U.S. patent application number 15/009653 was filed with the patent office on 2016-08-04 for clothing dryer and method of controlling the same.
The applicant listed for this patent is Samsung Electronics Co., Ltd. Invention is credited to Geun Kang, Hyung-Woo Lee, Hye Joon Seok, Sang Oh Yoo.
Application Number | 20160222576 15/009653 |
Document ID | / |
Family ID | 56552902 |
Filed Date | 2016-08-04 |
United States Patent
Application |
20160222576 |
Kind Code |
A1 |
Yoo; Sang Oh ; et
al. |
August 4, 2016 |
CLOTHING DRYER AND METHOD OF CONTROLLING THE SAME
Abstract
Disclosed herein is a dryer which includes a drum for
accommodating an object to be dried, a combustion device for
combusting gas to heat air, a blowing device for transferring the
heated air into the drum, and a valve assembly for controlling a
gas discharge amount supplied to the combustion device, wherein the
valve assembly may operate in one mode among a high heating power
mode which maximizes the gas discharge amount, a low heating power
mode which generates 50% or less heating power compared to the high
heating power mode, and a standby mode which blocks the gas
discharge.
Inventors: |
Yoo; Sang Oh; (Hwaseong-si,
KR) ; Lee; Hyung-Woo; (Suwon-si, KR) ; Seok;
Hye Joon; (Yeoju-si, KR) ; Kang; Geun;
(Hwaseong-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electronics Co., Ltd |
Suwon-si |
|
KR |
|
|
Family ID: |
56552902 |
Appl. No.: |
15/009653 |
Filed: |
January 28, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D06F 2103/08 20200201;
D06F 2105/28 20200201; D06F 58/38 20200201; D06F 58/263 20130101;
D06F 58/30 20200201; D06F 58/50 20200201 |
International
Class: |
D06F 58/28 20060101
D06F058/28 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 30, 2015 |
KR |
10-2015-0014737 |
Claims
1. A clothing dryer comprising: a drum configured to accommodate an
object to be dried; a combustion device configured to combust gas
to heat air; a blowing device configured to transfer the heated air
into the drum; and a valve assembly configured to control a gas
discharge amount supplied to the combustion device, wherein the
valve assembly is configured to operate in one mode among a high
heating power mode that maximizes the gas discharge amount, a low
heating power mode that generates 50% or less heating power
compared to the high heating power mode, and a standby mode that
blocks the gas discharge.
2. The clothing dryer according to claim 1, wherein the valve
assembly further comprises an output control valve configured to
close a gas flow passage to decrease an open rate.
3. The clothing dryer according to claim 1, further comprising: a
dryness sensor configured to detect a dryness level of an object to
be dried; and a controller configured to compare the dryness level
detected from the dryness sensor to a reference dryness level in
order to control the valve assembly such that the operation mode of
the valve assembly is changed.
4. The clothing dryer according to claim 1, wherein the low heating
power mode is configured to generate 30% heating power compared to
the high heating power mode.
5. The clothing dryer according to claim 1, further comprising: a
temperature sensor configured to measure a temperature of air that
flows into the drum; and a controller configured to compare the
temperature measured from the temperature sensor to a reference
temperature in order to control the valve assembly such that the
operation mode of the valve assembly is changed.
6. The clothing dryer according to claim 3, wherein the controller
is configured to control the valve assembly to operate alternately
between the high heating power mode and the low heating power
mode.
7. The clothing dryer according to claim 5, wherein the controller
is configured to control the valve assembly to operate alternately
between the high heating power mode and the low heating power
mode.
8. The clothing dryer according to claim 1, wherein the clothing
dryer further comprises a dryness sensor configured to detect a
dryness level of an object to be dried, and determine a maintenance
time of the high heating power mode based on the dryness level
change rate detected from the dryness sensor.
9. The clothing dryer according to claim 1, wherein the combustion
device further comprises an igniter configured to ignite gas, and a
controller configured to control the valve assembly to operate in
the high heating power mode when the igniter operates.
10. The clothing dryer according to claim 9, wherein the valve
assembly further comprises a safety valve configured to determine
whether to discharge gas or not.
11. The clothing dryer according to claim 10, wherein the
controller is configured to control the safety valve to be open
when the temperature of the igniter reaches an ignition point of
the gas.
12. A clothing dryer comprising: a controller configured to control
an operation; a drum configured to accommodate an object to be
dried; a valve assembly configured to control heating power by
controlling a gas discharge amount; a combustion device configured
to combust the gas discharged from the valve assembly to generate
hot air; and a blowing device configured to transfer the hot air
into the drum, wherein the valve assembly further comprises an
output control valve configured to decrease an open rate of the
valve assembly to a predetermined open rate in order to control the
gas discharge amount.
13. The clothing dryer according to claim 12, wherein: the clothing
dryer further comprises a dryness level measurement device
configured to measure a dryness level of the object to be dried;
and the output control valve is configured to decrease the open
rate of the valve assembly to be low until the dryness level of the
object to be dried reaches a preset reference dryness level.
14. The clothing dryer according to claim 12, wherein the output
control valve is configured to decrease the open rate of the valve
assembly for a reference time in which a dryness level of the
object to be dried is preset.
15. The clothing dryer according to claim 12, wherein the valve
assembly further comprises a safety valve configured to determine
whether to discharge gas or not.
16. A method of controlling a clothing dryer that includes a
combustion device in which heating power is controlled by a valve
assembly that controls a gas discharge amount in accordance with a
plurality of predetermined open rates, the method comprising:
controlling the valve assembly to a low open rate among the
plurality of open rates to dry an object to be dried in a low
heating power mode; and when the dryness level of the object to be
dried reaches a preset reference dryness level, controlling the
valve assembly to a high open rate among the plurality of open
rates to dry an object to be dried in a high heating power
mode.
17. The method of claim 16, wherein controlling valve assembly
further comprises closing a gas flow passage to decrease an open
rate.
18. The method of claim 16, further comprising: detecting a dryness
level of the object to be dried; and comparing the dryness level
detected from the dryness sensor to a reference dryness level in
order to control the valve assembly such that an operation mode of
the valve assembly is changed.
19. The method of claim 16, wherein the low heating power mode
generates 30% heating power compared to the high heating power
mode.
20. The method of claim 16, further comprising: measuring a
temperature of air that flows into a drum; and comparing the
temperature measured from the temperature sensor to a reference
temperature in order to control the valve assembly such that the
operation mode of the valve assembly is changed.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S) AND CLAIM OF PRIORITY
[0001] The present application is related to and claims the benefit
of Korean Patent Application No. 10-2015-0014737, filed on Jan. 30,
2015 in the Korean Intellectual Property Office, the disclosure of
which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The present disclosure relates to a clothing dryer which
dries an object to be dried and a method of controlling the
same.
BACKGROUND
[0003] Generally, a clothing dryer is an apparatus which rotates a
drying drum, in which wet clothing is accommodated, at a low speed
and allows high-temperature air to pass through the drying drum and
flow in the drying drum in order to dry the clothing in the drying
drum. The dryer may be classified as an exhaust type dryer which
exhausts high-temperature, humid air that has passed through the
drying drum out of the dryer, and a condensation type dryer which
removes moisture from high-temperature, humid air that has passed
through the drying drum and circulates the air back into the drying
drum. Also, the dryer may be classified as an electric drier and a
gas type dryer according to a method of heating air, such as a
heating means. The electric dryer heats air using electrical
resistance heat, and the gas type dryer heats air using heat
generated by combustion of gas. However, the gas type dryer is
capable of controlling heating power. The dryer may be classified
as the electric drier and the gas type dryer according to the
method of heating air, such as a heating means. The electric dryer
heats air using electrical resistance heat, and the gas type dryer
heats air using heat generated by combustion of gas.
SUMMARY
[0004] To address the above-discussed deficiencies, it is a primary
object to provide, for use in a dryer capable of efficiently
controlling heating power and a method of controlling the same.
[0005] According to an aspect, a dryer includes a drum for
accommodating an object to be dried, a combustion device for
combusting gas to heat air, a blowing device for transferring the
heated air into the drum, and a valve assembly for controlling a
gas discharge amount supplied to the combustion device, wherein the
valve assembly may operate in one mode among a high heating power
mode which maximizes the gas discharge amount, a low heating power
mode which generates 50% or less heating power compared to the high
heating power mode, and a standby mode which blocks the gas
discharge. Here, the low heating power mode may generate 30%
heating power compared to the high heating power mode.
