[0001] The present invention relates to the field of control methods of washer dryers, and
also relates to a washer dryer.
[0002] Research has found that steam has care effects such as wrinkle removal, sterilization,
and deodorization on fabrics. Therefore, various laundry care machines apply the steam
to a care program to provide specialized care for laundry.
[0003] To generate steam, a common and easy-to-think approach is to introduce a steam generating
device. For example, water in a specially arranged water container is heated, or water
mists are generated by using an atomization device, and then the water mists are heated.
As a result, this not only increases costs of a machine, but also takes up the already
cramped space in the machine, which increases design difficulty and maintenance costs
of the machine.
[0004] An object of the present invention is to generate steam through a new control method
by using existing hardware of a washer dryer, thereby giving steam care to laundry.
[0005] Embodiments of the present invention disclose a method of controlling a washer dryer
to give steam care to laundry. The washer dryer includes a circulating air duct with
two ends in communication with a treatment tub. A heating device and a blowing device
are arranged in the circulating air duct. A water supply device is configured to introduce
water flow into the circulating air duct or along a tub wall of the treatment tub.
A rotatable drum is arranged in the treatment tub, and a gap exists between the drum
and the treatment tub. The control method includes the following steps:
step I (S101): causing the blowing device to rotate at a first rotational speed to
generate air flow in the circulating air duct, the air flow circulating in the circulating
air duct and the treatment tub;
step II (S 102): turning on and controlling the heating device, heating air flow passing
through the heating device, and causing an air temperature downstream of the heating
device to reach a first temperature; and
step III (S103): turning on the water supply device, so that the water flow exchanges
heat with the air flow heated by the heating device and is at least partially evaporated
into steam.
[0006] In an optional implementation, after the water supply device is turned on, the drum
is caused to rotate at the first rotational speed, where the first rotational speed
is greater than or equal to a minimum dehydration rotational speed.
[0007] An optional implementation further includes that a level of water supplied by the
water supply device and finally entering the treatment tub is detected after the water
supply device is turned on, and the drum is caused to rotate at the first rotational
speed when the water level reaches a first predetermined water level, where the first
predetermined water level is less than or equal to a water level of a water surface
that exactly reaches an outer surface of the drum.
[0008] Preferably, the drum switches to rotate at a second rotational speed after rotating
at the first rotational speed for a first predetermined duration, where the second
rotational speed is set to be less than the minimum dehydration rotational speed,
and laundry is rotatable at the second rotational speed.
[0009] Preferably, the drum is rotated in a single direction at the first rotational speed,
and the drum is rotated alternately in two directions at the second rotational speed.
[0010] In an embodiment, the drum is rotated alternately at the first rotational speed and
the second rotational speed.
[0011] An optional implementation further includes that the first temperature is a highest
safe temperature for fabrics.
[0012] In addition, after the heating device is turned on for a predetermined time or a
predetermined stage, the heating device is controlled to reduce the air temperature
downstream of the heating device to a second temperature.
[0013] An optional implementation further includes that after the water supply device is
turned on, the water supply device is turned on and turned off at a preset frequency,
and the blowing device and the heating device are kept on during turn-off of the water
supply device.
[0014] In some optional embodiments, the water supply device includes a first water supply
device with a great flow rate and a second water supply device with a small flow rate.
On this condition, only the first water supply device is preferably turned on.
[0015] In an implementation of the water supply device, the circulating air duct includes
a heat exchange region, and the water supply device is configured to spray water to
a wall of the heat exchange region.
[0016] With the water supply from the water supply device, the water level in the treatment
tub may rise, which may result in water entering the drum to soak the laundry in the
drum. Therefore, the water level in the treatment tub is detected after the water
supply device is turned on, and a drainage device is turned on to drain the water
in the treatment tub when the water level reaches a second predetermined water level,
where the second predetermined water level is less than a level of water that exactly
reaches an outer surface of the drum.
[0017] When the drainage device is turned on for a third preset duration, or when it is
detected that the water level of the treatment tub is less than or equal to a third
predetermined water level, the drainage device is turned off.
[0018] In an embodiment, the water supply device is turned off when the water level reaches
the second predetermined water level, the water supply device is turned on again when
the water level is less than or equal to the third predetermined water level, and
the blowing device and the heating device are kept on before the water supply device
is turned on again after being turned off.
[0019] An optional implementation further includes that after the water supply device is
turned on, a drainage device is turned on and turned off at a predetermined frequency
that prevents water from entering the drum to drain the water in the treatment tub.
