U.S. patent application number 11/700816 was filed with the patent office on 2007-10-18 for variable capacity rotary compressor and method of varying capacity thereof.
This patent application is currently assigned to Samsung Electronics Co., Ltd.. Invention is credited to Sung Hea Cho, Kyung Jun Han, In Ju Lee, Jeong Bae Lee, Moon Joo Lee, Chang Joo Shin, Chun Mo Sung.
Application Number | 20070243079 11/700816 |
Document ID | / |
Family ID | 38605008 |
Filed Date | 2007-10-18 |
United States Patent
Application |
20070243079 |
Kind Code |
A1 |
Lee; Jeong Bae ; et
al. |
October 18, 2007 |
Variable capacity rotary compressor and method of varying capacity
thereof
Abstract
A variable capacity rotary compressor includes a housing having
a compressing chamber, a roller to rotate in the compressing
chamber while coming into contact with an inner peripheral surface
of the compressing chamber, a vane to move forward and rearward
along a guiding groove in accordance with rotation of the roller,
the guiding groove being formed in the housing in a radial
direction of the compressing chamber, a vane control device to
regulate restriction and release of the vane as to whether or not
the vane comes into continuous contact with an outer peripheral
surface of the roller, and a controller to output a control signal
to the vane control device for the variation of a compression
capacity, so as to regulate a proportion of restriction and release
of the vane, and a capacity variation method using the variable
capacity rotary compressor.
Inventors: |
Lee; Jeong Bae;
(Hwaseong-si, KR) ; Lee; Moon Joo; (Suwon-si,
KR) ; Lee; In Ju; (Yongin-si, KR) ; Cho; Sung
Hea; (Yongin-si, KR) ; Han; Kyung Jun;
(Incheon, KR) ; Sung; Chun Mo; (Hwaseong-si,
KR) ; Shin; Chang Joo; (Suwon-si, KR) |
Correspondence
Address: |
STANZIONE & KIM, LLP
919 18TH STREET, N.W., SUITE 440
WASHINGTON
DC
20006
US
|
Assignee: |
Samsung Electronics Co.,
Ltd.
Suwon-si
KR
|
Family ID: |
38605008 |
Appl. No.: |
11/700816 |
Filed: |
February 1, 2007 |
Current U.S.
Class: |
417/279 |
Current CPC
Class: |
F04C 18/3564 20130101;
F01C 21/0863 20130101; F04C 14/065 20130101; F04C 23/001 20130101;
F04C 23/008 20130101 |
Class at
Publication: |
417/279 |
International
Class: |
F04B 49/00 20060101
F04B049/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 12, 2006 |
KR |
2006-0033306 |
Claims
1. A variable capacity rotary compressor, comprising: a housing
having a compressing chamber; a roller to rotate in the compressing
chamber while contacting an inner peripheral surface of the
compressing chamber; a vane to move forward and rearward along a
guiding groove in accordance with the rotation of the roller, the
guiding groove being formed in the housing in a radial direction of
the compressing chamber; a vane control device to control whether
the vane comes into continuous contact with an outer peripheral
surface of the roller by regulating a restriction and a release of
the vane; and a controller to output a control signal to the vane
control device to regulate proportions of a restriction time and a
release time of the vane to vary a compression capacity of the
compressor.
2. The compressor according to claim 1, wherein: the guiding groove
comprises a hermetic chamber to receive a rear end of the vane; and
the vane control device regulates the restriction and the release
of the vane by regulating a pressure applied into the hermetic
chamber based on the control signal.
3. The compressor according to claim 2, wherein the vane control
device comprises: a high-pressure flow path to connect the hermetic
chamber to a discharge side of the compressor; a low-pressure flow
path to connect the hermetic chamber to a suction side of the
compressor; and a flow path selector to selectively connect the
hermetic chamber to the high-pressure flow path or low-pressure
flow path.
4. The compressor according to claim 3, wherein the flow path
selector is a 3-way valve to be switched by the control signal, and
the proportions of the restriction time and the release time of the
vane are regulated by modulating a pulse width of the control
signal to be applied to the 3-way valve.
5. A variable capacity rotary compressor, comprising: a housing
having a compressing chamber; a roller to rotate in the compressing
chamber while contacting an inner peripheral surface of the
compressing chamber; a vane to move forward and rearward along a
guiding groove in accordance with the rotation of the roller, the
guiding groove being formed in the housing in a radial direction of
the compressing chamber; a vane control device to control whether
the vane comes into continuous contact with an outer peripheral
surface of the roller by regulating a restriction and a release of
the vane; and a controller to output a control signal to the vane
control device to regulate a restriction time and a release time of
the vane during a preset time period to vary a compression capacity
of the compressor.
6. The compressor according to claim 5, wherein: each of the
restriction time and the release time of the vane is an integral
multiple of one-turn time of the compressor; and a sum of the
restriction time and the release time is a time corresponding to
one preset time period.
7. The compressor according to claim 5, wherein: the guiding groove
comprises a hermetic chamber to receive a rear end of the vane; and
the vane control device regulates the restriction time and the
release time of the vane by regulating a pressure to be applied
into the hermetic chamber based on the control signal.
8. The compressor according to claim 7, wherein the vane control
device comprises: a high-pressure flow path to connect the hermetic
chamber to a discharge side of the compressor; a low-pressure flow
path to connect the hermetic chamber to a suction side of the
compressor; and a flow path selector to selectively connect the
hermetic chamber to the high-pressure flow path or low-pressure
flow path.
9. The compressor according to claim 8, wherein the flow path
selector is a 3-way valve to be switched by the control signal, and
the restriction time and the release time of the vane are regulated
by modulating a pulse width of the control signal to be applied to
the 3-way valve.