[0006] In addition, the valve assembly may further include an
output control valve for closing a gas flow passage to decrease an
open rate. In addition, the dryer may further include a dryness
sensor for detecting a dryness level of an object to be dried, and
a control unit for comparing the dryness level detected from the
dryness sensor to a reference dryness level in order to control the
valve assembly such that the operation mode of the valve assembly
is changed. Here, the control unit may control the valve assembly
to operate alternately between the high heating power mode and the
low heating power mode. In addition, the dryer may further include
a temperature sensor for measuring a temperature of air which flows
into the drum, and a control unit for comparing the temperature
measured from the temperature sensor to a reference temperature in
order to control the valve assembly such that the operation mode of
the valve assembly is changed. Here, the control unit may control
the valve assembly to operate alternately between the high heating
power mode and the low heating power mode.
[0007] The dryer may further include a dryness sensor for detecting
a dryness level of an object to be dried, and determine a
maintenance time of the high heating power mode based on the
dryness level change rate detected from the dryness sensor. In
addition, the combustion device may further include an igniter for
igniting gas, and a control unit for controlling the valve assembly
to operate in the high heating power mode when the igniter
operates. In addition, the valve assembly may further include a
safety valve for determining whether to discharge gas or not. In
addition, the control unit may control the safety valve to be
opened when the temperature of the igniter reaches an ignition
point of gas. According to another aspect, a clothing dryer
includes a control unit for controlling an operation, a drum for
accommodating an object to be dried, a valve assembly capable
controlling heating power by controlling a gas discharge amount, a
combustion device for combusting the gas discharged from the valve
assembly to generate hot air, and a blowing device for transferring
the hot air into the drum. Here, the valve assembly may further
include an output control valve for decreasing an open rate of the
valve assembly to a predetermined open rate in order to control the
gas discharge amount.
[0008] In addition, the clothing dryer may further include a
dryness level measurement unit for measuring a dryness level of the
object to be dried, and the output control valve may decrease the
open rate of the valve assembly to be low until the dryness level
of the object to be dried reaches a preset reference dryness level.
In addition, the output control valve may decrease the open rate of
the valve assembly for a reference time in which a dryness level of
the object to be dried is preset. In addition, the valve assembly
may further include a safety valve for determining whether to
discharge gas or not.
[0009] According to another aspect, a method of controlling a
clothing dryer which includes a combustion device in which heating
power is controlled by a valve assembly which controls a gas
discharge amount in accordance with a plurality of predetermined
open rates may include controlling the valve assembly to a low open
rate among the plurality of open rates to dry an object to be dried
in a low heating power mode and, when the dryness level of the
object to be dried reaches a preset reference dryness level,
controlling the valve assembly to a high open rate among the
plurality of open rates to dry an object to be dried in a high
heating power mode.
[0010] 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. 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
[0011] For a more complete understanding of the present disclosure
and its advantages, reference is now made to the following
description taken in conjunction with the accompanying drawings, in
which like reference numerals represent like parts:
[0012] FIG. 1 is a perspective view illustrating an exterior of a
clothing dryer according to an embodiment;
[0013] FIG. 2 is a schematic cross-sectional view of the clothing
dryer according to an embodiment;
[0014] FIG. 3 is a view schematically illustrating a front support
plate of the clothing dryer according to an embodiment;
[0015] FIG. 4 is a view illustrating in detail a guide member of
the clothing dryer according to an embodiment;
[0016] FIG. 5 is a view schematically illustrating a combustion
device of the clothing dryer according to an embodiment;
[0017] FIG. 6 is a view illustrating another embodiment of an
igniter of the clothing dryer according to an embodiment;
[0018] FIG. 7 is a view for describing a gas supply of a valve
assembly;
[0019] FIG. 8 is an exploded perspective view of the valve assembly
for describing an embodiment of an output control valve;
[0020] FIG. 9 is a control block diagram for describing in detail
an operation of the clothing dryer according to an embodiment;
[0021] FIG. 10 is a view illustrating a pulse generation frequency
of a dryness level detector in accordance with time according to an
embodiment;
[0022] FIG. 11 is a view for describing a combustion device
operation unit of the clothing dryer according to an
embodiment;
[0023] FIG. 12 is a view for describing an operation at the time of
ignition of the combustion device operation unit in FIG. 11;
[0024] FIG. 13 is a flow chart for describing an embodiment of a
method of controlling the clothing dryer according to an
embodiment;
[0025] FIG. 14 is a view for describing an air flow in a drying
process of the clothing dryer according to an embodiment;
[0026] FIG. 15 is a flow chart for describing an embodiment of an
ignition process in FIG. 10;
[0027] FIG. 16 is a view illustrating a temperature change in air
when exhaust blockage has occurred;
[0028] FIG. 17 is a view for describing an embodiment of a
re-ignition process;
[0029] FIG. 18 is a flow chart for describing in detail an
embodiment of a drying process in FIG. 13;
[0030] FIG. 19 is a graph illustrating a change in open rates in
the drying process of FIG. 18;
[0031] FIG. 20 is a flow chart for describing in detail another
embodiment of the drying process in FIG. 13;
[0032] FIG. 21 is a flow chart for describing in detail still
another embodiment of the drying process in FIG. 13;
[0033] FIG. 22 is a view for describing another embodiment of a
mode change in the drying process;
[0034] FIG. 23 is a view for describing a control for tracking a
temperature;
[0035] FIG. 24 is a view for describing a drying process which
limits an output based on the temperature;
[0036] FIG. 25 is a flow chart for describing an embodiment of
analyzing characteristics of an object to be dried; and
[0037] FIG. 26 is a view for describing a change in dryness level
in accordance with characteristics of an object to be dried.
DETAILED DESCRIPTION
[0038] FIGS. 1 through 26, 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 clothing dryer or other drying device.
Hereinafter, a clothing dryer and a method of controlling the same
will be described in detail with reference to the accompanying
drawings.
[0039] FIG. 1 is a perspective view illustrating an exterior of a
clothing dryer according to an embodiment, and FIG. 2 is a
schematic cross-sectional view of the clothing dryer according to
an embodiment. Referring to FIGS. 1 and 2, a clothing dryer 1
according to an embodiment may include a housing 10 forming the
exterior, a drum 20 rotatably installed within the housing 10, a
hot air supply unit 40 supplying hot air into the drum 20, a hot
air discharge unit 50 through which the air that has dried an
object to be dried in the drum 20 is discharged, a combustion
device 100 heating the air, and a circulation device circulating
the heated air to generate hot air.
[0040] The housing 10 forms the exterior of the clothing dryer 1. A
control panel 230 for controlling the clothing dryer 1 may be
provided at a top side of a front surface of the housing 10. Also,
an inlet 11 for inserting or withdrawing an object to be dried into
or from the drum 20 is formed at the front surface of the housing
10. In addition, a door 15 is coupled to the front surface of the
housing 10 by a hinge. The door 15 is provided in a shape
corresponding to the inlet 11. A user may open the door 15 by
rotating the door 15 forward, and insert or withdraw the object to
be dried into or from the drum 20. Also, the door 15 may be rotated
toward the clothing dryer 1 to close the drum 20.
[0041] In addition, a plurality of through-holes 17 may be provided
at the housing 10. Outside air may be introduced into the clothing
dryer 1 through the through-holes 17. As illustrated in FIG. 1, the
through-holes 17 may be provided at a lower portion of the front
surface and a side surface of the housing 10. Also, as illustrated
in FIG. 2, the through-holes 17 may be provided at a rear surface
of the housing 10. The drum 20 is rotatably installed within the
housing 10. The drum 20 may include a cylindrical portion 21, a
front support plate 22, and a rear support plate 23. The
cylindrical portion 21 is formed in a cylindrical shape with open
front and rear surfaces, the front support plate 22 is coupled to
the front surface of the cylindrical portion 21, and the rear
support plate 23 is coupled to the rear surface thereof.
[0042] Here, the inlet 11 for inserting or withdrawing the object
to be dried is formed at the front support plate 22, and a
plurality of lifts 24 may be provided inside the cylindrical
portion 21 along a circumferential direction. The object to be
dried inside the drum 20 is lifted and lowered repetitively by the
lifts 24. That is, the lifts 24 lift and lower the object to be
dried, thus allowing the object to be dried to be effectively
dried. In addition, rollers 30 for supporting the drum 20 are
provided at lower ends of an outer circumferential surface of the
drum 20. The rollers 30 may rotatably support the drum 20 by being
provided at front and rear lower ends, respectively, of the outer
circumferential surface of the drum 20. Here, the rollers 30 may be
fixed by the front support plate 22 and the rear support plate 23,
respectively.
[0043] The hot air supply unit 40 supplies high-temperature, dry
hot air to the drum 20. The hot air supplied to the drum 20 absorbs
moisture of the object to be dried inside the drum 20.
