Title of Invention

A CONTROL METHOD OF A WASHING MACHINE

Abstract Disclosed is a control method of a washing machine comprising the steps of (a) setting a washing pattern in the present operation of the washing machine in consideration of hardness of the water calculated in the previous operation of the washing machine, (b) operating the washing machine based on the set washing pattern, and (c) calculating and storing hardness of the water in the present operation of the washing machine to set a next washing pattern in the next operation of the washing machine, thereby having the optimum washing or rinsing capacity of the washing machine in consideration of different characteristics of water by regional groups.
Full Text PCT/KR2004/001256
RO/KR 23.07.2004
CONTROL METHOD OF WASHING MACHINE
Technical Field
The present invention relates to a control method of a washing
machine, and more particularly to a control method of a washing machine, in
which a washing operation is performed based on the optimum washing
pattern in consideration of the hardness of water supplied to the washing
machine.
Background Art
Generally, a washing machine is an apparatus providing a mechanical
action using electricity, thereby removing dirt from clothes. When the clothes
are put into water containing a detergent dissolved therein, dirt is removed
from the clothes by a chemical action of the detergent. However, since it takes
a long time to remove the dirt from the clothes by the chemical action of the
detergent alone, the dirt can be easily removed from the clothes by forcibly
generating a rotary current or applying a mechanical action such as friction or
vibration to the clothes.
The washing machine comprises an outer tub, an inner tub rotatably
placed in the outer tub for containing clothes, a wash vane rotatably installed in
the inner tub for generating a washing current, and a motor and a clutch
installed below the lower part of the outer tub for rotating the inner tub or the
wash vane.
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The above washing machine has different washing and rinsing
capacities according to the quantity of the clothes, the quantity of the detergent,
and the hardness of wash water. In a conventional control method of the
washing machine, the quantity of the clothes putted into the inner tub is sensed,
a washing pattern including washing time, rinsing frequency, rinsing time,
dehydrating time, etc. is set based on the sensed quantity of the clothes, and the
washing machine is operated according to the set washing pattern.
However, the conventional control method of the washing machine
considers only the quantity of the clothes while disregarding the hardness of the
water supplied to the washing machine, thus causing a limit in improving
washing or rinsing capacity of the washing machine.
Disclosure of the Invention
Therefore, the present invention has been made in view of the above
problems, and it is an object of the present invention to provide a control
method of a washing machine, in which a washing pattern is determined in
consideration of characteristics of supplied water, thereby improving washing
or rinsing capacity.
In accordance with one aspect of the present invention, the above and
other objects can be accomplished by the provision of a control method of a
washing machine comprising the steps of: (a) setting a present washing
pattern in consideration of the hardness of the water calculated and stored in
the previous operation of the washing machine; (b) operating the washing
machine based on the set present washing pattern; and (c) calculating and
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storing the hardness of the water in the present operation of the washing
machine for setting a next washing pattern for the next operation of the
washing machine.
Preferably, the hardness of the water stored in the previous operation
of the washing machine may be automatically loaded when power is inputted
to the washing machine.
Further, preferably, the hardness of the water in the present
operation of the washing machine may be calculated after water in the
washing machine is agitated for a predetermined time or more.
Moreover, preferably, step (c) may include the sub-steps of: (c-1)
measuring temperature and conductivity of the water; and (c-2) calculating
the hardness of the water based on the temperature and conductivity of the
water measured in sub-step (c-1).
Preferably, sub-step (c-1) may be performed a predetermined time
before a final rinsing operation is completed.
Further, preferably, the washing pattern may include at least one of
washing intensity, supplied water level, washing time, rinsing frequency,
rinsing time, and dehydrating time.
Moreover, preferably, in step (a), in case that the washing machine is in
an initial operation, the washing pattern may be set based on an already-
inputted standard hardness of the water.
Preferably, in step (c), in case that the washing machine is operated
plural times, the cumulative mean of the hardnesses of water in the plural
operations of the washing machine may be calculated and stored.
Further, preferably, in step (c), in case that the washing machine is
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operated four times or more, the cumulative mean of the hardnesses of water in
the plural operations of the washing machine except for the maximum and
minimum hardnesses of water may be calculated and stored.
Moreover, preferably, in step (c), in case that the washing machine is
operated times corresponding to a predetermined frequency or more, the
running mean of the hardnesses of water in the plural operations of the
washing machine may be calculated and stored.
Preferably, the set present washing pattern may be displayed so that it
is recognized by users.
In accordance with another aspect of the present invention, there is
provided a control method of a washing machine comprising the steps of: (I)
sensing the quantity of clothes after instructions for operating the washing
machine are inputted to the washing machine, and setting a washing pattern
based on the sensed quantity of clothes; (II) supplying water based on the
washing pattern set in step (I), and dissolving a detergent in the water; (III)
measuring conductivity and temperature of the water containing the detergent,
calculating the quantity of the detergent in consideration of the hardness of the
water calculated and stored in the previous operation of the washing machine,
and resetting the washing pattern based on the calculated quantity of the
detergent; and (IV) performing a washing or rinsing operation based on the
reset washing pattern, and calculating and storing the hardness of the water
in a final rising operation.
In accordance with yet another aspect of the present invention, there
is provided a control method of a washing machine comprising the steps of: (I)
setting a washing pattern based on the hardness of the water calculated and
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stored in the previous operation of the washing machine after instructions for
operating the washing machine are inputted to the washing machine; (II)
supplying water based on the washing pattern set in step (I), and dissolving a
detergent in the water; (III) measuring conductivity and temperature of the
water containing the detergent, calculating the quantity of the detergent in
consideration of the hardness of the water calculated and stored in the
previous operation of the washing machine, and resetting the washing pattern
based on the calculated quantity of the detergent; and (IV) performing a
washing or rinsing operation based on the reset washing pattern, and
calculating and storing the hardness of the water in a final rising operation.
Preferably, in step (I), washing, rinsing and dehydrating times of the
set washing pattern may be displayed so that they are recognized by users.
Further, preferably, in step (III), the conductivity and temperature of
the water containing the detergent dissolved therein may be displayed to the
outside through a sensor operation display so that they are recognized by
users during the measurement thereof.
Moreover, preferably, in step (III), one table may be selected from a
plurality of tables containing quantities of the detergent according to
hardnesses of water, and the quantity of the detergent corresponding to the
conductivity and temperature of the water containing the detergent dissolved
therein may be calculated from the selected table.
Preferably, in step (III), in case that the washing machine is in an
initial operation, the washing pattern may be set based on an already-inputted
standard hardness of the water.
Further, preferably, step (IV) may include the sub-steps of: (i)
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measuring temperature and conductivity of the water in a final rinsing
operation; and (ii) calculating the hardness of the water based on the
temperature and conductivity of the water measured in sub-step (i).
More preferably, sub-step (i) may be performed after water in the
washing machine is agitated for a predetermined time or more.
Alternately, sub-step (i) may be performed a predetermined time
