U.S. patent application number 12/958059 was filed with the patent office on 2011-06-02 for washing machine and a method of controlling the same.
This patent application is currently assigned to LG ELECTRONICS INC.. Invention is credited to Youngjong KIM, Sangjun LEE.
Application Number | 20110126359 12/958059 |
Document ID | / |
Family ID | 44067757 |
Filed Date | 2011-06-02 |
United States Patent
Application |
20110126359 |
Kind Code |
A1 |
KIM; Youngjong ; et
al. |
June 2, 2011 |
WASHING MACHINE AND A METHOD OF CONTROLLING THE SAME
Abstract
Provided are a washing machine and a method of controlling the
washing machine. The method includes measuring a time required for
an amount of washing water supplied to a washing tub to reach a
predetermined reference amount, determining a water pressure of the
washing water in accordance with the measured time, and varying a
water supply time in accordance with the determined water pressure.
The water supply time can be adjusted according to the water
pressure, it can be prevented that the washing performance is
varied whenever the wash water is varied. Thus, the washing
performance can be improved regardless of the water pressure.
Inventors: |
KIM; Youngjong;
(Changwon-si, KR) ; LEE; Sangjun; (Changwon-si,
KR) |
Assignee: |
LG ELECTRONICS INC.
Seoul
KR
|
Family ID: |
44067757 |
Appl. No.: |
12/958059 |
Filed: |
December 1, 2010 |
Current U.S.
Class: |
8/137 ;
68/12.01 |
Current CPC
Class: |
D06F 35/006 20130101;
D06F 33/00 20130101 |
Class at
Publication: |
8/137 ;
68/12.01 |
International
Class: |
D06L 1/20 20060101
D06L001/20; D06F 33/00 20060101 D06F033/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 2, 2009 |
KR |
10-2009-0118525 |
Claims
1. A method of controlling a washing machine, the method comprises:
measuring a time required for an amount of washing water supplied
to a washing tub to reach a predetermined reference amount;
determining a water pressure of the washing water in accordance
with the measured time; and varying a water supply time in
accordance with the determined water pressure.
2. The method of claim 1, wherein data on a spraying time required
for an amount of washing water to reach the predetermined reference
amount and a water pressure of the washing water are stored in a
reference table in advance.
3. The method of claim 1, in the determining of the present water
pressure, a water pressure of washing water supplied in the present
compares with the water pressure stored in the reference table.
4. The method of claim 1, wherein the water supply time is
increased when the determined water pressure is less than a
predetermined reference water pressure.
5. The method of claim 1, wherein the water supply time is reduced
when the determined pressure is greater than a predetermined
reference water pressure.
6. The method of claim 1, wherein the water supply time is set to
be in reverse proportion to the water pressure.
7. The method of claim 1, wherein a washing water level
corresponding to an amount of the laundry loaded in the washing tub
is preset, wherein the water supply time is set in accordance with
the washing water level.
8. The method of claim 7, wherein the water supply time is set by
increasing or reducing the water supply, which is preset in
accordance with the washing water level, according to variation of
the determined water pressure.
9. The method of claim 7, wherein the water supply time set in
accordance with the washing water level varies and renewed
according to the determined water pressure.
10. The method of claim 1, wherein the predetermined reference
amount is in proportion to an amount of the laundry loaded in the
washing tub.
11. The method of claim 1, wherein the predetermined reference
amount is increased or reduced in accordance with a wash course
selected.
12. A method of controlling a washing machine, the method
comprising: filling washing water by a predetermined reference
amount; measuring a time required for the washing water to be
filled; determining water pressure of the washing water in
accordance with the measured time; determining a spraying time of
the washing water in accordance with the determined water pressure;
perform a wash cycle by spraying the washing water for the
determined spraying time; and perform a rinse cycle by spraying the
washing water for the determined spraying time.
13. A washing machine comprises: a memory comprising a reference
table storing data on a time required for washing water to be
filled in a washing tub by a predetermined reference amount and a
water pressure determined according to the time; and a control unit
for determining the present water pressure of the washing water
with reference to the reference table and varying a spraying time
of the washing time sprayed into the washing tub in accordance with
the determined water pressure.
14. The washing machine of claim 13, wherein the memory further
comprises a spray-time table storing a spraying time of the washing
water according to an amount of laundry.
