U.S. patent application number 12/847603 was filed with the patent office on 2011-05-26 for heat pump type cooling/heating apparatus.
Invention is credited to Sim Won Chin, Bum Suk Kim, Eung Yul Lee, Sang Kyoung Park.
Application Number | 20110120179 12/847603 |
Document ID | / |
Family ID | 43768889 |
Filed Date | 2011-05-26 |
United States Patent
Application |
20110120179 |
Kind Code |
A1 |
Chin; Sim Won ; et
al. |
May 26, 2011 |
HEAT PUMP TYPE COOLING/HEATING APPARATUS
Abstract
A heat pump type cooling/heating apparatus comprises a coolant
injection path and a gaseous coolant adjustment valve. The coolant
injection path may be split between a cascade heat exchanger and an
evaporator of a low-temperature refrigeration cycle to inject
coolant into a low pressure side compressor, or between a water
coolant heat exchanger and cascade heat exchanger to inject coolant
into a high pressure side compressor of a high temperature
refrigeration cycle. The gaseous coolant adjustment valve may be
provided in the coolant injection path and is adjusted to
correspond to a load of a
Inventors: |
Chin; Sim Won; (Changwon-si,
KR) ; Lee; Eung Yul; (Changwon-si, KR) ; Kim;
Bum Suk; (Changwon-si, KR) ; Park; Sang Kyoung;
(Changwon-si, KR) |
Family ID: |
43768889 |
Appl. No.: |
12/847603 |
Filed: |
July 30, 2010 |
Current U.S.
Class: |
62/510 ; 62/512;
62/513 |
Current CPC
Class: |
F25B 2700/21161
20130101; F24D 17/02 20130101; Y02B 30/52 20130101; F25B 2400/13
20130101; F25B 1/10 20130101; Y02B 30/12 20130101; F25B 7/00
20130101; F24D 3/18 20130101; F24D 19/1072 20130101; F25B 2339/047
20130101; F25B 2400/23 20130101; F25B 2600/2509 20130101; F25B
41/39 20210101; F24D 3/08 20130101; F24D 2200/24 20130101 |
Class at
Publication: |
62/510 ; 62/512;
62/513 |
International
Class: |
F25B 1/10 20060101
F25B001/10; F25B 43/00 20060101 F25B043/00; F25B 41/00 20060101
F25B041/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 20, 2009 |
KR |
10-2009-0112740 |
Claims
1. A heat pump type cooling/heating apparatus comprising: a cascade
cycle unit that includes a cascade heat exchanger that performs a
heat exchange between a first coolant of a low temperature
refrigeration cycle and a second coolant of a high temperature
refrigeration cycle, and a water coolant heat exchanger that heats
water while the second coolant of the high temperature
refrigeration cycle is condensed, wherein the water coolant heat
exchanger is coupled to a destination via a water circulation path,
the heat pump type cooling/heating apparatus further comprising: a
coolant injection path that is split between the cascade heat
exchanger and an evaporator of the low temperature refrigeration
cycle to inject a coolant into a low pressure side compressor of
the low temperature refrigeration cycle, or split between the water
coolant heat exchanger and the cascade heat exchanger to inject a
coolant into a high pressure side compressor of the high
temperature refrigeration cycle; and a gaseous coolant adjustment
valve provided in the coolant injection path and adjusted
corresponding to a load of the destination.
2. The apparatus of claim 1, further comprising: a gas/liquid
separator to separate a coolant condensed in the cascade heat
exchanger into a liquid coolant and a gaseous coolant; and an
auxiliary expansion mechanism, provided between the cascade heat
exchanger and the gas/liquid separator, to expand a coolant.
3. The apparatus of claim 2, wherein: the low temperature
refrigeration cycle forms a closed path running from a low pressure
side compressor through the cascade heat exchanger and a first
expansion mechanism to an evaporator, the high temperature
refrigeration cycle forms a closed path running from a high
pressure side compressor through the water coolant heat exchanger
and a second expansion mechanism to the cascade heat exchanger, and
the gas/liquid separator is provided between the cascade heat
exchanger and the first expansion mechanism.
4. The apparatus of claim 3, wherein the low pressure side
compressor, the cascade heat exchanger, the first expansion
mechanism, the evaporator, the high pressure side compressor, the
second expansion mechanism, the water coolant heat exchanger, the
coolant injection path, the gaseous coolant adjustment valve, the
gas/liquid separator, and the auxiliary expansion mechanism are
installed in a single unit.
5. The apparatus of claim 3, wherein: the low pressure compressor,
first expansion mechanism, and evaporator are installed in an
outdoor unit, the cascade heat exchanger, high pressure side
compressor, second expansion mechanism, and water coolant heat
exchanger are installed in a cascade unit, and the coolant
injection path, gaseous coolant adjustment valve, gas/liquid
separator, and auxiliary expansion mechanism are installed in one
of the outdoor unit or the cascade unit.
6. The apparatus of claim 1, further comprising: a gas/liquid
separator to separate a coolant condensed in the water coolant heat
exchanger into a liquid coolant and a gaseous coolant; and an
auxiliary expansion mechanism, provided between the water coolant
heat exchanger and the gas/liquid separator, to expand a
coolant.
7. The apparatus of claim 6, wherein: the low temperature
refrigeration cycle forms a closed path running from a low pressure
side compressor through the cascade heat exchanger and a first
expansion mechanism to an evaporator, the high temperature
refrigeration cycle forms a closed path running from a high
pressure side compressor through the water coolant heat exchanger
and a second expansion mechanism to the cascade heat exchanger, and
the gas/liquid separator is provided between the water coolant heat
exchanger and the second expansion mechanism.
