, the control unit turns on the drying heater 8 and the blower fan 7 again for
the preliminary drying.
[0053] Meanwhile, after having performed the dewatering and preliminary drying during the
prescribed time by rotating the drum 3 at the second normal dewatering speed of 1,000
rpm, the control unit raises the dewatering speed up to the high dewatering speed
of 1,400 rpm to dewater the laundry by rotating the drum 3 during a prescribed time.
The control unit then reduces the dewatering speed to 'zero' . In this case, the period
for rotating the drum 3 at the high dewatering speed of 1,400 rpm corresponds to the
third period.
[0054] Subsequently, the control unit executes the fourth period for unraveling the laundry.
The unraveling process of the laundry is the last period of the dewatering cycle.
[0055] In each of the preliminary periods, the control unit controls the drying heater 8
so that a temperature of the heated air within the circulation duct can lie within
a prescribed temperature range. In this case, the prescribed temperature range is
previously determined so as not to overheat the air and not to lower the drying performance.
In the embodiment of the present invention, the control unit turns off the drying
heater 8 if the temperature of the heated air is 90°C. And, the control unit turns
on the drying heater 8 if the temperature of the heated air is 87°C.
[0056] Meanwhile, as mentioned in the foregoing description, in performing the dewatering
cycle, the control unit enables the cooling water to be continuously or periodically
supplied to the circulation duct 8 via the cooling water inlet pipe 9. In doing so,
the cooling water is supplied to prevent the steam, which is generated from the heat
exchange between the laundry and the heated air within the drum 3 during the preliminary
drying periods, from escaping via a grip of a detergent box.
[0057] After completion of the above-explained dewatering cycle, the control unit executes
the drying cycle for the drying only. Compared to the conventional dewatering cycle
for performing the dewatering function only, the dewatering cycle according to the
embodiment of the present invention is carried out in a manner of turning on the drying
heater 8 and the blower fan 7 during the prescribed periods to perform both of the
dewatering and the drying on the laundry. As mentioned in the foregoing description,
the drying periods of the dewatering cycle are named 'preliminary drying periods',
respectively. Besides, the cooling water supply enables to prevent the steam from
being discharged via the detergent box.
[0058] Meanwhile, the drum type washing machine is exemplarily used in the embodiment of
the present invention for the application thereto. Yet, it is apparent to those skilled
in the art that the embodiment of the present invention be applicable to the pulsator
type washing machines and other washing machines provided with the dewatering and
drying functions.
[0059] As explained in the foregoing description of the present invention, the preliminary
drying function is executed during the dewatering cycle proceeding prior to the normal
drying cycle as well as the dewatering function.
[0060] Accordingly, the present invention enables to reduce the drying cycle time after
completion of the dewatering cycle. And, the present invention enables to shorten
the overall washing process from the washing cycle to the drying cycle.
[0061] Moreover, the present invention prevents the steam from being discharged to the detergent
box during the respective preliminary drying periods, thereby enabling to enhance
the stability and reliance on the product.
[0062] Summarized, the present invention provides a washing machine and control method thereof,
by which a laundry can be dried more effectively, by which a drying cycle time can
be shortened, and by which stability and reliance can be enhanced. The present invention
includes the step of performing dewatering and preliminary drying simultaneously during
a dewatering cycle. And, The present invention supplies cooling water for condensing
hot and humid air during the dewatering cycle.
[0063] 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 scope of the invention.
Thus, it is intended that the present invention cover such modifications and variations,
provided they come within the scope of the appended claims.
1. A method of controlling a washing machine, the washing machine including a drum (3)
for holding laundry therein, the method comprising the step of
- performing a rinsing cycle;
- performing a dewatering cycle wherein the dewatering cycle comprises turning on
a heater for drying the laundry only when a detected eccentricity and detected foam
meet a predetermined condition; and
- performing a drying cycle.
2. The method of claim 1, wherein the heater (8) heating air and a blower fan (7) forcibly
supplying the heated air to the drum (3) are provided within the washing machine.
3. The method of claim 2, wherein the heater (8) is controlled to leave a temperature
of the heated air within a prescribed range during the at least one preliminary drying
period.
4. The method of claim 3, wherein the heater (8) is turned off if the temperature of
the heated air is 90°C and wherein the heater is turned on if the temperature of the
heated air is 87°C.
5. The method of claim 1, wherein the at least one preliminary drying period is inserted
between a plurality of dewatering periods where the drum (3) is rotated at a plurality
of normal dewatering speeds, respectively.
6. The method of claim 5, wherein a plurality of the normal dewatering speeds are 900
rpm and 1,000 rpm, respectively.
7. The method of claim 1, wherein the at least one preliminary drying period exists after
each corresponding period detecting an eccentricity corresponding to a distance between
a central axis of the drum (3) and a gravity center of the laundry and a foam of the
laundry.
8. The method of claim 1, wherein performing a dewatering cycle comprises condensing
hot and humid air produced from the drum (3) during at least one portion of the dewatering
cycle.
9. The method of claim 8, wherein the condensing step is continuously performed during
the dewatering cycle.
10. The method of claim 8, wherein the condensing step is periodically performed during
the dewatering cycle.
11. The method of claim 8, wherein the condensing step is continuously performed during
the dewatering cycle during the preliminary drying only.
12. The method of claim 8, wherein the condensing step is periodically performed during
the dewatering cycle during the preliminary drying only.