15. The washing machine of claim 14, wherein the control unit
measures a time required for the washing water to reach a reference
amount and determines the present water pressure by comparing the
measured time with data that is preset in the reference table.
16. The washing machine of claim 14, wherein the control unit
reduces the spraying time stored in the spray-time table as the
water pressure increases.
17. The washing machine of claim 14, wherein the control unit
increases the spraying time stored in the spray-time table as the
water pressure reduces
18. The washing machine of claim 14, wherein the control unit
renews the spray-time table in accordance with the newly determined
water pressure.
19. The washing machine of claim 14, wherein the reference amount
is in proportion to the amount of the laundry loaded in the washing
tub.
20. The washing machine of claim 13, further comprising a water
supply driving unit for supplying the washing water for the
spraying time set by the control unit and a spraying unit for
spraying the washing water into the washing tub according to
operation of the water supply driving unit.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from Korean Patent
Application No. 10-2009-0118525 filed on Dec. 2, 2009 in the Korean
Intellectual Property Office, the disclosure of which is
incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a washing machine and a
method of controlling the same, and more particularly, to a washing
machine and a method of controlling the same, which can prevent
washing performance from varying in accordance with a water
pressure at a place where the washing machine is disposed.
[0004] 2. Description of the Related Art
[0005] In general, a washing machine is a machine that removes
foreign substances from laundry by treating the laundry.
[0006] A process for treating the laundry by the washing machine
includes a process for washing the laundry using washing water in
which detergent is dissolved, a process for rinsing the laundry by
supplying the washing water, which does not contain the detergent,
from an outer side to a washing tub, and a process for removing the
washing water out of the laundry that is washed. The process for
treating the laundry may further include a process for drying the
laundry and a process for discharging the laundry after ironing the
laundry. However, the process for treating the laundry includes a
detergent mixing process, a washing process, a rinsing process, and
a spinning process for removing the water out of the laundry.
[0007] All of the detergent mixing process, washing process,
rinsing process, and spinning process require a process for wetting
the laundry by supplying the washing water into the washing tub.
Generally, the washing water is supplied in a direction from a
cover side toward the washing tub to wet the laundry.
[0008] However, when wetting the laundry by supplying the washing
water in the direction from the cover side toward the washing tub,
it is difficult to evenly wet the laundry in the washing tub. In
order to overcome this limitation, a nozzle method for spraying
high-pressured washing water from the cover side using a nozzle has
been proposed. The nozzle method evenly wets the laundry by
spraying the washing water to the laundry through a narrow water
outlet. However, when spraying the washing water through the
nozzle, an amount of the washing water supplied into the washing
tub varies in accordance with an intensity of the pressure applied
to the nozzle and thus an amount of the washing water sprayed to
the laundry varies. That is, water pressure of a place where the
washing machine is installed is not considered.
[0009] In addition, when the water pressure of the washing water is
high, the washing water sprayed through the nozzle is not directed
toward the laundry but scattered toward an inner surface of the
washing tub. When the water pressure of the washing water is low,
the washing water may not be properly sprayed through the
nozzle.
[0010] Accordingly, a method for constantly maintaining washing
performance by adjusting an amount of the washing water sprayed
from the nozzle and a spraying time considering the water pressure
of the place where the washing machine is installed is
required.
SUMMARY OF THE INVENTION
[0011] An object of the present invention is to provide a washing
machine and a method of controlling the same, which determine a
time for which washing water is sprayed into a washing tub in
accordance with water pressure of a place where the washing machine
is disposed.
[0012] According to an aspect of the present invention, a method of
controlling a washing machine includes measuring a time required
for an amount of washing water supplied to a washing tub to reach a
predetermined reference amount; determining a water pressure of the
washing water in accordance with the measured time; and varying a
water supply time in accordance with the determined water
pressure.
[0013] According to another aspect of the present invention, a
method of controlling a washing machine includes filling washing
water by a predetermined reference amount; measuring a time
required for the washing water to be filled; determining water
pressure of the washing water in accordance with the measured time;
determining a spraying time of the washing water in accordance with
the determined water pressure; perform a wash cycle by spraying the
washing water for the determined spraying time; and perform a rinse
cycle by spraying the washing water for the determined spraying
time.
