U.S. patent application number 16/830954 was filed with the patent office on 2020-10-01 for washing machine and control method thereof.
The applicant listed for this patent is Samsung Electronics Co., Ltd.. Invention is credited to Atsushi OHYAGI, Hiroki TAKITA.
Application Number | 20200308751 16/830954 |
Document ID | / |
Family ID | 1000004837748 |
Filed Date | 2020-10-01 |
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United States Patent
Application |
20200308751 |
Kind Code |
A1 |
OHYAGI; Atsushi ; et
al. |
October 1, 2020 |
WASHING MACHINE AND CONTROL METHOD THEREOF
Abstract
A washing machine includes a drum accommodating laundry, a motor
configured to rotate the drum, a speed sensor configured to detect
a rotational speed of the drum, and a processor. The processor
configured to: determine a mass of the laundry corresponding to
each of a first acceleration section and a second acceleration
section based on the rotational speed detected by the speed sensor,
and control the motor such that an absolute value of the rotational
speed at a start time of the first acceleration section is
substantially the same as an absolute value of a rotational speed
at a start time of the second acceleration section. A rotational
direction of the drum corresponding to the rotational speed at the
start time of the first acceleration section is opposite to a
rotational direction of the drum corresponding to the rotational
speed at the start time of the second acceleration section.
Inventors: |
OHYAGI; Atsushi;
(Yokohama-shi, JP) ; TAKITA; Hiroki;
(Yokohama-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electronics Co., Ltd. |
Suwon-si |
|
KR |
|
|
Family ID: |
1000004837748 |
Appl. No.: |
16/830954 |
Filed: |
March 26, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D06F 34/18 20200201;
D06F 37/34 20130101; D06F 2103/46 20200201; D06F 2103/04 20200201;
D06F 2103/24 20200201; D06F 37/304 20130101; D06F 2105/48 20200201;
D06F 21/02 20130101 |
International
Class: |
D06F 34/18 20060101
D06F034/18; D06F 37/34 20060101 D06F037/34; D06F 21/02 20060101
D06F021/02; D06F 37/30 20060101 D06F037/30 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 27, 2019 |
JP |
2019-061480 |
Mar 2, 2020 |
KR |
10-2020-0026081 |
Claims
1. A washing machine comprising a drum in which laundry is
accommodated; a motor configured to rotate the drum; a speed sensor
configured to detect a rotational speed of the drum; and a
processor configured to: identify a mass of the laundry
corresponding to each of a first acceleration section and a second
acceleration section based on the rotational speed detected by the
speed sensor, and control the motor such that an absolute value of
the rotational speed at a start time of the first acceleration
section is substantially the same as an absolute value of the
rotational speed at a start time of the second acceleration
section, wherein a rotational direction of the drum corresponding
to the rotational speed at the start time of the first acceleration
section is opposite to a rotational direction of the drum
corresponding to the rotational speed at the start time of the
second acceleration section.
2. The washing machine of claim 1, wherein: before the start time
of the first acceleration section, the processor is further
configured to control the motor to drive at substantially the same
rotational speed in a first constant speed section, and before the
start time of the second acceleration section, the processor is
further configured to control the motor to drive at substantially
the same rotational speed in the first constant speed section.
3. The washing machine of claim 1, wherein a position of the
laundry at the start time of the first acceleration section is
different by 180 degrees with respect to a center of the drum from
a position of the laundry at the start time of the second
acceleration section.
4. The washing machine of claim 3, wherein the processor is further
configured to control the drum to rotate an integer number of times
in the first and second acceleration sections.
5. The washing machine of claim 4, wherein the processor is further
configured to identify the mass of the laundry based on the mass
detected in each of the first acceleration section and the second
acceleration section.
6. The washing machine of claim 5, wherein the processor is further
configured to identify the mass of the laundry based on an average
of the mass detected in the first acceleration section and the
second acceleration section.
7. The washing machine of claim 1, wherein the processor is further
configured to identify the start time of the first acceleration
section and the start time of the second acceleration section based
on a rotation angle of the drum.
