U.S. patent application number 15/375456 was filed with the patent office on 2017-06-01 for vehicle air conditioning apparatus.
This patent application is currently assigned to Sanden Holdings Corporation. The applicant listed for this patent is Sanden Holdings Corporation. Invention is credited to Kenichi SUZUKI, Hidenori TAKEI.
Application Number | 20170151857 15/375456 |
Document ID | / |
Family ID | 48574111 |
Filed Date | 2017-06-01 |
United States Patent
Application |
20170151857 |
Kind Code |
A1 |
SUZUKI; Kenichi ; et
al. |
June 1, 2017 |
VEHICLE AIR CONDITIONING APPARATUS
Abstract
In a vehicle air conditioning apparatus, during a cooling
operation, and a cooling and dehumidifying operation, a refrigerant
flows through an outdoor heat exchanger, flows through a
supercooling radiator, and then flows into a radiator to absorb
heat. During a heating operation, the refrigerant flows through a
heat exchanger and then is sucked into a compressor without passing
through the supercooling radiator. During a first heating and
dehumidifying operation, the refrigerant flows through another
radiator, flows through the supercooling radiator, and then flows
into another heat exchanger to absorb heat.
Inventors: |
SUZUKI; Kenichi;
(Isesaki-Shi, JP) ; TAKEI; Hidenori; (Isesaki-Shi,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sanden Holdings Corporation |
Isesaki-Shi |
|
JP |
|
|
Assignee: |
Sanden Holdings Corporation
Isesaki-Shi
JP
|
Family ID: |
48574111 |
Appl. No.: |
15/375456 |
Filed: |
December 12, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14363892 |
Jun 9, 2014 |
|
|
|
PCT/JP2012/080470 |
Nov 26, 2012 |
|
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15375456 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25B 2700/197 20130101;
F25B 41/003 20130101; F25B 6/02 20130101; F25B 2700/2106 20130101;
B60H 2001/326 20130101; F25B 6/04 20130101; B60H 1/00021 20130101;
B60H 2001/3257 20130101; F25B 1/005 20130101; B60H 1/3227 20130101;
F25B 2700/1933 20130101; F25B 2700/21175 20130101; B60H 1/00064
20130101; F25B 47/022 20130101; F25B 2700/21151 20130101; F25B
2400/04 20130101; F25B 2700/1931 20130101; F25B 2700/21163
20130101; B60H 1/00921 20130101; F25B 40/00 20130101; B60H
2001/00092 20130101; F25B 2700/195 20130101; F25B 29/003 20130101;
F25B 49/02 20130101; B60H 2001/325 20130101; F25B 5/00 20130101;
B60H 1/00392 20130101; F25B 2700/21152 20130101; B60H 1/00907
20130101; F25D 21/06 20130101; F25B 41/04 20130101; B60H 2001/3251
20130101 |
International
Class: |
B60H 1/00 20060101
B60H001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 9, 2011 |
JP |
2011-270685 |
Claims
1. A vehicle air conditioning apparatus comprising: a compressor
configured to compress and discharge a refrigerant; a radiator
configured to release heat from the refrigerant; a heat exchanger
configured to absorb the heat into the refrigerant; an outdoor heat
exchanger configured to release the heat from or absorb the heat
into the refrigerant; an outdoor radiator configured to further
release the heat from the refrigerant having released the heat in
the outdoor heat exchanger; a cooling/cooling and dehumidifying
refrigerant circuit configured to allow the refrigerant discharged
from the compressor to flow into the radiator, to allow the
refrigerant having passed through the radiator to flow into the
outdoor heat exchanger, to allow the refrigerant having passed
through the outdoor heat exchanger to flow into the outdoor
radiator, to allow the refrigerant having passed through the
outdoor radiator to flow into the heat exchanger via an expansion
valve and to allow the refrigerant having passed through the heat
exchanger to be sucked into the compressor; and a heating
refrigerant circuit configured to allow the refrigerant discharged
from the compressor to flow into the radiator, to allow the
refrigerant having passed through the radiator to flow into the
outdoor heat exchanger via an expansion part, and to allow the
refrigerant having passed through the outdoor heat exchanger to be
sucked into the compressor, wherein a refrigerant flow path is
formed in the outdoor heat exchanger, the refrigerant flowing into
a first end of the refrigerant flow path and being discharged from
a second end of the refrigerant flow path.
2. The vehicle air conditioning apparatus according to claim 1,
wherein the refrigerant flow path is formed in the outdoor heat
exchanger; for heat release, the refrigerant flows into a first end
of the refrigerant flow path, releases the heat, and is discharged
from a second end; meanwhile, for heat absorption, the refrigerant
flows into the second end of the refrigerant flow path, absorbs the
heat, and is discharged from the first end.
3. The vehicle air conditioning apparatus according to claim 1,
further comprising a receiver tank configured to be able to
accumulate a liquid refrigerant, the receiver tank being provided
upstream from the outdoor radiator in a refrigerant flow direction;
an outdoor heat exchanger unit including the outdoor heat
exchanger, the outdoor radiator, the receiver tank, a refrigerant
flow passage that connects between the outdoor heat exchanger and
the receiver tank; and a valve provided in the refrigerant flow
passage, which are integrally formed. (FIG. 2)
4. The vehicle air conditioning apparatus according to claim 3,
wherein the valve is formed integrally with the outdoor heat
exchanger unit, the valve being provided in a refrigerant flow
passage connected to the refrigerant flow passage that connects
between the outdoor heat exchanger and the receiver tank.
5. The vehicle air conditioning apparatus according to claim 4,
wherein the valve is formed integrally with the outdoor heat
exchanger unit, the valve being provided in a refrigerant flow
passage that connects between the outdoor heat exchanger and the
compressor.
6. The vehicle air conditioning apparatus according to claim 5,
wherein the valve is formed integrally with the outdoor heat
exchanger unit, the valve being provided in a refrigerant flow
passage that connects between the radiator and the outdoor heat
exchanger.
7. A vehicle air conditioning apparatus comprising: a compressor
configured to compress and discharge a refrigerant; a radiator
configured to release heat from the refrigerant; a heat exchanger
configured to absorb the heat into the refrigerant; an outdoor heat
exchanger configured to release the heat from or absorb the heat
into the refrigerant; an outdoor radiator configured to further
release the heat from the refrigerant having released the heat in
the outdoor heat exchanger; a cooling/cooling and dehumidifying
refrigerant circuit configured to allow the refrigerant discharged
from the compressor to flow into the radiator, to allow the
refrigerant having passed through the radiator to flow into the
outdoor heat exchanger, to allow the refrigerant having passed
through the outdoor heat exchanger to flow into the outdoor
radiator, to allow the refrigerant having passed through the
outdoor radiator to flow into the heat exchanger via an expansion
valve and to allow the refrigerant having passed through the heat
exchanger to be sucked into the compressor; and a heating
refrigerant circuit configured to allow the refrigerant discharged
from the compressor to flow into the radiator, to allow the
refrigerant having passed through the radiator to flow into the
outdoor heat exchanger via an expansion part, and to allow the
refrigerant having passed through the outdoor heat exchanger to be
sucked into the compressor, further comprising a control valve
unit, wherein the control valve unit comprises: an expansion part
configured to decompress the refrigerant flowing into the outdoor
heat exchanger when the refrigerant absorbs the heat in the outdoor
heat exchanger; and a flow regulating part configured to regulate
an amount of the refrigerant flowing into the outdoor heat
exchanger when the refrigerant releases the heat in the outdoor
heat exchanger, wherein the expansion part and the flow regulating
part are integrally formed, wherein each of the expansion part and
the flow regulating part has a refrigerant inlet and an refrigerant
outlet, and the control valve includes a piping connection port
configured to allow communication with at least the refrigerant
inlet of each of the expansion part and the flow regulating
part.
8. The vehicle air conditioning apparatus according to claim 7,
wherein the expansion part is an electronic expansion valve and the
flow regulating part is a solenoid valve.
9. The vehicle air conditioning apparatus according to claim 7,
wherein the control valve unit includes a three-way valve that can
switch the refrigerant outlet from one to the other and an
expansion valve provided in the refrigerant outlet.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application
Ser. No. 14/363,892, filed on Jun. 9, 2014, which is a U.S.
national phase application under 35 U.S.C. .sctn.371 of
International Patent Application No. PCT/JP2012/080470, filed on
Nov. 26, 2012, and claims benefit of priority to Japanese Patent
Application No. 2011-270685, filed on Dec. 9, 2011. The
International Application was published on Jun. 13, 2013, as
International Publication No. WO 2013/084737 under PCT Article
21(2). The entire contents of these applications are hereby
incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to a vehicle air conditioning
apparatus applicable to, for example, electric cars.