[0020] In a case that technical conditions permit, the foregoing various embodiments may
be arbitrarily combined in various manners.
[0021] The present invention further provides a washer dryer, including a circulating air
duct with two ends in communication with a treatment tub. A heating device and a blowing
device are arranged in the circulating air duct. A water supply device is configured
to introduce water flow into the circulating air duct. A rotatable drum is arranged
in the treatment tub. A gap exists between the drum and the treatment tub. The washer
dryer further includes a control device. The control device is arranged to control
operation of the washer dryer according to the method of any one or any combination
of the various embodiments described above.
[0022] A user-selectable steam care program is preset in the control device, and after the
steam care program is started. The control device is configured to control the operation
of the washer dryer according to the method of at least any one or any combination
of the various embodiments described above.
[0023] According to the washer dryer and the control method thereof of the present invention,
steam may be generated by using a basic configuration of a machine without adding
a special steam generating device, and the steam care is given to the laundry. In
addition, since hot air passing through the circulating air duct has a high flow speed,
a great flow rate, concentrated heat, and a good effect on water evaporation, a large
amount of steam may be generated per unit time, which has a good care effect on the
laundry. However, the water flow introduced along the tub wall of the treatment tub
has a large diffusion area and a large contact area with the hot air, and therefore
the amount of steam generated per unit time is also large.
[0024] Some specific embodiments of the present invention are illustrated below with reference
to the accompanying drawings.
FIG. 1 is a schematic diagram of a washer dryer.
FIG. 2 is a flowchart of at least part of steps of a method of controlling a washer
dryer to give steam care to laundry.
[0025] As shown in FIG. 1, a washer dryer 100 includes a treatment tub 2 and a drum 4 rotatably
arranged in the treatment tub 2. A gap exists between the drum 4 and the treatment
tub 2. Fine through holes are provided on a drum wall of the drum 4, so that water
and air may circulate between the drum 4 and the treatment tub 2. A bottom of the
treatment tub 2 is in communication with a drainage device 6. The drainage device
6 includes a drainage pipeline 61 and a drainage pump 62 arranged on the drainage
pipe 61.
[0026] The washer dryer 100 further includes a sensor 7 for detecting parameters related
to an amount of water in the treatment tub 2. The parameters related to the amount
of water may be water inflow, a water level, a water pressure, and the like. The sensor
7 may be installed in various positions. In an embodiment shown in FIG. 1, the sensor
7 is installed on the bottom of the treatment tub 2. Specifically, a water pressure
sensor may be used to obtain a relative height of the water level. In another implementation,
a sensor for sensing a position of a horizontal plane may also be arranged in a position
at a corresponding target water level on the tub wall of the treatment tub 2.
[0027] The washer dryer 100 further includes a circulating air duct 8. Both ends of the
circulating air duct 8 are in communication with the treatment tub 2. A heating device
1 and a blowing device 3 are arranged in the circulating air duct 8. In the embodiment
shown in FIG. 1, the circulating air duct 8 includes a heat exchange region 81, and
a water supply device 5 is configured to spray water to a wall of the heat exchange
region 81. In the embodiment, the water supply device 5 includes a first water supply
device 51 and a second water supply device 52. The first water supply device 51 has
a great flow rate and is configured to flush lint attached to the heat exchange region
81 and a region below the heat exchange region. The second water supply device 52
has a small unit flow rate. After the second water supply device is turned on, water
may be provided for heat exchange with hot and humid air to dry laundry during drying.
[0028] In another embodiment, the water supply device 5 may include only one water supply
device.
[0029] In another embodiment, the water supply device 5 may be located in another region
and spray water to another part. For example, the water supply device may be located
near the blowing device 3 to spray water to the blowing device 3, which may be configured
to flush lint attached to the blowing device 3. For example, the water supply device
may also be located near the heating device 1, or may be arranged along the tub wall
of the treatment tub 2 to introduce water flow along the tub wall of the treatment
tub 2, so as to provide, in a general drying program, water for heat exchange with
the hot and humid air to dry the laundry.
[0030] The washer dryer 100 further includes a control device 10. According to program settings,
for example, the heating device 1, the blowing device 3, the water supply device 5,
and the drainage pump 62 may be controlled, so as to give various care to the laundry,
such as washing, drying, and steam care.
[0031] A user-selectable steam care program is preset in the control device 10. After the
steam care program is started, the control device controls the washer dryer 100 to
operate and apply steam St to the laundry in the drum 4, so as to achieve effects
such as wrinkle removal, sterilization, and deodorization on the laundry. The steam
care program may be independently run to give care to dry laundry placed in the drum
4, or may be run after another program such as a drying program, to achieve a better
effect of wrinkle removal on the laundry or reduce a large number of wrinkles caused
by the dried laundry that have not been taken out for a long time.