before a final rinsing operation is completed.
Moreover, preferably, in step (IV), residual washing, rinsing and
dehydrating times changed by the reset washing pattern may be displayed.
Preferably, in step (IV), in case that the washing machine is operated
plural times, the cumulative mean of the hardnesses of water in the plural
operations of the washing machine may be calculated and stored.
Further, preferably, in step (c), in case that the washing machine is
operated four times or more, the cumulative mean of the hardnesses of water in
the plural operations of the washing machine except for the maximum and
minimum hardnesses of water may be calculated and stored.
Moreover, preferably, in step (c), in case that the washing machine is
operated times corresponding to a predetermined frequency or more, the
running mean of the hardnesses of water in the plural operations of the
washing machine may be calculated and stored.
The control method of the present invention uses hardness of the
water calculated in the previous operation of the washing machine to set a
washing pattern of the present operation of the washing machine in
consideration of different characteristics of water by regional groups, thereby
having optimum washing and rinsing capacities and minimizing water and
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energy consumption.
The control method of the present invention displays a variation in
the washing pattern to users, thereby improving convenience and utility of the
washing machine.
The control method of the present invention calculates hardness of
the water, from which a detergent is completely removed in a final rinsing
operation of the present operation of the washing machine, thereby being
capable of calculating the accurate quantity of the detergent for the next
operation of the washing machine, not requiring a separation step for
calculating the hardness of the water, and reducing the overall washing time.
The control method of the present invention, in case that the washing
machine is operated plural times, calculates and stores the cumulative mean
of the hardnesses of water in the plural operations of the washing machine,
thereby reducing the variation of the hardness of the water and obtaining more
stable and accurate measurement of the hardness of the water.
Further, the control method of the present invention, in case that the
washing machine is operated four times or more, calculates and stores the
cumulative mean of the hardnesses of water in the plural operations of the
washing machine except for the maximum and minimum hardnesses of water
so that the hardness abnormally higher or lower than the general hardness is
excluded, thereby obtaining accurate measurement of the hardness of the
water.
Moreover, the control method of the present invention, in case that the
washing machine is operated times corresponding to a predetermined
frequency or more, calculates and stores the running mean of the hardnesses of
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water in the plural operations of the washing machine so that the recent
hardnesses of water while excluding the previous hardnesses of water a few
months ago are considered, thereby obtaining accurate measurement of the
hardness of the water.
Brief Description of the Drawings
The above and other objects, features and other advantages of the
present invention will be more clearly understood from the following detailed
description taken in conjunction with the accompanying drawings, in which:
Fig. 1 is a longitudinal-sectional view of a washing machine for
performing a control method in accordance with the present invention;
Fig. 2 is a block diagram of the washing machine for performing the
control method in accordance with the present invention;
Fig. 3 is a partially-exploded perspective view of a sensor assembly of
the washing machine of Fig. 1;
Fig. 4 is an enlarged cross-sectional view of the sensor assembly of the
washing machine of Fig. 1;
Figs. 5a and 5b are flow charts illustrating a control method of a
washing machine in accordance with a first embodiment of the present
invention;
Figs. 6a and 6b are flow charts illustrating a control method of a
washing machine in accordance with a second embodiment of the present
invention;
Figs. 7a and 7b are flow charts illustrating a control method of a
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washing machine in accordance with a third embodiment of the present
invention;
Figs. 8a and 8b are flow charts illustrating a control method of a
washing machine in accordance with a fourth embodiment of the present
invention; and
Figs. 9a and 9b are flow charts illustrating a control method of a
washing machine in accordance with a fifth embodiment of the present
invention.
Best Mode for Carrying Out the Invention
Now, preferred embodiments of the present invention will be
described in detail with reference to the annexed drawings.
Fig. 1 is a longitudinal-sectional view of a washing machine for
performing a control method in accordance with the present invention, and
Fig. 2 is a block diagram of the washing machine for performing the control
method in accordance with the present invention.
For reference, a washing machine for performing a control method in
accordance with the present invention is not limited to an upright-type
washing machine as shown in Fig. 1, but may be applied to all kinds of
washing machines including drum-type washing machines.
The washing machine shown in Fig. 1 comprises a cabinet 1 defining
the external appearance of the washing machine, an outer tub 10 suspended
by a supporting member 2 in the cabinet 1 for containing water therein, an
inner tub 28 rotatably installed in the outer tub 10 and provided with a wash
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vane 26 installed on the bottom surface thereof, a motor 30 placed under the
outer tub 6 for rotating the wash vane 26 or the inner tub 28, a power
transmission gear 40 for transmitting driving force of the motor 30 to the
wash vane 26 or the inner tub 28, and a microcomputer 50 for controlling the
operation of the washing machine.
A top cover 3 constituting the upper part of the washing machine is
placed on the upper end of the cabinet 1.
An opening 4 for putting and taking clothes into and out of the washing
machine therethrough is formed through the central portion of the top cover 3,
and a lead 5 for opening and closing the opening 4 is rotatably connected to one
side of the top cover 3.
A water supply valve 6, for intermitting water supplied through an
external hose, and a detergent box 7, for containing a detergent so that the
water having passed through the water supply valve 6 is mixed with the
detergent and the obtained mixture is supplied to the inner tub 28 or the outer
tub 20, are installed on the rear part of the top cover 3.
The microcomputer 50 is installed in the front part of the top cover 3,
and a control panel 8 for allowing a user to manipulate the washing machine
therethrough is placed on the front part of the top cover 3.
Legs, which are protruded from the lower surface of the cabinet 1, are
mounted on a base 9 supporting the cabinet 1.
A drain valve 11 for intermitting water discharge is installed on the
lower part of the outer tub 10, and a drain hose 12 for guiding the water having
passed through the drain valve to the outside of the washing machine is
connected to the drain valve 11.
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An air chamber 13 communicating with the outer tub 10 is installed at
one side of the outer tub 10.
An air tube 14 for compressing air, when the water is supplied to the
air chamber 13, is connected to the upper part of the air chamber 13, and a
pressure sensor 15 for sensing the pressure in the air tube 14 is connected to the
air tube 14.
The pressure sensor 15 outputs a signal to the microcomputer 50, and
the microcomputer 50 senses a water level based on the signal outputted from
the pressure sensor 15.
A sensor assembly 16 for sensing temperature and conductivity of
water is installed on the lower end of the air chamber 13.
The sensor assembly 16 senses conductivity and temperature of water,
in which the detergent is not dissolved, or conductivity and temperature of
water, in which the detergent is dissolved, and thus outputs a corresponding
signal to the microcomputer 50. Then, the microcomputer 50 sets a washing
pattern, including washing intensity, supplied water level, washing time, rinsing
frequency, rinsing time, dehydrating time, etc., based on the signal outputted
from the sensor assembly 16.
Here, the washing intensity is adjusted by varying the rotational speed
(rpm) of the wash vane 26 or the inner tub 28 or by rotating the wash vane 26
or the inner tub 28.
The motor 30 includes a stator fixed to the lower surface of the outer
tub 10, a rotor rotated by the magnetic action with the stator, and a hall sensor
32 for sensing the rotational speed (rpm) or rotational angle of the rotor.
The hall sensor 32 outputs a signal to the microcomputer 50, and the
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microcomputer 50 senses the quantity of clothes based on the signal outputted
from the hall sensor 32.