10. The compressor according to claim 5, wherein the controller
performs a control operation such that the restriction time of the
vane decreases and the release time of the vane increases within
the one time period to increase a compression capacity.
11. A variable capacity rotary compressor, comprising: a housing
having first and second compressing chambers separated from each
other; first and second rollers to rotate in the first and second
compressing chambers, respectively, while respectively contacting
inner peripheral surfaces of the first and second compressing
chambers; first and second vanes to move forward and rearward along
first and second guiding grooves, respectively, in accordance with
the rotation of the first and second rollers, respectively, the
first and second guiding grooves being formed in the housing in a
radial direction of the first and second compressing chambers,
respectively; a first vane control device to regulate a restriction
time and a release time of the first vane using a pressure applied
to the first vane to control whether the first vane comes into
continuous contact with an outer peripheral surface of the first
roller; and a controller to output a control signal to the first
vane control device to regulate proportions of a restriction time
and a release time of the first vane to vary a compression capacity
of the compressor.
12. The compressor according to claim 11, wherein: the first
guiding groove comprises a first hermetic chamber to receive a rear
end of the first vane; and the pressure to be applied to the first
vane is regulated by the first vane control device based on the
control signal and applied into the first hermetic chamber.
13. The compressor according to claim 12, wherein the first vane
control device comprises: a first high-pressure flow path to
connect the first hermetic chamber to a discharge side of the
compressor; a first low-pressure flow path to connect the first
hermetic chamber to a suction side of the compressor; and a first
flow path selector to selectively connect the first hermetic
chamber to the first high-pressure flow path or first low-pressure
flow path.
14. The compressor according to claim 13, wherein the first flow
path selector is a 3-way valve to be switched by the control
signal, and the proportions of the restriction time and the release
time of the first vane are regulated by modulating a pulse width of
the control signal to be applied to the 3-way valve.
15. The compressor according to claim 11, wherein: the second
guiding groove comprises a second hermetic chamber to receive a
rear end of the second vane; and the compressor further comprises a
second vane control device to regulate a restriction time and a
release time of the second vane by regulating a pressure applied
into the second hermetic chamber based on the control signal.
16. The compressor according to claim 15, wherein the first and
second compressing chambers have different compression
capacities.
17. A method of varying a capacity of a variable capacity rotary
compressor having a housing having a compressing chamber, a roller
to rotate in the compressing chamber while contacting an inner
peripheral surface of the compressing chamber, and a vane to divide
an interior of the compressing chamber into a low-pressure section
and a high-pressure section and to move forward and rearward in a
radial direction of the compressing chamber in accordance with the
rotation of the roller, the method comprising: calculating an air
conditioning load depending on an operational state of an indoor
unit; and varying a compression capacity of the compressing chamber
to correspond to the calculated air conditioning load by regulating
proportions of a restriction time and a release time of the vane
based on the calculated air conditioning load.
18. The compressor according to claim 17, wherein: when the vane is
restricted, the vane does not come into continuous contact with an
outer peripheral surface of the roller; and when the restricted
vane is released, the vane comes into continuous contact with the
outer peripheral surface of the roller.
19. A variable capacity rotary compressor, comprising: a body to
form a compressing chamber having a roller therein; a vane moveably
disposed in the body to move between a forward position and a
rearward position; and a controller to generate a control signal to
control the vane according to a release time during which the vane
moves between the forward position and the rearward position and a
restriction time during which the vane remains in the rearward
position to vary a compression capacity of the compressing chamber
while maintaining a continuous operation of the compressor.
20. The compressor according to claim 19, further comprising: a
vane regulating device to regulate the movement of the vane by
releasing the vane from the rearward position and by restricting
the vane in the reward position, based on the generated control
signal.
21. The compressor according to claim 19, wherein the controller
generates the control signal to control the restriction time to
decrease and the release time to increase within a predetermined
compression time period to increase the compression capacity of the
compressing chamber while maintaining the continuous operation of
the compressor.
22. The compressor according to claim 19, wherein the controller
generates the control signal to control the restriction time to
increase and the release time to decrease within a predetermined
compression time period to decrease the compression capacity of the
compressing chamber while maintaining the continuous operation of
the compressor.
23. The compressor according to claim 19, further comprising: a
second compressing chamber; and a second vane disposed in the
compressing chamber to move to between a second forward position
and a second rearward position.
24. The compressor according to claim 23, wherein the controller
maintains a constant compression capacity of the second compressing
chamber.
25. The compressor according to claim 23, wherein the controller
generates a second control signal to control the second vane
according to a release time during which the second vane moves
between the second forward position and the second rearward
position and a restriction time during which the second vane
remains the second rearward position to vary a compression capacity
of the second compressing chamber while maintaining the continuous
operation of the compressor.
26. The compressor according to claim 19, further comprising: a
second vane regulating device to regulate the movement of the
second vane by releasing the second vane from the rearward position
and by restricting the second vane in the reward position, based on
the generated control signal.
27. The compressor according to claim 19, wherein the controller
controls the release time and the restriction time corresponding to
idling and compressing operations of the compressing chamber so
that the compressing capacity varies without stopping an operation
thereof.
28. A method of varying a compression capacity of a variable
capacity rotary compressor including a body to form a compressing
chamber having a roller therein and a vane moveably disposed in the
body to and move between a forward position and a rearward
position, the method comprising: controlling a release time during
which the vane moves between the forward positions and the rearward
position and a restriction time during which the vane remains in
the reward position to vary a compression capacity of the
compressing chamber while maintaining a continuous operation of the
compressor.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C.