[0032] The following is a detailed description of the method of controlling a washer dryer
to give steam care. However, various embodiments described below cannot exhaust all
embodiments within a technical concept of the present invention.
[0033] As shown in FIG. 2, the method of controlling a washer dryer to give steam care to
laundry includes at least the following steps.
[0034] Step I S 101: Cause a blowing device 3 to rotate at a first rotational speed to generate
air flow in the circulating air duct 8, the air flow circulating in the circulating
air duct 8 and the treatment tub 2.
[0035] Step II S102: Turn on and control a heating device 1, heat air flow passing through
the heating device 1, and cause an air temperature downstream of the heating device
1 to reach a first temperature.
[0036] Step III S103: Turn on the water supply device 5, so that the water flow exchanges
heat with the air flow heated by the heating device 1 and is at least partially evaporated
into steam St.
[0037] The steam St flows through the laundry in the drum 4 with the air flow, thereby producing
care effects such as wrinkle removal, sterilization, and deodorization on the laundry.
[0038] In an optional embodiment, step III is followed by step IV S104 of causing the drum
to rotate at a high speed. In the step, the drum 4 is caused to rotate at a first
rotational speed, where the first rotational speed is greater than or equal to a minimum
dehydration rotational speed. For example, if a preset dehydration rotational speed
of a specific washer dryer 100 including the control step is between 800 revolutions
per minute and 1200 revolutions per minute, the first rotational speed in step IV
is set to at least 800 revolutions per minute.
[0039] Water supplied by the water supply device 5 to the circulating air duct 8 or the
treatment tub 2 eventually reaches a bottom of the treatment tub 2. Therefore, the
drum 4 may drive the air flow to flow when rotating at the foregoing rotational speed.
Particularly, the air flow between the drum 4 and the treatment tub 2 pushes the water
at the bottom of the treatment tub 2 to form a water film on a surface of the treatment
tub 2. The water film contacts the hot air and vaporizes to obtain the steam, which
increases a way of generating steam and increases a steam concentration.
[0040] A level of water supplied by the water supply device 5 and finally entering the treatment
tub 2 is detected after the water supply device 5 is turned on, and the drum 4 is
caused to rotate at the first rotational speed when the water level reaches a first
predetermined water level L1. The first predetermined water level L1 is less than
or equal to the water level of a water surface that exactly reaches an outer surface
of the drum 4.
[0041] The level of water supplied by the water supply device 5 and finally entering the
treatment tub 2 may be detected in a direct manner. For example, a sensor for sensing
arrival of the water surface at a predetermined water level height position is arranged
in the position on the tub wall of the treatment tub 2. Alternatively, the water level
may be detected in an indirect manner. For example, a pressure sensor is used to detect
a water pressure in real time. The water pressure corresponds to a corresponding predetermined
water level when reaching a predetermined magnitude. The water levels mentioned below
are all applicable to the implementation described in this paragraph.
[0042] If the first predetermined water level L1 is less than or equal to the water level
of the water surface that exactly reaches the outer surface of the drum 4, the water
does not wet the laundry in the drum 4. In addition, a preferred implementation is
that the first predetermined water level L1 is set so that the water surface exactly
touches the outer surface of the drum 4 or is very close to the outer surface of the
drum 4. In this way, more water may be driven, and the water reaches a higher position
on the surface of the treatment tub 2, thereby forming a water film with a larger
area and providing a larger amount of steam.
[0043] To avoid new wrinkles caused by laundry squeezing each other as a result of long-term
rotation of the drum 4 at the dehydration rotational speed, the drum 4 switches to
rotate at a second rotational speed after rotating at the first rotational speed for
a first predetermined duration. The second rotational speed is set to be less than
the minimum dehydration rotational speed, and laundry may be rotated at the second
rotational speed. It may be seen that the second rotational speed is less than a centrifugal
rotational speed that causes the laundry to be attached to the drum, and the laundry
may be rotated in the drum 4, so that all parts fully contact the steam, the laundry
is looser as a whole, and wrinkles are reduced. The second rotational speed may be
obtained in advance through experiments.
[0044] The drum 4 is rotated in a single direction at the first rotational speed, and the
drum 4 is rotated alternately in two directions at the second rotational speed. The
alternate rotation may better prevent laundry entanglement, so that the laundry is
fully rotated and shaken loose.