The microcomputer 50 stores a plurality of tables for determining the
quantity of the detergent corresponding to the hardness of the water. Thus,
the microcomputer 50 selects one out of the stored tables based on the hardness
of the water, and then determines the quantity of the detergent from the
conductivity and temperature of the water, in which the detergent is dissolved.
In Fig. 2, reference numeral 60 denotes a washing pattern display, such
as an LCD or an LED, for displaying the washing pattern of the washing
machine to the outside.
Further, reference numeral 62 denotes a sensor operation display, such
as an LCD or an LED, for displaying the sensing operation of the sensor
assembly 16 to the outside.
Fig. 3 is a partially-exploded perspective view of the sensor assembly
16 shown in Fig. 1, and Fig. 4 is an enlarged cross-sectional view of the sensor
assembly 16 shown in Fig. 1.
As shown in Figs. 3 and 4, the sensor assembly 16 includes a
conductivity sensor 17 having a pair of conductivity electrodes separated from
each other, a temperature sensor 18 having a temperature electrode for
sensing a temperature, a housing 19 inserted into the air chamber 13,
provided with an opened lower surface, and having a pair of through holes
19A and 19B passing the conductivity electrodes formed on the upper surface
thereof and a protrusion 19C surrounding the temperature electrode, a cover
20 passing lower portions of the conductivity electrodes and the temperature
electrode and attached to the lower surface of the housing 19, and a filling
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material 21 filling a space formed between the housing 19 and the cover 20.
A connector 24 provided with a plurality of electric wires 22 and 23 is
attached to and detached from the cover 20 so that the sensor assembly 16
and the microcomputer communicate signals with each other.
The connector 24 includes a receptacle housing 25 attached to and
detached from the cover 20, and a plurality of receptacles 26 and 27 provided
with ends connected to the electric wires 22 and 23 and the other ends
attached to and detached from the conductivity electrodes and the
temperature electrode.
Figs. 5a and 5b are flow charts illustrating a control method of a
washing machine in accordance with a first embodiment of the present
invention;
As shown in Fig. 5a, in the control method of the washing machine in
accordance with the first embodiment of the present invention, when power
and instructions for operating the washing machine are inputted to the
washing machine through the control panel 8, the microcomputer 50
determines whether or not the washing machine is in an initial operation (SI
and S2).
In case that it is determined that the washing machine is in the initial
operation, the microcomputer 50 loads a standard hardness, which was
inputted to the microcomputer 50 in advance. On the other hand, in case
that it is determined that the washing machine is not in the initial operation,
the microcomputer 50 loads the hardness of the water stored in the previous
operation (S3 and S4).
Thereafter, the microcomputer 50 senses the quantity of clothes
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placed in the washing machine (S5).
Here, the microcomputer 50 rotates the motor 30 so that a pulsator or
the inner tub 28 is agitated in a short period of time or rotated once, and
measures time, taken to agitate the pulsator or the inner tub 28 or to rotate
the pulsator or the inner tub 28 once, or surplus rotating angle from a signal
outputted from the hall sensor 32, thereby being capable of sensing the
quantity of clothes. Other sensing methods except for the above-described
sensing method may be applied to the present invention.
The microcomputer 50 sets a washing pattern based on the sensed
quantity of clothes (S6).
Here, preferably, the washing pattern includes all factors regarding
the operation of the washing machine, such as washing intensity, supplied
water level, washing time, rinsing frequency, rinsing time, dehydrating time,
etc. Hereinafter, for convenience of description, the washing pattern is limited
to washing intensity, supplied water level, washing time, rinsing frequency,
rinsing time, and dehydrating time.
After the microcomputer 50 sets the washing pattern, the
microcomputer 50 outputs a control signal to the washing pattern display 60 so
that all the factors or only the washing, rinsing and dehydrating times of the set
washing pattern are displayed by the washing pattern display 60 to the outside
(S7).
The microcomputer 50 turns on the water supply valve 6 so that water
is supplied to a first water level of the set washing pattern (S8).
When the water supply valve 6 is turned on, the water passes through
the detergent box 7, the detergent contained in the detergent box 7 is dissolved
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in the water, and the obtained mixture is supplied to the inner tub 28 or the
outer tub 10. When the mixture of the water and the detergent is supplied to
the first water level, the microcomputer 50 turns off the water supply valve 6.
The microcomputer 50 operates the motor 30 during a first washing
time of the set washing pattern.
A rotary current is generated in the inner tub 28, thereby performing a
washing operation (S9).
Thereafter, after the first washing time has elapsed, the microcomputer
50 turns on the water supply valve 6 so that water is supplied to a second water
level of the set washing pattern (S10).
When the water supply valve 6 is turned on, new water is supplied to
the inner tub 28 or the outer tub 10 so that the inner tub 28 or the outer tub 10
contains a larger quantity of water. When the water is supplied to the second
water level, the microcomputer 50 turns off the water supply valve 6.
Thereafter, the microcomputer 50 operates the motor 30 during a
second washing time of the set washing pattern.
Here, the microcomputer 50 rotates the motor 30 in regular and
opposite directions so that the clothes contained in the inner tub 28 are agitated
to improve solubility of the detergent in the water (Sll).
After the second washing time has elapsed, the microcomputer 50
selects one table out of a plurality of tables storing the quantity of the detergent
corresponding to the loaded hardness of the water, outputs a signal to the
conductivity sensor 17 and the temperature sensor 18 so that the conductivity
sensor 17 and the temperature sensor 18 measure the conductivity and the
temperature of the water containing the detergent dissolved therein, and
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during the measurement, switches on or off the sensor operation display 62
(S12).
The microcomputer 50 calculates the quantity of the detergent using
the selected table based on the measured conductivity and temperature of the
water containing the detergent dissolved therein (S13).
Then, the microcomputer 50 resets the washing pattern based on the
calculated quantity of the detergent (S14).
Here, the microcomputer 50 may reset all or several factors of the
washing pattern, which were initially set.
The microcomputer 50 outputs a control signal to the washing pattern
display 60 so that all the factors or only the residual washing, rinsing and
dehydrating times of the reset washing pattern are displayed by the washing
pattern display 60 to the outside (S15).
The microcomputer 50 operates the motor 30 during a third washing
time of the reset washing pattern, and, after the third washing time has elapsed,
stops the operation of the motor 30, thereby completing the washing operation
(S16).
Thereafter, the microcomputer 50 turns on the drain valve 11 to
discharge water contaminated during the washing operation to the outside of
the washing machine, and, after the discharge of the contaminated water is
completed, turns off the drain valve 11 (S17).
Then, the microcomputer 50 operates the motor 30 and the power
transmission gear 40 in a dehydration mode, thereby dehydrating the clothes in
the washing machine (S18).
As shown in Fig. 5b, the microcomputer 50 repeats water supply, rinse,
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drain and dehydration times corresponding to a rinsing frequency of the reset
washing pattern.
Here, for convenience of description, the rinsing frequency is reset to
three times.
The microcomputer 50 turns on the water supply valve 6 so that water
is supplied to a third water level of the reset washing pattern (S19).
When the water supply valve 6 is turned on, the water passes through
the detergent box 7, the detergent contained in the detergent box 7 is dissolved
in the water, and the obtained mixture is supplied to the inner tub 28 or the
outer tub 10. When the mixture of the water and the detergent is supplied to
the third water level, the microcomputer 50 turns off the water supply valve 6.
The microcomputer 50 operates the motor 30 during a first rinsing
time of the reset washing pattern.
A rotary current is generated in the inner tub 28, thereby performing a
rinsing operation (S20).
Thereafter, after the first rinsing time has elapsed, the microcomputer
50 turns on the drain valve 11 so that water contaminated during the rising