8. The apparatus of claim 7, wherein: the low pressure side
compressor, cascade heat exchanger, first expansion mechanism,
evaporator, high pressure side compressor, second expansion
mechanism, water coolant heat exchanger, coolant injection path,
gaseous coolant adjustment valve, gas/liquid separator, and
auxiliary expansion mechanism are installed in a single unit.
9. The apparatus of claim 7, wherein: the low pressure compressor,
first expansion mechanism, and evaporator are installed in an
outdoor unit, the cascade heat exchanger, high pressure side
compressor, second expansion mechanism, and water coolant heat
exchanger are installed in a cascade unit, and the coolant
injection path, gaseous coolant adjustment valve, gas/liquid
separator, and auxiliary expansion mechanism are installed in one
of the outdoor unit or the cascade unit.
10. The apparatus of claim 9, wherein the cascade unit is
integrally mounted on the outdoor unit.
11. The apparatus of claim 9, wherein the cascade unit is separated
from the outdoor unit.
12. The apparatus of claim 1, further comprising: a load sensor to
sense the load of the destination; and a controller to control the
gaseous coolant adjust valve according to a sensing result of the
load sensor.
13. The apparatus of claim 12, wherein the load sensor is provided
over the water circulation path.
14. The apparatus of claim 13, wherein the controller opens the
gaseous coolant adjustment valve when a temperature sensed by the
load sensor is less than a predetermined valve, and closes the
gaseous coolant adjustment valve when a temperature sensed by the
load sensor is more than the predetermined valve.
15. The apparatus of claim 1, wherein the destination includes a
room heating unit coupled to the water circulation path and a water
heating unit connected to the water circulation path.
16. The apparatus of claim 1, wherein at least one of the low
pressure side compressor or the high pressure compressor, which is
coupled to the coolant injection path, is configured as a two-stage
compressor.
17. The apparatus of claim 1, wherein at least one of the low
pressure side compressor or the high pressure compressor, which is
coupled to the coolant injection path, is configured as a screw
compressor.
18. The apparatus of claim 1, wherein at least one of the low
pressure side compressor or the high pressure compressor, which is
coupled to the coolant injection path, is configured as a scroll
compressor.
19. The apparatus of claim 1, wherein at least one of the low
pressure side compressor or the high pressure compressor, which is
coupled to the coolant injection path, is configured as a twin
rotary compressor.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority under 35 U.S.C.
.sctn.119 to Korean Patent Application No. 10-2009-0112740, filed
on Nov. 20, 2009 in Korea, the entirety of which is hereby
incorporated by reference.
BACKGROUND
[0002] 1. Field
[0003] One or more embodiments described herein relate to thermal
control.
[0004] 2. Background
[0005] Heat pumps are in widespread use for heating and cooling
homes. However, they have drawbacks. For example, heat pumps fail
to provide sufficient cooling/heating performance for many homes or
buildings, especially those of larger size. Also, operational
efficiency is compromised because of the need to perform frequent
defrosting operations for the evaporator.
BRIEF DESCRIPTION OF THE DRAWING
[0006] FIG. 1 is a diagram of one embodiment of a cooling/heating
apparatus.
[0007] FIG. 2 is a block diagram of the cooling/heating apparatus
of FIG. 1.
[0008] FIG. 3 is a diagram of one type of cascade cycle unit for
use in FIG. 1.
[0009] FIG. 4 is a graph of a P-H relationship obtained for a
cooling/heating apparatus according to one or more of the
embodiments herein.
[0010] FIG. 5 is a diagram of another embodiment of a
cooling/heating apparatus.
[0011] FIG. 6 is a diagram of another embodiment of a
cooling/heating apparatus.
[0012] FIG. 7 is a diagram showing a manner in which a cascade unit
and outdoor unit may be separately provided in the apparatus of
FIG. 6.
[0013] FIG. 8 is a diagram showing a manner in which the outdoor
unit may be attached to the cascade unit in the apparatus of FIG.
6.
DETAILED DESCRIPTION
[0014] FIG. 1 shows a first embodiment of a heat pump type
cooling/heating apparatus which includes a refrigeration cycle
apparatus 3 that heats water using a coolant, circulates the heated
water, and supplies the heated water to destinations 1 and 2
requiring hot water.
[0015] Destinations 1 and 2 include a room heating unit 1 that
heats a room using the water heated by the coolant and a water
heating unit 2 that discharges the heated water to the outside
through a discharging device, such as a shower head. The room
heating unit and the water heating unit will be described in
greater detail below.
[0016] The refrigeration cycle apparatus 3 may include a cascade
cycle unit 4 and a gas injection mechanism 5.
[0017] The cascade cycle unit 4 may include a cascade heat
exchanger that performs a heat exchange between a first coolant of
a low temperature refrigeration cycle A and a second coolant of a
high temperature refrigeration cycle B, and a water coolant heat
exchanger in which the second coolant of the high temperature
refrigeration cycle B is condensed while heating water.
[0018] The first and second coolants have different condensation
temperature and evaporation temperature. For example, in a case
where theist coolant has a low condensation temperature and
evaporation temperature of R410A, the second coolant may have a
higher condensation temperature and evaporation temperature of
R134a than the first coolant.
[0019] The gas injection mechanism 5 expands the coolant condensed
in one of the low temperature refrigeration cycle A and the high
temperature refrigeration cycle B, separates a gaseous coolant from
the condensed coolant, and then injects the separated gaseous
coolant into a compressor in the refrigeration cycle in which the
gas injection mechanism is provided. The gas injection mechanism
may be included in at least one of the low temperature
refrigeration cycle A and the high temperature refrigeration cycle
B.