[0045] The drum 4 may rotate only once at the first rotational speed, or the drum 4 may
rotate alternately at the first rotational speed and the second rotational speed.
If the drum 4 is rotated alternately at the first rotational speed and the second
rotational speed, a duration of rotation at the first rotational speed is to be set
shorter to reduce a possibility of wrinkles caused by centrifugal extrusion of the
laundry against each other. An advantage of intermittently rotating the drum 4 at
the first rotational speed is that the water film is generated on the wall of the
treatment tub 2, and a new water film is continuously generated after the water film
is evaporated, thereby continuously generating steam in this manner.
[0046] The first temperature used in step II S102 is a highest safe temperature for fabrics.
The temperature may be obtained by using a temperature sensor 9 arranged downstream
of the heating device 1 in an air flow direction shown in FIG. 1. The first temperature
is set higher, so that a higher temperature is quickly obtained in a space where air
flows, which improves evaporation efficiency.
[0047] In addition, after the heating device 1 is turned on for a predetermined time or
a predetermined stage, the heating device 1 is controlled to reduce the air temperature
downstream of the heating device 1 to a second temperature. In this way, more care
may be given to the laundry, and the laundry may be prevented from being damaged due
to a long-term high temperature.
[0048] A preferred embodiment further includes that after the water supply device 5 is turned
on, the water supply device 5 is turned on and turned off at a preset frequency, and
the blowing device 3 and the heating device 1 are kept on during turn-off of the water
supply device 5. After the water supply device 5 is turned on, water may form a water
film on a surface of the circulating air duct 8 and/or the treatment tub 2. After
the water supply device 5 is turned off, circulating hot air may heat and evaporate
the water film. After the water film is evaporated, the water supply device 5 is turned
on again to generate a new water film. In this way, water may be saved to avoid a
waste of water caused by continuous water supply from the water supply device 5.
[0049] When the water supply device 5 includes a first water supply device 51 with a great
flow rate and a second water supply device 52 with a small flow rate. On this condition,
only the first water supply device 51 is preferably turned on.
[0050] With the water supply from the water supply device 5, the water level in the treatment
tub 2 may rise, which may result in water entering the drum 4 to soak the laundry
in the drum 4. Therefore, after the water supply device 5 is turned on, the water
level in the treatment tub 2 is detected in real time. When the water level reaches
a second predetermined water level L2, the drainage device 6 is turned on to drain
the water in the treatment tub 2. The second predetermined water level L2 is less
than a level of water that exactly reaches the outer surface of the drum 4. For the
control method including step IV S104, the second predetermined water level L2 may
be the same as the first predetermined water level L1. Moreover, a manner in which
the water exactly reaches the outer surface of the drum 4 is only to be used in a
scenario where the drum 4 is rotated at the first rotational speed. In another scenario,
the water surface is to be kept at a distance from the drum 4 to prevent the water
from wetting the laundry in the drum 4.
[0051] When the drainage device 6 is turned on for a third preset duration, or when it is
detected that the water level of the treatment tub 2 is less than or equal to a third
predetermined water level L3, the drainage device 6 is turned off. The third predetermined
water level L3 is less than the first predetermined water level L1 and the second
predetermined water level L2, and a relatively small parameter is to be selected.
[0052] In an embodiment, when the water level reaches the second predetermined water level
L2, the water supply device 5 is turned off after the drainage device 6 is turned
on or while the drainage device 6 is being turned on. When the water level is less
than or equal to the third predetermined water level L3, the water supply device 5
is turned on again. In addition, before the water supply device 5 is turned on again
after being turned off, the blowing device 3 and the heating device 1 are kept on.
[0053] In another optional implementation, it is not determined based on the water level
whether the drainage device 6 is turned on, but after the water supply device 5 is
turned on, the drainage device 6 is turned on and turned off at a predetermined frequency
that prevents water from entering the drum 4, to drain the water in the treatment
tub. The predetermined frequency may be determined in advance by calculating water
supply of the water supply device 5 or by experiments.
[0054] In a steam care program, the foregoing process of generating the steam lasts for
a set duration, or the duration of the foregoing process is adjusted based on a detected
air humidity within the treatment tub 2 or the circulating air duct 8. Subsequently,
in an embodiment, processes such as dehumidification, cooling, and maintenance are
performed.
[0055] Various specific implementations described above and shown in the accompanying drawings
are merely used for describing the present invention. Within the scope of the basic
technical idea of the present invention, any form of changes made to the present invention
by a person of ordinary skill in the related art fall within the protection scope
of the present invention.