BACKGROUND
[0003] Conventionally, this sort of vehicle air conditioning
apparatus includes: a compressor driven by an engine as a power
source of a vehicle; a radiator provided outside the vehicle
interior; and a heat exchanger provided in the vehicle interior.
With this vehicle air conditioning apparatus, a cooling operation
is performed by: releasing the heat from the refrigerant discharged
from the compressor in the radiator; absorbing the heat into the
refrigerant in the heat exchanger; and supplying the air subjected
to a heat exchange with the refrigerant in the heat exchanger to
the vehicle interior. In addition, such a conventional vehicle air
conditioning apparatus includes a heater core and perform a heating
operation by: releasing the exhaust heat from the cooling water
used to cool the engine in the heater core; and blowing the air
subjected to a heat exchange with the cooling water in the heater
core to the vehicle interior. Moreover, such a conventional vehicle
air conditioning apparatus performs a heating and dehumidifying
operation by: cooling the air to be supplied to the vehicle
interior to a required absolute humidity in the heat exchanger for
dehumidification; heating the cooled and dehumidified air in the
heat exchanger to a desired temperature in the heater core; and
blowing the heated air to the vehicle interior.
[0004] The above-mentioned vehicle air conditioning apparatus uses
the exhaust heat from the engine as a heat source to heat the air
for a heating operation, or a heating and dehumidifying operation.
Generally, an electric car uses an electric motor as a power
source, and it is difficult to acquire the exhaust heat that can
heat the air by using the electric motor without an engine.
Therefore, the above-mentioned vehicle air conditioning apparatus
is not applicable to electric cars.
[0005] To address this issue, there has been known a vehicle air
conditioning apparatus which is applicable to electric cars. The
vehicle air conditioning apparatus includes: a compressor
configured to compress and discharge a refrigerant; a radiator
configured to release the heat from the refrigerant; a heat
exchanger configured to absorb the heat into the refrigerant; an
outdoor heat exchanger configured to release the heat from or
absorb the heat into the refrigerant; [0006] a heating operation
refrigerant circuit configured to allow the refrigerant discharged
from the compressor to flow into the radiator, to allow the
refrigerant having passed through the radiator to flow into the
outdoor heat exchanger via the expansion part, and to allow the
refrigerant having passed through the outdoor heat exchanger to
flow into the compressor; [0007] a heating and dehumidifying
refrigerant circuit configured to allow the refrigerant discharged
from the compressor to flow into the radiator, to allow part of the
refrigerant having passed through the radiator to flow into the
heat exchanger via the expansion part, to allow the remaining
refrigerant to flow into the outdoor heat exchanger via the
expansion part, and to allow the refrigerant having passed through
the heat exchanger and the refrigerant having passed through the
outdoor heat exchanger to be sucked into the compressor; [0008] and
a cooling and dehumidifying refrigerant circuit configured to allow
the refrigerant discharged from the compressor to flow into the
radiator, to allow the refrigerant having passed through the
radiator to flow into the outdoor heat exchanger, to allow the
refrigerant having passed through the outdoor heat exchanger to
flow into the heat exchanger via the expansion part, and to allow
the refrigerant having passed through the heat exchanger to be
sucked into the compressor (see, for example, Japanese Patent
Application Laid-Open No. 2001-324237).
SUMMARY
[0009] It has been known that the vehicle air conditioning
apparatus may improve the efficiency of the cooling operation and
the cooling and dehumidifying operation by releasing the heat from
the refrigerant to supercool the refrigerant in the cooling/cooling
and dehumidifying refrigerant circuit when the refrigerant is
decompressed in the outdoor heat exchanger. In order to release the
heat from the refrigerant to supercool the refrigerant in the
outdoor heat exchanger, a supercooling part is provided to flow
refrigerant into the outdoor heat exchanger in the downstream side
of the refrigerant flow direction.
[0010] However, in a case in which the supercooling part is
provided in the outdoor heat exchanger, if a refrigerant circuit in
addition to the cooling/cooling and dehumidifying refrigerant
circuit is provided, pressure loss is increased because the
refrigerant flows through the supercooling part. This may cause a
decrease in efficiency in operations other than the cooling
operation and the cooling/cooling and dehumidifying operation.
[0011] It is therefore an object of the present invention to
provide a vehicle air conditioning apparatus that can decrease
pressure loss, and therefore improve the efficiency of air
conditioning operation.
[0012] To achieve the object, the vehicle air conditioning
apparatus according to the present invention includes: a compressor
configured to compress and discharge a refrigerant; a radiator
configured to release heat from the refrigerant; a heat exchanger
configured to absorb the heat into the refrigerant; an outdoor heat
exchanger configured to release the heat from or absorb the heat
into the refrigerant; an outdoor radiator configured to further
release the heat from the refrigerant having released the heat in
the outdoor heat exchanger; a cooling/cooling and dehumidifying
refrigerant circuit configured to allow the refrigerant discharged
from the compressor to flow into the radiator, to allow the
refrigerant having passed through the radiator to flow into the
outdoor heat exchanger, to allow the refrigerant having passed
through the outdoor heat exchanger to flow into the outdoor
radiator, to allow the refrigerant having passed through the
outdoor radiator to flow into the heat exchanger via an expansion
valve and to allow the refrigerant having passed through the heat
exchanger to be sucked into the compressor; and a heating
refrigerant circuit configured to allow the refrigerant discharged
from the compressor to flow into the radiator, to allow the
refrigerant having passed through the radiator to flow into the
outdoor heat exchanger via an expansion part, and to allow the
refrigerant having passed through the outdoor heat exchanger to be
sucked into the compressor.
[0013] By this means, the refrigerant having passed through the
outdoor radiator flows into the radiator in the cooling/cooling and
dehumidifying refrigerant circuit, meanwhile the refrigerant having
passed through the outdoor heat exchanger is sucked into the
compressor without passing through the outdoor radiator.
[0014] According to the present invention, the refrigerant having
passed through the heat exchanger is supercooled in the outdoor
radiator, and therefore it is possible to improve the efficiency of
the air conditioning operation. Moreover, the refrigerant not
having passed through the heat exchanger is sucked into the
compressor without passing through the supercooling radiator.