Specifically, the hot air supply unit 40 may include a combustion
chamber 41 in which air is heated by the combustion device 100, a
bottom duct 42 for guiding the heated air to a rear duct 43, the
rear duct 43 for guiding the heated air to a hot air outlet 45, and
the hot air outlet 45 through which the hot air is discharged into
the drum 20. Air in the combustion chamber 41 is heated by the
combustion device 100 to be described below. The combustion chamber
41 may be provided in a hollow conical shape in which a rear end
has a smaller diameter than a front end.
[0044] Air may be introduced through the front end of the
combustion chamber 41, and the air introduced through the front end
of the combustion chamber 41 is heated by the combustion device
100. A rear end of the combustion chamber 41 is coupled to the
bottom duct 42. The combustion chamber 41 may be coupled to the
bottom duct 42 by being inserted therein. For this, the diameter of
the bottom duct 42 may be provided to be larger than the diameter
of the rear end of the combustion chamber 41. In addition, due to
the difference between the diameter of the rear end of the
combustion chamber 41 and the diameter of the bottom duct 42, air
outside the combustion chamber 41 may be introduced into the bottom
duct 42.
[0045] The air heated in the combustion chamber 41 is guided to the
hot air outlet 45 through the bottom duct 42 and the rear duct 43.
The rear duct 43 is provided to be a predetermined distance apart
from the rear support plate 23, thus forming a rear flow passage 44
through which air may move. Meanwhile, a gas sensor 133 for
detecting a gas leak may be provided at one side of the combustion
chamber 41. The gas sensor 133 detects whether gas is leaked or
not. When a gas leak is detected, the clothing dryer 1 controls a
valve assembly (120 in FIG. 6) to prevent gas from being discharged
to a mixing tube (131 in FIG. 6). The gas sensor 133 may be
implemented using a catalytic combustion sensor, a semiconductor
sensor, a ceramic sensor etc., but is not limited thereto.
[0046] The hot air outlet 45 may be provided at an upper end of the
rear support plate 23. The heated air that has moved along the
bottom duct 42 and the rear duct 43 is introduced into the drum 20
through the hot air outlet 45, thus absorbing moisture of an object
to be dried inside the drum 20. A first temperature sensor 49 may
be provided at the rear duct 43. The first temperature sensor 49
detects a temperature of air guided into the drum 20 through the
rear flow passage 44. Here, the first temperature sensor 49 may be
implemented using a catalytic temperature sensor or a non-catalytic
temperature sensor. Specifically, the temperature sensor may be
implemented using at least one of a resistance temperature detector
(RTD) temperature sensor which uses a change in resistance of a
metal in accordance with a change in temperature, a thermistor
temperature sensor which uses a change in resistance of a
semiconductor in accordance with a change in temperature, a
thermocouple temperature sensor which uses an electromotive force
generated at both ends of a junction point of two types of metallic
lines formed of different materials, and an IC temperature sensor
which uses voltages at both ends of a transistor changing in
accordance with a temperature or current and voltage
characteristics of a P-N junction portion. However, the temperature
sensor is not limited thereto and may employ all possible means for
detecting a temperature.
[0047] In addition, although the first temperature sensor 49 is
illustrated in FIG. 2 as being provided at an upper portion of the
rear duct 43, the position of the first temperature sensor 49 is
not limited thereto. For example, the first temperature sensor 49
may be disposed at a lower portion of the rear duct 43, the bottom
duct 42, or the hot air outlet 45. The hot air discharge unit 50
guides the discharge of air in the drum 20. The high-temperature,
dry air introduced into the drum 20 through the hot air outlet 45
changes to a low-temperature, humid air as the air absorbs moisture
of the object to be dried. The low-temperature, humid air may be
discharged to the outside through the hot air discharge unit 50.
The hot air discharge unit 50 may be provided at a lower end of the
front support plate 22. FIG. 3 is a view schematically illustrating
a front support plate of the clothing dryer according to an
embodiment. FIG. 4 is a view illustrating in detail a guide member
of the clothing dryer according to an embodiment. Referring to
FIGS. 2 to 4, the hot air discharge unit 50 may include a guide
member 51 for guiding an introduction of air in the drum 20 into a
front flow passage 53, and a front duct 54 which forms the front
flow passage 53. The front flow passage 53 may be formed by the
front duct 54 provided at a lower portion of a front surface of the
clothing dryer 1.
[0048] The guide member 51 may be provided at a lower side of the
front support plate 22 to guide the introduction of the air in the
drum 20 into the front flow passage 53. A plurality of air inlets
52 may be provided at the guide member 51, and the air in the drum
20 may be guided to the front flow passage 53 through the plurality
of air inlets 52. A filter member 55 filters foreign substances
such as dust or lint included in the air introduced into the front
flow passage 53. A handle 56 which facilitates detachment of the
filter member 55 may be provided above the filter member 55.
[0049] A blowing device 60 circulates air in the clothing dryer 1.
The blowing device 60 includes a fan casing 61, a blowing fan 62
provided in the fan casing 61, and a driving motor 63 which rotates
the blowing fan 62. A front end of the fan casing 61 is connected
to the front flow passage 53, and a rear end of the fan casing is
connected to an exhaust duct 67. The driving motor 63 has a driving
shaft extending forward and connected to the blowing fan 62. Thus,
the blowing fan 62 may rotate by the driving motor 63. Also, the
driving shaft of the driving motor 63 may extend backward and be
connected to a pulley 64 for driving the drum 20. Since the pulley
64 and the drum 20 are connected by a belt 65, the drum 20 may
rotate by rotation of the driving motor 63. That is, the drum 20
and the blowing fan 62 may rotate at the same time by the driving
motor 63.
[0050] The blowing fan 62 rotates inside the fan casing 61 to
generate an air flow inside the clothing dryer 1. The air in the
front flow passage 53 is discharged out of the clothing dryer 1
through the exhaust duct 67 by the rotation of the blowing fan 62.
When the air in the front flow passage 53 is discharged through the
exhaust duct 67, the pressure in the front flow passage 53
decreases, and air in the drum 20 moves into the front flow passage
53. Also, the introduction of air heated by the combustion device
100 increases when the pressure of the air in the drum 20
decreases. That is, a supply of heated air from the hot air supply
unit 40 is facilitated when the blowing fan 62 rotates.
[0051] Meanwhile, a sensor mounting unit 58 on which a dryness
level detection unit 210 is mounted may be provided at the guide
member 51. Here, the dryness level detection unit 210 is an element
that generates an electrical signal in accordance with the amount
of moisture contained in an object to be dried. The dryness level
detection unit 210 will be described in detail herein.
[0052] A second temperature sensor 59 may be provided at the front
duct 54. The second temperature sensor 59 detects a temperature of
air guided to the front duct 54. Here, the second temperature
sensor 59 may be implemented using a catalytic temperature sensor
or a non-catalytic temperature sensor. In addition, although the
second temperature sensor 59 is illustrated in FIG. 2 as being
provided at the front duct 54, the position of the second
temperature sensor 59 is not limited thereto. For example, the
second temperature sensor 59 may be provided at one surface of an
inside of the guide member 51.
[0053] The combustion device 100 heats air to generate hot air.
Here, a heating power of the combustion device 100 may be
controlled to control the temperature of the hot air. The heating
power increases when a great amount of gas is combusted, and the
temperature of the hot air increases when the heating power
increases. The heating power decreases when a small amount of gas
is combusted, and the temperature of the hot air decreases when the
heating power decreases. The heating power of the combustion device
100 may be controlled in multiple stages. For example, the
combustion device 100 may be controlled to be one operation mode
among a high heating power mode, a low heating power mode, and a
standby mode. The high heating power mode refers to a state in
which the gas discharge amount is the maximum, and is a mode having
the highest heating power. The low heating power mode refers to a
state in which a smaller amount of gas is discharged compared to
the gas discharge amount in the high heating power mode, and is a
mode having a heating power lower than that in the high heating
power mode, such as 50% or less heating power compared to that in
the high heating power mode. The standby mode refers to a state in
which the gas discharge is blocked and gas is not combusted in the
combustion device 100.
[0054] Since the mode of the combustion device 100 changes in
accordance with the amount of gas discharged to the combustion
device 100, the mode of the combustion device 100 may be determined
by the valve assembly 120 which controls the amount of gas
discharged to the combustion device 100. Hereinafter, each
configuration of the combustion device 100 will be described in
detail.
[0055] FIG. 5 is a view schematically illustrating a combustion
device of the clothing dryer according to an embodiment. FIG. 6 is
a view illustrating another embodiment of an igniter of a
combustion device 100a of the clothing dryer according to an
embodiment. FIG. 7 is a view for describing a gas supply of a valve
assembly. FIG. 8 is an exploded perspective view of the valve
assembly 120 for describing an embodiment of an output control
valve. Referring to FIGS. 5 to 8, the combustion device 100 may
include a valve support 110, the valve assembly 120 for discharging
gas, and a combustion unit 130 for combusting gas. The valve
support 110 is coupled to the valve assembly 120 to support the
valve assembly 120. The valve support 110 includes a first support
111 extending from one end of the valve support 110 to support the
valve assembly 120, and a second support 115 extending from the one
end of the valve support 110 to support the other end of the valve
assembly 120.