[0020] The low temperature refrigeration cycle A, the high
temperature refrigeration cycle B, and the gas injection mechanism
will now be described in greater detail with the assumption that
the gas injection mechanism is provided in the low temperature
refrigeration cycle A.
[0021] The low temperature refrigeration cycle A forms a closed
path running from a low pressure side compressor 6 through a
cascade heat exchanger 10 and a first expansion mechanism 12 to an
evaporator 14. The first coolant is compressed in the low pressure
side compressor 6, condensed in the cascade heat exchanger 10,
expanded in the first expansion mechanism 12, and evaporated in the
evaporator 14. The second coolant may be evaporated while the first
coolant repeats the compression, condensation, expansion, and
evaporation.
[0022] The low pressure side compressor 6, which compresses the
first coolant, is connected to the cascade heat exchanger 10 and a
low pressure side compressor discharge pipe 7. The low pressure
side compressor 6 may be connected to the evaporator 14 and a low
pressure side compressor suction pipe 8.
[0023] The low pressure side compressor may be configured as a two
stage compressor, a twin rotary compressor, a screw compressor, or
a scroll compressor, so that the gaseous coolant is gas injected to
low pressure side compressor 6 in a case where gas injection
mechanism 5 is provided in the low temperature refrigeration cycle
A.
[0024] A two stage compressor, which is connected in series with a
coolant path, includes a first compression part and a second
compression part. A coolant is first condensed in the first
compression part and then re-condensed in the second compression
part. The coolant evaporated in evaporator 14 is sucked and
compressed in the first compression part before discharge.
[0025] The gas injection mechanism 5 is connected to a connection
path between the first compression part and second compression
part. The gaseous coolant injected from the gas injection mechanism
is mixed with the coolant that is compressed and discharged by the
first compression part, and then the mixed material may be
compressed and discharged by the second compression part.
[0026] A twin rotary compressor includes first and second
compression parts that perform compression by the same motor. The
coolant evaporated in the evaporator 14 is sucked, compressed, and
discharged by the first compression part. The gas injection
mechanism 5 is connected to the second compression part. The
coolant evaporated in the evaporator 14 is compressed and
discharged by the first compression part. The gaseous coolant
injected by the gas injection mechanism may be compressed and
discharged by the second compression part.
[0027] A screw compressor is a rotary displacement compressor that
includes a pair of male and female screw rotors engaged with each
other, with a gaseous coolant compressed between the male and
female screw rotors. The coolant evaporated in evaporator 14 is
sucked and compressed in a compression chamber of the
compressor.
[0028] The gas injection mechanism is connected to an injection
port communicating with one side of the compression chamber of the
screw compressor. The gaseous coolant injected from the gas
injection mechanism may be mixed with the coolant compressed in the
screw compressor and the resultant material may be compressed and
discharged.
[0029] A scroll compressor compresses a coolant by rotating a
rotational scroll in a compression chamber. The coolant evaporated
in evaporator 14 is sucked and compressed in the compression
chamber of the scroll compressor. The gas injection mechanism is
connected to an injection port communicating with one side of the
compression chamber of the scroll compressor. The gaseous coolant
injected from the gas injection mechanism is mixed with the coolant
condensed in the scroll compressor, and the resultant material may
be compressed and discharged.
[0030] The cascade heat exchanger 10 includes a condensation path
to condense the first coolant and an evaporation path to evaporate
the second coolant passing therethrough. A heat transfer member may
be provided between the condensation and evaporation paths for heat
exchange between the first and second coolants.
[0031] The cascade heat exchanger 10 may be configured as a double
pipe heat exchanger where a condensation path and an evaporation
path are located inside and outside of a heat transfer member, or a
plate type heat exchanger where a condensation path and an
evaporation path are located alternate to each other with a heat
transfer member therebetween.
[0032] The cascade heat exchanger may be connected to first
expansion mechanism 12 and gas injection mechanism 5. The first
expansion mechanism expands the first coolant sucked into
evaporator 14 and may be configured as an electronic expansion
valve that may adjust the degree of opening to control the suction
superheat of the low temperature refrigeration cycle A.
[0033] The first expansion mechanism 12 may be connected to
evaporator 14 through a pipe 13 between the first expansion
mechanism and the evaporator. The evaporator may be configured as
an air-cooled heat exchanger that introduces external air into the
evaporator and evaporates the coolant using the introduced air. The
cascade cycle unit 4 may also include outdoor fan 15 that blows
external air into the evaporator.
[0034] The high temperature refrigeration cycle B forms a closed
path running from a high pressure side compressor 16 through a
water coolant heat exchanger 20 and a second expansion mechanism 22
to the cascade heat exchanger 10. The second coolant is compressed
in the high pressure side compressor 16, heat exchanged with water
and condensed in the water coolant heat exchanger 20, expanded in
the second expansion mechanism 22, and heat exchanged with the
first coolant and evaporated in the cascade heat exchanger. The
water may be heated while the second coolant repeats the
compression, condensation, expansion, and evaporation.
[0035] The high pressure side compressor 16, which compresses the
second coolant, may be connected to the water coolant heat
exchanger 20 via a high pressure side compressor discharge pipe 17.
The high pressure side compressor may be connected to the cascade
heat exchanger 10 via a high pressure side compressor suction pipe
18.
[0036] The water coolant heat exchanger 20 is connected to a water
circulation path that is a closed path including the room heating
unit 1 and the water heating unit 2.
[0037] The water coolant heat exchanger includes a condensation
path to condense a coolant passing therethrough and a water heating
path to heat water passing therethrough. The water coolant heat
exchanger may be configured as a double pipe heat exchanger where
the condensation path and the water heating path are located inside
and outside of a heat transfer member, or a plate type heat
exchanger where the condensation path and the water heating path
are located alternate to each other with a heat transfer member
therebetween.