Therefore, it is possible to reduce pressure loss, and consequently
improve the efficiency of the air conditioning operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic view showing a vehicle air
conditioning apparatus according to Example 1 of the present
invention;
[0016] FIG. 2 shows an outdoor heat exchanger unit;
[0017] FIG. 3A is a graph showing the relationship between a valve
opening signal and an opening area of the expansion part of the
first control valve;
[0018] FIG. 3B is a graph showing the relationship between a valve
opening signal and an opening area of the condensing pressure
regulating part of the first control valve;
[0019] FIG. 3C is a graph showing the relationship between a valve
opening signal and an opening area of the combination of the
expansion part and the condensing pressure regulating part of the
first control valve;
[0020] FIG. 4 is a schematic view showing the vehicle air
conditioning apparatus performing a cooling operation and a cooling
and dehumidifying operation;
[0021] FIG. 5 is a schematic view showing the vehicle air
conditioning apparatus performing a heating operation;
[0022] FIG. 6 is a schematic view showing the vehicle air
conditioning apparatus performing a first heating and dehumidifying
operation;
[0023] FIG. 7 is a schematic view showing the vehicle air
conditioning apparatus performing a second heating and
dehumidifying operation;
[0024] FIG. 8 is a schematic view showing the vehicle air
conditioning apparatus performing a defrosting operation;
[0025] FIG. 9 is a table showing the states of the control valve in
each operation;
[0026] FIG. 10 is a flowchart showing a determination process for a
second heating and dehumidifying operation;
[0027] FIG. 11 is a flowchart showing a process for switching to a
second heating and dehumidifying operation;
[0028] FIG. 12 is a flowchart showing a process for controlling
operation switching;
[0029] FIG. 13 is a schematic view showing the vehicle air
conditioning apparatus according to Example 2 of the present
invention;
[0030] FIG. 14 is a table showing the states of the control valve
in each operation;
[0031] FIG. 15 is a schematic view showing the vehicle air
conditioning apparatus according to Example 3 of the present
invention;
[0032] FIG. 16 is a table showing the states of the control valve
in each operation;
[0033] FIG. 17 is a schematic view showing the vehicle air
conditioning apparatus according to Example 4 of the present
invention;
[0034] FIG. 18 is a table showing the states of the control valve
in each operation;
[0035] FIG. 19 is a schematic view showing the vehicle air
conditioning apparatus according to Example 5 of the present
invention;
[0036] FIG. 20 shows the outdoor heat exchanger unit;
[0037] FIG. 21A is a graph showing the relationship between the
valve opening and the opening area of each of the expansion part
and the condensing pressure regulating part of the first control
valve;
[0038] FIG. 21B is a graph showing the relationship between the
valve opening and the opening area of each of the expansion part
and the condensing pressure regulating part of another example of
the first control valve;
[0039] FIG. 21C is a graph showing the relationship between the
valve opening and the opening area of each of the expansion part
and the condensing pressure regulating part of further another
example of the first control valve;
[0040] FIG. 22A shows the structure of the expansion part of the
first control valve shown in FIG. 21c when the small diameter valve
closes the refrigerant flow channel to the valve body;
[0041] FIG. 22B shows the structure of the expansion part of the
first control valve shown in FIG. 21c when the valve element moves
upward to open the refrigerant flow channel;
[0042] FIG. 22C shows the structure of the expansion part of the
first control valve shown in FIG. 21c and the valve element moves
upward to move the valve seat upward;
[0043] FIG. 23A shows the first control valve formed integrally
with the check valve;
[0044] FIG. 23B shows another example of the first control valve
and the check valve;
[0045] FIG. 23C shows a further example of the first control valve
and the check valve;
[0046] FIG. 24 is a schematic view showing the vehicle air
conditioning apparatus performing a cooling operation and a cooling
and dehumidifying operation;
[0047] FIG. 25 is a schematic view showing the vehicle air
conditioning apparatus performing a heating operation;
[0048] FIG. 26 is a schematic view showing the vehicle air
conditioning apparatus performing a first heating and dehumidifying
operation;
[0049] FIG. 27 is a schematic view showing the vehicle air
conditioning apparatus performing a second heating and
dehumidifying operation;
[0050] FIG. 28 is a schematic view showing the vehicle air
conditioning apparatus performing a defrosting operation;
[0051] FIG. 29 is a table showing the states of the control valve
in each operation;
[0052] FIG. 30 is a schematic view showing the vehicle air
conditioning apparatus according to Example 6 of the present
invention; and
[0053] FIG. 31 is a table showing the states of the control valve
in each operation.
DETAILED DESCRIPTION
[0054] FIG. 1 to FIG. 12 show Example 1 of the present
invention.
[0055] As shown in FIG. 1, the vehicle air conditioning apparatus
according to the present invention includes an air conditioning
unit 10 provided in the vehicle interior, and a refrigerant circuit
20 formed across the vehicle interior and the outdoor.
[0056] The air conditioning unit 10 includes an air flow passage 11
that allows the air to be supplied to the vehicle interior to pass
through. An outdoor air inlet 11a and an indoor air inlet 11b are
provided in the first end side of the air flow passage 11. The
outdoor air inlet 11a is configured to allow the outdoor air to
flow into the air flow passage 11, and the indoor air inlet 11b is
configured to allow the indoor air to flow into the air flow
passage 11. Meanwhile, a foot outlet 11c, a vent outlet 11d and a
defroster outlet 11e are provided in the second end side of the air
flow passage 11. The foot outlet 11c is configured to allow the air
flowing through the air flow passage 11 to blow to the feet of the
passengers in the vehicle. The vent outlet 11d is configured to
allow the air flowing through the air flow passage 11 to blow to
the upper bodies of the passengers in the vehicle. The defroster
outlet 11e is configured to allow the air flowing through the air
flow passage 11 to blow to the interior surface of the front
window.
[0057] An indoor fan 12 such as a sirocco fan configured to allow
the air to flow through the air flow passage 11 from end to end is
provided in the first end side of the air flow passage 11.
[0058] Also, in the first end side of the air flow passage 11, an
inlet switching damper 13 configured to open one of the outdoor air
inlet 11a and the indoor air inlet 11b and to close the other. When
the inlet switching damper 13 closes the indoor air inlet 11b and
opens the outdoor air inlet 11a, the mode is switched to an outdoor
air supply mode in which the air flows from the outdoor air inlet
11a into the air flow passage 11. Meanwhile, when the inlet
switching damper 13 closes the outdoor air inlet 11a and opens the
indoor air inlet 11b, the mode is switched to an indoor air
circulation mode in which the air flows from the indoor air inlet
11b into the air flow passage 11. Moreover, when the inlet
switching damper 13 is placed between the outdoor air inlet 11a and
the indoor air inlet 11b and the outdoor air inlet 11a and the
indoor air inlet 11b open, the mode is switched to a two-way mode
in which the air flows from both the outdoor air inlet 11a and the
indoor air inlet 11b into the air flow passage 11 according to the
opening ratio of the outdoor air inlet 11a and the indoor air inlet
11b.
[0059] Outlet switching dampers 13b, 13c and 13d configured to open
and close the foot outlet 11c, the vent outlet 11d and the
defroster outlet 11e are provided in the foot outlet 11c, the vent
outlet 11d and the defroster outlet 11e, respectively, in the
second side of the air flow passage 11. These outlet switching
dampers 13b, 13c and 13d are configured to move together by a
linkage (not shown). Here, when the outlet switching dampers 13b,
13c and 13d open the foot outlet 1c, close the vent outlet 11d and
slightly open the defroster outlet 11e, most of the air flowing
through the air flow passage 11 blows out of the foot outlet 11c
and the remaining air blows out of the defroster outlet 11e. This
mode is referred to as "foot mode." Meanwhile, when the outlet
switching dampers 13b, 13c and 13d close the foot outlet 11c and
the defroster outlet 11e, and open the vent outlet 11d, all the air
flowing through the air flow passage 11 blows out of the vent
outlet 11d. This mode is referred to as "vent mode." In addition,
when the outlet switching dampers 13b, 13c and 13d open the foot
outlet 11c and the vent outlet 11d, and close the defroster outlet
11e, the air flowing through the air flow passage 11 blows out of
the foot outlet 11c and the vent outlet 11d. This mode is referred
to as "bi-level mode." Moreover, when the outlet switching dampers
13b, 13c and 13d close the foot outlet 11c and the vent outlet 11d,
and open the defroster outlet 11e, the air flowing through the air
flow passage 11 blows out of the defroster outlet 11e. This mode is
referred to as "defroster mode." Furthermore, when the outlet
switching dampers 13b, 13c and 13d close the vent outlet 11d and
open the foot outlet 11c and the defroster outlet 11e, the air
flowing through the air flow passage 11 blows out of the foot
outlet 11c and the defroster outlet 11e. This mode is referred to
as "defroster-foot mode." Here, in the bi-level mode, the air flow
passage 11, the foot outlet 11c, the vent outlet 11d, and a heat
exchanger and a radiator which will be described later, are
arranged and configured such that the temperature of the air
blowing out of the foot outlet 11c is higher than the temperature
of the air blowing out of the vent outlet 11d.
[0060] A heat exchanger 14 is provided in the air flow passage 11
in the downstream of the air flow from the indoor fan 12. The heat
exchanger 14 is configured to cool and dehumidify the air flowing
through the air flow passage 11. In addition, a radiator 15 is
provided in the air flow passage 11 in the downstream of the air
flow from the heat exchanger 14. The radiator 15 is configured to
heat the air flowing through the air flow passage 11. The heat
exchanger 14 and the radiator 15 are heat exchangers, each of which
is constituted by fins and tubes and which is configured to perform
a heat exchange between the refrigerant flowing therethrough and
the air flowing through the air flow passage 11.
[0061] An air mix damper 16 is provided between the heat exchanger
14 and the radiator 15 in the air flow passage 11 and is configured
to control the percentage of the air to be heated, which is flowing
through the air flow passage 11. When the air mix damper 16 is
disposed in the air flow passage 11 in the k of the radiator 15,
the percentage of the air subjected to a heat exchange in the
radiator 15 is reduced. Meanwhile, when the air mix damper 16 is
moved to a position other than the radiator 15 in the air flow
passage 11, the percentage of the air subjected to a heat exchange
is increased. In the air flow passage 11, when the air mix damper
16 closes the upstream side of the radiator 15 and opens the
portion other than the radiator 15, the opening is 0%, and, on the
other hand, when the air mix damper 16 opens the upstream side of
the radiator 15 and closes the portion other than the radiator 15,
the opening is 100%.