operation is discharged to the outside of the washing machine, and, after the
discharge of the contaminated water is completed, turns off the drain valve 11
(S21).
Then, the microcomputer 50 operates the motor 30 and the power
transmission gear 40 in the dehydration mode, thereby dehydrating the clothes
in the washing machine (S22).
Thereafter, the microcomputer 50 turns on the water supply valve 6 so
that water is supplied to a fourth water level of the reset washing pattern (S23).
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When the water supply valve 6 is turned on, the water passes through
the detergent box 7, the detergent contained in the detergent box 7 is dissolved
in the water, and the obtained mixture is supplied to the inner tub 28 or the
outer tub 10. When the mixture of the water and the detergent is supplied to
the fourth water level, the microcomputer 50 turns off the water supply valve 6.
The microcomputer 50 operates the motor 30 during a second rinsing
time of the reset washing pattern.
A rotary current is generated in the inner tub 28, thereby performing
the rinsing operation (S24),
Thereafter, after the second rinsing time has elapsed, the
microcomputer 50 turns on the drain valve 11 so that water contaminated
during the rising operation is discharged to the outside of the washing machine,
and, after the discharge of the contaminated water is completed, turns off the
drain valve 11 (S25).
Then, the microcomputer 50 operates the motor 30 and the power
transmission gear 40 in the dehydration mode, thereby dehydrating the clothes
in the washing machine (S26).
Thereafter, the microcomputer 50 turns on the water supply valve 6 so
that water is supplied to a fifth water level of the reset washing pattern (S27).
When the water supply valve 6 is turned on, the water passes through
the detergent box 7, the detergent contained in the detergent box 7 is dissolved
in the water, and the obtained mixture is supplied to the inner tub 28 or the
outer tub 10. When the mixture of the water and the detergent is supplied to
the fifth water level, the microcomputer 50 turns off the water supply valve 6.
The microcomputer 50 operates the motor 30 during a third rinsing
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time of the reset washing pattern.
The microcomputer 50 is rotatably agitated for a designated time (for
example, 1 minute) of the third rinsing time (for example, 3 minutes) so that
accuracy in calculating the hardness of the water, which will be described later,
is improved.
After the designated time (for example, 1 minute) of the third rinsing
time (for example, 3 minutes) has elapsed, the microcomputer 50 outputs a
signal to the conductivity sensor 17 and the temperature sensor 18 so that the
conductivity sensor 17 and the temperature sensor 18 measure the conductivity
and the temperature of the water (S28 and S29).
The microcomputer 50 calculates the hardness of the water using a
designated equation or a table for determining the hardness of the water based
on the measured conductivity and temperature of the water (S30).
The microcomputer 50 stores the calculated hardness of the water in
an EEPROM (S31).
Then, the microcomputer 50 continuously operates the motor 30 for
the residual time (for example, 2 minutes) of the third rinsing time (for
example, 3 minutes), and a rotary current is generated in the inner tub 28,
thereby performing the rinsing operation (S32).
After the third rinsing time has elapsed, the microcomputer 50 turns
on the drain valve 11 so that water contaminated during the rising operation is
discharged to the outside of the washing machine, and, after the discharge of
the contaminated water is completed, turns off the drain valve 11 (S33).
Then, the microcomputer 50 operates the motor 30 and the power
transmission gear 40 in the dehydration mode, thereby dehydrating the clothes
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in the washing machine ($34).
Figs. 6a and 6b are flow charts illustrating a control method of a
washing machine in accordance with a second embodiment of the present
invention.
The control method of the washing machine in accordance with the
second embodiment as shown in Figs. 6a and 6b differs from the control
method of the washing machine in accordance with the first embodiment in
that the initial washing pattern is not set based on the quantity of clothes
contained in the washing machine. That is, the hardness of the water, which
was calculated in the previous operation and stored, is applied to a designated
equation or a separate table (S5'), and thus an initial washing pattern is set
(S6'). Other steps except for the step of setting the initial washing pattern
are substantially the same as those of the first embodiment and are thus
denoted by the same reference numerals, and detailed descriptions thereof
will be omitted because they are considered to be unnecessary.
That is, in case that hardness of the water, which was calculated in
the previous operation and stored, is comparatively high, at least one factor
out of washing pattern, such as washing intensity, supplied water level, washing
time, rinsing frequency, rinsing time, and dehydrating time, is set to high, and
in case that hardness of the water, which was calculated in the previous
operation and stored, is comparatively low, at least one factor out of washing
pattern, such as washing intensity, supplied water level, washing time, rinsing
frequency, rinsing time, and dehydrating time, is set to low. Further, the
washing pattern is reset based on the quantity of the detergent, which was
measured during the washing operation, and the washing machine is operated
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according to the reset washing pattern.
The above-described control method of the washing machine in
accordance with the second embodiment of the present invention does not
require a step for sensing the quantity of clothes, thus reducing energy
necessary to sense the quantity of clothes and shortening an overall washing
time.
Figs, 7a and 7b are flow charts illustrating a control method of a
washing machine in accordance with a third embodiment of the present
invention.
In the control method of the washing machine in accordance with the
third embodiment as shown in Figs. 7a and 7b, in case that the washing
machine has been operated plural times, the cumulative mean of hardnesses
of water calculated in operations of the washing machine is calculated, and
the calculated cumulative mean is stored for the next operation of the washing
machine (S31'). Other steps except for the step of calculating the cumulative
mean are substantially the same as those of the first embodiment and are thus
denoted by the same reference numerals, and detailed descriptions thereof
will be omitted because they are considered to be unnecessary.
That is, as shown in Equation 1 below, the cumulative mean of the
hardnesses of water is calculated by adding the hardnesses of water, which
were calculated in the previous operations and stored, and the hardness of the
water, which is calculated in the present operation, and by dividing the added
value by the total operating frequencies (N) of the washing machine.
[Equation 1]
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As described above, the control method of the washing machine in
accordance with the third embodiment stores the cumulative mean of the
hardnesses of water calculated in plural operations of the washing machine,
thus reducing the variation of the hardness of the water and obtaining more
accurate measurement of the hardness of the water, compared to the other
control methods, which store only the hardness of the water calculated in the
previous operation just before the present operation of the washing machine.
Figs. 8a and 8b are flow charts illustrating a control method of a
washing machine in accordance with a fourth embodiment of the present
invention.
In the control method of the washing machine in accordance with the
fourth embodiment as shown in Figs. 8a and 8b, in case that the washing
machine has been operated plural times, the cumulative mean of hardnesses
of water calculated in operations of the washing machine except for the
maximum and minimum hardnesses of water is calculated, and the calculated
cumulative mean is stored for the next operation of the washing machine
(S31"). Other steps except for the step of calculating the cumulative mean of
the hardnesses of water except for the maximum and minimum hardnesses
are substantially the same as those of the first embodiment and are thus
denoted by the same reference numerals, and detailed descriptions thereof
will be omitted because they are considered to be unnecessary.
That is, as shown in Equation 2 below, the cumulative mean of the
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hardnesses of water is calculated by adding the hardnesses of water (H2, H3
and H4), which were calculated in the previous operations and the present
operation, except for the maximum hardness (H5) and the minimum hardness
(HI) and by dividing the added value (H2+H3+H4) by the value obtained by
subtracting 2 from the total operating frequencies (N) of the washing
machine.
[Equation 2]