[0056] The first support 111 and the second support 115 may
respectively include inclined surfaces 112 and 116 extending from
one end of the valve support 110 and vertically bent to be parallel
to a gas injection direction. The second support 115 extends in a
shorter length compared to the first support 111, and the inclined
surface 116 of the second support 115 is positioned at a lower side
than the inclined surface 112 of the first support 111. The valve
support 110 and the valve assembly 120 may be coupled by screws.
For the screw coupling, screw fastening holes 113 and 117 may be
formed at the inclined surface 112 of the first support 111 and the
inclined surface 116 of the second support 115, and screw fastening
holes may also be formed at the valve assembly 120 at positions
corresponding to the screw fastening holes 113 and 117 of the valve
support 110.
[0057] The valve assembly 120 may control the discharge amount of
gas to control the heating power of the combustion device 100. The
valve assembly 120 may control the gas discharge amount in multiple
stages in accordance with the operation modes. Specifically, the
valve assembly 120 may maximize the gas discharge amount in the
high heating power mode, decrease the gas discharge amount such
that the heating power is 50% or less compared to the high heating
power mode in the low heating power mode, and block the gas
discharge in the standby mode. The gas discharge amount of the
valve assembly 120 in accordance with the operation modes is
controlled in accordance with the open rate of the valve assembly
120. The open rate is an index which shows an extent to which the
valve is open. For example, the open rate is 100% when the valve is
completely open, and the open rate is 0% when the valve is
closed.
[0058] That is, the gas discharge amount increases and the heating
power increases as the open rate of the valve assembly 120 is
higher, and the gas discharge amount decreases and the heating
power decreases as the open rate of the valve assembly 120 is
lower. The open rate of the valve assembly 120 may be set as one of
a plurality of predetermined open rates. For example, the open rate
of the valve assembly 120 may be set as one of 100%, 30%, and 0%.
When the valve assembly 120 has the above open rates, the open rate
may be 100% in the high heating power mode, 30% in the low heating
power mode, and 0% in the standby mode. Specifically, the valve
assembly 120 may include a decompressor 122, a plurality of safety
valves 123 and 124, and an output control valve 125.
[0059] The valve assembly 120 receives gas through a gas inlet 121.
The gas inlet 121 is connected to a gas tube 140 to which gas is
guided from a gas supply source outside the housing 10. The
decompressor 122 controls the pressure of the gas introduced
through the gas inlet 121. Since the pressure of the gas introduced
through the gas inlet 121 is high, the pressure of the gas needs to
be lowered to a pressure suitable for combustion. The decompressor
122 decreases the pressure of the gas supplied through the gas
inlet 121. The gas, whose pressure is lowered by the decompressor
122, is applied to the output control valve 125. The plurality of
safety valves 123 and 124 may control whether the gas is discharged
or not. That is, the gas is discharged only when both of a first
safety valve 123 and a second safety valve 124 are open. The
combustion device 100 with the plurality of safety valves 123 and
124 is provided, such that an accident due to a gas leak may be
prevented.
[0060] The output control valve 125 may be provided between the
first safety valve 123 and the decompressor 122. The output control
valve 125 may control the open rate of the valve assembly 120. That
is, the output control valve 125 may control the heating power of
the combustion device 100. Since the gas discharge amount of the
valve assembly 120 is controlled in accordance with the open rate,
and the heating power is controlled in accordance with the gas
discharge amount as mentioned above, the output control device may
control the open rate of the valve to control the heating power of
the combustion device 100. The output control valve 125 may be
implemented using a solenoid valve. Hereinafter, an embodiment of
the output control valve 125 will be described in detail with
reference to FIG. 8. The output control valve 125 is formed of an
orifice 125b and a valve body 125a. A coil is provided in the valve
body 125a. A magnetic field is formed when current flows through
the coil in the valve body 125a, and the orifice 125b may move by
the magnetic field.
[0061] The orifice 125b may move back and forth along an axis
parallel to a gas flow passage 129. Specifically, the orifice 125b
moves forward toward the gas flow passage 129 when the magnetic
field is formed in the valve body 125a, and the orifice 125b moves
backward toward the valve body 125a when the magnetic field is not
formed in the valve body 125a. When the orifice 125b is positioned
in the valve body 125a, the gas flow passage 129 is completely open
and has a high first open rate (such as 100%). However, when the
orifice 125b moves forward toward the gas flow passage 129, the gas
flow passage 129 is closed by the orifice 125b. In addition, gas
moves along an inner flow passage 125c in the orifice 125b. That
is, the gas flow passage 129 is closed by the orifice 125b, causing
the open rate of the gas flow passage 129 to be lowered to a second
open rate (such as 30%). When the open rate is lowered from the
first open rate to the second open rate by the orifice 125b, the
amount of gas discharged to the combustion unit 130 reduces, such
that the heating power of the combustion device 100 decreases.
[0062] In other words, the output control valve 125 decreases the
open rate of the gas flow passage 129 to a predetermined second
open rate. Here, the predetermined second open rate may be
determined according to the size and structure of the orifice 125b.
For example, the second open rate may be determined according to
the size of the inner flow passage 125c formed in the orifice 125b.
The clothing dryer 1 may control the output control valve 125 to
control the heating power mode. Specifically, the clothing dryer 1
may control back and forth motions of the orifice 125b of the
output control valve 125 to control the operation mode. In other
words, since the gas flow passage 129 is completely open when the
orifice 125b moves forward, the gas discharge amount of the
combustion device 100 becomes the maximum, and the combustion
device 100 operates in the high heating power mode.
[0063] Since the gas flow passage 129 is partially closed when the
orifice 125b moves backward, the gas discharge amount of the
combustion device 100 decreases, and the combustion device 100
operates in the low heating power mode. As described herein, since
the heating power may be controlled by controlling the back and
forth motions of the orifice 125b, the combustion device 100 may
control the heating power without repeating extinction and
ignition. Meanwhile, when all of the safety valves are open, the
gas may be discharged through a gas outlet 126. Here, a front end
portion of the mixing tube 131 may be positioned in the combustion
chamber 41. The gas discharged through the gas outlet 126 is mixed
with air in the mixing tube 131. An igniter 132 may be provided at
the front end portion of the mixing tube 131. The igniter 132
ignites the gas mixed with air. The ignited gas heats surrounding
air while being continuously combusted with air.
[0064] The igniter 132 applies a temperature higher than the
ignition point of gas to ignite the gas mixed with air. The igniter
132 may be a heated type igniter 132 which is heated up to a
temperature greater than the ignition point of the gas as
illustrated in FIG. 5, but is not limited thereto. For example, the
igniter 132 may be implemented using an ignition plug 132a which
generates and ignites electric flames as illustrated in FIG. 6. The
operation of the clothing dryer 1 is described in detail
herein.
[0065] FIG. 9 is a control block diagram for describing in detail
an operation of the clothing dryer according to an embodiment.
Referring to FIG. 9, the clothing dryer 1 may include the dryness
level detection unit 210 for detecting the dryness level of an
object to be dried, a state detection unit 220 for detecting a
state of the clothing dryer 1, the control panel 230 for receiving
a control command from a user and providing information to the
user, a storage unit 240 for storing data to operate the clothing
dryer 1, and a control unit 270 for controlling the overall
operation of the clothing dryer 1. The dryness level detection unit
210 may detect the dryness level of an object to be dried. The
dryness level detection unit 210 may be installed in the drum 20
and come in contact with the object to be dried which rotates in
the drum 20 in order to detect the dryness level of the object to
be dried. Here, the dryness level is an index which shows an extent
to which the moisture included in the object to be dried is dried.
A higher dryness level signifies that a greater amount of moisture
is included in the object to be dried, and a lower dryness level
signifies that a lesser amount of moisture is included in the
object to be dried. Hereinafter, an embodiment of the dryness level
detection unit 210 will be described with reference to FIGS. 3 and
4.
[0066] Referring to FIGS. 3 and 4, the dryness level detection unit
210 may include a first electrode 211 and a second electrode 212.
The first electrode 211 and the second electrode 212 may be
provided at the guide member 51. The first electrode 211 and the
second electrode 212 are mounted on the sensor mounting unit 58
provided at the guide member 51. The first electrode 211 and the
second electrode 212 may be provided to be curved in accordance
with the shape of the sensor mounting unit 58. The first electrode
211 and the second electrode 212 may be mounted on the sensor
mounting unit 58 formed at the guide member 51 while being spaced
apart from each other. Since the first electrode 211 and the second
electrode 212 are provided to be a predetermined distance apart
from each other, the first electrode 211 and the second electrode
212 remain electrically open to each other.