[0014] According to still another aspect of the present invention,
a washing machine includes a memory including a reference table
storing data on a time required for washing water to be filled in a
washing tub by a predetermined reference amount and a water
pressure determined according to the time; and a control unit for
determining the water pressure of the washing water with reference
to the reference table and varying a spraying time of the washing
time sprayed into the washing tub in accordance with the determined
water pressure.
[0015] According to the aspects of the present invention, since the
time for spraying the washing water is properly adjusted in
accordance with a water pressure of the washing water supplied to
the washing machine, it is possible to sufficiently wet the laundry
even when the water pressure of the washing water is lowered,
thereby providing a proper washing state for the laundry.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The features and advantages of the present invention will
become more apparent from reading the Detailed Description of the
Invention which makes reference to the attached drawings in
which:
[0017] FIG. 1 is a cross-sectional view of a washing machine
according to an embodiment of the present invention;
[0018] FIG. 2 is a reference view illustrating a method of
controlling the washing machine of FIG. 1;
[0019] FIG. 3 is a reference view illustrating a control flow of
the washing machine according to an embodiment of the present
invention;
[0020] FIG. 4 is a reference view illustrating an example of the
spray-time table stored in the memory;
[0021] FIG. 5 is a flowchart illustrating a method of controlling
the washing machine according to an embodiment of the present
invention;
[0022] FIG. 6 is a reference view illustrating an example of a
method of detecting a laundry load;
[0023] FIG. 7 is a reference view illustrating an example of a
spraying unit formed between a cover and a case; and
[0024] FIG. 8 is a reference view illustrating a method of
controlling a washing machine according to another embodiment of
the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0025] The invention is described more fully hereinafter with
reference to the accompanying drawings, in which exemplary
embodiments of the invention are shown. This invention may,
however, be embodied in many different forms and should not be
construed as limited to the exemplary embodiments set forth herein.
Rather, these exemplary embodiments are provided so that this
disclosure is thorough, and will fully convey the scope of the
invention to those skilled in the art. Like reference numerals in
the drawings denote like elements.
[0026] FIG. 1 is a cross-sectional view of a washing machine
according to an embodiment of the present invention.
[0027] Referring to FIG. 1, a washing machine includes a cabinet
10, a top cover 200 that is disposed above the cabinet 10 and
provided with a laundry loading/unloading opening which the laundry
can be loaded and unloaded, a lid assembly 100 that is rotatably
coupled to the top cover to open and close the laundry
loading/unloading opening, and a control panel that provides an
interface so that a user can manipulate the washing machine.
[0028] An outer tub 31 that is hung by a supporting member 20 is
disposed in the cabinet 10 and an inner tub 35 is rotatably
disposed in the outer tub 31.
[0029] In the present invention, when there is no need to
distinguish the outer tub 31 from the inner tub 35 as different
things, the inner and outer tubs 35 and 31 will be referred to as
"washing tub 30" hereinafter. In the present invention, when
describing a wash cycle in which a liquid detergent that is formed
by mixing a detergent with washing water is sprayed, the outer and
inner tubs 31 and 35 will not be described as separate things.
[0030] A damper 25 for absorbing shaking of the outer tub 31, which
is caused by vibration that is generated during rotation of the
inner tub 35, is disposed on a lower end of the supporting member
20. A pulsator 40 for forming a rotational water stream is disposed
on a bottom of the inner 35.
[0031] In addition, a motor 50 that is a driving unit for rotating
the inner tub 35 and the pulsator 40 is disposed under the outer
tub 31. The motor 50 is connected to the inner tub 35 through a
rotational shaft 55 to rotate the inner tub 35. A clutch (not
shown) for selectively transmitting torque of the motor 50 to the
inner tub 35 and the pulsator 40 may be disposed between the inner
tub 35 and the pulsator 40. Accordingly, depending on the operation
of the clutch, only one of the inner tube 35 and the pulsator 40
may rotate or both of the inner tube 35 and the pulsator 40 may
simultaneously rotate.
[0032] Meanwhile, a detergent box 15 for storing the detergent is
detachably disposed on the top cover 200. A water supply hose 70
that is connected to an outer water source to supply washing water
to the detergent box 60 and a water supply valve 75 for controlling
the washing water introduced through the water supply hose 70 are
disposed. When the water supply valve 75 is opened and thus the
washing water is supplied from the outer water source, the washing
water is directed to the detergent box 60, after which the washing
water is supplied to the inner tub 35. The washing water that is
supplied from the detergent box 60 to the inner tub 35 is filled in
the outer tub 31 through a plurality of water holes 36 formed on
the inner tub 35 and the laundry is received in the inner tub
35.