8. The washing machine of claim 7, wherein, based on a half of a
rotation of the motor, the processor is further configured to
identify a difference between the rotation angle at the start time
of the first acceleration section and the rotation angle at the
start time of the second acceleration section.
9. The washing machine of claim 1, wherein the processor is further
configured to identify the start time of the first acceleration
section and the start time of the second acceleration section based
on at least one of the rotational speed, a current flowing in the
motor, or a voltage applied to the motor.
10. The washing machine of claim 9, wherein a phase difference of
one of the rotational speed of the motor, the current flowing in
the motor, or the voltage applied to the motor corresponding to the
start time of the first acceleration section and the start time of
the second acceleration section is 180 degrees.
11. The washing machine of claim 1, wherein, in a continuous
driving of the drum, the processor is further configured to:
perform the first acceleration section and the second acceleration
section; and control the rotational speed of the motor to be
substantially 30 revolutions per minute (rpm) or more in the first
acceleration section and the second acceleration section.
12. The washing machine of claim 1, wherein the processor is
further configured to control the rotational speed of the motor to
be substantially 300 rpm or less at an end time of the first and
second acceleration sections.
13. The washing machine of claim 1, wherein an angle of a rotation
axis of the drum with respect to a horizontal direction is from 0
(zero) degree to 45 degrees.
14. A control method of a washing machine comprising: detecting a
rotational speed of a drum in which laundry is accommodated;
identifying a mass of the laundry corresponding to each of a first
acceleration section and a second acceleration section based on the
detected rotational speed; and rotating the drum such that an
absolute value of the rotational speed at a start time of the first
acceleration section is substantially the same as an absolute value
of the rotational speed at a start time of the second acceleration
section, wherein a rotational direction of the drum corresponding
to the rotational speed at the start time of the first acceleration
section is opposite to a rotational direction of the drum
corresponding to the rotational speed at the start time of the
second acceleration section.
15. The control method of claim 14, wherein the rotating further
comprises: rotating the drum at substantially the same rotational
speed in a first constant speed section before the start time of
the first acceleration section; and rotating the drum at
substantially the same rotational speed in the first constant speed
section before the start time of the second acceleration
section.
16. The control method of claim 14, wherein the rotating further
comprises rotating the drum such that a position of the laundry at
the start time of the first acceleration section is different by
180 degrees with respect to a center of the drum from a position of
the laundry at the start time of the second acceleration
section.
17. The control method of claim 16, wherein the rotating further
comprises rotating the drum an integer number of times in the first
and second acceleration sections.
18. The control method of claim 17, wherein the identifying of the
mass further comprises identifying the mass of the laundry based on
the mass detected in each of the first acceleration section and the
second acceleration section.
19. The control method of claim 18, wherein the identifying of the
mass further comprises identifying the mass of the laundry based on
an average of the mass detected in the first acceleration section
and the second acceleration section.
20. The control method of claim 14, wherein the rotating further
comprises identifying the start time of the first acceleration
section and the start time of the second acceleration section based
on a rotation angle of the drum.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims priority under 35
U.S.C. 119 to Korean Patent Application No. 10-2020-0026081, filed
on Mar. 2, 2020, in the Korean Intellectual Property Office, which
claims the benefit of Japanese Patent Application No. 2019-061480
filed on Mar. 27, 2019, in the Japan Patent Office, the disclosures
of which are herein incorporated by reference in their
entireties.
BACKGROUND
1. Field
[0002] The disclosure relates to a washing machine configured to
determine a mass of laundry.
2. Description of Related Art
[0003] Techniques for obtaining the mass of laundry in a washing
machine are known. When the mass of laundry is obtained, washing
time, quantity, etc. may be changed based on the obtained mass of
the laundry. For example, Patent Document 1 discloses a technique
that detects the mass of laundry based on rise time and fall time
of a rotational speed of a motor.
RELATED ART DOCUMENT
Patent Document
[0004] (Patent Document 1) JP2002126390 A
SUMMARY
[0005] Therefore, it is an aspect of the disclosure to provide a
washing machine capable of more accurately measuring a mass of
laundry even when an imbalance of laundry occurs.