[0067] When an object to be dried which has moisture comes in
contact with the first electrode 211 and the second electrode 212
at the same time, the first electrode 211 and the second electrode
212 are shorted by the moisture included in the object to be dried,
causing current to flow between the first electrode 211 and the
second electrode 212. That is, a current pulse is generated at the
first electrode 211 and the second electrode 212 by the object to
be dried which has moisture. Thus, the dryness level detection unit
210 may detect the dryness level of the object to be dried based on
the current pulse generated by the moisture of the object to be
dried. FIG. 10 is a view illustrating a pulse generation frequency
in accordance with time of a dryness level detector according to an
embodiment.
[0068] When the clothing dryer 1 operates, the frequency of the
current pulse generated at the first electrode 211 and the second
electrode 212 may change as illustrated in FIG. 10. The object to
be dried has high dryness level at an early stage of drying. Thus,
the current pulse is frequently generated by the object to be dried
when the drum 20 begins rotating, and the frequency of the current
pulse generation is also high as illustrated in FIG. 10. Meanwhile,
humidity of the object to be dried gradually decreases as the
object to be dried is dried by the hot air. Thus, as the object to
be dried is dried, the frequency of the current pulse generation
gradually decreases as illustrated in FIG. 10.
[0069] In other words, the dryness level detection unit 210 may
detect a change in the dryness level of the object to be dried
based on the frequency of the current pulse generation. Since the
moisture content in the object to be dried is high when the dryness
level is low, a current flow frequently occurs between the first
electrode 211 and the second electrode 212, such that the frequency
of the current pulse generation is high. Since the frequency of the
current flow generation between the first electrode 211 and the
second electrode 212 decreases when the object to be dried is dried
and the dryness level thereof is lowered, the frequency of the
current pulse generation decreases. Although the first electrode
211 and the second electrode 212 of the dryness level detection
unit 210 have been described as being provided at the guide member
51, the position of the dryness level detection unit 210 is not
limited thereto.
[0070] In addition, although the first electrode 211 and the second
electrode 212 are illustrated as having curved shapes in FIGS. 3
and 4, the shapes of the first electrode 211 and the second
electrode 212 are not limited thereto. For example, the first
electrode 211 and the second electrode 212 may be formed in the
shape of a rod. The state detection unit 220 may detect the state
of the clothing dryer 1. Here, the state of the clothing dryer 1
refers to various types of information such as a temperature of air
in the clothing dryer 1 and a gas ignition state to operate the
clothing dryer 1. The state detection unit 220 may include a
temperature sensor for detecting the temperature of air, the gas
sensor 133 for detecting a gas leak, etc. Specifically, the state
detection unit 220 may detect the temperature of air introduced
into the drum 20 using the first temperature sensor 49 and detect
the temperature of air discharged from the drum 20 using the second
temperature sensor 59.
[0071] In addition, the state detection unit 220 may detect whether
gas is leaked or not based on the gas sensor 133. For example, the
gas sensor 133 may be provided in the combustion chamber 41 as a
catalytic combustion sensor as illustrated in FIG. 2 to detect the
temperature in the combustion chamber 41. When the temperature in
the combustion chamber 41 detected by the catalytic combustion
sensor is lower than a preset temperature even though gas is being
discharged to the combustion chamber 41, the state detection unit
220 may detect that gas is leaking. The control panel 230 may
receive a control command from a user or provide information
related to the operation of the clothing dryer 1 to the user. The
control panel 230 may be provided at an upper side of the front
surface of the clothing dryer 1 as illustrated in FIG. 1 to be
easily manipulated by the user.
[0072] Specifically, the control panel 230 may include an input
unit 231 which receives a control command from the user. The user
may select one drying course among a plurality of preset drying
courses through the input unit 231. The drying courses may be
classified in accordance with the type, weight, etc., of the object
to be dried. Also, the drying courses may be classified in
accordance with energy efficiency or a target dryness level. Here,
the target dryness level refers to the final dryness level of the
object to be dried after drying is ended. The moisture content
included in the object to be dried that has reached the target
dryness level is low.
[0073] The input unit 231 may be implemented using devices such as
a touch sensor, a push button, a membrane button, a dial, and a
slider switch. Here, the touch sensor is a device which detects a
touch input of a user, and an electrostatic capacitive technology,
a resistance type technology, an infrared ray technology, and a
surface acoustic wave technology may be used for the touch sensor,
but the technologies are not limited thereto. In addition, the
control panel 230 may include a display unit 232 for displaying
information to the user. The display unit 232 may display a state
of the clothing dryer 1 or a time remaining until drying is
finished. The display unit 232 may be implemented using display
means such as a plasma display panel, a liquid crystal display
panel, a light-emitting diode panel, an organic light-emitting
diode panel, or an active organic light-emitting diode panel, but
is not limited thereto.
[0074] The storage unit 240 stores various types of data for the
operation of the clothing dryer 1. For example, the storage unit
240 may store firmware or various types of applications for the
operation of the clothing dryer 1. In addition, a drying algorithm
may be stored in the storage unit 240. The drying algorithm is
related to a procedure for drying an object to be dried. A proper
drying procedure differs in accordance with characteristics of the
object to be dried such as a material of the object to be dried or
the amount of object to be dried. Drying algorithms may be
different for each of the drying courses mentioned above. The
storage unit 240 may include a high-speed random access memory
(RAM), a magnetic disk, a static RAM (S-RAM), a dynamic RAM
(D-RAM), a read-only memory (ROM), etc., but is not limited
thereto.
[0075] A blowing device operation unit 250 may operate the blowing
device 60 in accordance with a control signal of the control unit
270. Specifically, the blowing device operation unit 250 may rotate
the driving motor 63 in accordance with the control signal of the
control unit 270 to rotate the blowing fan 62 and the drum 20.
Here, a rotation speed and a rotation direction of the driving
motor 63 may be controlled by the blowing device operation unit
250. When the driving motor 63 rotates by the blowing device
operation unit 250, the blowing fan 62 rotates such that humid air
in the drum 20 is discharged through an air inlet, and dry, hot air
is introduced into the drum 20 through the hot air outlet 45 due to
the pressure difference. Also, when the drum 20 rotates in
accordance with the rotation of the driving motor 63, the object to
be dried in the drum 20 is dried by the dry, hot air while being
lifted and lowered repetitively.
[0076] A combustion device operation unit 260 may operate the
combustion device 100 in accordance with the control signal of the
control unit 270. Hereinafter, an embodiment of the combustion
device operation unit 260 will be described in detail. FIG. 11 is a
view for describing a combustion device operation unit of the
clothing dryer according to an embodiment. FIG. 12 is a view for
describing an operation at the time of ignition of the combustion
device operation unit in FIG. 11. Referring to FIGS. 11 and 12, the
combustion device operation unit 260 may include a plurality of
switches 271 and 276, a plurality of coils 272, 273, and 274, and a
variable resistor 275. A first switch 271 may be in an off-state
and a second switch 276 provided at the igniter 132 may remain in
an on-state at an initial state. Here, the first switch 271 may be
turned on or off in accordance with the control signal of the
control unit 270, and the second switch 276 may be turned on or off
in accordance with the temperature of the igniter 132.
[0077] When the first switch 271 is converted to an on-state in
accordance with an ignition control signal of the control unit 270,
voltage is applied to a first valve coil 272, a booster coil 273,
and the variable resistor 275. When voltage is applied to the first
valve coil 272, the first safety valve 123 is opened by a magnetic
field generated at the first valve coil 272. Also, when voltage is
applied to the variable resistor 275, the igniter 132 is heated by
resistive heat. Here, the resistance value of the variable resistor
275 may be controlled. When the igniter 132 is heated by the
variable resistor 275 and the igniter 132 reaches a preset ignition
temperature, the second switch 276 is converted to an off-state as
illustrated in FIG. 12. Here, the ignition temperature is set as a
temperature higher than the ignition point of gas.
[0078] When the igniter 132 reaches the ignition temperature and
the second switch 276 is converted to the off-state, voltage is
applied to a second valve coil 274. When voltage is applied to the
second valve coil 274, a magnetic field is generated at the second
valve coil 274. The second safety valve 124 is opened by the
magnetic field formed at the second valve coil 274. Since the first
safety valve 123 and the second safety valve 124 are both opened
when the second switch 276 is converted to the off-state, gas is
discharged through the gas outlet 126. The discharged gas is mixed
with air in the mixing tube 131, and the gas mixed with air is
ignited by the igniter 132 having a temperature higher than the
ignition point of the gas. Here, the output control valve 125
operates in the high heating power mode. Specifically, the output
control valve 125 may maintain the first open rate and discharge
gas with the maximum output, thus facilitating gas ignition.