.sctn.119(a) from Korean Patent Application No. 2006-0033306, filed
on Apr. 12, 2006 in the Korean Intellectual Property Office, the
disclosure of which is incorporated herein by reference in its
entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present general inventive concept relates to a variable
capacity rotary compressor and a method of varying a capacity
thereof, and, more particularly, to a variable capacity rotary
compressor in which a continuous capacity variation is possible
without stopping operation of the compressor via a regulation in a
proportion of a restriction time and/or a release time of a vane
provided in the rotary compressor, and a method of varying a
capacity of the compressor.
[0004] 2. Description of the Related Art
[0005] In general, variable capacity compressors have a compression
capacity that is variable according to a required load, and are
generally classified into a constant-speed compressor and a
variable-speed compressor.
[0006] A constant-speed compressor is a compressor that is normally
rotated at a constant speed, but can vary a capability thereof in
two stages by changing a rotating direction of the compressor from
forward to reverse or vice versa to achieve a variation in
compression capacity. An example of a constant-speed compressor is
disclosed in Korean Patent Publication No. 2004-0097746.
[0007] Korean Patent Publication No. 2004-0097746 describes a
rotary compressor including a cylinder having a predetermined size
of an inner volume, a roller rotating in the cylinder while
defining a fluid chamber with an inner peripheral surface of the
cylinder, and a plurality of suction ports arranged in the fluid
chamber to be spaced apart from one another by a predetermined
angle. The plurality of suction ports are selectively opened
according to a rotating direction of a drive shaft to allow a
compression capacity of the rotary compressor to vary in two stages
according to the rotating direction.
[0008] A variable-speed compressor is a compressor that is variable
in compression capacity via a regulation of revolutions per minute
of the compressor. The regulation of revolutions per minute is
achieved by an inverter, which is attached to a motor used to
rotate the compressor and adapted to regulate revolutions per
minute of the motor. An example of a variable-speed compressor is
disclosed in Korean Patent Publication No. 2001-0018242.
[0009] Korean Patent Publication No. 2001-0018242 describes a
compressor having an inverter, which detects indoor and outdoor
temperatures, calculates an entire load of the compressor and a
rotating frequency of an electric motor device by using a
temperature difference with a preset indoor temperature, a cooling
capacity of an indoor unit being operated, etc., and controls the
electric motor device based on the calculated rotating frequency,
thereby achieving a variation in the compression capacity of the
compressor.
[0010] In the case of the conventional constant-speed compressor as
stated above, to achieve a variation in capacity, the compressor
has to be stopped for a predetermined time to convert a forward
rotation into a reverse rotation or vice versa, and there is a
limit in that the capacity variation of the compressor is possible
only in two stages. To diversify a compression capacity, it is
necessary to bypass a part of a refrigerant to be discharged, which
has problems such as deterioration in operational efficiency and an
increase in manufacturing costs.
[0011] In the case of the conventional variable-speed compressor,
although continuous variation of a compression capacity is
possible, the variable-speed compressor requires a high-cost
inverter to regulate revolutions per minute of the compressor for
achieving the variation of a compression capacity, and therefore
has a problem of an increase in manufacturing costs.
SUMMARY OF THE INVENTION
[0012] The present general inventive concept provides a variable
capacity rotary compressor which can achieve a continuous capacity
variation using a low-cost control device having a simplified
configuration, and a capacity variation method using the variable
capacity rotary compressor.
[0013] The present general inventive concept also provides a
variable capacity rotary compressor to represent a highest
efficiency within an entire range of a variable compression
capacity, and a method of varying the capacity of the
compressor.
[0014] Additional aspects and advantages of the present general
inventive concept will be set forth in part in the description
which follows and, in part, will be obvious from the description,
or may be learned by practice of the general inventive concept.
[0015] The foregoing and/or other aspects and utilities of the
present general inventive concept may be achieved by providing a
variable capacity rotary compressor, including a housing having a
compressing chamber, a roller to rotate in the compressing chamber
while contacting an inner peripheral surface of the compressing
chamber, a vane to move forward and rearward along a guiding groove
in accordance with the rotation of the roller, the guiding groove
being formed in the housing in a radial direction of the
compressing chamber, a vane control device to control whether the
vane comes into continuous contact with an outer peripheral surface
of the roller by regulating a restriction and a release of the
vane, and a controller to output a control signal to the vane
control device to regulate proportions of a restriction time and a
release time of the vane to vary a compression capacity of the
compressor.
[0016] The guiding groove may include a hermetic chamber to receive
a rear end of the vane, and the vane control device may regulate
the restriction and the release of the vane by regulating a
pressure applied into the hermetic chamber based on the control
signal.
[0017] The vane control device may include a high-pressure flow
path to connect the hermetic chamber to a discharge side of the
compressor, a low-pressure flow path to connect the hermetic
chamber to a suction side of the compressor, and a flow path
selector to selectively connect the hermetic chamber to the
high-pressure flow path or low-pressure flow path.
[0018] The flow path selector may be a 3-way valve to be switched
by the control signal, and the proportions of the restriction time
and the release time of the vane may be regulated by modulating a
pulse width of the control signal to be applied to the 3-way
valve.
[0019] The foregoing and/or other aspects and utilities of the
present general inventive concept may also be achieved by providing
a variable capacity rotary compressor, including a housing having a
compressing chamber, a roller to rotate in the compressing chamber
contacting an inner peripheral surface of the compressing chamber,
a vane to move forward and rearward along a guiding groove in
accordance with the rotation of the roller, the guiding groove
being formed in the housing in a radial direction of the
compressing chamber, a vane control device to control whether the
vane comes into continuous contact with an outer peripheral surface
of the roller by regulating a restriction and a release of the
vane, and a controller to output a control signal to the vane
control device to regulate a restriction time and a release time of
the vane during a preset time period to vary a compression capacity
of the compressor.