[0006] Additional aspects of the disclosure will be set forth in
part in the description which follows and, in part, will be obvious
from the description, or may be learned by practice of the
disclosure.
[0007] In accordance with an aspect of the disclosure, a washing
machine includes a drum in which laundry is accommodated, a motor
configured to rotate the drum, a speed sensor configured to detect
a rotational speed of the drum, and at least one processor
configured to determine a mass of the laundry corresponding to each
of a first acceleration section and a second acceleration section
based on the rotational speed detected by the speed sensor, and
configured to control the motor wherein an absolute value of a
rotational speed at a start time of the first acceleration section
is substantially the same as an absolute value of a rotational
speed at a start time of the second acceleration section and a
direction of the rotational speed at, the start d me of the first
acceleration section is opposite to a direction of the rotational
speed at the start time of the second acceleration section.
[0008] Before the start time of the first acceleration section, the
at least one processor may allow the motor to drive at the
substantially the same rotational speed in a first constant speed
section, and before the start time of the second acceleration
section, the at least one processor may, allow the motor to drive
at the substantially the same rotational speed in the first
constant speed section.
[0009] A position of the laundry at the start time of the first
acceleration section may be different by 180 degrees from a
position of the laundry at the start time of the second
acceleration section with respect to a center of the drum.
[0010] The at least one processor may allow the drum to rotate an
integer number of times in the first and second acceleration
sections.
[0011] The at least one processor may determine the mass of the
laundry based on the mass detected in each of the first
acceleration section and the second acceleration section.
[0012] The at least one processor may determine the mass of the
laundry based on an average of the mass detected in the first
acceleration section and the second acceleration section.
[0013] The at least one processor may determine the start time of
the first acceleration section and the start time of the second
acceleration section based on a rotation angle of the drum.
[0014] Based on (n+0.5) rotation (n: natural number) of the motor,
the at least one processor may determine a difference between the
rotation angle at the start time of the first acceleration section
and the rotation angle at the start time of the second acceleration
section.
[0015] The at least one processor may determine the start time of
the first acceleration section and the start time of the second
acceleration section based on at least one of the rotational speed,
a current flowing in the motor, and a voltage applied to the
motor.
[0016] A phase difference of one of the rotational speed of the
motor, the current flowing in the motor, and the voltage applied to
the motor corresponding to the start time of the first acceleration
section and the start time of the second acceleration section may
be 180 degrees.
[0017] In a continuous driving of the drum, the at least one
processor may perform the first acceleration section and the second
acceleration section, and may allow the rotational speed of the
motor to be substantially 30 revolutions per minute (rpm) or more
between the first acceleration section and the second acceleration
section.
[0018] The at least one processor may allow the rotational speed of
the motor to be substantially 300 rpm or less at an end time of the
first and second acceleration sections.
[0019] An angle of a rotation axis of the drum with respect to a
horizontal direction may be from 0 (zero) degree to 45 degrees.
[0020] In accordance with another aspect of the disclosure, a
control method of a washing machine includes detecting a rotational
speed of a drum in which laundry is accommodated, determining a
mass of the laundry corresponding to each of a first acceleration
section and a second acceleration section based on the detected
rotational speed, and controlling the motor configured to the drum
wherein an absolute value of a rotational speed at a start time of
the first acceleration section is substantially the same as an
absolute value of a rotational speed at a start time of the second
acceleration section and a direction of the rotational speed at the
start time of the first acceleration section is opposite to a
direction of the rotational speed at the start time of the second
acceleration section.
[0021] The controlling may include allowing the motor to drive at
the substantially the same rotational speed in a first constant
speed section before the start time of the first acceleration
section, and allowing the motor to drive at the substantially the
same rotational speed in the first constant speed section before
the start time of the second acceleration section.
[0022] The controlling may include allowing a position of the
laundry at the start time of the first acceleration section to be
different by 180 degrees from a position of the laundry at the
start time of the second acceleration section with respect to a
center of the drum.