1. Verfahren zum Steuern einer Waschmaschine, wobei die Waschmaschine eine Trommel (3)
aufweist, um darin Wäsche aufzunehmen, wobei das Verfahren Schritte umfasst zum:
- Ausführen eines Spülzyklus;
- Ausführen eines Entwässerungszyklus, wobei der Entwässerungszyklus nur dann ein
Einschalten einer Heizung zum Trocknen der Wäsche umfasst, wenn eine festgestellte
Unwucht und ein festgestellter Schaum eine vorbestimmte Bedingung erfüllen; und
- Ausführen eines Trocknungszyklus.
2. Verfahren nach Anspruch 1, worin die Heizung (8), welche Luft erwärmt, und ein Gebläse
(7), welches die erwärmte Luft der Trommel (3) zwangsweise zuführt, innerhalb der
Waschmaschine angeordnet sind.
3. Verfahren nach Anspruch 2, worin die Heizung (8) so gesteuert wird, dass eine Temperatur
der erwärmten Luft während des wenigstens einen Vortrocknungszeitraums innerhalb eines
vorgegebenen Bereichs gehalten wird.
4. Verfahren nach Anspruch 3, worin die Heizung (8) ausgeschaltet wird, wenn die Temperatur
der erwärmten Luft 90 °C beträgt, und worin die Heizung eingeschaltet wird, wenn die
Temperatur der erwärmten Luft 87 °C beträgt.
5. Verfahren nach Anspruch 1, worin der wenigstens eine Vortrocknungszeitraum zwischen
mehrere Entwässerungsvorgänge eingefügt wird, bei denen die Trommel (3) bei mehreren
normalen Entwässerungsdrehzahlen gedreht wird.
6. Verfahren nach Anspruch 5, worin die mehreren normalen Entwässerungsdrehzahlen 900
Umdrehungen pro Minute bzw. 1.000 Umdrehungen pro Minute betragen.
7. Verfahren nach Anspruch 1, worin der wenigstens eine Vortrocknungszeitraum nach jeweils
jedem Zeitraum vorgesehen ist, in welchem eine einem Abstand zwischen einer Mittenachse
der Trommel (3) und einem Schwerpunkt der Wäsche entsprechende Unwucht und Schaum
von der Wäsche erfasst werden.
8. Verfahren nach Anspruch 1, worin das Ausführen eines Entwässerungszyklus ein Kondensieren
von heißer und feuchter Luft umfasst, die während wenigstens eines Abschnitts des
Entwässerungszyklus aus der Trommel (3) austritt.
9. Verfahren nach Anspruch 8, worin der Schritt zum Kondensieren während des Entwässerungszyklus
ohne Unterbrechung ausgeführt wird.
10. Verfahren nach Anspruch 8, worin der Schritt zum Kondensieren während des Entwässerungszyklus
mit Unterbrechung ausgeführt wird.
11. Verfahren nach Anspruch 8, worin der Schritt zum Kondensieren während des Entwässerungszyklus
nur während der Vortrocknung ohne Unterbrechung ausgeführt wird.
12. Verfahren nach Anspruch 8, worin der Schritt zum Kondensieren während des Entwässerungszyklus
nur während der Vortrocknung mit Unterbrechung ausgeführt wird.
1. Procédé de commande d'une machine à laver, la machine à laver incluant un tambour
(3) pour y renfermer du linge, le procédé comprenant les étapes de :
- mise en oeuvre d'un cycle de rinçage ;
- mise en oeuvre d'un cycle d'essorage, le cycle d'essorage comprenant la mise sur
marche d'un chauffage pour ne sécher le linge que si une excentricité détectée et
une mousse détectée satisfont à une condition prédéterminée ; et
- mise en oeuvre d'un cycle de séchage.
2. Procédé selon la revendication 1, dans lequel sont prévus, au sein de la machine à
laver, le chauffage (8) chauffant l'air et un ventilateur soufflant (7) alimentant
à force le tambour (3) en air chauffé..
3. Procédé selon la revendication 2, dans lequel le chauffage (8) est commandé pour laisser
une température de l'air chauffé au sein d'une gamme prescrite, au cours de ladite
au moins une période de séchage préliminaire.
4. Procédé selon la revendication 3, dans lequel le chauffage (8) est mis sur arrêt si
la température de l'air chauffé est de 90°C et dans lequel le chauffage est mis sur
marche si la température de l'air chauffé est de 87°C.
5. Procédé selon la revendication 1, dans lequel ladite au moins une période de séchage
préliminaire est insérée entre une pluralité de périodes d'essorage où le tambour
(3) tourne, respectivement, à une pluralité de vitesses d'essorage normales.
6. Procédé selon la revendication 5, dans lequel une pluralité de vitesses d'essorage
normales sont, respectivement, 900 tours/min et 1000 tours/min.
7. Procédé selon la revendication 1, dans lequel ladite au moins une période de séchage
préliminaire existe après chaque période correspondante détectant une excentricité
correspondant à une distance entre un axe central du tambour (3) et un centre de gravité
du linge, et une mousse du linge.
8. Procédé selon la revendication 1, dans lequel la mise en oeuvre d'un cycle d'essorage
comprend la condensation de l'air chaud et humide produit depuis le tambour (3) au
cours d'au moins une portion du cycle d'essorage.
9. Procédé selon la revendication 8, dans lequel l'étape de condensation est mise en
oeuvre en continu au cours du cycle d'essorage.
10. Procédé selon la revendication 8, dans lequel l'étape de condensation est mise en
oeuvre périodiquement au cours du cycle d'essorage.
11. Procédé selon la revendication 8, dans lequel l'étape de condensation est mise en
oeuvre en continu au cours du cycle d'essorage, seulement pendant le séchage préliminaire.
12. Procédé selon la revendication 8, dans lequel l'étape de condensation est mise en
oeuvre périodiquement au cours du cycle d'essorage, seulement pendant le séchage préliminaire.