1. A method of controlling a washer dryer (100) to give steam care to laundry, wherein
the washer dryer (100) comprises a circulating air duct (8) with both ends in communication
with a treatment tub (2), a heating device (1) and a blowing device (3) are arranged
in the circulating air duct, a water supply device (5) is configured to introduce
water flow into the circulating air duct or along a tub wall of the treatment tub,
a rotatable drum (4) is arranged in the treatment tub, and a gap exists between the
drum and the treatment tub,
characterized in that the control method comprises the following steps:
step I (S101): causing the blowing device to rotate at a first rotational speed to
generate air flow in the circulating air duct, the air flow circulating in the circulating
air duct and the treatment tub;
step II (S102): turning on and controlling the heating device, heating air flow passing
through the heating device, and causing an air temperature downstream of the heating
device to reach a first temperature; and
step III (S103): turning on the water supply device, so that the water flow exchanges
heat with the air flow heated by the heating device and is at least partially evaporated
into steam.
2. The control method according to claim 1, characterized in that after the water supply device is turned on, the drum is caused to rotate at the first
rotational speed, wherein the first rotational speed is greater than or equal to a
minimum dehydration rotational speed.
3. The control method according to claim 2, characterized in that a level of water supplied by the water supply device and finally entering the treatment
tub is detected after the water supply device is turned on, and the drum is caused
to rotate at the first rotational speed when the water level reaches a first predetermined
water level, wherein the first predetermined water level is less than or equal to
a water level of a water surface that exactly reaches an outer surface of the drum.
4. The control method according to claim 2, characterized in that the drum switches to rotate at a second rotational speed after rotating at the first
rotational speed for a first predetermined duration, wherein the second rotational
speed is set to be less than the minimum dehydration rotational speed, and laundry
is rotatable at the second rotational speed.
5. The control method according to claim 4, characterized in that the drum is rotated in a single direction at the first rotational speed, and the
drum is rotated alternately in two directions at the second rotational speed.
6. The control method according to claim 4, characterized in that the drum is rotated alternately at the first rotational speed and the second rotational
speed.
7. The control method according to claim 1, characterized in that the first temperature is a highest safe temperature for fabrics.
8. The control method according to claim 7, characterized in that after the heating device is turned on for a predetermined time or a predetermined
stage, the heating device is controlled to reduce the air temperature downstream of
the heating device to a second temperature.
9. The control method according to claim 1, characterized in that after the water supply device is turned on, the water supply device is turned on
and turned off at a preset frequency, and the blowing device and the heating device
are kept on during turn-off of the water supply device.
10. The control method according to claim 1, characterized in that the water supply device comprises a first water supply device with a great flow rate
and a second water supply device with a small flow rate, wherein only the first water
supply device is turned on.
11. The control method according to claim 1, characterized in that the circulating air duct comprises a heat exchange region, and the water supply device
is configured to spray water to a wall of the heat exchange region.
12. The control method according to claim 1, characterized in that the water level in the treatment tub is detected after the water supply device is
turned on, and a drainage device is turned on to drain the water in the treatment
tub when the water level reaches a second predetermined water level, wherein the second
predetermined water level is less than a level of water that exactly reaches an outer
surface of the drum.
13. The control method according to claim 12, characterized in that when the drainage device is turned on for a third preset duration, or when it is
detected that the water level of the treatment tub is less than or equal to a third
predetermined water level, the drainage device is turned off.
14. The control method according to claim 13, characterized in that the water supply device is turned off when the water level reaches the second predetermined
water level, the water supply device is turned on again when the water level is less
than or equal to the third predetermined water level, and the blowing device and the
heating device are kept on before the water supply device is turned on again after
being turned off.
15. The control method according to claim 1, characterized in that after the water supply device is turned on, a drainage device is turned on and turned
off at a predetermined frequency that prevents water from entering the drum to drain
the water in the treatment tub.
16. A washer dryer, characterized by comprising a circulating air duct (8) with two ends in communication with a treatment
tub (2), wherein a heating device (1) and a blowing device (3) are arranged in the
circulating air duct, a water supply device (5) is configured to introduce water flow
into the circulating air duct, a rotatable drum (4) is arranged in the treatment tub,
and a gap exists between the drum and the treatment tub, and characterized by further comprising a control device (10), wherein the control device is arranged
to control operation of a washer dryer according to the method of any of claims 1
to 15.
17. The washer dryer according to claim 16, characterized in that a user-selectable steam care program is preset in the control device, and after the
steam care program is started, the control device controls the operation of the washer
dryer according to at least one of claims 1 to 14.