[0023] The controlling may include allowing the drum to rotate an
integer number of times in the first and second acceleration
sections.
[0024] The determining of the mass may include determining the mass
of the laundry based on the mass detected in each of the first
acceleration section and the second acceleration section.
[0025] The determining of the mass may include determining the mass
of the laundry based on an average of the mass detected in the
first acceleration section and the second acceleration section.
[0026] The controlling may include determining the start time of
the first acceleration section and the start time of the second
accelerationsection based on a rotation angle of the drum.
[0027] Before undertaking the DETAILED DESCRIPTION below, it may be
advantageous to set forth definitions of certain words and phrases
used throughout this patent document: the terms "include" and
"comprise," as well as derivatives thereof, mean inclusion without
limitation; the term "or," is inclusive, meaning and/or the phrases
"associated with" and "associated therewith," as well as
derivatives thereof, may mean to include, be included within,
interconnect with, contain, be contained within, connect to or
with, couple to or with, be communicable with, cooperate with,
interleave, juxtapose, be proximate to, be bound to or with, have,
have a property of, or the like; and the term "controller" means
any device, system or part thereof that controls at least one
operation, such a device may be implemented in hardware, firmware
or software, or some combination of at least two of the same. It
should be noted that the functionality associated with any
particular controller may be centralized or distributed, whether
locally or remotely.
[0028] Moreover, various functions described below can be
implemented or supported by one or more computer programs, each of
which is formed from computer readable program code and embodied in
a computer readable medium. The terms "application" and "program"
refer to one or more computer programs, software components, sets
of instructions, procedures, functions, objects, classes,
instances, related data, or a portion thereof adapted for
implementation in a suitable computer readable program code. The
phrase "computer readable program code" includes any type of
computer code, including source code, object code, and executable
code. The phrase "computer readable medium" includes any type of
medium capable of being accessed by a computer, such as read only
memory (ROM), random access memory (RAM), a hard disk drive, a
compact disc (CD), a digital video disc (DVD), or any other type of
memory. A "non-transitory" computer readable medium excludes wired,
wireless, optical, or other communication links that transport
transitory electrical or other signals. A non-transitory computer
readable medium includes media where data can be permanently stored
and media where data can be stored and later overwritten, such as a
rewritable optical disc or an erasable memory device.
[0029] Definitions for certain words and phrases are provided
throughout this patent document, those of ordinary skill in the art
should understand that in many, if not most instances, such
definitions apply to prior, as well as future uses of such defined
words and phrases.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] These and/or other aspects of the disclosure will become
apparent and more readily appreciated from the following
description of embodiments, taken in conjunction with the
accompanying drawings of which:
[0031] FIG. 1 is a view illustrating a structure of a washing
machine according to an embodiment of the disclosure;
[0032] FIG. 2 is a view illustrating a profile of intermittent
driving of a motor for obtaining a mass of laundry according to an
embodiment of the disclosure;
[0033] FIG. 3 is a view illustrating a profile of intermittent
driving of the motor for obtaining a mass of laundry according to
an embodiment of the disclosure;
[0034] FIG. 4 is a view illustrating an eccentric position due to
uneven distribution of the laundry in a drum according to an
embodiment of the disclosure; and
[0035] FIG. 5 illustrates a flow chart according to an embodiment
of the disclosure.
DETAILED DESCRIPTION
[0036] FIGS. 1 through 5, discussed below, and the various
embodiments used to describe the principles of the present
disclosure in this patent document are by way of illustration only
and should not be construed in any way to limit the scope of the
disclosure. Those skilled in the art will understand that the
principles of the present disclosure may be implemented in any
suitably arranged system or device.
[0037] In the following descriptions and drawings, corresponding
parts are represented by the same reference numerals. The sizes of
the elements shown in the drawings are not necessarily drawn to
scale.