In case that the operating frequency (N) of the washing machine is less
than 4, it is preferable that the simple cumulative mean is calculated in the
same manner as the third embodiment of the present invention.
As described above, the control method of the washing machine in
accordance with the fourth embodiment excludes the hardness abnormally
higher or lower than the general hardness, thereby obtaining accurate
measurement of the hardness of the water.
Figs. 9a and 9b are flow charts illustrating a control method of a
washing machine in accordance with a fifth embodiment of the present
invention.
In the control method of the washing machine in accordance with the
fifth embodiment as shown in Figs. 9a and 9b, in case that the washing
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machine has been operated plural times, a predetermined frequency (a) is
stored in the microcomputer 50, and is compared to the operating frequency
(N) of the washing machine. Only in case that the operating frequency (N) of
the washing machine is larger than the predetermined frequency (a), the
running mean is stored (S31'"). Other steps except for the step of storing the
running mean of the hardnesses of water are substantially the same as those
of the first embodiment and are thus denoted by the same reference numerals,
and detailed descriptions thereof will be omitted because they are considered
to be unnecessary.
That is, when the operating frequency (N) of the washing machine
reaches the predetermined frequency (a), as shown in Equation 3 below, the
running mean of the hardnesses of water is calculated by adding only the
recent hardnesses of water (H5, H6, ... and HN), which correspond to the
predetermined frequency and dividing the added value (H5+H6+...+HN) by
the predetermined frequency (a).