[0020] Each of the restriction time and the release time of the
vane may be an integral multiple of one-turn time of the
compressor, and a sum of the restriction time and the release time
may be a time corresponding to one preset time period.
[0021] The guiding groove may include a hermetic chamber to receive
a rear end of the vane, and the vane control device may regulate
the restriction time and the release time of the vane by regulating
a pressure to be applied into the hermetic chamber based on the
control signal.
[0022] The vane control device may include a high-pressure flow
path to connect the hermetic chamber to a discharge side of the
compressor, a low-pressure flow path to connect the hermetic
chamber to a suction side of the compressor, and a flow path
selector to selectively connect the hermetic chamber to the
high-pressure flow path or low-pressure flow path.
[0023] The flow path selector may be a 3-way valve to be switched
by the control signal, and the restriction time and the release
time of the vane may be regulated by modulating a pulse width of
the control signal to be applied to the 3-way valve.
[0024] The controller may perform a control operation such that the
restriction time of the vane decreases and the release time of the
vane increases within the one time period, to increase a
compression capacity.
[0025] The foregoing and/or other aspects and utilities of the
present general inventive concept may also be achieved by providing
a variable capacity rotary compressor, including a housing having
first and second compressing chambers separated from each other,
first and second rollers to rotate in the first and second
compressing chambers, respectively, while contacting inner
peripheral surfaces of the first and second compressing chambers,
first and second vanes to move forward and rearward along first and
second guiding grooves, respectively, in accordance with the
rotation of the first and second rollers, respectively, the first
and second guiding grooves being formed in the housing in a radial
direction of the first and second compressing chambers,
respectively, a first vane control device to regulate a restriction
time and a release time of the first vane using a pressure applied
to the first vane to control whether the first vane comes into
continuous contact with an outer peripheral surface of the first
roller, and a controller to output a control signal to the first
vane control device to regulate proportions of a restriction time
and a release time of the first vane to vary a compression capacity
of the compressor.
[0026] The first guiding groove may include a first hermetic
chamber to receive a rear end of the first vane, and the pressure
to be applied to the first vane may be regulated by the first vane
control device based on the control signal and applied into the
first hermetic chamber.
[0027] The first vane control device may include a first
high-pressure flow path to connect the first hermetic chamber to a
discharge side of the compressor, a first low-pressure flow path to
connect the first hermetic chamber to a suction side of the
compressor, and a first flow path selector to selectively connect
the first hermetic chamber to the first high-pressure flow path or
first low-pressure flow path.
[0028] The first flow path selector may be a 3-way valve to be
switched by the control signal, and the proportions of the
restriction time and the release time of the first vane may be
regulated by modulating a pulse width of the control signal to be
applied to the 3-way valve.
[0029] The second guiding groove may include a second hermetic
chamber to receive a rear end of the second vane, and the
compressor may further include a second vane control device to
regulate a restriction time and a release time of the second vane
by regulating a pressure applied into the second hermetic chamber
based on the control signal.
[0030] The first and second compressing chambers may have different
compression capacities.
[0031] The foregoing and/or other aspects and utilities of the
present general inventive concept may also be achieved by providing
a method of varying a capacity of a variable capacity rotary
compressor having a housing having a compressing chamber, a roller
to rotate in the compressing chamber while contacting an inner
peripheral surface of the compressing chamber, and a vane to divide
an interior of the compressing chamber into a low-pressure section
and a high-pressure section and to move forward and rearward in a
radial direction of the compressing chamber in accordance with
rotation of the roller, the method including calculating an air
conditioning load depending on an operational state of an indoor
unit, and varying a compression capacity of the compressor chamber
to correspond to the calculated air conditioning load by regulating
proportions of a restriction time and a release time of the vane
based on the calculated air conditioning load.
[0032] When the vane is restricted, the vane may not come into
continuous contact with an outer peripheral surface of the roller,
and when the restricted vane ise released, the vane may come into
continuous contact with the outer peripheral surface of the
roller.
[0033] The foregoing and/or other aspects and utilities of the
present general inventive concept may also be achieved by providing
a variable capacity rotary compressor, including a body to form a
compressing chamber having a roller therein, a vane moveably
disposed in the body to move between a forward position and a
rearward position, and a controller to generate a control signal to
control the vane according to a release time during which the vane
moves between the forward position and the rearward position and a
restriction time during which the vane remains in the rearward
position to vary a compression capacity of the compressing chamber
while maintaining a continuous operation of the compressor.
[0034] The compressor may further include a vane regulating device
to regulate the movement of the vane by releasing the vane from the
rearward position and by restricting the vane in the reward
position, based on the generated control signal. The controller may
generate the control signal to control the restriction time to
decrease and the release time to increase within a predetermined
compression time period to increase the compression capacity of the
compressing chamber while maintaining the continuous operation of
the compressor. The controller may generate the control signal to
control the restriction time to increase and the release time to
decrease within a predetermined compression time period to decrease
the compression capacity of the compressing chamber while
maintaining the continuous operation of the compressor.
[0035] The compressor may further include a second compressing
chamber, and a second vane disposed in the compressing chamber to
move to between a second forward position and a second rearward
position. The controller may maintain a constant compression
capacity of the second compressing chamber. The controller may
generate a second control signal to control the second vane
according to a release time during which the second vane moves
between the second forward position and the second rearward
position and a restriction time during which the second vane
remains the second rearward position to vary a compression capacity
of the second compressing chamber while maintaining the continuous
operation of the compressor.