[0079] The control unit 270 controls the overall operation of the
clothing dryer 1. The control unit 270 may be one or more
processors. Here, the one or more processors may be implemented by
a plurality of arrays of logic gates or by a combination of a
universal microprocessor and a memory in which a program capable of
being executed in the microprocessor is stored. The control unit
270 may control operation units to dry the object to be dried. The
control unit 270 may operate each configuration in accordance with
a drying algorithm stored in the storage unit 240. Specifically,
the control unit 270 may operate each configuration in accordance
with a drying algorithm corresponding to a drying course input
through the control panel 230.
[0080] In addition, the control unit 270 may control each
configuration based on a state of the clothing dryer 1 detected in
the state detection unit 220. Specifically, the control unit 270
may control the operation mode of the combustion device 100 based
on values detected in the first temperature sensor 49 and the
second temperature sensor 59. In addition, the control unit 270 may
determine the amount of objects to be dried based on the dryness
level detected in the dryness level detection unit 210, and perform
a drying algorithm in accordance with the amount of the objects to
be dried. Also, the control unit 270 may analyze drying
characteristics of the object to be dried, and perform a drying
algorithm in accordance with the analyzed drying characteristics of
the object to be dried. For example, the control unit 270 may
determine a temperature of hot air or determine a time at which the
hot air will be supplied in accordance With the drying
characteristics of the object to be dried. Hereinafter, a method of
controlling a clothing dryer will be described in detail with
reference to FIG. 13.
[0081] FIG. 13 is a flow chart for describing an embodiment of a
method of controlling the clothing dryer according to an
embodiment. FIG. 14 is a view for describing an air flow in a
drying process of the clothing dryer according to an embodiment.
Referring to FIGS. 2, 9, and 13, the user may insert an object to
be dried into the drum 20 and use the control panel 230 to set a
drying course at step 510. Here, the drying course may be
classified in accordance with the type of the object to be dried,
but is not limited thereto. For example, the drying course may also
be classified in accordance with the target dryness level,
characteristics of the object to be dried, etc.
[0082] The clothing dryer 1 determines whether an operation command
has been input from the user at step 520. When a drying command is
input (YES at step 520), the clothing dryer 1 measures the amount
of the objects to be dried at step 530. Although there are no
limitations to a method of measuring the amount of the object to be
dried, the amount of the objects to be dried may be measured based
on the dryness level detected in the dryness level detection unit
210. For example, the amount of the objects to be dried may be
determined to be greater as the frequency of the current pulse
generation is higher, and the amount of the objects to be dried may
be determined to be smaller as the frequency of the current pulse
generation is lower. However, measuring the amount of the objects
to be dried may be omitted when the user has input the amount of
the objects to be dried.
[0083] The clothing dryer 1 begins an ignition process at step 540.
Specifically, the control unit 270 may control the valve assembly
120 to discharge gas, and apply a temperature higher than the
ignition point of the gas to the gas being discharged to ignite the
gas. Here, the valve assembly 120 may discharge the gas with the
maximum output. The clothing dryer 1 begins a drying process at
step 550. When the drying process begins, the control unit 270
controls the driving motor 63 to rotate a circulation fan and the
drum 20, and controls the combustion device 100 to heat air. The
air circulates in the drying process as illustrated in FIG. 14.
[0084] Specifically, the gas discharged from the valve assembly 120
is combusted in the combustion chamber 41 after passing through the
mixing tube 131. The air around the combustion chamber 41 is heated
by the combustion of gas. The heated air is introduced into the
drum 20 along the rear duct 43. The air introduced into the drum as
above absorbs the moisture of the object to be dried which is
lifted and lowered repetitively. The air that has absorbed the
moisture is suctioned by the blowing device 60 and discharged
through an exhaust tube. The pressure in the drum 20 decreases as
the humid air in the drum 20 is discharged to the outside as above,
thus further accelerating the introduction of the air heated in the
combustion chamber 41.
[0085] The clothing dryer 1 begins a cooling process at step 560.
Since the object to be dried is dried by the hot air generated in
the combustion chamber 41, the temperature of the object to be
dried is higher when drying is finished. Thus, the temperature in
the drum 20 should be lowered through the cooling process. The
control unit 270 may close the safety valves of the valve assembly
120 to stop the combustion of gas, and drive the driving motor 63
to emit the hot air in the drum 20 to the outside. Meanwhile,
although the step 520 is illustrated in FIG. 13 as being performed
before the ignition process, embodiments are not limited thereto.
For example, the step 520 may be performed during the ignition
process or the drying process.
[0086] Hereinafter, an embodiment of an ignition process will be
described in detail with reference to FIG. 15. FIG. 15 is a flow
chart for describing an embodiment of an ignition process in FIG.
10.
[0087] Referring to FIGS. 2, 9, and 15, the clothing dryer 1 opens
the first safety valve 123 at step 511, and heats the igniter 132
at step 512. As illustrated in FIG. 11, when the first switch 271
is converted to the on-state by the control command of the control
unit 270, voltage is applied to the first valve coil 272 and a
magnetic field is generated. The first safety valve 123 is opened
by the magnetic field generated at the first valve coil 272. Also,
when the first switch 271 is converted to the on-state, voltage is
applied to the variable resistor 275, and the igniter 132 is
heated.
[0088] The clothing dryer 1 determines whether the temperature of
the igniter 132 is greater than the ignition temperature at step
513. When the temperature of the igniter 132 reaches the ignition
temperature (YES at step 513), the second safety valve 124 is
opened at step 514. As illustrated in FIG. 12, the igniter 132
reaches the ignition temperature, and the second switch 276 is
converted to the off-state by the igniter 132. When the second
switch 276 is converted to the off-state, voltage is applied to the
second valve coil 274, and the second safety valve 124 is opened by
the magnetic field generated at the second valve coil 274.
[0089] That is, gas is discharged only when both of the first
safety valve 123 and the second safety valve 124 are opened. The
gas discharged to the mixing tube 131 is mixed with air in the
mixing tube 131. Here, since the igniter 132 has the ignition
temperature higher than the ignition point of the gas, the gas
which is mixed with air and discharged begins to be combusted by
the igniter 132. Meanwhile, the clothing dryer 1 may operate in the
high heating power mode at the time of ignition. Specifically, the
output control valve 125 remains opened to maximize the gas
discharge amount. The clothing dryer 1 determines whether the gas
ignition has succeeded at step 515. There are no limitations to a
method of determining whether the gas ignition has succeeded. For
example, the control unit 270 may determine that the gas ignition
has succeeded when the temperature of air detected in the first
temperature sensor 49 is a preset temperature, or determine that
the ignition has succeeded as long as a gas leak is not detected by
the gas sensor 133.
[0090] When the gas ignition is determined to be successful, at
step 516 the clothing dryer 1 closes the output control valve 125.
When the output control valve 125 is closed, the open rate of the
valve assembly 120 decreases, and the gas discharge amount
decreases due to the decrease in the open rate. That is, when the
ignition of the clothing dryer 1 is finished, the operation mode is
changed from the high heating power mode to the low heating power
mode. Meanwhile, when the gas ignition is determined to have
failed, the clothing dryer 1 initializes the safety valves at step
517, and returns to the step 511 and begins the ignition process
again. Specifically, the control unit 270 opens the first switch
271 and closes both of the first safety valve 123 and the second
safety valve 124. In addition, since it is preferable that the gas
discharge amount be set high at the time of ignition, the control
unit 270 opens the output control valve 125 and changes the
operation mode to the high heating power mode.
[0091] FIG. 16 is a view illustrating a temperature change in air
when exhaust blockage has occurred. FIG. 17 is a view for
describing an embodiment of a re-ignition process. Meanwhile, the
clothing dryer 1 may perform the re-ignition process in the drying
process. The re-ignition process may be used in the drying process
for various reasons. For example, the temperature of the hot air
supplied to the drum 20 may be excessively high and the combustion
may be stopped to prevent the object to be dried from being
damaged. The re-ignition process can be used when the combustion is
stopped as the above. In addition, the combustion may be stopped
unintentionally due to exhaust blockage, etc. The control unit 270
may detect an unintentional stop of the combustion due to the
exhaust blockage, etc. and perform re-ignition.
[0092] For example, when a temperature value detected in the first
temperature sensor 49 drops below a combustion determination
temperature F as illustrated in FIG. 16, it may be determined that
the combustion has stopped and the re-ignition process may begin.
Here, the combustion determination temperature F may be preset.