[0033] Further, a drain hose 80 for draining the washing water in
the outer tub 31 to an external side and a drain adjusting valve 85
for controlling the washing water that is being drained through the
drain hose 80, and a drain pump 86 are provided on a lower end of
the outer tub 31.
[0034] FIG. 2 is a reference view illustrating a method of
controlling the washing machine of FIG. 1.
[0035] Referring to FIG. 2, a method of controlling the washing
machine according to an embodiment of the present invention adjust
a time for spraying the washing water toward the laundry with
reference to a water pressure of the washing water introduced into
the washing machine.
[0036] A method of controlling the washing machine according to an
embodiment of the present invention uses a property where, as the
time for introducing a reference amount D-th of the washing water
into the washing tub 30 increases, the water pressure is reduced
and, as the time for introducing the reference amount D-th of the
washing water into the washing tub 30 is reduced, the water
pressure increases.
[0037] Here, the reference amount D-th is determined depending on
an amount of the laundry loaded in the washing tub. If a large
amount of the laundry is loaded in the washing tub 30, the
reference amount D-th of the washing water introduced into the
washing tub 30 increases. On the other hand, when a small amount of
the laundry is loaded in the washing tub 30, the reference amount
D-th of the washing water introduced into the washing tub 30 is
reduced. The reference amount D-th to the amount of the laundry is
defined by a data file provided in the form of a reference table.
The reference table may be recorded in a control unit 210 to be
reprogrammable or may be stored in an external memory (not shown)
connected to the controlled unit 210.
[0038] The control unit 210 measures time required for the amount
of the washing water introduced into the washing tub 30 to reach
the reference amount D-th and determines the water pressure of the
washing water introduced into the washing tub 30 with reference to
the measured time. The water pressure is reduced as the time
required for the amount of the washing water to reach the reference
amount D-th increases. In addition, the water pressure of the
washing water introduced into the washing tub 30 is determined by
an amount of the water supplied to the washing tub 30 per a
predetermined time (e.g., about 10 seconds).
[0039] When the amount of the washing water introduced into the
washing tub 30 reaches the reference amount D-th, the control unit
210 calculates the water pressure of the washing water and
determines the spraying time for spraying the washing water toward
the laundry loaded in the washing tube 30 in accordance with the
calculated water pressure.
[0040] Meanwhile, the memory (not shown) further contains a
spray-time table defining the spraying time of the washing water
into the washing tub 30 in accordance with the amount of the
laundry.
[0041] The control unit 210 renews the time information recorded in
the spray-time table with reference to the water pressure that is
calculated based on the time required for the amount of the washing
water to reach the reference amount D-th. For example, when it is
assumed that the spraying time for spraying the washing water for
about 1 Kg laundry is about 80 sec, the substantial spraying time
may be 90 sec when the water pressure is low and the spraying time
recorded in the spray-time table is renewed from about 80 sec to
about 90 sec to adjust the spraying time of the washing water
toward the laundry in response to the water pressure of the place
where the washing machine is installed.
[0042] FIG. 3 is a block diagram illustrating a control flow of the
washing machine according to an embodiment of the present
invention.
[0043] Referring to FIG. 3, when a user set a washing course and a
washing time by manipulating the control panel 230 after loading
the laundry in the washing tub 30, the control unit 210 determines,
in accordance with the washing course, an amount of the washing
water, an amount of the detergent, a time for rotating the washing
tub 30, and a rotational pattern. According to the determined
conditions, the control unit 210 supplies the detergent into the
washing tub 30, after which the control unit 210 controls a water
supply driving unit 250 to primarily supply the washing water into
the washing tub 30. At this point, the amount of the washing water
supplied to the washing tub 30 is controlled with reference to an
amount detected by a sensor 220. Here, the water supply driving
unit 250 may include a water supply valve.
[0044] The memory 270 has the spray-time table that defines the
time for spraying the washing water into the washing tub 30
according to the amount of the washing water and the amount of the
laundry and the reference table for calculating the water pressure
of the washing water supplied through the water supply driving unit
250.