[0038] FIG. 1 is a view illustrating a structure of a washing
machine 100 according to an embodiment of the disclosure. The
washing machine 100 includes a drum 110 in which laundry is
accommodated, a motor 120 configured to rotate the drum 110, a
controller 130 configured to control rotation of the motor 120, a
sensor 140 configured to detect a rotational speed of the drum 110,
and a processing portion 150.
[0039] Meanwhile, the controller 130 and the processing portion 150
may be implemented with at least one processor.
[0040] According to an embodiment, the sensor 140 detects a
rotation angle of the drum 110 in addition to the rotational speed
of the drum 110. The processing portion 150 may determine the mass
of the laundry based on the rotational speed in first and second
acceleration sections to be described later.
[0041] In various embodiments, the rotational speed of the drum 110
is used. The sensor 140 is a position sensor configured to directly
detect the rotational speed of the drum 110, but is not limited
thereto. Therefore, the sensor 140 may be any suitable sensor.
[0042] The processing portion 150 may typically include at least
one processor 152 and a memory 154. The processor 152 executes a
computer program configured to process of controlling the rotation
of the drum 110 and the motor 120 and configured to process of
obtaining the mass of the laundry. The memory 154 typically stores
such computer programs and associated data. The processor 152
outputs a signal for controlling the rotation of the motor 120 to
the controller 130. The controller 130 drives the motor 120 based
on the control signal from the processor 152. FIG. 1 illustrates
that the controller 130 and the processing portion 150 are separate
functional blocks, but may be implemented as a single functional
block.
[0043] FIG. 2 is a view illustrating a profile 200 of intermittent
driving of the motor 120 for obtaining a mass of laundry according
to an embodiment of the disclosure. In FIG. 2, a horizontal axis
represents the time, and a vertical axis represents the rotational
speed of the drum 110. The profile 200 includes a first constant
speed section 211, a first acceleration section 212, a stop section
215, a second constant speed section 221, and a second acceleration
section 222. A sign of the rotational speed indicates a rotational
direction of the drum 110. Therefore, from time 0 (zero) to the
stop section 215, the drum 110 rotates in one direction, and
thereafter rotates in the opposite direction.
[0044] According to an embodiment, the controller 130 controls the
rotation of the motor 120 to allow an absolute value of the
rotational speed of the drum 110 at the start of the first
acceleration section 212 to be the same as an absolute value of the
rotational speed of the drum 110 at the start of the second
acceleration section 222 and to allow sings thereof to be opposite
to each other.
[0045] FIG. 3 is a view illustrating a profile 300 of intermittent
driving of the motor 120 for obtaining a mass of laundry according
to an embodiment of the disclosure. In FIG. 3, a horizontal axis
represents the time, and a vertical axis represents the rotational
speed of the drum 110. The profile 300 includes a first constant
speed section 311, a first acceleration section 312, a second
constant speed section 321, and a second acceleration section 322.
Unlike the profile 200, the profile 300 does not include a stop
section.
[0046] According to an embodiment, the constant speed section, the
acceleration section, and the deceleration section may be provided
prior to the first constant speed section 311. Accordingly, a
position of the laundry in the drum 110 may be fixed in
advance.
[0047] According to an embodiment, the controller 130 controls the
rotation of the motor 120 to provide the first constant speed
section 311, in which the rotational speed of the drum 110 is
constant, prior to the first acceleration section 312 and to
provide the second constant speed section 321, in which the
rotational speed of the drum 110 is constant, prior to the second
acceleration section 322.
[0048] FIG. 4 is a view illustrating an eccentric position due to
uneven distribution of the laundry in the drum 110 according to an
embodiment of the disclosure. The drum 110 rotates about a rotation
axis 410. Laundry 420 in the drum 110 may have an uneven
distribution as illustrated in FIG. 4.
[0049] At this time, a center 430 of the drum 110 is also shifted
from the rotation axis 410 due to the uneven distribution of the
laundry 420. When it is assumed that a line, which is along the
rotation axis 410 and then intersects a plane corresponding to an
opening portion of the drum 110 perpendicular to the rotation axis
410, is a reference line 440, an angle of the center 430 with
respect to the reference line 440 corresponds to an eccentric
position 450 caused by the uneven distribution of the laundry 420
in the drum 110. The eccentric position 450 may be set in a range
of 0 to 360 degrees. In the disclosure, the position of the drum
110 is represented by the eccentric position 450, which may be
named as a phase.