Hereinafter, the re-ignition process will be described while
focusing on differences with the ignition process.
[0093] Referring to FIG. 17, the clothing dryer 1 initializes valve
states at step 611. Since the valve states when the combustion is
finished are unclear, the control unit 270 controls the valve
states to be initialized. Specifically, the control unit 270 closes
the first safety valve 123 and the second safety valve 124 and
opens the output control valve 125 to control the clothing dryer 1
to operate in the high heating power mode. The clothing dryer 1
opens the first safety valve 123 at step 612, and heats the igniter
132 at step 613. When the temperature of the igniter 132 becomes
greater than the ignition temperature (YES at step 614), the second
safety valve 124 is opened at step 615. When the second safety
valve 124 is opened, gas is discharged to the mixing tube, and the
discharged gas is ignited by the igniter 132.
[0094] When it is determined that the gas ignition has succeeded
(YES at step 616), the clothing dryer 1 closes the output control
valve 125 at step 617. That is, the operation mode may be changed
from the high heating power mode to the low heating power mode when
the ignition is finished. However, the high heating power mode may
be continuously maintained as needed. Meanwhile, when it is
determined that the gas ignition has failed, the clothing dryer 1
initializes the valve states again at step 611. The clothing dryer
1 may control the valve assembly 120 to control combustion modes.
Hereinafter, the drying process will be described in detail. FIG.
18 is a flow chart for describing in detail an embodiment of the
drying process in FIG. 13. FIG. 19 is a graph illustrating a change
in open rates in the drying process of FIG. 18.
[0095] Referring to FIG. 18, the clothing dryer 1 dries the object
to be dried in the low heating power mode at step 621. At an
initial stage of drying, the object to be dried contains a great
amount of moisture. When the object to be dried contains a great
amount of moisture, the moisture of the object to be dried may be
efficiently removed even when low-temperature hot air is used.
Thus, the clothing dryer 1 may operate in the low heating power
mode at the initial stage of drying, thus increasing the gas
efficiency of the clothing dryer 1.
[0096] The valve assembly 120 maintains a first open rate 01 in the
low heating power mode as illustrated in FIG. 19 and discharges a
smaller amount of gas compared to the high heating power mode.
Here, the first open rate O1 may be 50% or less of a second open
rate O2. For example, the first open rate O1 may be 30%.
Specifically, the output control valve 125 maintains the on-state
in the low heating power mode. When the output control valve 125 is
turned on, the orifice 125b moves forward into the gas flow passage
129. When the orifice 125b moves forward into the gas flow passage
129, the gas flow passage 129 is closed by the orifice 125b, and
the gas moves along the inner flow passage 125c provided in the
orifice 125b. When the open rate of the gas flow passage 129
becomes the first open rate as above, the amount of gas discharged
to the mixing tube 131 also decreases, such that the heating power
of the combustion device 100 decreases and the hot air of low
temperature is generated.
[0097] The clothing dryer 1 detects the dryness level of the object
to be dried at step 622. The dryness level detection unit 210 may
detect the dryness level every predetermined period. For example,
the dryness level detection unit 210 may count a number of
operation pulses generated during a predetermined time (such as one
minute) and calculate the dryness level of the object to be dried
based on the number of operation pulses generated. The clothing
dryer 1 determines whether the detected dryness level is below the
reference dryness level at step 623. When the amount of moisture
contained in the object to be dried drops below a predetermined
level by the low heating power mode, the object to be dried is not
dried well with the hot air of low temperature. As above, the
dryness level at which the object to be dried is not dried well
with the hot air of low temperature is referred to as the reference
dryness level. The reference dryness level may be preset, and may
be set differently in accordance with the amount of the objects to
be dried and the characteristics of the object to be dried.
[0098] When the detected dryness level is below the reference
dryness level (YES at step 623), the clothing dryer 1 is converted
to the high heating power mode at step 624. The control unit 270
opens the output control valve 125. As illustrated in FIG. 8, the
orifice 125b that was blocking the flow passage moves backward
toward the valve body 125a when the output control valve 125 is
opened. When the orifice 125b moves backward, the open rate of the
gas flow passage 129 increases. When the open rate of the gas flow
passage 129 increases, the amount of gas discharged to the mixing
tube 131 increases, such that the heating power of the combustion
device 100 increases and hot air of high temperature is
generated.
[0099] The clothing dryer 1 detects the dryness level of the object
to be dried at step 625, and determines whether the detected
dryness level is below the target dryness level at step 626. When
the detected dryness level is below the target dryness level (YES
at step 626), the clothing dryer 1 closes the safety valves at step
627. When the safety valves are closed, the gas discharge stops.
Also, the clothing dryer 1 performs the cooling process of cooling
the object to be dried. That is, the clothing dryer 1 is converted
to the standby mode. Here, the target dryness level refers to the
dryness level at which drying is finished, and may be preset. Same
as the reference dryness level, the target dryness level may also
be set differently in accordance with the amount of the objects to
be dried or the characteristics of the object to be dried. In
addition, the target dryness level may also be set differently for
each drying course. For example, the target dryness level may be
set higher than that of a normal drying course when an anti-wrinkle
function is selected in order to prevent the object to be dried
from being wrinkled.
[0100] Meanwhile, although it has been described in FIG. 18 that
the drying process is performed based on a change in the dryness
level, the drying process may also be performed based on time.
Hereinafter, a drying process performed based on time will be
described with reference to FIG. 20. FIG. 20 is a flow chart for
describing in detail another embodiment of the drying process in
FIG. 13. Hereinafter, another embodiment of the drying process will
be described while focusing on differences from that in FIG. 18.
The clothing dryer 1 dries the object to be dried in the low
heating power mode at step 631. As illustrated in FIG. 19, the
output control valve 125 is turned on and the open rate of the
valve assembly 120 is set as the first open rate in the low heating
power mode. The clothing dryer 1 determines whether a
low-temperature drying time has elapsed at step 632.
[0101] When the low-temperature drying time has elapsed (YES at
step 632), the clothing dryer 1 dries the object to be dried in the
high heating power mode at step 633. Here, the low-temperature
drying time may be preset. In addition, the low-temperature drying
time may be set differently in accordance with the amount of the
objects to be dried or the dryness level detected at the initial
stage of drying. For example, the low-temperature drying time may
be set longer as the amount of the objects to be dried is greater,
or set shorter as the dryness level detected at the initial stage
of drying is higher.
[0102] The clothing dryer 1 determines whether a high-temperature
drying time has elapsed at step 634. As illustrated in FIG. 19, the
output control valve 125 is turned off and the open rate of the
valve assembly 120 increases from the first open rate to the second
open rate in the high heating power mode. Here, the second open
rate may be 100% at maximum. When the high-temperature drying time
has elapsed (YES at step 634), the clothing dryer 1 closes the
safety valves at step 635. That is, the clothing dryer 1 is
converted to the standby mode. Here, the high-temperature drying
time may be preset. In addition, the high-temperature drying time
may be set differently in accordance with the amount of the objects
to be dried or the dryness level detected at the initial stage of
drying. For example, the high-temperature drying time may be set
longer as the amount of the objects to be dried is greater, or set
shorter as the dryness level detected at the initial stage of
drying is higher. In addition, the high-temperature drying time may
be set differently in accordance with the change in the dryness
level. For example, when the change in the dryness level is great,
the control unit 270 may determine that the object to be dried may
be easily dried and set the high-temperature drying time to be
short.
[0103] Meanwhile, although it has been described in FIG. 20 that
the drying process is performed in accordance with a preset time,
the drying process may also be performed using a combination of the
dryness level and the time. For example, the clothing dryer 1 may
be converted from the low heating power mode to the high heating
power mode when one of the preset reference dryness level condition
and the low-temperature drying time condition is satisfied, or
converted from the low heating power mode to the high heating power
mode when both of the reference dryness level condition and the
low-temperature drying time condition are satisfied. In addition,
the high heating power mode may end when one of the preset target
dryness level condition and the high-temperature drying time
condition is satisfied, or the high heating power mode may end when
both of the target dryness level condition and the high-temperature
drying time condition are satisfied.
[0104] Hereinafter, an embodiment of a drying process which uses a
combination of the dryness level and time conditions will be
described with reference to FIG. 21. FIG. 21 is a flow chart for
describing in detail still another embodiment of the drying process
in FIG. 13. Referring to FIG. 21, the clothing dryer 1 dries object
to be dried in the low heating power mode at step 641. The clothing
dryer 1 detects the dryness level of the object to be dried at step
642, and determines whether the detected dryness level is below the
reference dryness level at step 643. When the detected dryness
level is below the reference dryness level (YES at step 643), the
clothing dryer 1 dries the object to be dried in the high heating
power mode at step 644. The clothing dryer 1 determines whether the
high-temperature drying time has elapsed at step 645, and when the
high-temperature time has elapsed (YES at step 645), the clothing
dryer 1 closes the safety valves at step 646. Here, the
high-temperature drying time may be determined by the change in the
dryness level in the low heating power mode.