[0038] The water coolant heat exchanger may be connected to second
expansion mechanism 22 through a pipe 21 between water coolant heat
exchanger 20 and second expansion mechanism 22. The second
expansion mechanism expands the second coolant sucked into cascade
heat exchanger 10 and may be configured as an electronic expansion
valve that may adjust the degree of opening to control the suction
superheat of the high temperature refrigeration cycle B.
[0039] The second expansion mechanism may be connected to cascade
heat exchanger 10 through a pipe 23 between second expansion
mechanism 22 and cascade heat exchanger 10.
[0040] The gas injection mechanism 5 may expand the first coolant
condensed in the cascade heat exchanger 10, separate a liquid
coolant and a gaseous coolant from the first coolant, and inject
only the gaseous coolant to low pressure side compressor 6.
[0041] The gas injection mechanism 5 may include a gas/liquid
separator 24 that separates a liquid coolant and a gaseous coolant
from the coolant condensed in the cascade heat exchanger 10, a
coolant injection path 26 that injects the gaseous coolant
separated by the gas/liquid separator 24 to the low pressure side
compressor 6, an auxiliary expansion mechanism 28 that expands the
coolant flowing from the cascade heat exchanger 10 to the
gas/liquid separator 24, and a gaseous coolant adjustment valve 30
that is provided over the coolant injection path 26.
[0042] The gas/liquid separator 24 may be provided between cascade
heat exchanger 10 and first expansion mechanism 12. The gas/liquid
separator may be connected to auxiliary expansion mechanism 28
through gas/liquid separator suction pipe 25, connected to the
first expansion mechanism through a liquid phase pipe 27, and
connected to the low pressure side compressor 6 through the coolant
injection path 26.
[0043] The coolant having passed through the auxiliary expansion
mechanism 28 flows into the gas/liquid separator 24 via a
gas/liquid separator suction pipe 25 and separates into a gaseous
coolant and a liquid coolant in the gas/liquid separator 24. The
gaseous coolant may be injected to the low pressure side compressor
6 through coolant injection path 26 and liquid coolant may flow
into first expansion mechanism 12 through the liquid phase pipe
27.
[0044] One end of coolant injection path 26 may be connected to
gas/liquid separator 24 and the other end may be connected to low
pressure side compressor 6.
[0045] The coolant injection path 26 may include a plurality of gas
injection pipes 26A and 26B. The gas injection pipes may include a
first gas injection pipe 26A that connects between gas/liquid
separator 24 and gaseous coolant adjustment valve 30, and a second
gas injection pipe 26B that connects between the gaseous coolant
adjustment valve 30 and the low pressure side compressor 6.
[0046] The auxiliary expansion mechanism 28 expands the coolant
condensed in the cascade heat exchanger 10 before the coolant is
sucked into the gas/liquid separator 24. The auxiliary expansion
mechanism may be provided between the cascade heat exchanger and
gas/liquid separator.
[0047] The auxiliary expansion mechanism 28 may be configured as an
electronic expansion valve that may adjust the degree of opening to
prevent the liquid coolant in the gas/liquid separator 24 from
flowing to the coolant injection path 26. The auxiliary expansion
mechanism may be connected to cascade heat exchanger 10 through a
pipe 29 between cascade heat exchanger 10 and auxiliary expansion
mechanism 28.
[0048] The gaseous coolant adjustment valve 30 controls the gaseous
coolant discharged from the second expansion mechanism 22. The
gaseous coolant adjustment valve 30 may be configured as an
opening/closing valve that performs the opening/closing operation
under the On/Off control, or an electronic expansion valve that may
control the degree of opening.
[0049] The water circulation path runs through the water coolant
heat exchanger 20, room heating unit 1, and water heating unit 2,
so that water heated in water coolant heat exchanger 20 passes
through at least one of the room heating unit 1 or the water
heating unit 2 and then returns to the water coolant heat exchanger
20.
[0050] The water circulation path may include a cascade cycle unit
pipe 32 that is located inside the refrigeration cycle apparatus 3,
a water heating pipe 33 that allows water to pass through the water
heating unit 2, a room heating pipe 34 that allows water to pass
through the room heating unit 1, and a connection pipe 35 that
connects the cascade cycle unit pipe 32 to the water heating pipe
33 and the room heating pipe 34.
[0051] A hot water adjustment valve 36 may be positioned over the
connection pipe 35 to guide the water heated in the water coolant
heat exchanger 20 to at least one of water heating pipe 33 and room
heating pipe 34. The water heating pipe and room heating pipe may
be connected to the water coolant heat exchanger through the
connection pipe.
[0052] The cascade cycle unit 4, room heating unit 1, and water
heating unit 2 will now be described in greater detail. The cascade
cycle unit may include a flow switch 37 that senses the flow of
water passing through the cascade cycle unit pipe 32 and a
circulation pump 38 that is positioned over the cascade cycle unit
pipe 32 to pump water for circulation.
[0053] The room heating unit may include a floor heating unit 41
that heats the floor of a room and an air heating unit 42 that
heats air in the room. The floor heating unit may be configured as
a meander line embedded in the floor of the room. The air heating
unit 42 may be configured as a fan coil unit or a radiator.
[0054] Room heating water adjustment valves 43 and 44 may be
positioned over the room heating pipe 34 to guide water to at least
one of the floor heating unit 41 and the air heating unit 42. The
floor heating unit 41 may be connected to the room heating water
adjustment valves via an air heating pipe 45, and the air heating
unit may be connected to the room heating water adjustment valves
via a floor heating pipe 46.