[0050] According to an embodiment using the profile 200
(intermittent driving) or the profile 300 (continuous driving), a
start time of the first acceleration section and the second
acceleration section corresponds to two points in which the
eccentric position 450 caused by the uneven distribution of the
laundry 420 in the drum 110 is shafted by 180 degrees. In an
embodiment using the profile 300 (continuous driving), as shown in
FIG. 3, the eccentric position 450 at a start time of the first
acceleration section 312 is 270 degrees, and the eccentric position
450 at a start time of the second acceleration section 322 is 90
degrees. Therefore, the start time of the first acceleration
section 312 and the second acceleration section 322 corresponds to
the two points in which the eccentric position 450 caused by the
uneven distribution of the laundry 420 in the drum 110 is shafted
by 180 degrees. In another embodiment using the profile 200
(intermittent driving), a start time of the first acceleration
section 212 and the second acceleration section 222 corresponds to
two points in which the eccentric position 450 caused by the uneven
distribution of the laundry 420 in the drum 110 is shafted by 180
degrees.
[0051] In an embodiment using the profile 200 (intermittent
driving) or the profile 300 (continuous driving), the drum 110
rotates n times (n: natural number) in the first acceleration
section and the second acceleration section. For example, in an
embodiment, the drum 110 rotates once in the first acceleration
section 312 and the second acceleration section 322, but it is not
limited thereto. Therefore, as long as the number of rotation of
the drum 110 in the first acceleration section 312 is the same as
the number of rotation of the drum 110 in the second acceleration
section 322, the drum 110 may rotate n times (n: natural number)
other than once. "The number of rotation" of the drum represents
the number of times in which the drum rotates. For example, the
drum 110 may rotate two times in the first acceleration section 312
and the second acceleration section 322.
[0052] In an embodiment using the profile 200 (intermittent
driving) or the profile 300 (continuous driving), the processing
portion 150 obtains the mass based on the mass detected in the
first and second acceleration sections. When a torque of the motor
120 is constant, the acceleration in the first and second
acceleration sections depends on the mass of the laundry 420.
[0053] For example, when the mass of the laundry 420 is heavy, the
increase in the rotational speed of the drum 110 is small even when
the drum 110 accelerates in the acceleration section. However, when
the mass of the laundry 420 is light, the increase in the
rotational speed of the drum 110 increases based on the
acceleration of the drum 110 in the acceleration section.
Therefore, the processing portion 150 may obtain the mass of the
laundry 420 based on the increase amounts of the two rotational
speeds in the first and second acceleration sections.
[0054] In an embodiment using the profile 200 and the profile 300,
an angle of the rotation axis of the drum 110 of the washing
machine 100 according to the disclosure with respect to the
horizontal direction is from 0 (zero) degree to 45 degrees. In this
range, it is possible to effectively obtain the mass of the laundry
420 from two mass values based on the acceleration of the first
acceleration section 312 and the second acceleration section 322. A
washing machine operated in this range includes a washing machine
that is commonly referred as "a drum type washing machine". In the
drum type washing machine, the rotation axis of the drum 110 is
relatively close to the horizontal direction. Accordingly, due to
the gravity, the rotational speed may be reduced when the eccentric
position 450 moves up and the rotational speed may be increased
when the eccentric position 450 moves down. Even when such a
variation in the rotational speed occurs, it is possible to obtain
a value closer to the true mass of the laundry 420 based on the two
mass values of the laundry 420 obtained separately in the first
acceleration section and the second acceleration section, which
will be described later.
[0055] In the example of FIG. 3, because the start time of the
first acceleration section 312 and the second acceleration section
322 corresponds to the two points in which the eccentric position
450 caused by the uneven distribution of the laundry 420 in the
drum 110 is shafted by 180 degrees, it is possible to reduce an
error that may occur when detecting the mass of the laundry 420.
