U.S. patent application number 13/096395 was filed with the patent office on 2011-11-17 for control method of dryer.
Invention is credited to Sangik Lee, Yongju Lee, Hyunwoo Noh.
Application Number | 20110280736 13/096395 |
Document ID | / |
Family ID | 44862072 |
Filed Date | 2011-11-17 |
United States Patent
Application |
20110280736 |
Kind Code |
A1 |
Lee; Yongju ; et
al. |
November 17, 2011 |
CONTROL METHOD OF DRYER
Abstract
A control method of a dryer is disclosed. A control method of a
dryer including a heat pump having a variable velocity type
compressor, the control method includes steps of selecting at least
one course supplying air or dried air; increasing an activation
velocity of the compressor to a target velocity, as the selected
course is implemented; and adjusting an open degree of an expansion
valve provided in the heat pump.
Inventors: |
Lee; Yongju; (Changwon-si,
KR) ; Lee; Sangik; (Changwon-si, KR) ; Noh;
Hyunwoo; (Changwon-si, KR) |
Family ID: |
44862072 |
Appl. No.: |
13/096395 |
Filed: |
April 28, 2011 |
Current U.S.
Class: |
417/26 |
Current CPC
Class: |
F04B 2203/0209 20130101;
Y02B 40/00 20130101; D06F 2103/50 20200201; D06F 58/206 20130101;
D06F 58/30 20200201; F04B 49/03 20130101; D06F 2105/26
20200201 |
Class at
Publication: |
417/26 |
International
Class: |
F04B 49/00 20060101
F04B049/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 28, 2010 |
KR |
10-2010-0039371 |
Apr 28, 2010 |
KR |
10-2010-0039372 |
Apr 28, 2010 |
KR |
10-2010-0039373 |
May 4, 2010 |
KR |
10-2010-0041999 |
Claims
1. A control method of a dryer comprising a heat pump including a
variable velocity type compressor, the control method comprising
steps of: selecting at least one course set to supply air or dried
air; increasing an activation velocity of the compressor to a
target velocity, as the selected course is implemented; and
adjusting an open degree of an expansion valve provided in the heat
pump.
2. The control method of the dryer as claimed in claim 1, wherein
the step of increasing the activation velocity of the compressor to
the target velocity is performed for a first time band.
3. The control method of the dryer as claimed in claim 2, wherein
an open degree of the expansion valve is maintained at a maximum
value for the first time band.
4. The control method of the dryer as claimed in claim 2, further
comprising steps of: opening the expansion valve at a maximum
degree for the first time band; and closing the expansion valve by
adjusting the open degree of the expansion valve for the first time
band.
5. The control method of the dryer as claimed in claim 4, wherein
the expansion valve is closed by adjusting the open degree of the
expansion valve a predetermined time after the first time band
starts.
6. The control method of the dryer as claimed in claim 2, wherein
the activation velocity of the compressor is gradually increased
for the first time band.
7. The control method of the dryer as claimed in claim 2, wherein
the activation velocity of the compressor is serially increased for
the first time band.
8. The control method of the dryer as claimed in claim 7, wherein
the activation velocity of the compressor is serially increased
along a predetermined curvature.
9. The control method of the dryer as claimed in claim 8, wherein a
slope of the curvature in a first half of the first time band is
larger than a slope of the curvature in a second half of the first
time band.
10. The control method of the dryer as claimed in claim 1, wherein
the step of adjusting the open degree of the expansion valve is
performed for a second time band.
11. The control method of the dryer as claimed in claim 10, wherein
the expansion valve is closed gradually.
12. The control method of the dryer as claimed in claim 11, wherein
the expansion valve is closed based on at least one piece of
temperature information relating to the heat pump.
13. The control method of the dryer as claimed in claim 12, wherein
the temperature information relating to the heat pump comprises at
least one of a temperature of a refrigerant circulating the heat
pump and a temperature of an evaporator, a temperature of a
compressor and a temperature of a condenser which are provided in
the heat pump.
14. The control method of the dryer as claimed in claim 12, wherein
the expansion valve is closed gradually when the at least one piece
of the temperature information relating to the heat pump is
increased to a preset value or more.
15. The control method of the dryer as claimed in claim 10, wherein
an activation velocity of the compressor is maintained to be the
target velocity for the second time band.
16. The control method of the dryer as claimed in claim 10, wherein
an activation velocity of the compressor is adjusted for the second
time band.
17. The control method of the dryer as claimed in claim 1, further
comprising steps of: identifying a low noisy activation condition
of the dryer while a selected course is implemented; and adjusting
an activation velocity of the compressor based on the low noisy
activation condition.
18. The control method of the dryer as claimed in claim 17, wherein
the low noisy activation condition of the dryer is set manually or
automatically.
19. The control method of the dryer as claimed in claim 17, wherein
the low noisy activation condition of the dryer is set based on a
user's selection or an activation time band of the dryer.
20. The control method of the dryer as claimed in claim 19, wherein
the low noisy activation condition of the dryer is set when the
user selects a predetermined course or a predetermined mode.
21. The control method of the dryer as claimed in claim 19, wherein
the low noisy activation condition of the dryer is set when an
activation time band of the dryer belongs to a predetermined time
band.
22. The control method of the dryer as claimed in claim 21, wherein
the low noisy activation condition of the dryer is set when an
activation time band of a variable velocity type compressor
provided in the dryer belongs to a predetermined time band.
23. The control method of the dryer as claimed in claim 17, wherein
the step of adjusting the activation velocity of the variable
velocity type compressor activates the variable velocity type
compressor at a predetermined velocity which is lower than a normal
velocity of the compressor.
24. The control method of the dryer as claimed in claim 17, wherein
the step of adjusting the activation velocity of the variable
velocity type compressor activates the variable velocity type
compressor at a predetermined velocity which allows noise generated
in the compressor to be a preset reference value or lower.