[0036] The compressor may further include a second vane regulating
device to regulate the movement of the second vane by releasing the
second vane from the rearward position and by restricting the
second vane in the reward position, based on the generated control
signal. The controller may control the release time and the
restriction time corresponding to idling and compressing operations
of the compressing chamber so that the compressing capacity varies
without stopping an operation thereof.
[0037] The foregoing and/or other aspects and utilities of the
present general inventive concept may also be achieved by providing
a method of varying a compression capacity of a variable capacity
rotary compressor including a body to form a compressing chamber
having a roller therein and a vane moveably disposed in the body to
and move between a forward position and a rearward position, the
method including controlling a release time during which the vane
moves between the forward positions and the rearward position and a
restriction time during which the vane remains in the reward
position to vary a compression capacity of the compressing chamber
while maintaining a continuous operation of the compressor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] These and/or other aspects and advantages of the present
general inventive concept will become apparent and more readily
appreciated from the following description of the embodiments,
taken in conjunction with the accompanying drawings of which:
[0039] FIG. 1 is a sectional view illustrating a variable capacity
rotary compressor, according to an embodiment of the present
general inventive concept;
[0040] FIG. 2 is a sectional view taken along the line II-II' of
FIG. 1;
[0041] FIGS. 3A and 3B are sectional views illustrating the
variable capacity rotary compressor of FIG. 1 in an idling rotation
state and compressing operation state in a first compressing
chamber, according to an embodiment of the present general
inventive concept;
[0042] FIG. 4 is a sectional view illustrating a variable capacity
rotary compressor, according to another embodiment of the present
general inventive concept;
[0043] FIG. 5 is a schematic control block diagram illustrating a
variable capacity rotary compressor, according to an embodiment of
the present general inventive concept;
[0044] FIG. 6 is a graph illustrating a control signal to be
applied to a vane control device of the variable capacity rotary
compressor of FIG. 1, according to an embodiment of the present
general inventive concept;
[0045] FIG. 7 is a table illustrating an example of a proportion of
a restriction time and a release time of a vane of the variable
capacity rotary compressor of FIG. 1, according to an embodiment of
the present general inventive concept;
[0046] FIG. 8 is a graph illustrating a relationship between an
efficiency and compression capacity of the variable capacity rotary
compressor of FIG. 4, according to an embodiment of the present
general inventive concept; and
[0047] FIG. 9 is a flow chart illustrating a method of varying a
capacity of a variable capacity rotary compressor, according to an
embodiment of the present general inventive concept.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0048] Reference will now be made in detail to the embodiments of
the present general inventive concept, examples of which are
illustrated in the accompanying drawings, wherein like reference
numerals refer to the like elements throughout. The embodiments are
described below in order to explain the present general inventive
concept by referring to the figures.
[0049] FIGS. 1, 2, 3A and 3B are views illustrating a variable
capacity rotary compressor, according to an embodiment of the
present general inventive concept. As illustrated in FIG. 1, the
rotary compressor of the present embodiment includes an electric
motor device 20 installed in an upper portion of a hermetic
container 10, and a compressing device 30 installed in a lower
portion of the hermetic container 10 and connected to the electric
motor device 20 through a rotating shaft 21.
[0050] The electric motor device 20 includes a cylindrical stator
22 secured to an inner surface of the hermetic container 10, and a
rotor 23 rotatably installed in the stator 22 and having a central
portion coupled to the rotating shaft 21. If power is applied to
the electric motor device 20, the rotor 23 rotates to drive the
compressing device 30 connected thereto through the rotating shaft
21.
[0051] The compressing device 30 includes a housing having an upper
first compressing chamber 31 and a lower second compressing chamber
32 separated from each other. The compressing device 30 further
includes first and second compressing units 40 and 50 provided in
the first and second compressing chambers 31 and 32, respectively,
and adapted to be operated by the rotating shaft 21.
[0052] The housing of the compressing device 30 includes an upper
first body 33 defining the first compressing chamber 31, a lower
second body 34 located below the first body 33 to define the second
compressing chamber 32, an intermediate plate 35 located between
the first and second bodies 33 and 34 to separate the first and
second compressing chambers 31 and 32 from each other, and first
and second flanges 36 and 37 configured to close an upper-side
opening of the first compressing chamber 31 and a lower-side
opening of the second compressing chamber 32, respectively. The
first and second flanges 36 and 37 are mounted to a top of the
first body 33 and a bottom of the second body 34, respectively, to
support the rotating shaft 21 together. The rotating shaft 21 is
installed to penetrate the center of both the first and second
compressing chambers 31 and 32 and to connect to the first and
second compressing units 40 and 50 inside the first and second
compressing chambers 31 and 32.
[0053] The first and second compressing units 40 and 50 include
first and second eccentric portions 41 and 51 located around the
rotating shaft 21 inside the first and second compressing chambers
31 and 32, and first and second rollers 42 and 52 rotatably coupled
to outer peripheral surfaces of the first and second eccentric
portions 41 and 51, respectively, to rotate in contact with inner
peripheral surfaces of the first and second compressing chambers 31
and 32. The first eccentric portion 41 and second eccentric portion
51 are arranged in opposite eccentric directions with respect to
the rotational shaft 21 to maintain a balance therebetween.
[0054] The first and second compressing units 40 and 50 further
include first and second vanes 43 and 53, respectively. The first
and second vanes 43 and 53 serve to divide the first and second
compressing chambers 31 and 32 as they perform forward and rearward
movements in a radial direction of the first and second compressing
chambers 31 and 32 according to rotations of the first and second
rollers 42 and 52. The first and second vanes 43 and 53, as
illustrated in FIGS. 1 and 2, are received in first and second vane
guiding grooves 44 and 54 that extend lengthwise in the radial
direction of the first and second compressing chambers 31 and 32,
such that forward and rearward movements of the first and second
vanes 43 and 53 are guided by the first and second vane guiding
grooves 44 and 54, respectively. A vane spring 55 is installed in
the second vane guiding groove 54 and adapted to pressure the
second vane 53 toward the second roller 52 to allow the second vane
53 to divide the second compressing chamber 32.