Here, the residual hardnesses of water, which are not used to calculate
the running mean, are deleted.
On the other hand, in case that the operating frequency (N) of the
washing machine is not larger than the predetermined frequency (a), it is
preferable that the cumulative mean is calculated and stored in the same
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manner as the second and third embodiments.
As described above, the control method of the washing machine in
accordance with the fifth embodiment does not increase the quantity of data to
be processed more than a designated limit, thus eliminating the limit of storage
capacity and processing capacity of an EEPROM generated when the
cumulative mean is calculated. Further, the control method of the washing
machine in accordance with the fifth embodiment considers the recent
hardnesses of water while excluding the previous hardnesses of water a few
months ago, thus obtaining accurate measurement of the hardness of the water.
Industrial Applicability
As apparent from the above description, the present invention
provides a control method of a washing machine, in which hardness of the
water calculated in the previous operation of the washing machine is used to
set a washing pattern of the present operation of the washing machine in
consideration of different characteristics of water by regional groups, thereby
having optimum washing and rinsing capacities and minimizing water and
energy consumption.
The control method of the present invention displays a variation in
the washing pattern to users in real time, thereby providing convenience and
utility of the washing machine to the users.
The control method of the present invention calculates hardness of
the water, from which a detergent is completely removed, in a final rinsing
operation of the present operation of the washing machine, thereby being
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capable of calculating the accurate quantity of the detergent for the next
operation of the washing machine, not requiring a separate step for
calculating the hardness of the water, and reducing the overall washing time.
The control method of the present invention, in case that the washing
machine is operated plural times, calculates and stores the cumulative mean
of the hardnesses of water in the plural operations of the washing machine,
thereby reducing the variation of the hardness of the water and obtaining more
stable and accurate measurement of the hardness of the water.
Further, the control method of the present invention, in case that the
washing machine is operated four times or more, calculates and stores the
cumulative mean of the hardnesses of water in the plural operations of the
washing machine except for the maximum and minimum hardnesses of water
so that the hardness abnormally higher or lower than the general hardness is
excluded, thereby obtaining accurate measurement of the hardness of the
water.
Moreover, the control method of the present invention, in case that the
washing machine is operated times corresponding to a predetermined
frequency or more, calculates and stores the running mean of the hardnesses of
water in the plural operations of the washing machine so that the recent
hardnesses of water while excluding the previous hardnesses of water a few
months ago are considered, thereby obtaining accurate measurement of the
hardness of the water.
Although the preferred embodiments of the present invention have
been disclosed for illustrative purposes, those skilled in the art will appreciate
that various modifications, additions and substitutions are possible, without
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departing from the scope and spirit of the invention as disclosed in the
accompanying claims.
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PCTYKR2004/001256
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Claims:
1. A control method of a washing machine comprising the steps of:
(a) setting a present washing pattern in consideration of the hardness
of the water calculated and stored in the previous operation of the washing
machine;
(b) operating the washing machine based on the set present washing
pattern; and
(c) calculating and storing the hardness of the water in the present
operation of the washing machine for setting a next washing pattern for the
next operation of the washing machine.
2. The control method as set forth in claim 1,
wherein the hardness of the water stored in the previous operation of
the washing machine is automatically loaded when power is inputted to the
washing machine.
3. The control method as set forth in claim 1,
wherein the hardness of the water in the present operation of the
washing machine is calculated after water in the washing machine is agitated
for a predetermined time or more.
4. The control method as set forth in claim 1, wherein step (c) includes
the sub-steps of:
(c-1) measuring temperature and conductivity of the water; and
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(c-2) calculating the hardness of the water based on the temperature
and conductivity of the water measured in sub-step (c-1).
5. The control method as set forth in claim 4,
wherein sub-step (c-1) is performed a predetermined time before a
final rinsing operation is completed.
6. The control method as set forth in claim 1,
wherein the washing pattern includes at least one of washing
intensity, supplied water level, washing time, rinsing frequency, rinsing time,
and dehydrating time.
7. The control method as set forth in claim 1,
wherein in step (a), in case that the washing machine is in an initial
operation, the washing pattern is set based on an already-inputted standard
hardness of the water.
8. The control method as set forth in claim 1,
wherein in step (c), in case that the washing machine is operated plural
times, the cumulative mean of the hardnesses of water in the plural operations
of the washing machine is calculated and stored.
9. The control method as set forth in claim 1,
wherein in step (c), in case that the washing machine is operated four
times or more, the cumulative mean of the hardnesses of water in the plural
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operations of the washing machine except for the maximum and minimum
hardnesses of water is calculated and stored.
10. The control method as set forth in claim 1,
wherein in step (c), in case that the washing machine is operated times
corresponding to a predetermined frequency or more, the running mean of the
hardnesses of water in the plural operations of the washing machine is
calculated and stored.
11. The control method as set forth in claim 1,
wherein the set present washing pattern is displayed so that it is
recognized by users.
12. A control method of a washing machine comprising the steps of:
(I) sensing the quantity of clothes after instructions for operating the
washing machine are inputted to the washing machine, and setting a washing
pattern based on the sensed quantity of clothes;
(II) supplying water based on the washing pattern set in step (I), and
dissolving a detergent in the water;
(III) measuring conductivity and temperature of the water containing
the detergent, calculating the quantity of the detergent in consideration of the
hardness of the water calculated and stored in the previous operation of the
washing machine, and resetting the washing pattern based on the calculated
quantity of the detergent; and
(IV) performing a washing or rinsing operation based on the reset
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PCT/KR2004/001256
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washing pattern, and calculating and storing the hardness of the water in a
final rising operation.
13. A control method of a washing machine comprising the steps of:
(I) setting a washing pattern based on the hardness of the water
calculated and stored in the previous operation of the washing machine after
instructions for operating the washing machine are inputted to the washing
machine;
(II) supplying water based on the washing pattern set in step (I), and
dissolving a detergent in the water;