[0062] The refrigerant circuit 20 includes: the heat exchanger 14;
the radiator 15; a compressor 21 configured to compress a
refrigerant; an outdoor heat exchanger 22 configured to perform a
heat exchange between the refrigerant and the outdoor air; [0063] a
receiver tank 23 configured to accumulate liquid refrigerant
discharged from the outdoor heat exchanger; a supercooling radiator
24 as an outdoor radiator configured to supercool the liquid
refrigerant discharged from the receiver tank 23; [0064] an
internal heat exchanger 25 configured to perform a heat exchange
between the refrigerant discharged from the supercooling radiator
24 and the refrigerant discharged from the heat exchanger 14; a
first control valve 26 including an expansion part configured to
decompress the refrigerant flowing into the outdoor heat exchanger
22 during the heating operation and the first heating and
dehumidifying operation, and a condensing pressure regulating part
configured to regulate the condensing pressure of the refrigerant
in the radiator 15 during the cooling and dehumidifying operation;
a second control valve 27 configured to regulate the evaporating
pressure of the refrigerant in the heat exchanger 14; first to
fourth solenoid valves 28a, 28b, 28c and 28d; first to fourth check
valves 29a, 29b, 29c and 29d; an expansion valve 30; and an
accumulator 31 configured to separate liquid refrigerant from
refrigerant vapor to prevent the liquid refrigerant from being
sucked into the compressor 21. These components are connected to
each other by a copper pipe or an aluminum pipe.
[0065] To be more specific, input side of the radiator 15 into
which the refrigerant flows is connected to the delivery side of
the compressor 21 from which the refrigerant is discharged to form
the refrigerant flow passage 20a. In addition, the input side of
the first control valve 26 into which the refrigerant flows is
connected to the output side of the radiator 15 from which the
refrigerant is discharged, thereby to form the refrigerant flow
passage 20b. A first connection port of the outdoor heat exchanger
22 is connected to the output side of the expansion part and the
condensing pressure regulating part of the first control valve 26
from which the refrigerant is discharged, thereby to form the
refrigerant flow passage 20c. The input side of the receiver tank
23 into which the refrigerant flows is connected to a second
connection port of the outdoor heat exchanger 22, thereby to form
the refrigerant flow passage 20d. In the refrigerant flow passage
20d, the first solenoid valve 28a and the first check valve 29a in
the order from the outdoor heat exchanger 22 side. The input side
of the supercooling radiator 24 into which the refrigerant flows is
connected to the output side of the receiver tank 23 from which the
refrigerant is discharged, thereby to form the refrigerant flow
passage 20e. The input side of the internal heat exchanger 25 into
which a high-pressure refrigerant flows is connected to the output
side of the supercooling radiator 24 from which the refrigerant is
discharged, thereby to form the refrigerant flow passage 20f. The
input side of the heat exchanger 14 into which the refrigerant
flows is connected to the output side of the internal heat
exchanger 25 from which the high-pressure refrigerant is
discharged, thereby to from the refrigerant flow passage 20g. The
expansion valve 30 is provided in the refrigerant flow passage 20g.
The input side of the internal heat exchanger 25 into which a
low-pressure refrigerant flows is connected to the output side of
the heat exchanger 14 from which the refrigerant is discharged,
thereby to form the refrigerant flow passage 20h. The second
control valve 27 is provided in the refrigerant flow passage 20h.
The suction side of the compressor 21 into which the refrigerant is
sucked is connected to the output side of the internal heat
exchanger 25 from which the refrigerant is discharged, thereby to
form the refrigerant flow passage 20i. The third check valve 29c
and the accumulator 31 are provided in the refrigerant flow passage
20i in the order from the internal heat exchanger 25 side. The part
of the refrigerant flow passage 20d between the first check valve
29a and the receiver tank 23 is connected to the refrigerant flow
passage 20b, thereby to form the refrigerant flow passage 20j. The
second solenoid valve 28b and the second check valve 29b are
provided in the refrigerant flow passage 20j in the order from the
refrigerant flow passage 20b side. The part of the refrigerant flow
passage 20i between the third check valve 29c and the accumulator
31 is connected to a third connection port of the outdoor heat
exchanger 22, thereby to form the refrigerant flow passage 20k. The
third solenoid valve 28c is provided in the refrigerant flow
passage 20k. The refrigerant flow passage 20c is connected to the
refrigerant flow passage 20a, thereby to form the refrigerant flow
passage 201 as a defrosting circuit. The fourth solenoid valve 28d
and the fourth check valve 29d are provided in the refrigerant flow
passage 201 in the order from the refrigerant flow passage 20a.
[0066] The compressor 21, the outdoor heat exchanger 22, the
receiver tank 23 and the supercooling radiator 24 are disposed
outside the vehicle interior. The outdoor heat exchanger 22
includes an outdoor fan 32 configured to perform a heat exchange
between the outdoor air and the refrigerant while the vehicle
stops.
[0067] As shown in FIG. 2, the outdoor heat exchanger 22 is formed
integrally with the receiver tank 23, the supercooling radiator 24,
the first control valve 26, the first solenoid valve 28a, the
second solenoid valve 28b, the third solenoid valve 28c, the first
check valve 29a and the second check valve 29b to realize an
outdoor heat exchanger unit U.
[0068] The outdoor heat exchanger 22 and the supercooling radiator
24 include: a pair of upper and lower headers 22a extending in the
width direction; a plurality of flat tubes 22b provided apart from
each other and connecting between the headers 22a; and wavy fins
22c provided between each of the flat tubes 22b. The outdoor heat
exchanger 22 is provided in one side of the width direction of the
pair of headers 22a meanwhile the supercooling radiator 24 is
provided in the other side of the width direction of the pair of
headers 22a.
[0069] Each of the header 22a is made of a cylindrical member
having closed both ends. The inside of each of the headers 22a is
partitioned in the width direction by a plurality of partition
members 22d. By this means, a refrigerant flow path that extends in
the width direction, zigzagging up and down, is formed in the
outdoor heat exchanger 22. The refrigerant flow passage 20c is
connected to the lower header 22a at a position in one space of the
lower header 22a for the outdoor heat exchanger 22. The refrigerant
flow passage 20d and the refrigerant flow passage 20k are connected
to the lower header 22a at respective positions in another space
for the outdoor heat exchanger 22. Moreover, the refrigerant flow
passage 20e is connected to the lower header 22a at a position in
the space for the supercooling radiator 24. Meanwhile, the
refrigerant flow passage 20f is connected to the upper header 22a
at a position in the space for the supercooling radiator 24.
[0070] The receiver tank 23 is made of a cylindrical member
extending in the vertical direction and having closed both ends.
The refrigerant flow passages 20d and 20e are connected to the
lower end of the receiver tank 23. Surplus refrigerant in the
refrigerant circuit 20 is accumulated in the receiver tank 23.
[0071] The internal heat exchanger 25 is, for example, a
double-pipe heat exchanger, and is configured to allow the
refrigerant flowing through the refrigerant flow passage 20f to
flow into the inner pipe and to allow the refrigerant flowing
through the refrigerant flow passage 20h to flow into the outer
pipe, and therefore to perform a heat exchange between these
refrigerants.
[0072] In the first control valve 26, the refrigerant flow channel
to the expansion part and the refrigerant flow channel to the
condensing pressure regulating part are provided for one
refrigerant inlet. In addition, in the control valve 26, one
refrigerant outlet is provided for both the refrigerant flow
channel to the expansion part and the refrigerant flow channel to
the condensing pressure regulating part. A valve element for
regulating a valve opening is provided in each of the refrigerant
flow channel to the expansion part and the refrigerant flow channel
to the condensing pressure regulating part. The expansion part of
the first control valve 26 has a function as an electronic
expansion valve, and the condensing pressure regulating part has a
function as a solenoid valve. The first control valve 26 can
regulate the valve opening between when the valve opening of each
of the expansion part and the condensing pressure regulating part
is zero and when it is full. Also, as shown in FIG. 3, the first
control valve 26 can regulate the opening area of the refrigerant
flow channel between when the expansion part and the condensing
pressure regulating part are completely closed and when they are
fully open. FIG. 3 shows the relationship between a valve opening
signal and an opening area, with the horizontal axis for the valve
opening signal and the vertical axis for the opening size
equivalent to the opening area of the refrigerant flow channel.