[0055] As illustrated in FIG. 2, a first hermetic chamber 46 is
formed at a rear side of the first vane guiding groove 44 and
adapted to receive a rear end of the first vane 43. The first
hermetic chamber 46 is separated from an inner space of the
hermetic container 10 by the intermediate plate 35 and the first
flange 36. The first hermetic chamber 46 is able to receive a
predetermined amount of gas, and is defined by a cylindrical
expanded portion 46a having a diameter larger than a width of the
first vane 43. The rear end of the first vane 43 may be formed with
a curved surface 43a to reduce a generation of noise when the rear
end of the first vane 43 collides with the cylindrical expanded
portion 46a of the first hermetic chamber 46 during a rearward
movement of the first vane 43. To enhance the noise reduction
effect, a vibration absorbing member (not illustrated) may be
mounted at a collision position of the rear end of the first vane
43 or cylindrical expanded portion 46a.
[0056] In the present embodiment, a first vane control device 60 is
provided to apply a suction pressure into the first hermetic
chamber 46 to restrict the first vane 43 in a rearwardly moved
state, or to apply a discharge pressure into the first hermetic
chamber 46 to release the restricted first vane 43, thereby
allowing forward and rearward movements of the first vane 43. By
apply the suction pressure into the first hermetic chamber 46 to
restrict the first vane 43 and applying the discharge pressure into
the first hermetic chamber 46 to release the restricted first vane
43, the first vane control device 60 causes a compressing operation
or idling rotation in the first compressing chamber 31, thereby
enabling a variation in compression capacity. The detailed
configuration and operation of the first vane control device 60 is
described below.
[0057] The first and second bodies 33 and 34 have suction holes 73
connected to suction pipes 71 and 72 to introduce gas into the
first and second compressing chambers 31 and 32, and discharge
holes 75 and 76 (see FIG. 1), respectively, to discharge the gas,
which was compressed in the respective first and second compressing
chambers 31 and 32, into the hermetic container 10. If the
compressor operates, the interior of the hermetic container 10 is
kept at a high pressure by the compressed gas discharged through
the discharge holes 75 and 76. The compressed gas inside the
hermetic container 10 is guided to an outside through a discharge
pipe 77 (see FIG. 1) that is located on a top of the hermetic
container 10. Here, the gas to be suctioned first passes through an
accumulator 78, prior to being guided to the suction holes 73 of
the respective compressing chambers 31 and 32 through the suction
pipes 71 and 72.
[0058] The vane control device 60, as illustrated in FIG. 1,
includes a first connecting pipe 61 directly connected to the first
hermetic chamber 46 at the rear side of the first vane guiding
groove 44, a first high-pressure pipe 62 connecting the first
connecting pipe 61 to the discharge pipe 77, a first low-pressure
pipe 63 connecting the first connecting pipe 61 to a suction pipe
70, and a first flow path selector 64 to selectively communicate
the first connecting pipe 61 with the first high-pressure pipe 62
or first low-pressure pipe 63. A flow path extended through the
first high-pressure pipe 62, the first flow path selector 64, and
the first connecting pipe 61 defines a high-pressure flow path to
the a discharge pressure into the first hermetic chamber 46. Also,
a flow path extended through the first low-pressure pipe 63, the
first flow path selector 64, and the first connecting pipe 61
defines a low-pressure flow path to transmit the suction pressure
into the first hermetic chamber 46. The first flow path selector 64
is installed at a position where the first connecting pipe 61, the
first high-pressure pipe 62, and the first low-pressure pipe 63 are
connected to one another, and an example thereof may include an
electrically-operated 3-way valve. The first connecting pipe 61 has
an exit connected to the first flange 36, and the first flange 36
has a communication path 36a to directly communicate the first
connecting pipe 61 with the first hermetic chamber 46. In another
example, the first connecting pipe 61 of the first vane control
device 60 may be connected to the intermediate plate 35, and the
intermediate plate 35 may have a communication path communicating
with the first hermetic chamber 46.
[0059] Now, an operation of the first vane control device 60 will
be described.
[0060] As illustrated in FIGS. 1 and 2, when the first flow path
selector 64 operates to communicate the first high-pressure pipe 62
to the first connecting pipe 61, the discharge pressure is applied
to the first hermetic chamber 46.
[0061] Accordingly, the first vane 43 is pushed toward the first
compressing chamber 31 by the discharge pressure, thus causing the
first vane 43 to perform forward and rearward movements in
accordance with eccentric rotation of the first roller 42 as
illustrated in FIG. 3. On the other hand, when the first flow path
selector 64 operates to communicate the first low-pressure pipe 63
to the first connecting pipe 61, the suction pressure is applied to
the first hermetic chamber 46. In this case, as illustrated in FIG.
3A, the first vane 43 is stopped at its rearwardly moved state,
thus causing an idling rotation in the first compressing chamber 31
(referred to as a "restriction state"). Specifically, if the
suction pressure is applied to the first hermetic chamber 46, a
pressure in the first compressing chamber 31 is changed to be
larger than or equal to a pressure in the first hermetic chamber
46. This is because a slight compressing operation is caused in the
first compressing chamber 31 by eccentric rotation of the first
roller 42 in addition to the suction pressure applied to the first
compressing chamber 31.