[0105] FIG. 22 is a view for describing another embodiment of mode
change in the drying process. Although it has been described though
FIGS. 19 to 21 that the drying process is classified as the low
heating power mode which generates the low-temperature hot air in
accordance with the first open rate and the high heating power mode
which generates the high-temperature hot air in accordance with the
second open rate, the modes of the drying process are not limited
thereto. That is, as illustrated in FIG. 22, the drying process may
be configured of more operation modes. Specifically, the drying
process may include a first heating power mode which discharges gas
at the open rate of 30%, a second heating power mode which
discharges gas at the open rate of 60%, and a third heating power
mode which discharges gas at the open rate of 100%.
[0106] Here, the valve assembly 120 may include a plurality of
output control valves 125. For example, the valve assembly 120 may
include a first output control valve which lowers the open rate to
30% and a second output control valve which lowers the open rate to
60%. Meanwhile, although it has been described through FIGS. 19 to
21 that the valve assembly 120 maintains the first open rate in the
low heating power mode and maintains the second open rate in the
high heating power mode, embodiments are not limited thereto.
[0107] In one embodiment, when a temperature detected in the first
temperature sensor 49 is greater than a first preset critical
temperature, the valve assembly 120 may be controlled such that the
heating power decreases. The first critical temperature refers to a
temperature at which the object to be dried may be damaged. The
first critical temperature may be set differently in accordance
with the type of the object to be dried. Specifically, the clothing
dryer 1 may be converted from the high heating power mode to the
low heating power mode when the temperature of air introduced into
the drum 20 becomes greater than the first critical temperature, or
converted from the low heating power mode to the standby mode to
prevent damage to the object to be dried.
[0108] In another embodiment, when the temperature detected in the
first temperature sensor 49 drops below a preset second critical
temperature, the clothing dryer 1 may increase the heating power.
The second critical temperature refers to a temperature at which
the drying efficiency of the object to be dried decreases, and may
be set differently in accordance with the type of the object to be
dried. Specifically, the clothing dryer 1 may be converted from the
standby mode to the low heating power mode or the high heating
power mode when the temperature of air introduced into the drum 20
becomes lower than the second critical temperature, or converted
from the low heating power mode to the high heating power mode to
increase the drying efficiency.
[0109] FIG. 23 is a view for describing a control for tracking a
temperature. FIG. 24 is a view for describing the drying process
which limits an output based on the temperature. In still another
embodiment, the clothing dryer 1 may perform the drying process by
tracking a preset temperature. Since drying is well-performed even
if hot air of a relatively low temperature is supplied at the
initial stage of drying, the clothing dryer 1 may operate in a low
temperature mode which maintains a low temperature at the initial
stage of drying and operate in a high temperature mode which
maintains a high temperature after drying is performed to some
extent as illustrated in FIG. 23. The clothing dryer 1 may control
a combustion mode such that hot air of a preset low temperature
(such as 35.degree. C.) is generated in the low temperature mode,
and control the combustion mode such that hot air of a preset high
temperature (such as 55.degree. C.) is generated in the high
temperature mode. Specifically, the control unit 270 may change the
operation mode to increase the heating power when the actual
temperature of hot air is lower than a preset temperature of hot
air and change the operation mode to decrease the heating power
when the actual temperature of hot air is higher than the preset
temperature of hot air, thus tracking the preset hot air
temperature. Hereinafter, a method of tracking the hot air
temperature by controlling the operation mode will be described in
detail with reference to FIGS. 24 and 25.
[0110] Referring to FIGS. 23 and 24, the clothing dryer 1 detects a
temperature of hot air at step 711. Since the hot air generated by
the combustion device 100 is supplied to the drum 20 along the rear
flow passage 44, the clothing dryer 1 may detect the temperature of
hot air using the first temperature sensor 49, but the method of
detecting the hot air temperature is not limited thereto. The
clothing dryer 1 determines whether the hot air temperature is
lower than a first critical temperature t1 at step 712. The first
critical temperature tl refers to a minimum maintenance temperature
and may be set differently in the low temperature mode and the high
temperature mode. For example, the first critical temperature tl
may be set as al in the low temperature mode and a3 in the high
temperature mode. When the hot air temperature is below the first
critical temperature t1 (YES at step 712), the clothing dryer 1
turns off the output control valve 125 at step 713. That is, the
clothing dryer 1 converts the output control valve 125 to the
off-state and increases the open rate of the valve assembly 120 to
change from the low heating power mode to the high heating power
mode. Since the gas discharge amount increases when the operation
mode is changed from the low heating power mode to the high heating
power mode, the heating power of the combustion device 100
increases and the hot air temperature also increases.
[0111] When the hot air temperature is higher than the first
critical temperature tl (NO at step 712), the clothing dryer 1
determines whether the hot air temperature exceeds a second
critical temperature t2 at step 714. The second critical
temperature t2 refers to the maximum maintenance temperature and
may be set differently in the low temperature mode and the high
temperature mode. For example, the second critical temperature may
be set as a2 in the low temperature mode and a4 in the high
temperature mode. Meanwhile, when the hot air temperature is lower
than the second critical temperature t2 (NO at step 714), the
clothing dryer 1 detects the hot air temperature again at step 711.
That is, the clothing dryer 1 may determine that the hot air
temperature is within a reference range and maintain the heating
power. When the hot air temperature exceeds the second critical
temperature t2 (YES at step 714), the clothing dryer 1 determines
whether the output control valve 125 is open at step 715. When the
output control valve 125 is determined to be opened (YES at step
715), the clothing dryer 1 closes the output control valve 125 at
step 716 and detects the hot air temperature again at step 711.
That is, the clothing dryer 1 may control the output control valve
125 to be turned on and decrease the open rate. Since the gas
discharge amount decreases when the open rate decreases, the
heating power of the combustion device 100 decreases and the hot
air temperature also drops. That is, the clothing dryer 1 is
converted from the high heating power mode to the low heating power
mode.
[0112] Meanwhile, when the output control valve 125 is determined
to be closed (NO at step 715), the clothing dryer 1 closes the
safety valves at step 717, and re-ignites after a predetermined
amount of time at step 718. The object to be dried may be protected
by extinguishing the combustion device 100 as above. That is, the
clothing dryer 1 is converted from the low heating power mode to
the standby mode. Meanwhile, each parameter of the drying process
may be adjusted in accordance with a change in a dried amount.
Hereinafter, this will be described in detail. FIG. 25 is a flow
chart for describing an embodiment of analyzing characteristics of
an object to be dried. FIG. 26 is a view for describing a change in
a dryness level in accordance with the characteristics of an object
to be dried.
[0113] Referring to FIGS. 25 and 26, the clothing dryer 1 measures
a first dryness level at step 801. As illustrated in FIG. 26, the
first dryness level may be measured at a first preset time Q1. The
clothing dryer 1 measures a second dryness level at step 802. As
illustrated in FIG. 26, the second dryness level may be measured at
a second preset time Q2. The clothing dryer 1 analyzes
characteristics of an object to be dried based on the first dryness
level and the second dryness level at step 803. Specifically, the
control unit 270 detects a change in the dryness level based on the
first dryness level and the second dryness level, and analyzes the
characteristics of the object to be dried. That is, a dryness
characteristic of the object to be dried may be analyzed. The
clothing dryer 1 adjusts parameters based on the characteristics of
the object to be dried at step 804. Here, the parameters refer to
various types of variables such as the above-mentioned reference
dryness level, target dryness level, low-temperature drying time,
high-temperature drying time, critical temperature, and the like
which can be used for the drying process.
[0114] For example, the clothing dryer 1 may analyze the object to
be dried having a rapid change in dryness level such as D1
illustrated in FIG. 26 as a synthetic fiber, and revise the
low-temperature drying time and the high-temperature drying time to
be shorter. In addition, since the synthetic fiber is vulnerable to
heat, the critical temperature of hot air may be set lower to
prevent the synthetic fiber from being damaged by the hot air. In
addition, the clothing dryer 1 may determine that the object to be
dried having a slow change in dryness level such as D2 illustrated
in FIG. 26 uses additional drying, and increase the
high-temperature drying time or set the reference dryness level or
the target dryness level to be lower.
[0115] As described above, since heating power is controlled in
accordance with predetermined open rates, gas efficiency may be
increased. In addition, a valve assembly is controlled by only the
predetermined open rates, thus facilitating the heating power
control.
[0116] Although the present disclosure has been described with an
exemplary embodiment, 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.
* * * * *