FIG. 3A shows the relationship between the valve opening signal and
the opening size equivalent to the opening area of the refrigerant
flow channel in the expansion part side. FIG. 3B shows the
relationship between the valve opening signal and the opening size
equivalent to the opening area of the refrigerant flow channel in
the condensing pressure regulating part side. FIG. 3C shows the
relationship between the valve opening signal and the opening size
equivalent to the opening area of the refrigerant flow channel in
the combination of the expansion part side and the condensing
pressure regulating part side.
[0073] The second control valve 27 is configured to allow its
opening to be regulated step by step or optionally. The second
control valve 27 is configured to regulate an amount of the
refrigerant flowing through the refrigerant flow passage 20h by
regulating the valve opening, and consequently to regulate the
evaporating pressure of the refrigerant in the heat exchanger
14.
[0074] The expansion valve 30 is a temperature expansion valve
having the adjustable opening according to the temperature of the
refrigerant discharged from the heat exchanger 14. As a temperature
expansion valve, for example, a box type temperature valve
including a refrigerant outlet channel that allows the refrigerant
flowing out of the heat exchanger to flow through, a
temperature-sensitive rod that detects the temperature of the
refrigerant flowing out of the refrigerant outlet channel, and a
diaphragm to move the valve element, which are integrally
formed.
[0075] As shown in FIG. 1, the vehicle air conditioning apparatus
further includes a controller 40 configured to control the number
of rotations of the compressor 21, the valve opening of the first
control valve 26, the valve opening of the second control valve 27,
and the opening and closing of each of the first to fourth solenoid
valves 28a, 28b, 28c and 28d.
[0076] The compressor 21, the first control valve 26, the second
control valve 27, and the first to fourth solenoid valves 28a, 28b,
28c and 28d are connected to the output side of the controller 40.
Meanwhile, a high-pressure refrigerant temperature sensor 41
configured to detect temperature Thp1 of a high-pressure
refrigerant flowing through the refrigerant flow passage 20b; a
high-pressure refrigerant pressure sensor 42 configured to detect
pressure Php1 of the high-pressure refrigerant flowing through the
refrigerant flow passage 20b; a low-pressure refrigerant
temperature sensor 43 configured to detect temperature Thp2 of a
low-pressure refrigerant flowing through the refrigerant flow
passage 20k; a low-pressure refrigerant pressure sensor 44
configured to detect pressure Php2 of the low-pressure refrigerant
flowing through the refrigerant flow passage 20k; an intake air
temperature sensor 45 configured to detect temperature T of air
flowing through the air flow passage 11 upstream from the heat
exchanger 14; a cooled air temperature sensor 46 configured to
detect temperature Tc flowing downstream from the heat exchanger
14; a sucked refrigerant temperature sensor 47 configured to detect
the temperature of the refrigerant flowing through the refrigerant
flow passage 20i that is sucked into the compressor 21; a sucked
refrigerant pressure sensor 48 configured to detect the pressure of
the refrigerant flowing through the refrigerant flow passage 20i
that is sucked into the compressor 21; a discharged refrigerant
pressure sensor 49 configured to detect the pressure of the
refrigerant flowing through the refrigerant flow passage 20a that
is discharged from the compressor 21; an input refrigerant
temperature sensor 50 configured to detect the temperature of the
refrigerant flowing through the refrigerant flow passage 20a that
flows into the radiator 15; and an input refrigerant pressure
sensor 51 configured to detect the pressure of the refrigerant
flowing through the refrigerant flow passage 20a that flows into
the radiator 15; and a pressure sensor 52 configured to detect the
pressure of the refrigerant flowing through the refrigerant flow
passage 20f, are connected to the input side of the controller 40.
Here, the high-pressure refrigerant temperature sensor 41 and the
high-pressure refrigerant pressure sensor 42 do not necessarily
need to be separated, but may be integrally formed. Also, the
sucked refrigerant temperature sensor 47 and the sucked refrigerant
pressure sensor 48 do not necessarily need to be separated, but
maybe integrally formed. Moreover, the input refrigerant
temperature sensor 50 and the input refrigerant pressure sensor 51
do not necessarily need to be separated, but may be integrally
formed.
[0077] The vehicle air conditioning apparatus having the
above-described configuration performs cooling operation, cooling
and dehumidifying operation, heating operation, first heating and
dehumidifying operation as heating and dehumidifying operation,
second heating and dehumidifying operation as internal heating and
dehumidifying operation, and first defrosting operation. Now, each
operation will be explained.
[0078] During the cooling operation and the cooling and
dehumidifying operation, in the refrigerant circuit 20, the
refrigerant flow channel to the expansion part is closed while the
refrigerant flow channel to the condensing pressure regulating part
is opened in the first control valve 26; the first solenoid valve
28a is opened; the second, third and fourth solenoid valves 28b,
28c and 28d are closed; and compressor 21 is operated. By this
means, as shown in FIG. 4, the refrigerant discharged from the
compressor 21 flows through in this order: the refrigerant flow
passage 20a; the radiator 15; the refrigerant flow passage 20b; the
condensing pressure regulating part of the first control valve 26;
the refrigerant flow passage 20c; the outdoor heat exchanger 22;
refrigerant flow passage 20d; the receiver tank 23; the refrigerant
flow passage 20e; the supercooling radiator 24; the refrigerant
flow passage 20f; the high-pressure side of the internal heat
exchanger 25; the refrigerant flow passage 20g; the heat exchanger
14; the refrigerant flow passage 20h; the low-pressure side of the
internal heat exchanger 25; and the refrigerant flow passage 20i,
and is sucked into the compressor 21. During the cooling operation,
the refrigerant flowing through the refrigerant circuit 20 releases
the heat in the outdoor heat exchanger 22 and absorbs the heat in
the heat exchanger 14. During the cooling and dehumidifying
operation, when the air mix damper 16 is opened as shown by the
dashed-dotted line of FIG. 4, the refrigerant flowing through the
refrigerant circuit 20 releases the heat also in the radiator
15.
[0079] In this case, in the air conditioning unit 10 during the
cooling operation, the indoor fan 12 is operated to flow the air
through the air flow passage 11, and the air is subjected to a heat
exchange with the refrigerant in the heat exchanger 14 and cooled.
The temperature of the cooling air becomes target air-blowing
temperature TAO of the air to blowout of the outlets 11c, 11d and
11e to the vehicle interior in order to set the temperature of the
vehicle interior to the target preset temperature Tset.
[0080] The target air-blowing temperature TAO is calculated based
on the preset temperature Tset, and environmental conditions
including the outdoor air temperature Tam, the indoor air
temperature Tr, and an amount of insolation Ts.
[0081] Meanwhile, in the air conditioning unit 10 during the
cooling and dehumidifying operation, the indoor fan 12 is operated
to flow the air through the air flow passage 11, and the air is
subjected to a heat exchange with the refrigerant which absorbs the
heat in the heat exchanger 14, and therefore is cooled and
dehumidified. The air having been dehumidified in the heat
exchanger 14 is subjected to a heat exchange with the refrigerant
which releases the heat in the radiator 15, and therefore heated.
As a result, the air at the target air-blowing temperature TAO
blows to the vehicle interior.
[0082] During the cooling and dehumidifying operation, the opening
of the condensing pressure regulating part of the first control
valve 26 is adjusted to regulate the condensing pressure of the
refrigerant in the radiator 15. That is, it is possible to control
the quantity of heat release in the radiator 15 by regulating the
condensing pressure of the refrigerant in the radiator 15. To be
more specific, the condensing pressure of the refrigerant in the
radiator 15 is decreased by increasing the opening of the
condensing pressure regulating part of the first control valve 26,
and, on the other hand, is increased by decreasing the opening. By
this means, the quantity of heat release in the radiator 15 is
decreased by decreasing the condensing pressure but is increased by
increasing the condensing pressure.
[0083] During the cooling operation and the cooling and
dehumidifying operation, the refrigerant having passed through the
outdoor heat exchanger 22 flows into the supercooling radiator 24
via the receiver tank 23. Therefore, the liquid refrigerant flowing
into the supercooling radiator 24 is subjected to a heat exchange
with the outdoor air and becomes in a supercooling state.