25. A dryer comprising: a user operational part configured to
receive at least one piece of drying information; a control unit
configured to generate an operation signal based on the drying
information input via the user operational part; a heat pump
activated based on the operation signal generated in the control
unit, the heat pump comprising a compressor and an expansion valve,
wherein an activation velocity of the compressor is increased to a
preset target velocity based on the operation signal for a first
time band and an open degree of the expansion valve is adjusted
based on the operation signal for a second time band which is in a
serial order with the first time band
26. The dryer as claimed in claim 25, wherein the second time band
is partially overlapped with the first time band.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] Pursuant to 35 U.S.C. .sctn.119(a), this application claims
the benefit of earlier filing date and right of priority to Korean
Patent Application Nos. 10-2010-0039371 filed on Apr. 28, 2010,
10-2010-0039372 filed on Apr. 28, 2010, 10-2010-0039373 filed on
Apr. 28, 2010 and 10-2010-0041999 filed on May 4, 2010, which are
hereby incorporated by references as if fully set forth herein.
BACKGROUND OF THE DISCLOSURE
[0002] 1. Field of the Disclosure
[0003] The present invention relates to a control method of a
dryer.
[0004] 2. Discussion of the Related Art
[0005] Laundry devices may be categorized into washing machines
which can perform washing, dryers which can perform drying and
washing machines having a drying function which can perform both
washing and drying. Dryers are electric appliances which supply
heated dry air to drying objects to dry them. A variety of dryers
have been developed and the dryers accompany a variety of
problems.
SUMMARY OF THE DISCLOSURE
[0006] Accordingly, the present invention is directed to a control
method of a dryer.
[0007] An object of the present invention is to provide a control
method of a dryer which can activate a compressor in initial
activation stably. In other words, the object of the present
invention is to provide the control method which can prevent liquid
refrigerant from flowing into the compressor in the initial
activation of the compressor. By extension, the object of the
present invention is to provide the control method which can
control the quantity of the refrigerant based on temperature
information relating to the compressor, to prevent overheat of the
compressor.
[0008] Furthermore, another object of the present invention is to
provide a control method which can reduce noise and vibration of a
dryer. For that, the control method according to the present
invention may adjust an activation velocity of a variable velocity
type compressor, to reduce the noise and vibration generated in the
compressor.
[0009] Additional advantages, objects, and features of the
disclosure will be set forth in part in the description which
follows and in part will become apparent to those having ordinary
skill in the art upon examination of the following or may be
learned from practice of the invention. The objectives and other
advantages of the invention may be realized and attained by the
structure particularly pointed out in the written description and
claims hereof as well as the appended drawings.
[0010] To achieve these objects and other advantages and in
accordance with the purpose of the invention, as embodied and
broadly described herein, a control method of a dryer comprising a
heat pump including a variable velocity type compressor, the
control method includes steps of: selecting at least one course
supplying air or dried air; increasing an activation velocity of
the compressor to a target velocity, as the selected course is
implemented; and adjusting an open degree of an expansion valve
provided in the heat pump.
[0011] In another aspect of the present invention, a dryer includes
a user operational part configured to receive at least one piece of
drying information; a control unit configured to generate an
operation signal based on the drying information input via the user
operational part; a heat pump activated based on the operation
signal generated in the control unit, the heat pump comprising a
compressor and an expansion valve, wherein an activation velocity
of the compressor is increased to a preset target velocity for a
first time band based on the operation signal and an open degree of
the expansion valve is adjusted based on the operation signal for a
first time band and a second time band in a serial order.
[0012] It is to be understood that both the foregoing general
description and the following detailed description of the present
invention are exemplary and explanatory and are intended to provide
further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings, which are included to provide a
further understanding of the disclosure and are incorporated in and
constitute a part of this application, illustrate embodiment(s) of
the disclosure and together with the description serve to explain
the principle of the disclosure.
[0014] In the drawings:
[0015] FIG. 1 is a perspective view illustrating an inner
configuration of a dryer according to an exemplary embodiment of
the present invention;
[0016] FIG. 2 is a perspective view only illustrating a heat pump
from FIG. 1;
[0017] FIGS. 3 to 6 are diagram schematically illustrating a
configuration of a dryer including a heat pump according to
embodiments;
[0018] FIGS. 7 and 8 are diagram illustrating a configuration of a
heat pump according to another embodiments; and
[0019] FIGS. 9 and 10 are graphs illustrating driving velocity
change of a compressor according to the control method;
[0020] FIG. 11 is a graph illustrating opening degree change of an
expansion valve according to the control method;
[0021] FIG. 12 is a flow chart illustrating a control method
according to another embodiment;
[0022] FIG. 13 is a graph illustrating a relation between a driving
time brand and a low noise time band of a compressor; and
[0023] FIG. 14 is a graph illustrating noise based on a driving
velocity of the compressor.
DESCRIPTION OF SPECIFIC EMBODIMENTS
[0024] Reference will now be made in detail to the specific
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings. Wherever possible, the
same reference numbers will be used throughout the drawings to
refer to the same or like parts.
[0025] As follows, a dryer according to an exemplary embodiment of
the present invention will be described in detail in reference to
the accompanying drawings.
[0026] FIG. 1 is a perspective view illustrating a dryer according
to an exemplary embodiment of the present invention.
[0027] In reference to FIG. 1, the dryer 100 according to the
embodiment of the present invention includes a cabinet 110 forming
an exterior appearance thereof. The dryer 100 further includes a
drum 120 which is selectively rotatable within the cabinet 110.
Drying objects may be loaded into the drum 120. Although not shown
in the drawings, the dryer 100 may include a user operational part
(not shown) to receive at least one piece of drying information
input by a user. The user may use the user operational part to
select pieces of the drying information, for example, a wished
course. The dryer 100 includes a control unit (not shown)
generating an operation signal based on the drying information
input via the user operational part.
[0028] In the meanwhile, the dryer 100 according to the embodiment
may include heating means for supplying dried-air to the drum 120
to dry the drying objects loaded into the drum 120. The dryer 100
according to this embodiment may include a heat pump 130 as the
heating means. The heat pump 130 includes an evaporator 132, a
compressor (134, see FIG. 3), a condenser 136 and an expansion
valve (138, see FIG. 3) where refrigerant is circulated
sequentially. The heat pump 130 may dehumidify and dry external air
drawn therein and it may heat the dried air to a predetermined
temperature. Here, the heat pump 130 is activated based on the
operation signal of the control unit.
[0029] As follows, the heat pump 130 will be described in
detail.
[0030] FIG. 2 is a perspective view illustrating the configuration
of the heat pump 130 according to an embodiment.