[0062] When the first compressing chamber 31 and first hermetic
chamber 46 are in a pressurized state according to the suction
pressure, the first vane 43 is moved rearward in accordance with
eccentric rotation of the first roller 42, and is restricted so as
not to be moved forward. As a result, a division of refrigerant
suction and discharge sections in the first compressing chamber 31
disappears, resulting in a refrigerant being introduced into the
first compressing chamber 31 to circulate only along the first
compressing chamber 31 with no substantial compression stroke
(idling operation). In FIG. 3A, an arrow illustrated in the first
vane 43 represents a force applied to the first vane 43 by a
pressure difference, and an arrow illustrated in the first
connecting pipe 61 represents a variation in the pressure of the
refrigerant that is caused as the first connecting pipe 61 is
disconnected from the first high-pressure pipe 62 to communicate
with the first low-pressure pipe 62.
[0063] Conversely, if the discharge pressure is applied to the
first hermetic chamber 46, a pressure in the first hermetic chamber
46 is changed to be larger than that of the first compressing
chamber 31, thus causing the first vane 43 to move forward and
rearward in accordance with eccentric rotation of the first roller
42 to achieve a compressing operation in the first compressing
chamber 31 (referred to as a "restriction release state"), that is,
compressing operation.
[0064] In the present embodiment, as stated above, the operation of
the first vane 43 is selectively restricted under a control of the
first vane control device 60 to cause a compressing operation or an
idling rotation in the first compressing chamber 31, thereby
enabling a variation in compression capacity. Specifically, if a
digital control signal is applied to the first flow path selector
64 to regulate a proportion of a restriction time and/or a release
time of the first vane 43, a compression capacity of the first
compressing chamber 31 is variable from 0% to 100% based on a total
compression capacity. The variation of the compression capacity is
described below with reference to FIGS. 6 and 7.
[0065] FIG. 7 is a table illustrating a control example of a a of
restriction time and a release time of a vane of the variation of a
compression capacity of FIG. 1 according to a required load,
according to an embodiment of the present general inventive
concept. The table of FIG. 7 was obtained under the following
conditions: a capacity varying period was 20 sec., two compressing
chambers having different compression capacities were prepared,
only one of the compressing chambers being provided with a vane
control device, and a capacity ratio of one compressing chamber
(having the vane control device) to the other compressing chamber
(having no vane control device) was 7:3.
[0066] Referring to FIGS. 1-3B and 7, a compression capacity of the
upper first compressing chamber 31 may vary at predetermined time
periods, and each time period may be a sum of a time T_f required
to release the first vane 43 and a time T_p required to restrict
the first vane 43. In FIG. 7, each predetermined period is set up
to 20 sec. Where a compression capacity of the upper first
compressing chamber 31 varies at predetermined time periods (each
period is the sum of a time T_f required to release the first vane
43 and a time T_p required to restrict the first vane 43, In FIG.
7, each period being set up to 20 sec.), the compression capacity
of the upper first compressing chamber 31 can vary by regulating
the times T_f and T_p, thus enabling a variation in a total
compression capacity.
[0067] Here, the compression capacity of the upper first
compressing chamber 31 is calculated in consideration of the second
compressing chamber 32 performing a compressing operation
continuously. For example, to guarantee a capacity up to 50%, the
upper first compressing chamber 31 charges 20% of the total
capacity except for the compression capacity of the lower second
compressing chamber 32. In this case, the time T_f that is a time
required to perform a compressing operation in the upper first
compressing chamber 31 should be regulated to occupy a proportion
of approximately 6/20 (which corresponds to a time required to
release the first vane 43 of 6 sec.) of the predetermined time
period 20. Such a proportion regulation is necessary where a load
is larger than 30%, but smaller than 100%, and can be performed
simply by modulating a pulse width of a digital control signal to
be applied to the first flow path selector 64. An example of the
control signal in the case of a load between 30% and 100% is
illustrated in FIG. 6 in a region designated as "intermediate
load".
[0068] The above mentioned predetermined time period can be
appropriately set up as desired by a user. The shorter the
predetermined time period, the more rapidly a response dealing with
a load variation can be performed, but this has a problem of
excessive noise, etc. On the other hand, the longer the
predetermined time period, the slower the response dealing with a
load variation, but this has an advantage such as a reduction in
noise, etc.
[0069] The phrase "full load only" of FIG. 6 refers to a state in
which both of the upper first and lower second compressing chambers
31 and 32 perform a compressing operation as a result of applying
the discharge pressure into the first hermetic chamber 46 to cause
forward and rearward movements of the first vane 43. In the "full
load only" state, only a control signal corresponding to a value of
"full" is applied to the first flow path selector 64. On the other
hand, the phrase "part load only" of FIG. 6 refers to a state in
which the upper first compressing chamber 31 performs an idling
rotation as a result of applying the suction pressure into the
first hermetic chamber 46 to restrict the first vane 43 and only
the lower second compressing chamber 32 performs a compressing
operation. In the "part load only" state, only a control signal
corresponding to a value of "part" is applied to the first flow
path selector 64. When the control signal related to the value of
"full" is applied, the first flow path selector 64 connects the
first connecting pipe 61 to the first high-pressure pipe 62,
whereas, when the control signal related to the value of "part" is
applied, the first flow path selector 64 connects the first
connecting pipe 61 to the first low-pressure pipe 63.
[0070] In the rotary compressor consistent with the present
embodiment, as stated above, the lower second compressing chamber
32 performs a compressing operation continuously. Therefore, a
capacity variation range departs from the compression capacity of
the lower second compressing chamber 32, and the rotary compressor
realizes a partial capacity variation.