[0055] The water heating unit 2 supplies hot water required for a
user to take a shower or wash the dishes, and may include a hot
water tank 51 that contains water and a hot water auxiliary heater
52 that is provided in the hot water tank. The hot water tank may
be connected to a cool water inlet 53 that introduces cool water to
the hot water tank and a hot water outlet 54 that discharges hot
water out of the hot water tank 51. The water heating pipe 33 may
be provided in the hot water tank.
[0056] The hot water outlet 54 may be connected to a hot water
discharging device 55, such as a shower head. A cool water inlet 56
may be connected to the hot water outlet 54 so that cool water may
be discharged to the outside through the hot water discharging
device 55.
[0057] In the cascade cycle unit 4, the room healing unit 1, and
the water heating unit 2 as described above, if the hot water
adjustment valve 36 is subjected to a water heating mode for
supplying hot water when a circulation pump 39 is driven, water
heated in the water coolant heat exchanger 20 may flow through the
cascade cycle unit pipe 32 and the connection pipe 35 into the
water heating pipe 33 to heat water in the hot water tank 51 and
then return to the water coolant heat exchanger 20 via the
connection pipe 35 and the cascade cycle unit pipe 32.
[0058] If the hot water adjustment valve 36 is subjected to a room
heating mode for heating the room when the circulation pump 39 is
driven, the water heated through heat transfer with the second
coolant in the water coolant heat exchanger 20 may pass through the
cascade cycle unit pipe 32 and the connection pipe 35 into the room
heating pipe 34 to heat at least one of the floor heating unit 41
and the air heating unit 42 and then return to the water coolant
heat exchanger via the room heating pipe, the connection pipe, and
the cascade cycle unit pipe.
[0059] If the room heating water adjustment valves 43 and 44 are
subjected to an air heating mode for heating air in the room, the
water passes through the air heating pipe 45, the air heating unit
42, and the air heating pipe 45 to the room heating pipe 34, and if
the room heating water adjustment valves are subjected to a floor
heating mode for heating the floor in the room, the water passes
through the floor heating pipe 46, the floor heating unit 41, and
the floor heating pipe 46 to the room heating pipe.
[0060] In the first embodiment of the heat pump type
cooling/heating apparatus, the low pressure side compressor 6,
cascade heat exchanger 10, first expansion mechanism 12, evaporator
14, high pressure side compressor 16, water coolant heat exchanger
20, second expansion mechanism 22, coolant injection path 26,
gaseous coolant adjustment valve 30, gas/liquid separator 24, and
auxiliary expansion mechanism 28 may be installed together in a
single unit to constitute refrigeration cycle apparatus 3.
[0061] FIG. 2 shows a block diagram of the cooling/heating
apparatus of FIG. 1, FIG. 3 is an expanded view of the cascade
cycle unit of this apparatus, and FIG. 4 is a graph showing a P-H
relationship that may be obtained for the cooling/heating
apparatus.
[0062] As shown, the cooling/heating apparatus includes a
manipulation unit 60 that inputs instructions including
operation/stop instructions, a load sensor 70 that senses the load
of the apparatus, and a controller 80 that controls the low
pressure side compressor 6, first expansion mechanism 12, outdoor
fan 15, high pressure side compressor 16, second expansion
mechanism 22, auxiliary expansion mechanism 28, and gaseous coolant
adjustment valve 30 based on the operation of the manipulation unit
and the sensing result of the load sensor.
[0063] The load sensor 70 may include a hot water temperature
sensor that senses the load of room heating unit 1 and water
heating unit 2.
[0064] The hot water temperature sensor may be provided at a side
of the water circulation path to sense the temperature of water
circulating through the water coolant heat exchanger 20 and at
least one of the room heating unit or the water heating unit. In
one embodiment, the hot water temperature sensor senses the
temperature of water that is cooled in at least one of room heating
unit 1 or water heating unit 2 and then returns to the water
coolant heat exchanger. For example, the hot water temperature
sensor may be installed in the cascade cycle unit pipe 32.
[0065] The load sensor 70 may also include an outdoor temperature
sensor that determines whether the outdoor temperature is low or
not. This sensor may be in evaporator 14 to sense the temperature
of air blowing from the exterior to the evaporator.
[0066] If the load sensed by the load sensor is not less than a
predetermined load value, controller 80 may operate in an injection
mode in which gaseous coolant is injected through gas injection
mechanism 5. And, if the load sensed by the load sensor is not more
than a predetermined load value, the controller may operate in a
general mode that stops injecting the gaseous coolant through the
gas injection mechanism.
[0067] The controller controls the gaseous coolant adjustment valve
30 based on whether the operation mode is the general mode or gas
injection mode. In the general mode, the controller may close
gaseous coolant adjustment valve 30, and in the gas injection mode
the controller may open the gaseous coolant adjustment valve.
[0068] If the temperature of hot water sensed by the hot water
temperature sensor is less than a predetermined temperature value,
the controller may determine that the load is not less than the
predetermined load value to operate the cooling/heating apparatus,
especially the refrigeration cycle apparatus 3, in the gas
injection mode.
[0069] If the temperature of hot water sensed by the hot water
temperature sensor is not less than the predetermined temperature
value, the controller may determine that the load is less than the
predetermined load value to operate the cooling/heating apparatus,
especially the refrigeration cycle apparatus 3, in general
mode.
[0070] If the temperature of hot water sensed by the outdoor
temperature sensor is not more than a predetermined temperature
value, the controller may determine that the load is not less than
the predetermined load value to operate the cooling/heating
apparatus, especially the refrigeration cycle apparatus 3, in the
gas injection mode.