This effect is also obtained in the example of FIG. 2. It is
appropriate to determine the mass of the laundry 420 based on an
average of two masses detected in the first and second acceleration
sections. Accordingly, the processing portion may more reduce the
error that may occur when detecting the mass of the laundry
420.
[0056] By the continuous driving of the profile 300, it is possible
to detect the mass two times while maintaining the arrangement of
the laundry 420 in the drum 110 that is maintaining the eccentric
position and the imbalance.
[0057] The imbalance is a parameter determined by a weight
corresponding to the uneven distribution of the laundry 420 in the
drum 110 and a distance of the laundry 420 from the rotation axis
410. As the weight and the distance are increased, the imbalance
may be increased. When the rotation direction is changed as
illustrated in the profile 200, a stop section of the motor 120 is
generated. In the stop section, the centrifugal force is lost, and
the laundry 420 attached to the side of the drum 110 falls down in
the vertical direction and thus the arrangement of the laundry 420
may be changed.
[0058] At this time, the eccentric position and the unbalance
amount change. The eccentric position is corrected by monitoring
the phase of the rotational speed or the like, but the imbalance is
not corrected. Therefore, the profile 200 has a larger deviation
than the profile 300.
[0059] Accordingly, the profile 300 is more appropriate than the
profile 200.
[0060] In an embodiment using the profile 300, the first
acceleration section 312 and the second acceleration section 322
are generated during continuous driving of the drum, and the
rotational speed of the drum is maintained at 30 rpm or more in the
first acceleration section 312 and the second acceleration section
322.
[0061] "Rpm" may mean revolutions per minute of the motor and the
drum.
[0062] Accordingly, the movement of the laundry 420 in the drum 110
may be reduced between the first acceleration section 312 and the
second acceleration section 322.
[0063] As a result, the error at the detection of the mass of the
laundry 420 may be reduced.
[0064] As mentioned above, the start time of the first acceleration
section (for example 312) and the second acceleration section (for
example 322) corresponds to the two points in which the eccentric
position 450 caused by the uneven distribution of the laundry 420
in the drum 110 is shafted by 180 degrees. Therefore, it can be
detected that the phase of the eccentric position 450 is shifted by
180 degrees at the start time of the first acceleration section and
the second acceleration section.
[0065] According to an embodiment, the processing portion 150
obtains the two points, in which the phase is shifted by 180
degrees, based on the rotation angle of the drum 110.
[0066] The rotation angle of the drum 110 may be detected by the
sensor 140. More particularly, the difference between the rotation
angle of the two points, in which the phase is shifted by 180
degrees, corresponds to (n+0.5) rotation (n: natural number).
[0067] The phase detection of the start time based on the rotation
angle may be performed in such a way that an angle at the start
time of the first acceleration section is stored and then the
second acceleration section starts at a timing in which the
rotation angel is shafted by 180 degrees from the stored angle.
[0068] The phase detection of the start time based on the rotation
angle is more accurately performed in the embodiment using the
profile 300 (continuous driving).
[0069] According to an embodiment, the processing portion 150
obtains the two points, in which the phase is shifted by 180
degrees, based on at least one of the rotational speed of the drum
110, a current flowing in the motor 120, and a voltage applied to
the motor 120. More particularly, in the two points in which the
phase is shifted by 180 degrees, a phase difference of one of the
rotational speed of the drum 110, the current flowing in the motor
120, and the voltage applied to the motor 120 is 180 degrees.
[0070] Due to the influence of the eccentric position 450 caused by
the uneven distribution of the laundry 420 in the drum 110, the
rotational speed of the drum is changed even in the constant speed
section.
[0071] When the variation of the rotational speed is plotted with
respect to the time axis, a sine wave shape may be generated. There
is a correlation between the phase of the waveform and the
eccentric position 450. Therefore, the eccentric position 450 may
be obtained from the phase of the sine wave waveform indicating the
variation of the rotational speed. As the uneven distribution of
the laundry 420 in the drum 110 is reduced, the amplitude of the
waveform is reduced and the phase detection is difficult.