[0031] In reference to FIG. 2, the heat pump 130 includes an
evaporator 132 and a condenser 136. The evaporator 132 condenses
refrigerant, to receive a latent heat from the external air drawn
therein and it condenses the moisture of the air, to transmit the
latent heat to the condenser 136. The condenser 136 heats the air
by using the latent heat transmitted from the evaporator 132 via
the refrigerant. In other words, the heat pump 130 according to
this embodiment controls the evaporator 132 to dehumidify air and
the condenser 136 to heat the air to the predetermined temperature,
such that it may supply dried/heated air to the drum 120.
[0032] In the meanwhile, each component of the heat pump 130
mentioned above may be installed in a predetermined portion of the
cabinet 110 provided in the dryer 100 according to the exemplary
embodiment. It is preferable that the heat pump 130 may be a module
type mounted in a predetermined portion of the cabinet 110
detachably. The module type heat pump 130 is provided and it is
then more efficient to assemble and disassemble the dryer according
to this embodiment for maintenance. For that, the heat pump 130
according to this embodiment may include a case 140 for forming a
profile of the heat pump 130 and the variety of the components
mentioned above may be provided in the case 140.
[0033] The case 140 may include an upper case 142 and a lower case
144. The various components of the heat pump 130 may be installed
in the lower case 144. The upper case 142 may be detachably coupled
to the lower case 144. Because of that, the installation and repair
of the components installed in the case 140 may be performed smooth
and efficient.
[0034] The moisture of the air drawn into the case 140 is condensed
and the air is dried by the evaporator 132. In other words, the
refrigerant is evaporated in a refrigerant pipe of the evaporator
132 and the heat of the air passing outside the evaporator 132 is
transmitted to the refrigerant, to cool the air. The moisture is
condensed into condensate and the air is relieved of the moisture,
to be the dried air.
[0035] It is preferable that a condensate storage (not shown) may
be further provided to collect the condensate condensed by the
evaporator 132. For example, a collecting tank (not shown) is
provided below the evaporator 132 to collect the condensate and the
collecting tank (not shown) may be connected with the condensate
storage located adjacent to the evaporator 132. Because of that,
the condensate condensed by the evaporator 132 may be collected in
the collecting tank first and it may be stored in the condensate
storage via a pipe after that. The condensate storage may be
installed in the cabinet 110 to send the collected condensate
outside the cabinet 120 via a drainage pipe or it may be detachably
installed in the cabinet 110 to allow the user to throw the
condensate outside after detaching.
[0036] In the meanwhile, the evaporator 132 may store the latent
heat in the refrigerant. At the same time, it may condense the
moisture of the air and dry the air. In other words, as the
moisture contained in the air is condensed, the refrigerant inside
the evaporator 132 is getting gaseous to contain the latent heat.
The latent heat contained in such the refrigerant is transmitted to
the condenser 136 and it is used to heat the air, which will be
described later.
[0037] In other words, the condenser 136 according to this
embodiment is connected with the evaporator 132 and the compressor
134 via a refrigerant pipe (not shown). Because of that, the
refrigerant including the latent heat inside the evaporator 132 is
supplied to the compressor 134 and the condenser 136 sequentially
via the refrigerant pipe. The refrigerant is condensed in the
condenser 136 and the latent heat is discharged, such that the air
passing the condenser 136 may be heated to a predetermined
temperature. As a result, the evaporator 132 condenses the moisture
contained in the air and it dries the air. Simultaneously, the
evaporator 132 transmits the latent heat generated by the
condensation of the moisture to the condenser 136 via the
refrigerant. The condenser 136 condenses the refrigerant to
discharge the latent heat and it then heats the air.
[0038] In the meanwhile, according to this embodiment, a single air
path (A) may be formed to guide the air along the evaporator 132
and the condenser 136. In other words, the moisture of the air
drawn into the heat pump 130 is condensed and the air is dried.
After that, the dried air passes the compressor 134 and it is then
heated in the condenser 136, such that the heated air may be
supplied to the drum 120. When the single air path (A) is formed,
the air supplied to the drum 120 is heated and dried to result in
improving a drying effect. Typically, the high temperature as well
as the dried air should be supplied to improve the drying
effect.
[0039] The shape of the air path (A) where the air is flowing is
not limited to a specific one. Considering that the heat pump 130
is installed in the cabinet 110, the air path (A) may be formed in
a linear shape. For that, the evaporator 132 and the condenser 136
provided in the heat pump 130 may be arranged linearly along the
air path (A). Because of that, the volume of the heat pump 130 can
be reduced as much as possible and the assembly/disassembly process
of the heat pump 130 may be smooth and efficient. Here, a fan (not
shown) may be further provided in the case 132 to blow the air to
flow along the air path (A) smoothly.
[0040] As mentioned above, this embodiment presents the air path
provided when the case 140 is provided in the heat pump 130.
However, in case the components of the heat pump 130 are installed
in a predetermined portion of the cabinet 110, without the case
140, an auxiliary duct may be provided to draw external air to the
evaporator 132 and the condenser 136. In the meanwhile, if the air
dried and heated by the heat pump 130 is supplied to the drum 120,
the air is heated by the condenser 136. Because of that, the
temperature of the air supplied by the heat pump 130 of the dryer
100 according to this embodiment may be lower than the temperature
of the air supplied by a heater provided in a conventional dryer.
Because of that, the dryer according to this embodiment may further
include a heater (139, see FIG. 4) to heat the air before drawing
the air into the case 140 or the drum 120.
[0041] In addition, this embodiment presents that the single air
path (A) is formed along the evaporator 132 and the condenser 136
of the heat pump 130. Alternatively, independent air paths may be
formed along the evaporator and the condenser. In other words, the
moisture of the air drawn into the evaporator 132 is condensed to
store the latent heat and the air is discharged outside the heat
pump 130 again. The latent heat is transmitted to the condenser 136
via the latent heat and the air drawn into the condenser 136 along
the auxiliary air path may be heated to be supplied to the drum
120.
[0042] In the meanwhile, dryers may be categorized into circulation
type dryers and exhaustion type dryers. In a circulation type uses
air circulated in the drum and such an exhaustion type uses air
exhausted from the drum. As follows, a circulation type dryer
including the heat pump and an exhaustion type dryer including the
heat pump will be described.
[0043] FIG. 3 is a diagram schematically illustrating a
configuration of the circulation type dryer including the heat
pump.