[0045] The spray-time table defines, in accordance with the amount
of the laundry loaded in the washing tub 30, an amount of the water
that will be supplied to the washing tub 30 and the time for
spraying the washing water to the washing tub 30.
[0046] The reference table indicates a table having the time
required for filling the washing tub with the washing water to the
reference amount according to the amount of the laundry and data on
the water pressure of the washing water or an equation for
calculating the water pressure.
[0047] The control unit 210 determines the amount of the washing
water introduced into the washing tub 30 depending on the amount of
the laundry. Hereinafter, the amount of the washing water, which is
determined depending on the amount of the laundry, will be referred
to as "reference amount." The reference amount is determined when
the laundry is loaded in the washing tub 30.
[0048] The control unit 210 measures time required for the amount
of the washing water introduced into the washing tub 30 to reach
the reference amount and calculates the water pressure based on the
measured time. When the time required for the washing water to
reach the reference amount is short, the water pressure is high. On
the other hand, when the time required for the washing water to
reach the reference amount is long, the water pressure is low. The
reference amount and the water pressure data in accordance with the
time required for the water amount to reach the reference amount
are recorded on the reference table stored in the memory 270. The
control unit determines the water pressure of the washing water
introduced through the water supply driving unit 250 with reference
to the time and water pressure data that are recorded on the
reference table. At this point, the control unit 210 identifies a
time point at which the amount of the washing water reaches the
reference amount through the sensor 220 and applies the identified
time point to the water pressure calculation. Here, the reference
table is recorded on the memory 270 when a manufacturer designs and
manufactures the washing machine.
[0049] The control unit 210 determines the spraying time of the
washing water sprayed into the washing tub 30 with reference to the
water pressure of the washing water introduced into the washing tub
30 through the water supply driving unit 250. The spraying time of
the washing water is determined by varying the time written on the
spray-time table recorded on the memory 270.
[0050] For example, when the water pressure of the washing water
introduced into the washing tub 30 is reduced by 10% and thus the
time for introducing the washing water into the washing tub 30 is
retarded by about 10%. The control unit 210 may increase the time
for spraying the washing water into the washing tub 30 by 10% in
reverse proportion to the reduction of the water pressure by 10%.
At this point, the control unit 210 may renew the spraying time
written on the spray-time table by increasing the spraying time by
about 10%.
[0051] In general, when it is consumed that the water pressure of
the washing water introduced into the washing machine is constant,
the control unit 210 may spray the washing water into the washing
tub 30 and performs the wash cycle using the renewed spray-time
table.
[0052] Needless to say, when the washing machine is installed at a
place where the water pressure frequently varies, the control unit
210 determined the water pressure of the washing water and renews
the spray-time table whenever a laundry treating cycle is
performed.
[0053] Next, the control unit 210 rotates the washing tub 30 or the
pulsator 40 by driving the IPM driver in accordance with the
washing course and washes the laundry using frictional force
generated by the washing tub 30 or the pulsator 40. The IPM driver
is a driver for driving the motor 50. The IPM driver 240 rotates
the motor 50 clockwise or counterclockwise by controlling a voltage
and current applied to the motor 50.
[0054] When the control unit 210 drives the motor 50 by controlling
the IPM driver 240, the control unit 210 drives the motor 50 such
that the motor alternately repeats the clockwise rotation and the
counterclockwise rotation, whereby the washing tub 30 or the
pulsator 40 can alternately repeat the clockwise rotation and the
counterclockwise rotation. As a result, the washing efficiency can
be improved.
[0055] At this point, the control unit 10 may form a rising water
stream in the washing tub 30 by rotating the washing tub 30 or the
pulsator 40 and allows the washing water containing the detergent
to be well mixed with the laundry using the rising water
stream.
[0056] Finally, after the wash cycle by the washing course set by
the user is performed, the control unit 210 drains the washing
water that is fully filled in the washing tub 30 by driving the
drain adjusting valve 85 and the drain pump 86 through the drain
driving unit 250 and supplies new washing water to the washing tub
30 through the water supply driving unit 260, after which the
control unit 210 performs the spinning cycle for the laundry using
the new washing water.
[0057] FIG. 4 is a reference view illustrating an example of the
spray-time table stored in the memory.