[0071] If the temperature of hot water sensed by the outdoor
temperature sensor is more than the predetermined temperature
value, the controller may determine that the load is less than the
predetermined load value to operate the cooling/heating apparatus,
especially the refrigeration cycle apparatus 3, in general
mode.
[0072] In response to an instruction from manipulation unit 60, the
controller drives low pressure side compressor 6 and high pressure
side compressor 16 and controls first expansion mechanism 12 and
second expansion mechanism 22 to enable the first and second
expansion mechanisms to expand the coolant. Further, the controller
may drive outdoor fan 15.
[0073] If the temperature sensed by load sensor 70 exceeds a
predetermined temperature value, the controller may close the
gaseous coolant adjustment valve 30. At this moment or shortly
thereafter, the controller may fully turn off the auxiliary
expansion mechanism 28.
[0074] During operation, the first coolant is compressed in low
pressure side compressor 6, condensed in cascade heat exchanger 10,
and directed to sequentially pass through auxiliary expansion
mechanism 28 and second expansion mechanism 22. The first coolant
is then expanded while passing through first expansion mechanism 12
and then a heat-exchange operation is performed with external air
to be evaporated while passing through evaporator 14. The first
coolant then returns to the low pressure side compressor.
[0075] While the first coolant is compressed in the low pressure
side compressor, the second coolant may be compressed in high
pressure side compressor 16, condensed in water coolant heat
exchanger 20 while heating water, expanded in second expansion
mechanism 22, evaporated while passing through cascade heat
exchanger 10 to exchange heat with the first coolant, and then
returned to the high pressure side compressor.
[0076] The refrigeration cycle apparatus 3 may heat water at higher
temperature than a case where low temperature refrigeration cycle A
alone or high temperature refrigeration cycle B alone is
included.
[0077] On the other hand, if the temperature sensed by load sensor
70 is not more than a predetermined temperature value, controller
80 may open gaseous coolant adjustment valve 30. At this moment or
shortly thereafter, the controller controls the auxiliary expansion
mechanism 28 to have a predetermined degree of opening in order to
enable the auxiliary expansion mechanism to expand the first
coolant. In addition to controlling the gaseous coolant adjustment
valve and auxiliary expansion mechanism, the controller may control
the other components in the same way as the general mode.
[0078] During the above-mentioned control, the first coolant may be
compressed in low pressure side compressor 6, condensed in cascade
heat exchanger 10, expanded in auxiliary expansion mechanism 28,
and then introduced into second expansion mechanism 22.
[0079] The first coolant is separated into a gaseous coolant and a
liquid coolant in the second expansion mechanism. The liquid
coolant may be expanded while flowing into first expansion
mechanism 12, evaporate in evaporator 14, and then sucked and
compressed in low pressure side compressor 6. On the other hand,
the gaseous coolant may pass from second expansion mechanism 22
through coolant injection path 26 and gaseous coolant adjustment
valve 30 and injected into the low pressure side compressor for
compression.
[0080] In general mode, while the first coolant goes through
compression, condensation, expansion, and evaporation procedures,
refrigeration cycle apparatus 3 is subjected to a cycle:
a->b->c->f->a, as depicted by the dashed lines in FIG.
4.
[0081] In gas injection mode, while the first coolant goes through
compression, condensation, expansion, expansion, and evaporation
procedures, the refrigeration cycle apparatus 3 is subjected to a
cycle: a->b->c->d->e->f->a, as depicted by the
solid lines in FIG. 4. Also, part of the coolant discharged from
cascade heat exchanger 10 is subjected to a procedure:
c->d->g->b as depicted in FIG. 4 while going through
expansion and compression, so that the cascade heat exchanger may
have an increased condensation volume compared to the normal
mode.
[0082] On the other hand, the second coolant may be compressed in
high pressure side compressor 16 while the first coolant is
compressed in low pressure side compressor 6. The second coolant
may be condensed while water is heated in water coolant heat
exchanger 20, expanded in second expansion mechanism 22, heat
exchanged with the first coolant and evaporated while passing
through cascade heat exchanger 10, and then returned to high
pressure side compressor 16. The refrigeration cycle apparatus 3
perform compression, condensation, expansion, and evaporation while
the second coolant goes through a cycle:
h->I->j->k->h.
[0083] That is, the refrigeration cycle apparatus may have further
reduced compression work in the gas injection mode than the general
mode, and may supply hot water to the refrigeration cycle apparatus
even when the temperature at the exterior is low and the apparatus
is located in a cold site.
[0084] FIG. 5 shows a second embodiment of a heat pump type
cooling/heating apparatus, wherein a gas injection mechanism 5' may
be provided in high temperature refrigeration cycle B. The gas
injection mechanism 5' may be provided between second expansion
mechanism 22 and water coolant heat exchanger 20 of the high
temperature refrigeration cycle B and connected to high pressure
side compressor 16' of high temperature refrigeration cycle B.
[0085] In low temperature refrigeration cycle A, a low pressure
side compressor 6' may be connected to cascade heat exchanger 10
via a low pressure side compressor discharge pipe 7 and connected
to evaporator 14 via a low pressure side compressor suction pipe
8.
[0086] In low temperature refrigeration cycle A, first expansion
mechanism 12 may be connected to cascade heat exchanger 10 via a
pipe 11 between first expansion mechanism 12 and cascade heat
exchanger 10 and connected to evaporator 14 via a pipe 13 between
the first expansion mechanism and evaporator 14.
[0087] In high temperature refrigeration cycle B, high pressure
side compressor 16' may be configured as a two stage compressor, a
twin rotary compressor, a screw compressor, or a scroll compressor
so that the gaseous coolant having passed through gas injection
mechanism 5' is gas injected to high pressure side compressor
16'.