[0044] In reference to FIG. 3, air exhausted from the drum 120 is
supplied to the evaporator 132 along a first air path 12. The
moisture of the air is condensed by the evaporator 132 and the air
flows to the condenser 136 along a second air path 14 to be heated
to a predetermined temperature by the condenser 136. The air having
passed the condenser 136 is re-supplied to the inside of the drum
120 along a third air path 16. Here, the evaporator 132 and the
condenser 136 may be connected with the compressor 134 and the
expansion valve 138 via a refrigerant line 22. The configuration
and operation of the heat pump is explained above and repeated
description will be omitted.
[0045] FIG. 4 is a diagram illustrating a circulation type dryer
according to another embodiment. According to this embodiment, the
air having passed the heat pump is re-heated by a heater 139 before
supplied to the drum and this is a different feature, compared with
the embodiment of FIG. 3. As follows, this embodiment will be
described, focused to the different feature.
[0046] In reference to FIG. 4, the air discharged from the
condenser 136 is circulated along a third air path 16 to be
supplied to inside of the drum 120 via the heater 139. The heater
139 re-heats the air flowing along the third air path 16. Here, the
term of "re-heating" means that the air is heated by the heater 139
secondarily after heated by the condenser 136 firstly.
[0047] Such the heater 139 may be a gas heater or an electric
heater, not limited thereto. When the heater is provided, the air
dried and heated by the condenser 136 of the heat pump is re-heated
by the heater and it is possible to supply the air having a desired
temperature to the drum 120. The air is pre-heated by the condenser
136 and heated by the heater. Because of that, load applied to the
heater may be reduced noticeably. In other words, the heater uses
less electric energy to heat the air to the desired temperature,
compared with the heater provided in the conventional dryer, and it
is possible to heat the air to the desired temperature by using a
compact-sized heater.
[0048] FIG. 5 is a diagram schematically illustrating a
configuration of an exhaustion type dryer including the heat pump.
Compared with the embodiment of FIG. 3, this embodiment presents a
different air path and it will be described, focused to this
different feature.
[0049] In reference to FIG. 5, the air having passed the evaporator
132 is exhausted outside the dryer along a fourth air path 17. In
other words, different from the circulation type which supplies the
air having passed the evaporator 132 to the condenser 136, the
exhaustion type dryer exhausts the air outside. In this case, the
air exhausted from the drum 120 has a higher temperature than a
normal temperature air. When the air exhausted from the drum 120
reaches the evaporator 132, the heat is transmitted to the
refrigerant of the evaporator 132 and the latent heat is stored in
the refrigerant. Such the refrigerant is supplied to the condenser
136 along the refrigerant line 22 and the air is heated by the
latent heat in the condenser 136. Here, the air is drawn to the
condenser 136 along a fifth air path 19.
[0050] Not the air exhausted from the drum 120 but internal air or
external air of the dryer is flowing along the fifth air path
19.
[0051] FIG. 6 illustrates an exhaustion type dryer according to
another embodiment including the heat pump. Compared with the
embodiment of FIG. 5, the air having passed the heat pump is
re-heated by a heater 139 before supplied to the drum. The
exhaustion type dryer is described in reference to FIG. 5 and the
heater is described in reference to FIG. 4. Repeated description
will be omitted.
[0052] In the meanwhile, the above embodiments present the heat
pump including the single evaporator and the single condenser.
However, the heat pump may include a plurality of evaporators 132
and a plurality of condensers 136.
[0053] As follows, installation states of the plurality of the
condensers 136 and evaporators 132 will be described. FIGS. 7 and
are diagrams schematically illustrating a heat pump module
including a plurality of condensers 136 and a plurality of
evaporators 132.
[0054] In reference to FIG. 7, the number of the evaporators 132
and the number of the condensers 136 may be determined based on an
installation environment, for example, two evaporators and two
condensers, which will be described as follows.
[0055] The evaporator 132 according to this embodiment includes a
first evaporator 132A and a second evaporator 132B. The condenser
136 includes a first condenser 136A and a second condenser 136B.
The first and second evaporators 132A and 132B may be arranged
adjacent to each other. The first and second condensers 136A and
136B may be also arranged adjacent to each other. Here, the first
and second evaporators and the first and second condensers may be
arranged in parallel to the air path.
[0056] In the meanwhile, the first and second evaporators 132A and
132B and the first and second condensers 136A and 136B are
connected with the compressor 134 by a refrigerant pipe 660. Here,
the connection between the refrigerant pipe and the first and
second evaporators 132A and 132B and the first and second
condensers 136A and 136B may be serial or in parallel.
[0057] Here, when the first and second evaporators 132A and 132B
and the first and second condensers 136A and 136B are connected
with the refrigerant pipe 660 serially, the compressor 134 is
connected with the first evaporator 132A via the refrigerant pipe
660 and the first evaporator 132A is connected with the second
evaporator 132B via an auxiliary pipe. Because of that, the
refrigerant pipe 660 is located from the second evaporator 132B to
the expansion valve 138 and the refrigerant pipe is located from
the expansion valve 138 to the first condenser 136A. Here, the
first condenser 136A is connected with the second condenser 136B
via an auxiliary pipe and the refrigerant pipe 660 is located
between the second condenser 136B and the compressor 134.
[0058] As a result, the refrigerant supplied from the compressor
134 heats the air, while passing the first and second condensers
136A and 136B sequentially. The refrigerant having passed the first
and second condensers 136A and 136B condenses the moisture
contained in the air, while passing the expansion valve 138 and the
first and second evaporators 132A and 132B sequentially.
[0059] In the meanwhile, FIG. 7 shows that the first and second
evaporators 132A and 132B are connected with each other serially
and that the first and second condensers 136A and 136B are
connected with each other serially, too. However, the first and
second evaporators 132A and 132B may be connected in parallel and
the first and second condensers 136A and 136B may be connected in
parallel. FIG. 8 shows the plurality of the evaporators connected
with each other in parallel and the plurality of the condensers
connected with each other in parallel. As follows, the different
feature in comparison to FIG. 7 will be described.