[0072] However, when the uneven distribution is small, the uneven
distribution has little effect on the mass detection. Therefore,
even when the phase is not detected, there is little effect on the
difference (i.e., deviation) of the mass detected in the two
acceleration sections. By detecting the phase of the variation
waveform of the rotational speed, the controller may start the
second acceleration section at a timing that is shifted by 180
degrees from the start time of the first acceleration section.
[0073] In the same manner as the above mentioned variation of the
rotational speed of the drum, the current flowing in the motor 120
and the voltage applied to the motor 120 also vary in the constant
speed section. Therefore, by using any one of the current flowing
in the motor 120 or the voltage applied to the motor 120, it is
possible to detect the phase at the start time in the same manner.
For example, the current flowing in the motor 120 and the voltage
applied to the motor 120 may be detected by the controller 130.
[0074] As mentioned above, it is possible to obtain the mass of the
laundry 420 based on the acceleration of the first and second
acceleration sections. In an embodiment using the profile 200
(intermittent driving) and the profile 300 (continuous driving), it
is appropriate that the rotational speed of the drum 110 at an end
time of the first and second acceleration sections is 300 rpm or
less in terms of the load of the motor 120. In this range, it is
possible to effectively obtain the mass of the laundry 420 based on
the acceleration of the first and second acceleration sections.
[0075] FIG. 5 illustrates a flow chart according to an embodiment
of the disclosure.
[0076] Referring to FIG. 5, the sensor may detect the rotational
speed of the drum (1001).
[0077] Meanwhile, the processor may control the drum by controlling
the motor, and the drum may be driven in the first acceleration
section (1002).
[0078] The processor may determine the mass of laundry
corresponding to the first acceleration section (1003).
[0079] The processor may perform the second acceleration section by
controlling the motor at a point shifted by 180 degrees from the
phase of the laundry at the start time of the first acceleration
section (1004).
[0080] The processor may determine the mass of the laundry
corresponding to the second acceleration section (1005).
[0081] The processor may determine the final mass of the laundry
based on an average of the mass of the laundry obtained in the
first acceleration section and the mass of the laundry obtained in
the second acceleration section (1006).
[0082] As is apparent from the above description, the washing
machine may more accurately measure the mass of laundry even when
an imbalance of laundry occurs.
[0083] Each of the various functions in the disclosure may be
realized by a single element or may be realized by a plurality of
elements. Conversely, multiple functions may be realized by a
single element. Each function may be realized by hardware,
software, or a combination of hardware and software. The flowchart
in the disclosure includes a plurality of blocks. The processing of
these blocks may be performed serially or in parallel. Also, the
order of some blocks may be changed.
[0084] The apparatus and the subject of the method of the
disclosure include a computer. When the computer executes the
program, the main functions of the apparatus and the subject of
method of the disclosure are realized. The computer has a processor
operating according to the program as the main hardware
configuration. The processor may be any type as long as the
function can be realized by executing a program. The processor is
composed of one or more electronic circuits including semiconductor
integrated circuits (IC) or large scale integration (LSI). The
plurality of electronic circuits may be integrated in one chip or
may be provided in a plurality of chips. The plurality of chips may
be integrated into one device or may be provided in the plurality
of devices.
[0085] Although a few embodiments of the disclosure have been shown
and described, it would be appreciated by those skilled in the art
that changes may be made in these embodiments without departing
from the principles and spirit of the disclosure, the scope of
which is defined in the claims and their equivalents.
DESCRIPTION OF SYMBOLS
[0086] 100: washing machine [0087] 110: drum [0088] 120: motor
[0089] 130: controller [0090] 140: sensor [0091] 150: processing
portion [0092] 152: processor [0093] 154: memory
[0094] Although the present disclosure has been described with
various embodiments, various changes and modifications may be
suggested to one skilled in the art. It is intended that the
present disclosure encompass such changes and modifications as fall
within the scope of the appended claims.
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