(III) measuring conductivity and temperature of the water containing
the detergent, calculating the quantity of the detergent in consideration of the
hardness of the water calculated and stored in the previous operation of the
washing machine, and resetting the washing pattern based on the calculated
quantity of the detergent; and
(IV) performing a washing or rinsing operation based on the reset
washing pattern, and calculating and storing the hardness of the water in a
final rising operation.
14. The control method as set forth in claim 12 or 13,
wherein in step (I), washing, rinsing and dehydrating times of the set
washing pattern are displayed so that they are recognized by users.
15. The control method as set forth in claim 12 or 13,
wherein in step (III) the conductivity and temperature of the water
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containing the detergent dissolved therein are displayed to the outside
through a sensor operation display so that they are recognized by users
during the measurement thereof.
16. The control method as set forth in claim 12 or 13,
wherein in step (III), one table is selected from a plurality of tables
containing quantities of the detergent according to hardnesses of water, and
the quantity of the detergent corresponding to the conductivity and
temperature of the water containing the detergent dissolved therein is
calculated from the selected table.
17. The control method as set forth in claim 12 or 13,
wherein in step (III), in case that the washing machine is in an initial
operation, the washing pattern is set based on an already-inputted standard
hardness of the water.
18. The control method as set forth in claim 12 or 13, wherein step
(IV) includes the sub-steps of:
(i) measuring temperature and conductivity of the water in a final
rinsing operation; and
(ii) calculating the hardness of the water based on the temperature
and conductivity of the water measured in sub-step (i).
19. The control method as set forth in claim 18,
wherein sub-step (i) is performed after water in the washing machine
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is agitated for a predetermined time or more.
20. The control method as set forth in claim 18,
wherein sub-step (i) is performed a predetermined time before a final
rinsing operation is completed.
21. The control method as set forth in claim 12 or 13,
wherein in step (IV), residual washing, rinsing and dehydrating times
changed by the reset washing pattern are displayed.
22. The control method as set forth in claim 12 or 13,
wherein in step (IV), in case that the washing machine is operated
plural times, the cumulative mean of the hardnesses of water in the plural
operations of the washing machine is calculated and stored.
23. The control method as set forth in claim 12 or 13,
wherein in step (c), in case that the washing machine is operated four
times or more, the cumulative mean of the hardnesses of water in the plural
operations of the washing machine except for the maximum and minimum
hardnesses of water is calculated and stored.
24. The control method as set forth in claim 12 or 13,
wherein in step (c), in case that the washing machine is operated times
corresponding to a predetermined frequency or more, the running mean of the
hardnesses of water in the plural operations of the washing machine is
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calculated and stored.
34