[0084] During the heating operation, in the refrigerant circuit 20,
the refrigerant flow channel to the expansion part is opened while
the refrigerant flow channel to the condensing pressure regulating
part is closed in the first control valve 26; the third solenoid
valve 28c is opened; the first, second, and fourth solenoid valves
28a, 28b and 28d are closed; and the compressor 21 is operated. By
this means, as shown in FIG. 5, the refrigerant discharged from the
compressor 21 flows through in this order: the refrigerant flow
passage 20a; the radiator 15; the refrigerant flow passages 20b;
the expansion part of the first control valve 26; the refrigerant
flow passages 20c; the outdoor heat exchanger 22; and the
refrigerant flow passages 22k and 20i, and is sucked into the
compressor 21. The refrigerant flowing through the refrigerant
circuit 20 releases the heat in the radiator 15 and absorbs the
heat in the outdoor heat exchanger 22.
[0085] In this case, in the air conditioning unit 10, the indoor
fan 12 is operated to flow the air through the air flow passage 11,
and the flowing air is not subjected to a heat exchange with the
refrigerant in the heat exchanger 14, but is subjected to a heat
exchange with the refrigerant in the radiator 15 and therefore is
heated. As a result, the air at the target air-blowing temperature
TAO blows to the vehicle interior.
[0086] During the first heating and dehumidifying operation, in the
refrigerant circuit 20, the refrigerant flow channel to the
expansion part is opened while the refrigerant flow channel to the
condensing pressure regulating part is closed in the first control
valve 26; the second and third solenoid valves 28b and 28c are
opened; the first and fourth solenoid valves 28a and 28d are
closed; and the compressor 21 is operated. By this means, as shown
in FIG. 6, the refrigerant discharged from the compressor 21 flows
through in this order: the refrigerant flow passage 20a; the
radiator 15; and the refrigerant flow passage 20b. Part of the
refrigerant flowing through the refrigerant flow passage 20b flows
through in this order: the expansion part of the first control
valve 26; the refrigerant flow passage 20c; the outdoor heat
exchanger 22; and the refrigerant flow passages 20k and 20i, and is
sucked into the compressor 21. Meanwhile, the remaining refrigerant
flowing through the refrigerant flow passage 20b flows through in
this order: the refrigerant flow passages 20j and 20d; the receiver
tank 23; the refrigerant flow passage 20e; the supercooling
radiator 24, the refrigerant flow passage 20f; the high-pressure
side of the internal heat exchanger 25; the refrigerant flow
passage 20g; the heat exchanger 14; the refrigerant flow passage
20h; the low-pressure side of the internal heat exchanger 25; and
the refrigerant flow passage 20i, and is sucked into the compressor
21. The refrigerant flowing through the refrigerant circuit 20
releases the heat in the radiator 15 and absorbs the heat in the
heat exchanger 14 and the outdoor heat exchanger 22.
[0087] In this case, in the air conditioning unit 10, the indoor
fan 12 is operated to flow the air through the air flow passage 11,
and the flowing air is subjected to a heat exchange with the
refrigerant in the heat exchanger 14, and therefore is cooled and
dehumidified. Part of the air having been dehumidified in the heat
exchanger 14 is subjected to a heat exchange with the refrigerant
in the radiator 15 and heated. As a result, the air at the target
air-blowing temperature TAO blows into the vehicle interior.
[0088] In addition, the evaporating temperature of the refrigerant
in the heat exchanger 14 is controlled by regulating the opening of
the second control valve 27. That is, when the opening of the
second control valve 27 is decreased, the evaporating temperature
of the refrigerant in the heat exchanger 14 increases. On the other
hand, when the opening of the second control valve 27 is increased,
the evaporating temperature decreases.
[0089] During the second heating and dehumidifying operation, in
the refrigerant circuit 20, both the refrigerant flow channel to
the expansion part and the refrigerant flow channel to the
condensing pressure regulating part are closed in the first control
valve 26; the second solenoid valve 28b is opened; the first, third
and fourth solenoid valves 28a, 28c and 28d are closed; and the
compressor 21 is operated. By this means, as shown in FIG. 7, the
refrigerant discharged from the compressor 21 flows through in this
order: the refrigerant flow passage 20a; the radiator 15; the
refrigerant flow passages 20b, 20j and 20d; the receiver tank 23;
the refrigerant flow passages 20e; the supercooling radiator 24;
the refrigerant flow passages 20f; the high-pressure side of the
internal heat exchanger 25; the refrigerant flow passages 20g; the
heat exchanger 14; the refrigerant flow passages 20h; the
low-pressure side of the internal heat exchanger 25; and the
refrigerant flow passages 20i, and is sucked into the compressor
21. The refrigerant flowing through the refrigerant circuit 20
releases the heat in the radiator 15 and absorbs the heat in the
heat exchanger 14.
[0090] In this case, in the air conditioning unit 10, the indoor
fan 12 is operated to flow the air through the air flow passage 11,
and the flowing air is subjected to a heat exchange with the
refrigerant in the heat exchanger 14, and therefore is cooled and
dehumidified in the same way as in the first heating and
dehumidifying operation. Part of the air dehumidified in the heat
exchanger 14 is subjected to a heat exchange with the refrigerant
in the radiator 15, and therefore heated. As a result, the air at
the target air-blowing temperature TAO blows to the vehicle
interior. Here, the air flowing into the air flow passage 11 may be
the outdoor air or the indoor air.
[0091] During the defrosting operation, in the refrigerant circuit
20, the refrigerant flow channel to the expansion part is opened
while the refrigerant flow channel to the condensing pressure
regulating part is closed in the first control valve 26; the third
and fourth solenoid valves 28c and 28d are opened while the first
and second solenoid valves 28a and 28b are closed; and the
compressor 21 is operated. By this means, as shown in FIG. 8, part
of the refrigerant discharged from the compressor 21 flows through
in this order: the refrigerant flow passage 20a; the radiator 15;
the refrigerant flow passage 20b; the expansion part of the first
control valve 26; and the refrigerant flow passage 20c, and is
sucked into the compressor 21. Meanwhile, the remaining refrigerant
discharged from the compressor 21 flows through the refrigerant
flow passages 201 and 20c, and flows into the outdoor heat
exchanger 22. The refrigerant discharged from the outdoor heat
exchanger 22 flows through the refrigerant flow passages 20k and
20i, and is sucked into the compressor 21. The refrigerant flowing
through the refrigerant circuit 20 releases the heat in the
radiator 15, and at this time, absorbs the heat in the outdoor heat
exchanger 22.
[0092] In this case, in the air conditioning unit 10, the indoor
fan 12 is operated to flow the air through the air flow passage 11.
The flowing air is not subjected to a heat exchange with the
refrigerant in the heat exchanger 14, but is subjected to a heat
exchange with the refrigerant which releases the heat in the
radiator 15, and therefore is heated and then blows to the vehicle
interior.
[0093] In the above-described air conditioning operations, the
opening and closing of each of the first control valve 26, the
second control valve 27, and the first to fourth solenoid valves is
switched as shown in the table of FIG. 9.
[0094] While an automatic switch is turned on, the operation is
switched among the cooling operation, the cooling and dehumidifying
operation, the heating operation, the first heating and
dehumidifying operation, the second heating and dehumidifying
operation and the defrosting operation, based on environmental
conditions including the outdoor air temperature Tam, the indoor
air temperature Tr, the outdoor air humidity, the indoor air
humidity Th, the amount of insolation Ts and so forth.
[0095] In addition, the mode of the outlets 11c, 11d and 11e are
switched by the outlet switching dampers 13b, 13c and 13d. The
opening of the air mix damper 16 is controlled such that the
temperature of the air blowing out of the outlets 11c, 11d and 11e
is the target air-blowing temperature TAO.
[0096] In each operation, switching the operation among the foot
mode, the vent mode and the bi-level mode of each of the outlets
11c, 11d and 11e is performed according to the target air-blowing
temperature TAO. To be more specific, when the target air-blowing
temperature TAO is high, for example, 40 degrees Celsius, the mode
is set to the foot mode. Meanwhile, when the target air-blowing
temperature TAO is low, for example, lower than 25 degrees Celsius,
the mode is set to the vent mode. Moreover, when the target
air-blowing temperature TAO is the temperature between the
temperature for the foot mode and the temperature for the vent
mode, the mode is set to the bi-level mode.
[0097] When each of the outlets 11c, 11d and 11e is set to the
bi-level mode, the controller performs a determination process for
second heating and dehumidifying operation to determine whether or
not to perform the second heating and dehumidifying operation. Now,
the operation of the controller 40 in this process will be
explained with reference to the flowchart of FIG. 10.