[0060] In reference to FIG. 8, the first and second evaporators
132A and 132B are connected with each other in parallel and the
first and second condensers 136A and 136B are connected with each
other in parallel. In this case, branched pipes 662 and 664 may be
further formed in the refrigerant pipe 660 located from the
compressor 134 to the first and second evaporators 132A and 132B
and in the refrigerant pipe 660 located from the compressor 134 to
the first and second condensers 136A and 136B, respectively. In
addition, branched pipes 666a and 666b may be further formed in the
refrigerant pipe 660 located from the expansion valve 138 to the
first and second evaporators 132A and 132B and in the refrigerant
pipe 660 located from the expansion valve 138 to the first and
second condensers 136A and 136B, respectively.
[0061] The branched pipe 662 is connected to an end of the
refrigerant pipe 660 located between the compressor 134 and the
first and second evaporators 132A and 1132B, such that the
refrigerant may be supplied to the first evaporator 132A and the
second evaporator 132B via the branched pipe 662 simultaneously.
Together with that, the branched pipe 664 is connected to an end of
the refrigerant pipe 660 located between the compressor 134 and the
first and second condensers 136A and 136B, such that the
refrigerant having passed the first and second condensers 136A and
136B may be supplied to the compressor 134 via the branched pipe
664.
[0062] The refrigerant supplied by the compressor 134 condenses the
moisture contained in the air, while dividedly passing the first
and second evaporators 132A and 132B, and it heats the air, while
dividedly passing the first and second condensers 136A and
136B.
[0063] In reference to FIGS. 7 and 8 again, the moisture of the
humid air exhausted from the drum 120 is condensed and removed,
while the air is passing the first and second evaporators 132A and
132B sequentially. After that, the humid air is changed into dried
air. The dried air exhausted from the evaporator 132 is heated
while it is passing the first and second condensers 136A and 136B
sequentially. After that, the high temperature dried air having
passed the second condenser 136B is re-supplied to the inside of
the drum 120. The embodiments of FIGS. 7 and 8 illustrate only the
configuration of the circulation type dryer and they may be
applicable to the exhaustion type dryer. In case of the exhaustion
type, the evaporator and condenser shown in FIGS. 5 and 6 may be
replaced by the plurality of the evaporators and the plurality of
the condensers shown in FIGS. 7 and 8.
[0064] In the meanwhile, the dryer according to the exemplary
embodiment of the present invention has an effect of improved
condensation efficiency, because the humid air exhausted from the
drum 120 passes the first evaporator 132A and the second evaporator
132B sequentially. In other words, the humid air passes the first
and second evaporators 132A and 132B. Because of that, a contact
area and a contact time between the humid air and the refrigerant
line of the first and second evaporators 132A and 132B may be
increased enough to condense the moisture contained in the humid
air as much as possible.
[0065] In addition, the dryer according to the exemplary embodiment
of the present invention has an effect of increased heating
efficiency, because the air passes the first condenser 136A and the
second condenser 136B sequentially. Because of that, a contact area
and a contact time between the dried air and the refrigerant line
of the first and second condensers 136A and 136B may be increased
enough to gain a relatively high temperature dried air, compared
with the dried air passing the single condenser.
[0066] As a result, such the high temperature dried-air is supplied
to the inside of the drum 120 to heat-exchange with the drying
objects. Then, heat-exchanging efficiency can be enhanced and the
drying time can be reduced.
[0067] In the meanwhile, the compressor of the heat pump may
include a fixed velocity type compressor of which a driving
velocity is fixed and a variable velocity type compressor of which
an activation velocity is adjusted. Here, the variable velocity
type compressor may refer to a compressor having a selectively
adjustable activation velocity (hz), not a fixed activation
velocity. As the activation velocity of the compressor 134 is
adjusted, noise and vibration of the compressor 134 may be reduced
and damage and breakdown of the compressor may be prevented.
[0068] However, important elements for adjusting the activation
velocity of the variable velocity type compressor 134 may be
temperature information of the refrigerant. The temperature
information of the refrigerant may include at least one of a
refrigerant condensation temperature of the condenser 136, a
refrigerant evaporation temperature of the evaporator 132, an
exhausted refrigerant temperature of the condenser 136 and
drawn/exhausted refrigerant temperature of the evaporator 132. In
other words, the control unit (not shown) of the dryer 100 may
control an activation velocity of the compressor 134 based on the
temperature information on the refrigerant.
[0069] As follows, a configuration for sensing the temperature of
the heat pump will be described in detail.
[0070] As shown in FIGS. 7 and 8, the heat pump may includes the
evaporator 132, the compressor 134, the condenser 136 and the
expansion valve 138 which are connected with each other via the
refrigerant pipe 660. The dryer according to this embodiment may
include at least one temperature sensor to sense the above
temperature information. When sensing the exhausted refrigerant
temperature of the condenser 136 and the drawn/exhausted
refrigerant temperature of the evaporator 132, temperature sensors
628, 639a and 638b may be provided at a refrigerant outlet hole of
the condenser 136 and refrigerant inlet and outlet holes of the
evaporator 132, respectively. In addition, when sensing an
exhaustion temperature of the compressor 134, a temperature 642 may
be further provided on an outlet hole of the compressor 134.
[0071] In other words, when sensing the exhausted refrigerant
temperature of the condenser 136 and the drawn/exhausted
refrigerant temperature of the evaporator 132, the locations of the
temperature sensors 628, 638a, 638b and 642 may affect the
temperature sensing. However, when sensing the refrigerant
condensation temperature of the condenser 136 and the refrigerant
evaporation temperature of the evaporator 132, the locations of the
temperature sensors 628, 638a and 638b may be important. That is,
to sense a phase change temperature of the refrigerant in the
condenser 136 and the evaporator 132, it is preferable that
temperature sensors 626 and 636 are provided along a line of the
refrigerant line where the phase change is generated inside the
condenser 136 and the evaporator 132.
[0072] In the meanwhile, the evaporator 132 may include a first
temperature sensor 636 to sense the phase change temperature, that
is, the evaporation temperature of the refrigerant in the
evaporator 132 and the evaporator. The first temperature sensor 636
may be provided at a predetermined portion of the evaporator 132 to
sense the phase change temperature of the refrigerant in the
evaporator 132. For example, the first temperature sensor 636 may
be provided at an almost center of the refrigerant line provide
along an inside of the evaporator 132, that is, near a center of
the length of the refrigerant line. This is because the phase
change could be generated near the center portion of the length of
the refrigerant line inside the evaporator 132. When the phase
change of the refrigerant is generated near a refrigerant inlet
hole or a refrigerant outlet hole along the refrigerant line of the
evaporator 132, the refrigerant fails to heat-exchange with the air
sufficiently and entire efficiency of the heat pump might be
deteriorated. As a result, the phase change of the refrigerant may
be generated at the center portion along the length of the
refrigerant line of the evaporator 132 and the first temperature
sensor 636 may be provided adjacent to the center along the length
of the refrigerant line of the evaporator 132, to sense the phase
change temperature of the refrigerant.