[0058] Referring to FIG. 4, the spray-time table has 10 water
amount sections in accordance with the amount (kg) of the laundry
loaded in the washing tub 30. In each section, the amount of the
laundry corresponds to the spraying time of the washing water
sprayed toward the laundry.
[0059] In FIG. 4, the first water amount section is a section
corresponding to the laundry of about 0.3-1.3 kg. In addition, the
spraying time of the washing water in the first water amount
section is set to be about 80 seconds. If the laundry of about 1 kg
is loaded in the washing tub 30, the control unit 210 sprays the
washing water toward the laundry for about 80 seconds.
[0060] The second water amount section corresponds to the laundry
of about 1.6-2.6 kg. Like in the first water amount section, the
spraying time of the washing water in the second water amount
section is about 80 seconds. This is for simplify the algorithm by
applying an identical spraying time for the sections (e.g., the
first and second water amount sections) having similar amount of
the laundry. However, different spraying times may be applied for
the first and second water amount sections and the spray-time table
also defines different spraying times for the respective water
amount sections. In addition, although the water amount sections
includes the first to tenth water amount sections in this
embodiment, the present invention is not limited to this. For
example, the number of the water amount sections may be increased
or reduced in accordance with the maximum amount of the washing
water.
[0061] As described above, the control unit 210 renews the time
information recorded on the spray-time table considering the water
pressure.
[0062] When the water pressure is low, a predetermined time is
added to the time recorded on the spray-time table and the
spray-time table is renewed with the added time.
[0063] FIG. 5 is a flowchart illustrating a control method of the
washing machine according to an embodiment of the present
invention.
[0064] First, the control unit 210 detects the amount of the
laundry loaded in the washing tub 30 using the rotation of the
washing tub 30 or the pulsator 40. When the laundry is dry laundry
that is relatively light, the control unit 201 accelerates the
pulsator 40 in a direction at about 200 RPM, after which the
control unit 201 determines the amount of the laundry with
reference to a speed reduction time of the washing tub or a speed
reduction gradient. At this point, when the amount of the laundry
loaded in the washing tub 30 is relatively small, the speed of the
pulsator 40 is steeply reduced. On the other hand, when the amount
of the laundry loaded in the washing tub 30 is relatively large,
the speed of the pulsator 40 is slowly reduced.
[0065] If the laundry is wet laundry that is relatively heavy, the
control unit 210 accelerates the washing tub 30 instead of the
pulsator 40 at about 40-60 RPM, after which the control unit 210
determines the amount of the laundry with reference to a speed
reduction gradient attained when the washing tub puts on the brakes
with reserve power. (S301).
[0066] The control unit 210 may detect the amount of the laundry
using the wet or dry laundry. Alternatively, the control unit 210
may detect the amount of the laundry using firstly the dry laundry
and detect using secondly the wet laundry. When both of the method
for detecting the amount of the laundry using the dry laundry and
the method for detecting the amount of the laundry using the wet
laundry are used, the control unit 210 may determines a mean value
of the detected amount for the dry laundry and the detected amount
for the wet laundry as the amount of the laundry. Alternatively,
when the dry laundry is detected and it is determined that the
amount of the laundry is light, the detected amount for the dry
laundry may be determined as the amount of the laundry.
Alternatively, when the detected amount for the dry laundry
deviates a predetermined amount (e.g., about 6 kg), the detected
amount for the wet laundry may be determined as the amount of the
laundry (S302).
[0067] Next, the control unit 210 determines the water amount
section and spraying time that correspond to the amount of the
laundry with reference to the spray-time table stored in the memory
270. At this point, the control unit 210 determines a reference
amount to be supplied to the washing tub 30. When the reference
amount is determined, the control unit 210 sprays the washing water
into the washing tub 30 through a spraying hole provided near the
cover 150 by controlling the water supply driving unit 250 (S303).
Next, the control 210 determines if the amount of the washing water
sprayed into the washing tub 30 reaches the reference amount
(S304), measures the time required for the amount of the washing
water reaches the reference amount (S305), and determines the water
pressure of the washing water with reference to the reference table
stored in the memory 270 (S306). After this, the control unit 210
increases and reduces the spraying time recorded on the spray-time
table with reference to the water pressure of the washing water and
sprays the washing water to the washing tub 30 for the increased or
reduced time.