Disclosed is a control method of a washing machine comprising the steps of (a) setting a washing pattern in the present operation of the washing machine in consideration of hardness of the water calculated in the previous operation of the washing machine, (b) operating the washing machine based on the set washing pattern, and (c) calculating and storing hardness of the water in the present operation of the washing machine to set a next washing pattern in the next operation of the washing machine, thereby having the optimum washing or rinsing capacity of the washing machine in consideration of different characteristics of water by regional groups.

Documents:

02385-kolnp-2005-abstract.pdf

02385-kolnp-2005-claims.pdf

02385-kolnp-2005-description complete.pdf

02385-kolnp-2005-drawings.pdf

02385-kolnp-2005-form 1.pdf

02385-kolnp-2005-form 3.pdf

02385-kolnp-2005-form 5.pdf

02385-kolnp-2005-international publication.pdf

2385-kolnp-2005-abstract.pdf

2385-KOLNP-2005-AMENDED PAGES.pdf

2385-kolnp-2005-claims.pdf

2385-KOLNP-2005-CORRESPONDENCE-1.1.pdf

2385-KOLNP-2005-CORRESPONDENCE.pdf

2385-kolnp-2005-description complete.pdf

2385-kolnp-2005-drawings.pdf

2385-kolnp-2005-form 1.pdf

2385-kolnp-2005-form 3.pdf

2385-KOLNP-2005-FORM-27.pdf

2385-kolnp-2005-gpa.pdf

2385-kolnp-2005-granted-abstract.pdf

2385-kolnp-2005-granted-claims.pdf

2385-kolnp-2005-granted-correspondence.pdf

2385-kolnp-2005-granted-description (complete).pdf

2385-kolnp-2005-granted-drawings.pdf

2385-kolnp-2005-granted-examination report.pdf

2385-kolnp-2005-granted-form 1.pdf

2385-kolnp-2005-granted-form 18.pdf

2385-kolnp-2005-granted-form 3.pdf

2385-kolnp-2005-granted-form 5.pdf

2385-kolnp-2005-granted-gpa.pdf

2385-kolnp-2005-granted-reply to examination report.pdf

2385-kolnp-2005-granted-specification.pdf

2385-kolnp-2005-others.pdf

2385-kolnp-2005-petition under rule 137.pdf

2385-kolnp-2005-reply to examination report-1.1.pdf

2385-kolnp-2005-reply to examination report.pdf

abstract-02385-kolnp-2005.jpg


Patent Number 239056
Indian Patent Application Number 2385/KOLNP/2005
PG Journal Number 10/2010
Publication Date 05-Mar-2010
Grant Date 03-Mar-2010
Date of Filing 25-Nov-2005
Name of Patentee LG ELECTRONICS, INC.
Applicant Address 20, YEOEUIDO-DONG, YOUNGDEUNGPO-GU, SEOUL
Inventors:
# Inventor's Name Inventor's Address
1 PARK, SEOK KYU #107-1203, DAEDONG HWANGTOBANG APT. DAEBANG-DONG, CHANGWON-SI, KYUNGSANGNAM 641-901
2 CHUNG, BO SUN 3/3 #200-5, DONGDAESINDONG 1-GA, SEO-KU, PUSAN 602-808
3 GO, SEOG HO #406-1306, BUYOUNG E-GRIM, 7TH APT. JELMI VILLAGE, GWANDONG-RI, JANGYU-MYUN, KIMHAE-SI, KYUNGSANGNAM-DO, 621-831
4 KIM, YOUNG SOO #43-5, YONGHO-DONG, CHANGWON-SI, KYUNGSANGNAM-DO, 641-840
PCT International Classification Number D06F 33/02
PCT International Application Number PCT/KR2004/001256
PCT International Filing date 2004-05-28
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10-2003-0040673 2003-06-23 Republic of Korea
2 10-2003-0334002 2003-05-28 Republic of Korea
3 10-2003-0054634 2003-08-07 Republic of Korea