[0073] In addition, the condenser 136 may include a second
temperature sensor 626 to sense a phase change temperature of the
refrigerant therein. The second temperature sensor 626 may be
located at a predetermined portion in the condenser 136 to sense
the phase change temperature of the refrigerant in the condenser
136. For example, the second temperature sensor 626 may be provided
adjacent to a center of the refrigerant line provided along the
inside of the condenser 136, that is, adjacent to a center along
the length of the refrigerant line. This is because the phase
change can be generated near the center along the length of the
refrigerant line of the condenser 136. In addition, when the phase
change of the refrigerant is generated near a refrigerant inlet
hole or a refrigerant outlet hole along the refrigerant line of the
condenser 136, the refrigerant fails to heat-exchange with the air
sufficiently and entire efficiency of the heat pump might be
deteriorated. As a result, the phase change of the refrigerant may
be generated at the center portion along the length of the
refrigerant line of the condenser 132 and the second temperature
sensor 626 may be provided adjacent to the center along the length
of the refrigerant line of the condenser 136, to sense the phase
change temperature of the refrigerant.
[0074] Here, when the evaporator 132 and the condenser 136 are
conventional ones, a predetermined length refrigerant line and a
plurality of heat-exchanger fins (not shown) connected with the
refrigerant line to increase heat exchanging efficiency may be
provided. In this case, a center area of the refrigerant line
happens to be overlapped with the heat exchanger fins and it is
difficult to install and secure the first and second temperature
sensors 626 and 636 disadvantageously.
[0075] Because of that, it is preferable that the first and second
temperature sensors 626 and 636 are installed on the refrigerant,
with not overlapped with the heat exchanger fins. In other words,
the first and second temperature sensors 626 and 636 may be
installed at the heat exchanger fins composing the evaporator 132
and the condenser 136 and at the refrigerant line passing the heat
changer fins, with exposed to a predetermined portion of the heat
exchanger fins. Even in this case, the installation locations of
the first and second temperature sensors 626 and 636 may be
adjacent to the center area of the refrigerant line.
[0076] In the meanwhile, the dryer according to the above
embodiments includes the heat pump 130 as air heating/dehumidifying
device. However, in an initial activation of the heat pump 1130
after the activation of the dryer, the refrigerant fails to
heat-exchange with the air in the evaporator 132 and all of the
refrigerant could not be gaseous. Because of that, liquid
refrigerant could be drawn into the compressor 134. If the liquid
refrigerant might be drawn into the compressor, an error and damage
could occur in the compressor. As a result, the dryer including the
compressor may require a control method for preventing the damage
to the compressor in the initial activation of the compressor. As
follows, a control method according to an embodiment will be
described in reference to corresponding drawings.
[0077] FIGS. 9 to 11 are graphs illustrating a control method of
the dryer according to an embodiment. FIGS. 9 and 10 are graphs
illustrating change of an activation velocity of the compressor
based on the time. FIG. 11 is a graph illustrating change of an
opening degree of the expansion valve based on the time. A
horizontal axis shown in FIGS. 9 and 10 refers to the time (t) and
a vertical axis refers to an activation velocity of the compressor.
A horizontal axis shown in FIG. 11 refers to the time (t) and a
vertical axis refers to an open level of the expansion valve.
[0078] In reference to FIG. 9, the control method according to the
embodiment includes steps of increasing an activation velocity of
the compressor to a target velocity and adjusting an opening degree
of the expansion valve. In other words, the dryer the control
method according to the embodiment which will be described can be
applied to may be a dryer including a variable velocity compressor.
In addition, the dryer may include the expansion valve and the
expansion valve may be a type of an expansion valve capable of an
opening degree, for example, a linear expansion valve (LEV). Since
the activation velocity and/or the opening degree of the expansion
valve can be adjusted, the above problem that the liquid
refrigerant might be drawn into the compressor can be prevented,
which will be described in detail as follows.
[0079] Here, the step of the increasing the activation velocity of
the compressor to the target velocity may be performed for a first
time band (T1). The first time band (T1) may start with the
activation of the compressor according to the activation of the
heat pump simultaneously. The heat pump may be activated according
to a selected course when the dryer is put into operation. Because
of that, the control method according to the embodiment may include
a step of selecting at least one course set to supply air or dried
air, prior to the above steps.
[0080] When the activation velocity of the compressor is
drastically increased from an initial stage of the activation, the
liquid refrigerant might be drawn into the compressor as mentioned
above. As a result, the activation velocity of the compressor
according to this embodiment may be increased to the target
velocity gradually, as shown in FIG. 9. In other words, the
activation velocity of the compressor may be increased to the
target velocity by a predetermined unit velocity gradually, not
increased to the target velocity at one time. Because of that, the
liquid refrigerant can be prevented from coming into the
compressor.
[0081] Although FIG. 9 shows only the embodiment presenting that
the activation velocity of the compressor is increased gradually, a
control method according to another embodiment may increase the
activation velocity of the compressor serially and FIG. 10 shows
this embodiments presenting that the activation velocity of the
compressor is increased serially.
[0082] In reference to FIG. 10, the activation velocity of the
compressor may be increased to the target velocity along a
predetermined curvature. In this case, the first time band (T1) is
divided into a first half and a second half. A slope (k1) of the
curvature in the first half may be set relatively larger than a
slope (k2) of the curvature in the second half. In other words, the
activation velocity of the compressor is increased by a relatively
larger value in the first half of the first time band and the
activation velocity of the may be increased by a relatively small
value, corresponding to the target activation velocity.
[0083] In the meanwhile, in case of increasing the activation
velocity of the compressor in the first time band, the expansion
valve may maintain a maximum open state. If the expansion valve is
closed to a predetermined degree, not opened to a maximum degree,
the quantity of the supplied refrigerant is reduced from the
initial stage and the refrigerant cannot perform the condensing and
heating of the moisture contained in the air smoothly. Because of
that, the performance of the heat pump might be deteriorated. To
solve the disadvantage, the control method according to this
embodiment may control the expansion valve to maintain the maximum
open degree and it may adjust the activation velocity of the
compressor, to prevent the liquid refrigerant from being drawn into
the compressor.