[0098] (Step 1)
[0099] In step 1, the CPU determines whether or not each of the
outlets 11c, 11d and 11e is set to the bi-level mode. When
determining that the outlets are set to the bi-level mode, the CPU
moves the step to step S2. On the other hand, when determining that
the outlets are not set to the bi-level mode, the CPU ends the
determination process for second heating and dehumidifying
operation.
[0100] (Step S2)
[0101] In the case of determining that the bi-level mode is set in
the step S1, the CPU determines whether or not temperature T
detected by the intake air temperature sensor 45 is first
predetermined temperature T1 (e.g. 10 to 15 degrees Celsius) or
higher in the step S2. When determining that the temperature T
detected by the intake air temperature sensor 45 is the first
predetermined temperature T1 or higher, the CPU moves the step to
step S3. On the other hand, when determining that the temperature T
detected by the intake air temperature 45 is lower than the first
predetermined temperature T1, the CPU moves the step to step
S5.
[0102] (Step S3)
[0103] In the case of determining that the temperature T detected
by the intake air temperature sensor 45 is the first predetermined
temperature T1 or higher in the step 2, the CPU determines whether
or not the temperature T detected by the intake air temperature
sensor 45 is second predetermined temperature T2 (e.g. 20 to 25
degrees Celsius) or higher in the step S3. When determining that
the temperature detected by the intake air temperature sensor 45 is
the second predetermined temperature T2 or higher, the CPU moves
the step to the step S5. On the other hand, when determining that
the temperature T detected by the intake air temperature sensor 45
is lower than the second predetermined temperature (T1<T<T2),
the CPU moves the step to step S4.
[0104] (Step S4)
[0105] In the case of determining that the temperature detected by
the intake air temperature sensor 45 is lower than the second
predetermined temperature T2 in the step S3, the CPU starts the
second heating and dehumidifying operation and ends the
determination process for second heating and dehumidifying
operation in the step S4.
[0106] (Step S5)
[0107] In the case of determining that the temperature T detected
by the intake air temperature sensor 45 is lower than the first
predetermined temperature in the step S2, or in the case of
determining that the temperature T is the second predetermined
temperature T2 or higher in the step S3, the CPU ends the second
heating and dehumidifying operation in the step 5, and ends the
determination process for second heating and dehumidifying
operation.
[0108] whether or not to perform the second heating and
dehumidifying operation may be determined not only based on the
temperature T of the air flowing upstream the heat exchanger 14,
but also the temperature of the outdoor air.
[0109] In addition, during the cooling and dehumidifying operation,
or the first heating and dehumidifying operation, when each of the
outlets 11c, 11d and 11e is set to the bi-level mode, a process for
switching to second heating and dehumidifying operation is
performed to switch the operation to the second heating and
dehumidifying operation, based on the temperature of the air after
a heat exchange with the refrigerant in the heat exchanger 14. Now,
the operation of the controller 40 in this process will be
explained with reference to the flowchart of FIG. 11.
[0110] (Step S11)
[0111] In step S11, the CPU determines whether or not the cooling
and dehumidifying operation is being performed. When determining
that the cooling and dehumidifying operation is being performed,
the CPU moves the step to step 12. On the other hand, when
determining that the heating and dehumidifying operation is not
being performed, the CPU moves the step to step S13.
[0112] (Step S12)
[0113] In the case of determining that the cooling and
dehumidifying operation is being performed in the step S11, the CPU
determines whether or not temperature Tc detected by the cooled air
temperature sensor 46 is a third predetermined temperature Tc1 or
lower in the step 12. When determining that the temperature Tc
detected by the cooled air temperature sensor 46 is the third
predetermined temperature Tc1 or lower, the CPU moves the step to
step 15. On the other hand, determining that the temperature Tc is
higher than the third predetermined temperature Tc1, the CPU ends
the process for switching to second heating and dehumidifying
operation.
[0114] (Step 13)
[0115] In the case of determining that the cooling and
dehumidifying operation is not being performed in the step S11, the
CPU determines whether or not the first heating and dehumidifying
operation is being performed. When determining that the first
heating and dehumidifying operation is being performed, the CPU
moves the step to step S14. On the other hand, when determining
that the first heating and dehumidifying operation is not being
performed, the CPU ends the process for switching to second heating
and dehumidifying operation.
[0116] (Step 14)
[0117] In the case of determining that the first heating and
dehumidifying operation is being performed in the step S13, the CPU
determines whether or not the temperature Tc detected by the cooled
air temperature sensor 46 is a fourth predetermined temperature Tc2
or higher. When determining that the temperature Tc detected by the
cooled air temperature sensor 36 is the fourth predetermined
temperature Tc2 or higher, the CPU moves the step to step S15. On
the other hand, when determining that the temperature is lower than
the fourth predetermined temperature Tc2, the CPU ends the process
for switching to second heating and dehumidifying operation.
[0118] (Step S15)
[0119] In the case of determining that the temperature Tc detected
by the cooled air temperature sensor 46 is the third predetermined
temperature Tc1 or lower in the step S12, or in the case of
determining that the temperature Tc detected by the cooled air
temperature sensor 46 is the fourth predetermined temperature Tc2
or higher in the step S14, the CPU switches the operation to the
second heating and dehumidifying operation in the step S15, and
ends the process for switching to second heating and dehumidifying
operation.
[0120] The operation may be switched to the second heating and
dehumidifying operation not only based on the temperature Tc of the
air flowing downstream from the heat exchanger 14, but also based
on a predicted value of the air flowing downstream from the
radiator 15.
[0121] In addition, during the second heating and dehumidifying
operation, the temperature of the air flowing downstream from the
radiator 15 is regulated by controlling the number of rotations of
the compressor 21. Moreover, during the second heating and
dehumidifying operation, since the outlets 11c, 11c and 11e are set
to the bi-level mode, the temperature of the air supplied to the
vehicle interior is controlled to be the target air-blowing
temperature TAO, by adjusting the opening of the air mix damper 16
within a predetermined range. In this case, the number of rotations
of the compressor 21 is controlled, based on any of, or a
combination of any of: the pressure of the high-pressure side of
the refrigerant circuit 20; the temperature of the high-pressure
side of the refrigerant circuit 20; the temperature of the air
flowing through the air flow passage 11; and the temperature of the
air flowing downstream from the heat exchanger 14.
[0122] In addition, regardless of whether or not the outlets 11c,
11d and 11e are set to the bi-level mode, the controller 40
performs an process for controlling operation switching to switch
the operation among the first heating and dehumidifying operation,
the second heating and dehumidifying operation and the cooling
operation or the cooling and dehumidifying operation. Now, the
operation of the controller 40 in this process will be explained
with reference to the flowchart of FIG. 12.
[0123] (Step S21)
[0124] In step S21, the CPU determines whether or not the first
heating and dehumidifying operation is being performed. When
determining that the first heating and dehumidifying operation is
being performed, the CPU moves the step to step S22. On the other
hand, when determining that the first heating and dehumidifying
operation is not being performed, the CPU moves the step to step
S24.
[0125] (Step S22)
[0126] In the case of determining that the first heating and
dehumidifying operation is being performed in the step S21, the CPU
determines whether or not the difference (Tc-TEO) between the
temperature Tc detected by the cooled air temperature sensor 46 and
the target temperature TEO of the air flowing downstream from the
heat exchanger 14 is greater than a predetermined value. When
determining that the difference (Tc-TEO) is greater than the
predetermined value, the CPU moves the step to step S27. On the
other hand, when determining that the difference is the
predetermined value or smaller, the CPU moves the step to step
S23.
[0127] (Step S23)
[0128] In the case of determining that the difference (Tc-TEO)
between the detected temperature Tc and the target temperature TEO
is the predetermined value or smaller in the step S22; or, in step
26 described later, when determining that the difference (TCO-TH)
between target temperature TCO of the air flowing downstream from
the radiator 15 and estimated temperature TH of the air flowing
downstream from the radiator 15 is greater than a predetermined
value, or determining that the difference (TEO-Tc) between the
target temperature TEO of the air flowing downstream from the heat
exchanger 14 and the temperature Tc detected by the cooled air
temperature sensor 46 is greater than the predetermined value, the
CPU performs the first heating and dehumidifying operation in the
step S23, and ends the process for controlling operation
switching.
[0129] (Step S24)
[0130] In the case of determining that the first heating and
dehumidifying operation is not being performed in the step S21, the
CPU determines whether or not the second heating and dehumidifying
operation is being performed in step S24. When determining that the
second heating and dehumidifying operation is being performed, the
CPU moves the step to step S25. On the other hand, when determining
that the second heating and dehumidifying operation is not being
performed, the CPU moves the step to step S28.