[0071] FIG. 4 is a sectional view illustrating a variable capacity
rotary compressor, according to another embodiment of the present
general inventive concept. The compressor of the present embodiment
may include a second vane control device 80 to control a
restriction of the second vane 53 as well as the first vane control
device 60. In the compressor of the present embodiment,
accordingly, a second hermetic chamber 56 is defined at a rear side
of the second vane guiding groove 54. The second vane control
device 80 includes a second connecting pipe 81 connected to the
second flange 37 to directly communicate with the second hermetic
chamber 56, a second high-pressure pipe 82 extending from the first
high-pressure pipe 62 to be connected to the second connecting pipe
81, a second low-pressure pipe 83 extending from the first
low-pressure pipe 63 to be connected to the second connecting pipe
81, and a second flow path selector 84 to selectively communicate
the second connecting pipe 81 with the second high-pressure pipe 82
or with second low-pressure pipe 83. An operation principle of the
second vane control device 80 is the same as or similar to that of
the first vane control device 60.
[0072] Differently from the previous embodiment illustrated in
FIGS. 1-3B, the rotary compressor of the present embodiment can
realize a capacity variation even in the lower second compressing
chamber 32, and thus a capacity variation thereof of the lower
second compressing chamber 32 in the present embodiment can be
within a range from 0% to 100% of a maximum capacity of the
compressor. However, in this case, there is a more complicated
structure and increased manufacturing costs as compared to the
previous embodiment. As will be appreciated, of course, in the case
where a compressor having a single compressing chamber is provided
with a vane control device to control a vane, a capacity variation
is possible within the entire range from 0% to 100%.
[0073] FIG. 8 is a graph illustrating a relationship between an
efficiency and compression capacity of the variable capacity rotary
compressor of FIG. 4, according to an embodiment of the present
general inventive concept. As can be understood from the dashed
line of FIG. 8 representing an efficiency of a conventional
constant-speed compressor, the efficiency of the conventional
compressor is high in the case where a second-stage compression
capacity coincides with an air conditioning load. However, at
points A and B where the compression capacity does not coincide
with the air conditioning load, a part of the refrigerant being
discharged has to be bypassed to forcibly fulfill a required load,
resulting in deterioration in efficiency. On the other hand, in the
rotary compressor consistent with the present embodiment ("novel
compressor" in FIG. 8), as a result of regulating proportions of a
restriction time and a release time of the first and second vanes
43 and 53 using the first and second vane control devices 60 and
80, a high efficiency can be realized without a bypass of the
refrigerant required to forcibly raise the compression capacities
at the points A and B. Also, the conventional constant-speed
compressor should be stopped for a predetermined time required to
vary a compression capacity, but the rotary compressor of the
present embodiment can achieve a variation in compression capacity
without being stopped, and thus is more efficient than the
conventional compressor.
[0074] Hereinafter, a method of varying a capacity of a compressor,
according to an embodiment of the present general inventive
concept, will be described with reference to FIGS. 5 and 9.
[0075] Assuming a multi-type air conditioner having a plurality of
indoor units 401a to 401d, a controller 410 calculates a desired
total air conditioning load using an operational state of the
plurality of indoor units 401a to 401d, a temperature difference
between a preset temperature and each indoor temperature, a cooling
capacity of each indoor unit, etc. and operation S910. Then, the
controller 410 calculates a compression capacity of a compressor
450 corresponding to the calculated total air conditioning load at
operation S920. Specifically, with reference to FIGS. 1-3B, in
consideration of the fact that the lower second compressing chamber
32 is continuously kept in a pressurized state, a compression
capacity to be achieved in the upper first compressing chamber 31
is calculated (operation S920). Moreover, referring to FIG. 4,
since both the upper first and the lower second compressing
chambers 31 and 32 can realize a capacity variation, a compression
capacity to be achieved in each of the upper first and the lower
second compressing chambers 31 and 32 is calculated in
consideration of the compression capacities of the upper first and
lower second compressing chambers 31 and 32 and a total compression
capacity (operation S920).
[0076] Based on the calculated compression capacity of each
compressing chamber, a proportion of a restriction time and/or a
release time of a vane (e.g., the first vane 43 and or second vane
53 illustrated in FIGS. 1 and 4) is determined at operation S930.
It will be appreciated that a more efficient variation in
compression capacity can be achieved if the proportion of the
restriction time and the release time of the vane is preset in
consideration of a control time period and stored as a table. The
controller 410 applies control signals, which correspond to the
preset proportions of the restriction time and the release time of
the vanes, to a vane control device (e.g., the vane control devices
60 and 80 illustrated in FIGS. 1 and 4), to enable a variation in
compression capacity. As a result of performing the restriction and
release of the vane (e.g., the vanes 43 and 53) based on the preset
proportions upon receiving the control signals applied thereto, a
required compression stroke and idling rotation are repeated by a
predetermined rate, resulting in a compression capacity
corresponding to the air conditioning load (step S940).
[0077] As apparent from the above description, a variable capacity
rotary compressor according to embodiments of the present general
inventive concept enables a continuous variation in compression
capacity with low costs.
[0078] Further, a variable capacity rotary compressor according to
embodiments of the present general inventive concept enables a
compressing operation with a highest efficiency within an entire
range of a variable capacity.
[0079] Furthermore, a variable capacity rotary compressor according
to embodiments of the present general inventive concept enables a
continuous variation in capacity without performing stopping
operation of the compressor.
[0080] Although a few embodiments of the present general inventive
concept have been shown and described, it will be appreciated by
those skilled in the art that changes may be made in these
embodiments without departing from the principles and spirit of the
general inventive concept, the scope of which is defined in the
appended claims and their equivalents.
* * * * *