[0084] The expansion valve may be adjusted to be closed for a
second time band (T2) following the first time band (T1). The first
time band (T1) and the second time band (T2) may be in a serial
order or a predetermined period of the second time band (T2) is
overlapped with a predetermined period of the first time band (T1).
For the second time band (T2), the open degree of the expansion
valve is decreased gradually to close the expansion valve or it is
adjusted to close the expansion valve. This is because stability of
the compressor has to be maintained when the activation velocity of
the compressor reaches the target velocity.
[0085] In other words, if the compressor is activated at the
reached target velocity, the temperature of the compressor might be
increased abnormally. If the temperature of the compressor is
increased to a predetermined value or more abnormally, there might
be damage or errors of the compressor. Because of that, the open
degree of the expansion valve is decreased to close the expansion
valve to drive the compressor stably and the quantity of the
refrigerant is then decreased, only to prevent the temperature of
the compressor from being increased too high.
[0086] As a result, the control unit may close the expansion valve
gradually based on at least one piece of the temperature
information relating to the heat pump. Here, the at least one piece
of the temperature information relating to the heat pump may
include at least one of the temperature of the refrigerant
circulating the heat pump and the temperatures of the evaporator,
compressor and condenser which compose the heat pump. For example,
the at least one piece of the temperature information may include
at least one of the temperature of the compressor, the temperature
of the refrigerant drawn into the compressor, the temperature of
the refrigerant exhausted from the compressor and the peripheral
temperature of the compressor. Such the temperature information may
be collected from the various temperature sensors described in
reference to FIGS. 7 and 8. As a result, temperature information
relating to the compressor is sensed. When the sensed temperature
increases to a predetermined value or more, the expansion valve may
be controlled to be closed gradually.
[0087] In the meanwhile, the first time band and the second time
band may be arranged in the serial order, not partially overlapped
with each other. In other words, the control unit may control the
expansion valve to be open to the maximum open degree in the first
time band and the activation velocity of the compressor to be
adjusted, to control the activation velocity of the compressor to
reach a desired velocity. After that, in the second time band, the
control unit may control the activation velocity of the compressor
to be maintained at the target velocity and it may adjust the open
degree of the expansion valve to activate the compressor
stably.
[0088] Alternatively, at least a predetermined period of the second
time band (T2) may be overlapped with a predetermined period of the
first time band (T1) as mentioned above. For example, if the
temperature of the compressor is increasing abnormally in the first
time band, it is required to adjust the open degree of the
expansion valve even in the first time band. In this case, after
the step of opening the expansion valve to the maximum open degree
for the first time band (T1), a step of closing the expansion valve
by adjusting an open degree of the compressor may be further
provided. In other words, when assuming that the step of adjusting
the open degree of the expansion valve belongs to the second time
band, it can be said that a time band for the step of adjusting
both the activation velocity of the compressor and the open degree
of the expansion valve is partially overlapped with the first and
second time bands. However, it is preferable that the expansion
valve is closed by adjusting the open degree a predetermined time
after the first time band starts, to prevent the performance of the
heat pump from deteriorating even if the open degree of the
expansion valve is adjusted in the first time band (T1).
[0089] There might be a case that the temperature increase of the
compressor cannot be prevented only by the adjusting of the
expansion valve in the second time band. In this case, it is
required to adjust the activation velocity of the compressor in the
second time band. In other words, not maintaining the activation
velocity of the compressor in the second time band at the target
velocity, the activation velocity of the compressor is adjusted to
be lowered, for example. Even in this case, supposing that the step
of adjusting the activation velocity of the compressor belongs to
the first time band mentioned above, a time band in which the
activation velocity of the compressor and the open degree of the
expansion valve are adjusted together may be partially overlapped
with the first and second time bands.
[0090] In the meanwhile, when the heat pump 130 is provided as
mentioned above, the air heating and dehumidifying may be performed
by the single device. At this time, more noise and vibration might
be generated in comparison to the dryer including the conventional
gas burner or electric heater. In other words, when the compressor
134 of the heat pump 130 is activated, noise and vibration of the
dryer may be increased by the noise and vibration generated by the
activation of the compressor. This increase of the noise and
vibration might give an unpleasant feeling to the user of the
dryer. Especially, the user might be reluctant to use the dyer in
the middle of the night, because of the much noise and vibration.
To reduce such the noise and vibration of the dryer, the activation
noise and vibration of the compressor has to be reduced.
[0091] For that, when the dryer includes the heat pump, the heat
pump may include a variable velocity type compressor. When the
dryer is activated based on the user's selection for reducing the
noise and vibration or in the middle of the night, the activation
velocity of the compressor may be adjusted to reduce the noise and
vibration, for example. As follows, a control method capable of
reducing the noise and vibration of the dryer including the
variable velocity type compressor will be described in detail.
[0092] FIG. 12 is a flow chart illustrating a control method of the
dryer according to another embodiment.
[0093] In reference to FIG. 12, the control method of the dryer may
include steps of: identifying a low noise activation condition of
the dryer (S1210); and adjusting an activation velocity of a
variable velocity type compressor based on the low noisy activation
condition (S1230).
[0094] First of all, when the user selects one of courses provided
in the dryer, the control unit provided in the dryer may identify
`a low noisy activation condition` of the dryer (S1210). In other
words, when the user selects one of the courses, the control unit
may identify a low noisy activation condition during the
implementation of the selected course. Here, `the low noisy
activation condition` refers to a condition set to reduce more
noise when the dryer is activated, compared with a standard course
(or a normal course). Such the condition may be set by the user or
it may be set by the control unit automatically, which will be
described as follows.
[0095] Here, an activation condition of the dryer may be
corresponding to an activation condition of the heat pump, more
exactly, an activation condition of the compressor. Such the low
noisy activation condition may be input by the user manually or
input by the control unit automatically. For example, the user may
select the so-called `low vibration and/or low noise course` and he
or she may input the low noisy activation condition manually.
Alternatively, if the noise and vibration of the dryer has to be a
predetermined value or less, for example, in the middle of the
night, the control unit may identify an activation time band of the
dryer and it may input the low noisy activation condition
automatically.