[0088] The high pressure side compressor 16' may be similar to high
pressure side compressor 16, and may be connected to water coolant
heat exchanger 20 via high pressure side compressor discharge pipe
17 and to cascade heat exchanger 10 via high pressure side
compressor suction pipe 18.
[0089] The gas injection mechanism 5' may expand the second coolant
condensed in water coolant heat exchanger 20, separate the second
coolant into a gaseous coolant and a liquid coolant, and then
inject only the gaseous coolant into high pressure side compressor
16'.
[0090] The gas injection mechanism 5' may include a gas/liquid
separator 24' that separates a liquid coolant and a gaseous coolant
from the coolant condensed in water coolant heat exchanger 20, a
coolant injection path 26' that injects the gaseous coolant
separated by gas/liquid separator 24' to high pressure side
compressor 16', an auxiliary expansion mechanism 28' that expands
the coolant flowing from water coolant heat exchanger 20 to
gas/liquid separator 24', and a gaseous coolant adjustment valve
30' that is provided over gas/liquid separator 24'.
[0091] The gas/liquid separator 24' may be provided between water
coolant heat exchanger 20 and second expansion mechanism 22, and
may be connected to auxiliary expansion mechanism 28' through a
gas/liquid separator suction pipe 25', to second expansion
mechanism 22 through a liquid phase pipe 27', and to high pressure
side compressor 16' through a coolant injection path 26'.
[0092] Once having passed through the auxiliary expansion mechanism
28', the coolant flows into gas/liquid separator 24' via gas/liquid
separator suction pipe 25' and separates into a gaseous coolant and
a liquid coolant in the gas/liquid separator 24'. The gaseous
coolant may be injected to high pressure side compressor 16'
through coolant injection path 26' and the liquid coolant may flow
into second expansion mechanism 22 through liquid phase pipe 27'.
One end of coolant injection path 26' may be connected to
gas/liquid separator 24' and the other end may be connected to high
pressure side compressor 16'.
[0093] The coolant injection path 26' may include a plurality of
gas injection pipes 26A' and 26B'. These pipes may include a first
gas injection pipe 26A' that is connected between gas/liquid
separator 24' and gaseous coolant adjustment valve 30' and a second
gas injection pipe 26B' that is connected between gaseous coolant
adjustment valve 30' and high pressure side compressor 16'.
[0094] The auxiliary expansion mechanism 28' expands the coolant
condensed in water coolant heat exchanger 20 before the coolant is
sucked into gas/liquid separator 24'. The auxiliary expansion
mechanism may be provided between water coolant heat exchanger 20
and gas/liquid separator 24', and may be configured as an
electronic expansion valve for adjusting the degree of opening to
prevent the liquid coolant in gas/liquid separator 24' from flowing
to coolant injection path 26'.
[0095] The auxiliary expansion mechanism 28' may be connected to
water coolant heat exchanger 20 through a pipe 29' between the
water coolant heat exchanger and the auxiliary expansion mechanism.
The gaseous coolant adjustment valve 30' controls the gaseous
coolant discharged from the gas/liquid separator 24', and may be
configured as an opening/closing valve that performs the
opening/closing operation under the On/Off control, or an
electronic expansion valve that may control the degree of
opening.
[0096] FIG. 6 shows a third embodiment of a heat pump type
cooling/heating apparatus, FIG. 7 shows a manner in which a cascade
unit and outdoor unit may be separately provided in this apparatus,
and FIG. 8 shows a manner in which the outdoor unit may be attached
to the cascade unit in this apparatus.
[0097] As shown, the third embodiment may include an outdoor unit O
and a cascade unit C. The outdoor unit O may include low pressure
side compressor 6, first expansion mechanism 12, evaporator 14, and
outdoor fan 15. The cascade unit C may include cascade heat
exchanger 10, high pressure side compressor 16, water coolant heat
exchanger 20, and second expansion mechanism 22.
[0098] In case of being provided in low temperature refrigeration
cycle A, gas injection mechanism 5 may be included in the outdoor
unit O, and in case of being provided in high temperature
refrigeration cycle B the gas injection mechanism may be included
in the cascade unit C.
[0099] The cascade unit C may be separated from outdoor unit C as
shown in FIG. 7, in which the refrigeration cycle apparatus 3 may
be considered as a separation type. Alternatively, the cascade unit
may be attached to the outdoor unit C as shown in FIG. 8, in which
case the refrigeration cycle apparatus 3 may be considered as an
integration type. The cascade unit C may be selectively mounted on
the outdoor unit O.
[0100] One or more embodiments described herein, therefore,
provides a heat pump type cooling/heating apparatus that may
efficiently provide a supply of hot water as needed. One or more of
these embodiments may also provide a heat pump type cooling/heating
apparatus that enhances heating performance by preventing a
lowering in efficiency in cold regions in which the apparatus is
being used.
[0101] In accordance with one embodiment, a heat pump type
cooling/heating apparatus includes a cascade cycle unit that
includes a cascade heat exchanger that performs a heat exchange
between a first coolant of a low temperature refrigeration cycle
and a second coolant of a high temperature refrigeration cycle, and
a water coolant heat exchanger that heats water while the second
coolant of the high temperature refrigeration cycle is
condensed.
[0102] The water coolant heat exchanger is connected to a
destination via a water circulation path including: a coolant
injection path that is split between the cascade heat exchanger and
an evaporator of the low temperature refrigeration cycle to inject
a coolant into a low pressure side compressor of the low
temperature refrigeration cycle or split between the water coolant
heat exchanger and the cascade heat exchanger to inject a coolant
into a high pressure side compressor of the high temperature
refrigeration cycle; and a gaseous coolant adjustment valve that is
provided in the coolant injection path and adjusted corresponding
to the load of the destination.