[0068] Finally, the control unit 210 performs the remaining cycles
such as the wash, rinse, and spinning cycles when the washing water
sprayed toward the laundry evenly wets the laundry (S309)
[0069] FIG. 6 is a reference view illustrating an example of a
method of detecting a laundry load.
[0070] Referring to FIG. 6, in a laundry load table, gradient
values are listed in each of laundry load sections //3, //14, //5,
//6, and //7. The laundry load table is a table corresponding to a
gradient of rotational reduction section and a laundry load of dry
laundry or wet laundry and is provided in the form of a data table
in the memory 270.
[0071] In FIG. 6, the laundry load table is provided for the
respective laundry load sections //3, //4, //5, //6, and //7.
Gradient values (135, 129, 122 . . . , and the like) corresponding
to the respective laundry load sections are written on the laundry
load table. For example, if the speed reduction gradient value of
the motor 50 is about 183, it may be determined that the weight
corresponds to the laundry load section "//4."
[0072] Although not shown in the drawings, a weight value range of
the laundry may be assigned to each of the laundry load sections.
For example, a weight value range of about 3 Kg to about 4 Kg may
be assigned to the laundry load section //3.
[0073] FIG. 7 is a reference view illustrating an example of a
spraying unit formed between the cover and the case.
[0074] The washing machine of an embodiment of the present
invention sprays the washing water toward the laundry to evenly wet
the laundry. The washing machine uses a spraying unit provided in
the form of a nozzle having a narrow outlet to spray the washing
water.
[0075] The spraying unit 120 is a unit for spraying the circulation
water into the inner tub 31. The spraying unit 120. The spraying
unit 120 has a plurality of nozzle holes (not shown) that are
relatively small to spray the washing water into the inner tub 31
through a shower manner. Since the spraying unit 120 directly
sprays the washing water toward the laundry loaded in the inner tub
31, it can evenly effectively wet the laundry. This method has an
advantage of reducing an amount of the washing water that is
necessary to wet the laundry as compared with a typical method
where the washing water is supplied into the inner tub 31 up to a
predetermined water level so that the laundry can be sunk under the
washing water. Particularly, the spraying unit 120 may be set such
that a spraying direction thereof is set toward a sidewall of the
inner tub 31 to effectively wet the laundry adhered to the
sidewall.
[0076] FIG. 8 is s a reference view illustrating a method of
controlling the washing machine according to another embodiment of
the present invention.
[0077] Referring to FIG. 8, the control unit 210 loads and drives a
driving pattern for each of the wash courses stored in the memory
in accordance with a wash course set by a user. The control unit
210 determines if a treatment cycle of the washing machine is a
wash cycle with reference to the driving pattern of each of the
wash courses (S401). When the treatment cycle is the wash cycle,
the control unit 210 supplies the washing water to the washing tub
30 by controlling the water supply driving unit 250. At this point,
the control unit 210 determines the water pressure of the washing
water with reference to a time for which the washing water is
supplied to the washing tub 30 (S403). The determination of the
water pressure is realized with reference to a reference amount and
a reference table corresponding to the reference amount, which are
stored in the memory 270. After determining the water pressure of
the control unit 210, the control unit 210 stores the determined
water pressure in the memory 270 and performs the wash cycle for
the laundry (S404).
[0078] Next, the control unit 210 determines if it is time to
perform the rinse cycle for the laundry with reference to the
driving pattern stored in the memory (S405). When it is determined
that it is time to perform the rinse cycle for the laundry, the
control unit 210 determines the time for which the washing water
will be sprayed into the washing tub 30 with reference to water
pressure information stored in the memory 270 (S406) and sprays the
washing water into the washing tub 30 for the determined time
(S407).
[0079] However, the present invention is not limited to the above.
For example, when the water pressure is determined, the spraying
time is preset according to the determined water pressure and the
water pressure and spraying time are stored in the memory 270,
after which the water spraying is performed in accordance with the
spraying time that is stored in the spinning cycle.
[0080] Finally, the control unit 210 finishes all cycles with
respect to the laundry by spinning the washing tub 30 for the rinse
and spin cycles with respect to the laundry (S408).
[0081] While the present invention has been particularly shown and
described with reference to exemplary embodiments thereof, it will
be understood by those of ordinary skill in the art that various
changes in form and details may be made therein without departing
from the spirit and scope of the present invention as defined by
the following claims.
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