[0096] If the user tries to input the low noisy activation
condition manually, an auxiliary low vibration and/or low noise
course may be provided in the dryer or the user may select `a low
noise function` additionally after selecting a course. As a result,
when the user selects a predetermined course such as the low
vibration and/or low noise course or a predetermined mode such as
`the low noise function`, the low noisy activation condition may be
input.
[0097] In the meanwhile, when the low noisy activation condition is
automatically input by the control unit, a predetermined time band
(hereinafter, referenced to as `a low noisy time band`) in which
the low noisy activation condition is preset may be input and
stored in the control unit. For example, 7 p.m..about.7 a.m. may be
set in the low noisy time band. When the activation time band of
the dryer is included in the low noisy time band, the control unit
may input the low noisy activation condition automatically. Here,
the low noisy time band may be input and stored in the dryer in
advance, to be output. In addition, the low noisy time band may be
adjusted by the user's selection properly.
[0098] In the meanwhile, if the activation time band of the dryer
is included in the low noisy activation time band, an entire period
of the activation time band may be overlapped with the low noisy
activation time band or a predetermined period of the activation
time band may be overlapped with the low noisy activation time
band. If the entire period of the activation time band is
overlapped with the low noisy activation time band which is the
former case, the control unit may input the low noisy activation
condition automatically.
[0099] However, if the predetermined period of the activation time
band of the dryer is overlapped with the low noisy time band, the
activation condition may be set different based on the overlapped
time band. For example, if the activation time band of the
compressor is included in the predetermined period of the
activation time band of the dryer which is overlapped with the low
noisy time band, the control unit may set the low noisy activation
condition. However, if the activation time band of the compressor
is not provided in the predetermined period of the activation time
band of the dryer which is overlapped with the low noisy time band,
the control unit may not set the low noisy activation condition. In
other words, only when the activation time band of the compressor
is included in the low noisy time band, the control unit may set
the low noisy activation condition. This is because the activation
noise of the compressor affects the noise of the dryer most.
[0100] FIG. 13 shows that the activation time band of the
compressor is overlapped with a predetermined period of the low
noisy time band, if the dryer is activated.
[0101] In reference to FIG. 13, the activation of the compressor
starts at a time period which does not belong to the low noisy time
band (T3) and it enters into the low noisy time band (T3) after
that. This case may refer to `.alpha.`. In this case (.alpha.), the
compressor is activated at a first velocity (a normal velocity,
(Hz1) in a time band which does not belong to the low noisy time
band (T3) and it is activated at a second velocity (Hz2) reduced
from the first velocity in a time band which enters into the low
noisy time band (T3). Here, the activation of the compressor may
start at a time (t1) belonging to the low noisy time band (T3) and
it gets out of the low noisy time band (T3). This case may refer to
`.beta.`. In this case (.beta.), the compressor is activated at the
second velocity (Hz2) in a time belonging to the low noisy time
band (T3) and the velocity of the compressor is adjusted to be the
first velocity (the normal velocity, Hz1) in a time out of the low
noisy time band (T3).
[0102] In the meanwhile, after identifying the low noisy activation
condition of the dryer, the control unit may adjust the activation
velocity of the variable velocity type compressor based on the
identified activation condition (S1230).
[0103] The reason why the activation velocity of the compressor is
adjusted is that the noise and vibration generated by the
activation of the compressor has to be reduced. Because of that,
the control unit may control the noise and vibration by reducing
the activation velocity of the compressor. An activation velocity
of the compressor when the dryer is activated according to
`Standard course (or Normal course) in the day time may be defined
as `normal velocity (Hz1)`. When the low noisy activation condition
is set, the control unit may control the compressor to be activated
at an activation velocity (Hz2) which is lower than the normal
velocity. For example, the control unit may activate the compressor
at a predetermined rpm which is corresponding to approximately
40%.about.60% of a normal rpm.
[0104] When the low noisy activation condition is set, the control
unit may activate the compressor at a predetermined velocity
allowing the activation noise of the compressor to be a
predetermined db or less. For example, the control unit may adjust
the activation velocity of the compressor for the noise of the
compressor to be 40.about.60 db or less.
[0105] FIG. 14 is a graph illustrating noise distribution based on
the activation velocity of the compressor. A horizontal axis refers
to the activation velocity (hz) of the compressor and a vertical
axis refers to a noise (db) of the compressor.
[0106] In reference to FIG. 14, the noise of the compressor is
approximately 63 db, if the activation velocity of the compressor
is approximately 90 hz. When the activation velocity of the
compressor is lowered to be approximately 30 hz, the noise of the
compressor is approximately 48 db. For example, in case the low
noisy activation condition is not input by the user or it is not
input by the control unit automatically when the normal velocity
(Hz1) of the compressor is approximately 90 hz, the compressor may
be activated at the normal velocity.
[0107] If the low noisy activation condition is input by the user
or automatically input by the control unit, the compressor may be
activated at the second velocity (Hz2), for example, 30 hz, to
reduce the noise. In this case, the control unit may cut a
proportion of the activation velocity of the compressor to the
normal velocity to a predetermined percentage and it may activate
the compressor at the reduced velocity, as mentioned above.
Alternatively, the control unit may activate the compressor for the
noise of the compressor to be a predetermined value or less, as
mentioned above.
[0108] In the meanwhile, the dryer is embodied to explain the
embodiments and the control method according to the above
embodiments can be applied to the washing machine having a drying
function, by extension, even to the clothes treatment apparatus
including the heat pump to dry clothes.
[0109] Therefore, the control method according to the present
invention may prevent the liquid refrigerant from being drawn into
the compressor in the initial activation of the compressor. Because
of that, the compressor may be operated stably.
[0110] Furthermore, the control method according to the present
invention may control the quantity of the refrigerant based on the
temperature information relating to the compressor. Because of
that, the overheating of the compressor may be prevented.
[0111] Still further, the control method according to the present
invention may adjust the activation velocity of the variable
velocity type compressor. Because of that, the noise and vibration
generated in the compressor may be reduced remarkably.
[0112] It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the spirit or scope of the inventions. Thus,
it is intended that the present invention covers the modifications
and variations of this invention provided they come within the
scope of the appended claims and their equivalents.
* * * * *