[0103] In another embodiment, a heat pump type cooling/heating
apparatus includes a gas/liquid separator that separates a coolant
condensed in the cascade heat exchanger into a liquid coolant and a
gaseous coolant; and an auxiliary expansion mechanism that is
provided between the cascade heat exchanger and the gas/liquid
separator to expand a coolant.
[0104] The low temperature refrigeration cycle may forms a closed
path running from a low pressure side compressor through the
cascade heat exchanger and a first expansion mechanism to an
evaporator, and the high temperature refrigeration cycle forms a
closed path running from a high pressure side compressor through
the water coolant heat exchanger and a second expansion mechanism
to the cascade heat exchanger, and wherein the gas/liquid separator
is provided between the cascade heat exchanger and the first
expansion mechanism.
[0105] In another embodiment, the heat pump type cooling/heating
apparatus further includes a gas/liquid separator that separates a
coolant condensed in the water coolant heat exchanger into a liquid
coolant and a gaseous coolant; and an auxiliary expansion mechanism
that is provided between the water coolant heat exchanger and the
gas/liquid separator to expand a coolant.
[0106] The low temperature refrigeration cycle forms a closed path
running from a low pressure side compressor through the cascade
heat exchanger and a first expansion mechanism to an evaporator,
and the high temperature refrigeration cycle forms a closed path
running from a high pressure side compressor through the water
coolant heat exchanger and a second expansion mechanism to the
cascade heat exchanger, and wherein the gas/liquid separator is
provided between the water coolant heat exchanger and the second
expansion mechanism.
[0107] The low pressure side compressor, the cascade heat
exchanger, the first expansion mechanism, the evaporator, the high
pressure side compressor, the second expansion mechanism, the water
coolant heat exchanger, the coolant injection path, the gaseous
coolant adjustment valve, the gas/liquid separator, and the
auxiliary expansion mechanism are installed in a single unit.
[0108] The low pressure compressor, the first expansion mechanism,
and the evaporator are installed in an outdoor unit, and wherein
the cascade heat exchanger, the high pressure side compressor, the
second expansion mechanism, and the water coolant heat exchanger
are installed in a cascade unit, and wherein the coolant injection
path, the gaseous coolant adjustment valve, the gas/liquid
separator, and the auxiliary expansion mechanism are installed in
one of the outdoor unit and the cascade unit. The cascade unit may
be integrally mounted on the outdoor unit or may be provided
separately from the outdoor unit.
[0109] The heat pump type cooling/heating apparatus further
includes a load sensor that senses the load of the destination; and
a controller that controls the gaseous coolant adjust valve
according to a sensing result of the load sensor. The load sensor
is provided over the water circulation path. The controller opens
the gaseous coolant adjustment valve when a temperature sensed by
the load sensor is less than a predetermined valve, and closes the
gaseous coolant adjustment valve when a temperature sensed by the
load sensor is more than the predetermined valve. The destination
includes a room heating unit connected to the water circulation
path and a water heating unit connected to the water circulation
path.
[0110] At least one of the low pressure side compressor and the
high pressure compressor, which is connected to the coolant
injection path, is configured as a two stage compressor.
[0111] At least one of the low pressure side compressor and the
high pressure compressor, which is connected to the coolant
injection path, is configured as a screw compressor.
[0112] At least one of the low pressure side compressor and the
high pressure compressor, which is connected to the coolant
injection path, is configured as a scroll compressor.
[0113] At least one of the low pressure side compressor and the
high pressure compressor, which is connected to the coolant
injection path, is configured as a twin rotary compressor.
[0114] One or more embodiments of the heat pump type
cooling/heating apparatus may include the cascade heat exchanger
with the low temperature refrigeration cycle and the high
temperature refrigeration cycle, and thus, may make the temperature
of water supplied to the apparatus higher than the conventional
apparatuses having a single refrigeration cycle. Further, since the
gaseous coolant is gas injected into the compressor over the low
temperature cycle or compressor over the high temperature cycle,
thus capable of enhancing heating performance.
[0115] Since the gaseous coolant is gas injected into the low
pressure side compressor over the low temperature refrigeration
cycle, it may be possible to minimize a lowering in volume flow
rate that occurs at the evaporator over the low temperature
refrigeration cycle when the temperature of the exterior is low.
Additionally, the condensation volume of the cascade heat exchanger
may be raised, and this allows for efficient room heating and high
defrosting performance.
[0116] Since the gaseous coolant is gas injected into the
compressor over the low temperature refrigeration cycle, it may be
possible to lower the maximum management temperature of the
compressor over the low temperature refrigeration cycle and enhance
reliability of the compressor over the low temperature
refrigeration cycle.
[0117] Since the gaseous coolant is gas injected into the high
pressure side compressor over the high temperature refrigeration
cycle, it may be possible to increase the condensation volume of
the water coolant heat exchanger, thus leading to improving room
heating performance and supplying water at higher temperature.
[0118] Any reference in this specification to "one embodiment," "an
embodiment," "example embodiment," etc., means that a particular
feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment of the
invention. The appearances of such phrases in various places in the
specification are not necessarily all referring to the same
embodiment. Further, when a particular feature, structure, or
characteristic is described in connection with any embodiment, it
is submitted that it is within the purview of one skilled in the
art to effect such feature, structure, or characteristic in
connection with other ones of the embodiments.
[0119] Although embodiments have been described with reference to a
number of illustrative embodiments thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this disclosure. More particularly, various
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the disclosure, the drawings and the appended claims.
In addition to variations and modifications in the component parts
and/or arrangements, alternative uses will also be apparent to
those skilled in the art.
* * * * *