[0131] (Step S25)
[0132] In the case of determining that the second heating and
dehumidifying operation is being performed in the step S24, the CPU
determines whether or not the difference (Tc-TEO) between the
temperature Tc detected by the cooled air temperature sensor 46 and
the target temperature TEO of the air flowing downstream from the
heat exchanger 14 is greater than a predetermined value. When
determining that the difference is greater than the predetermined
value, the CPU moves the step to step S30. On the other hand, when
determining that the difference is the predetermined value or
smaller, the CPU moves the step to the step S26.
[0133] (Step S26)
[0134] In the case of determining that the difference (Tc-TEO)
between the temperature Tc detected by the cooled air temperature
46 and the target temperature TEO of the air flowing downstream
from the heat exchanger 14 is the predetermined value or smaller in
the step 25, the CPU determines whether or not the difference
(TCO-TH) between the target temperature TCO of the air flowing
downstream from the radiator 15 and the estimated temperature TH of
the air flowing downstream from the radiator 15 is greater than a
predetermined value, or, determines whether or not the difference
(TEO-Tc) between the target temperature TEO of the air flowing
downstream from the heat exchanger 14 and the temperature Tc
detected by the cooled air temperature sensor 46 is greater than a
predetermined value. When determining that the difference is
greater than the predetermined value, the CPU moves the step to the
step S23. On the other hand, when determining that the difference
is the predetermined value or smaller, the CPU moves the step to
the step S27.
[0135] (Step S27)
[0136] In the case of determining that the difference (Tc-TEO)
between the detected temperature Tc and the target temperature TEO
is greater than the predetermined value in the S22;in the case of
determining that the difference (TEO-Tc) between the target
temperature TEO of the air flowing downstream from the heat
exchanger 14 and the temperature Tc detected by the cooled air
temperature 46 is the predetermined value or smaller in the step
26; or when determining that the difference (TCO-TH) between the
target temperature TCO of the radiator 15 and the estimated
temperature TH is greater than a predetermined value in step S29
described later, the CPU performs the second heating and
dehumidifying operation in the step S27 and ends the process for
controlling operation switching.
[0137] (Step S28)
[0138] In the case of determining that the second heating and
dehumidifying operation is not being performed in the step S24, the
CPU determines whether or not the cooling operation or the cooling
and dehumidifying operation is being performed in the step S28.
When determining that the cooling operation or the cooling and
dehumidifying operation is being performed, the CPU moves the step
to the step S29. On the other hand, when determining that the
cooling operation or the cooling and dehumidifying operation is not
being performed, the CPU ends the process for controlling operation
switching.
[0139] (Step S29)
[0140] In the case of determining that the cooling operation or the
cooling and dehumidifying operation is being performed in the step
S28, the CPU determines whether or not the difference (TCO-TH)
between the target temperature TCO of the radiator 15 and the
estimated temperature TH of the air flowing downstream from the
radiator 15 is greater than a predetermined value in the step 29.
When determining that the difference is greater than the
predetermined value, the CPU moves the step to the step S27. On the
other hand, when determining that the difference is the
predetermined value or smaller, the CPU moves the step to the step
S30.
[0141] (Step S30)
[0142] In the case of determining that the difference (Tc-TEO)
between the detected temperature Tc and the target temperature TEO
is greater than the predetermined value in the step S25, or, in the
case of determining that the difference (TCO-TH) between the target
temperature TCO and the estimated temperature TH is the
predetermined temperature or smaller in the step S29, the CPU
performs the cooling operation or the cooling and dehumidifying
operation in the step S30 and ends the process for controlling
operation switching.
[0143] Here, the predetermined value of the difference between the
temperature Tc detected by the cooled air temperature sensor 46 and
the target temperature TEO of the heat exchanger 14, and the
predetermined value of the difference between the target
temperature TCO of the radiator 15 and the estimated temperature TH
of the air downstream from the radiator 15 are both set within the
range of, for example, 2 to 3 degrees Celsius. In addition, with
the present example, the predetermined value is calculated based on
the temperature Tc detected by the cooled air temperature sensor
46, which is the temperature of the air flowing downstream from the
heat exchanger 14. However, the predetermined value may be
calculated based on an actual measured value of the surface
temperature (between the fins) of the heat exchanger 14. Moreover,
with the present example, the predetermined value is calculated
based on the estimated temperature TH of the air flowing downstream
from the radiator 15. However, the predetermined value may be
calculated based on an actual measured value of the air flowing
downstream from the radiator 15.
[0144] In this way, with the vehicle air conditioning apparatus
according to the present example, during the cooling operation and
the cooling and dehumidifying operation, the refrigerant passes
through the outdoor heat exchanger 22 and passes through the
supercooling radiator 24 and then absorbs the heat in the heat
exchanger 14. Meanwhile, during the heating operation, the
refrigerant passes through the outdoor heat exchanger 22 and then
is sucked into the compressor 21 without passing through the
supercooling radiator 24. Moreover, during the first heating and
dehumidifying operation and the second heating and dehumidifying
operation, the refrigerant passes through the radiator 15 and
passes through the supercooling radiator 24, and then absorbs the
heat in the heat exchanger 14. By this means, the refrigerant
becomes in a supercooling state in the supercooling radiator 24 and
then flows through the heat exchanger 14, and therefore it is
possible to improve the efficiency of the air conditioning
operation. Meanwhile, the refrigerant not supposed to flow through
the heat exchanger 14 is sucked into the compressor 21 without
passing through the supercooling radiator 24. Therefore, it is
possible to reduce pressure loss, and consequently improve the
efficiency of the air conditioning operation.
[0145] Moreover, the receiver tank 23 which can accumulate the
liquid refrigerant is provided upstream from the supercooling
radiator 24 in the refrigerant flow direction. By this means, it is
possible to accumulate surplus refrigerant in the receiver tank 23
during the cooling operation, the cooling and dehumidifying
operation, the first heating and dehumidifying operation and the
second heating and dehumidifying operation, and therefore to adjust
the amount of the refrigerant circulating in the refrigerant
circuit 20 to a proper amount.
[0146] Moreover, the refrigerant flow passage 201 is provided,
which allows the refrigerant discharged from the compressor 21 to
directly flow into the outdoor heat exchanger 22. By this means, it
is possible to flow the refrigerant at a high temperature into the
outdoor heat exchanger 22, and therefore to shorten the defrosting
time when a frost is formed on the outdoor heat exchanger 22.
[0147] Furthermore, the refrigerant flows into the outdoor heat
exchanger 22 from one end of the refrigerant flow path formed in
the outdoor heat exchanger 22 and is discharged from the other end.
By this means, the circuit configuration of the refrigerant circuit
20 becomes simple, and therefore it is possible to reduce the
manufacturing cost.
[0148] Furthermore, the outdoor heat exchanger unit U is realized
by integrally form the outdoor heat exchanger 22, the receiver tank
23, the supercooling radiator 24, the first control valve 26, the
first solenoid valve 28a, the second solenoid valve 28b, the third
solenoid valve 28c, the first check valve 29a and the second check
valve 29b. By this means, it is possible to install the outdoor
heat exchanger unit U as one component, and therefore to reduce the
number of steps for the installation.
[0149] Moreover, the first control valve 26 including the expansion
part having the function as an electronic solenoid valve and the
condensing pressure regulating part having the function as a
solenoid valve which are integrally formed is provided in the
refrigerant circuit 20, and the input side into which the
refrigerant flows and the output side from which the refrigerant is
discharged are formed as connection ports, respectively. By this
means, two components having the different functions are installed
as one component, and therefore it is possible to reduce the number
of steps for the installation.
[0150] Furthermore, when the outlets 11c, 11d and 11e are set to
the bi-level mode, the second heating and dehumidifying operation
is started and stopped, based on the temperature T detected by the
intake air temperature sensor 45. By this means, it is possible to
efficiently perform the second heating and dehumidifying operation
under the condition with a low air conditioning load, and therefore
to reduce the energy consumption.
[0151] Furthermore, during the cooling and dehumidifying operation
or the first heating and dehumidifying operation, the operation is
switched to the second heating and dehumidifying operation, based
on the temperature Tc detected by the cooled air temperature sensor
46. By this means, it is possible to perform the second heating and
dehumidifying operation under the condition with a low air
conditioning load, and therefore to reduce the energy
consumption.
[0152] Furthermore, the temperature of the air flowing downstream
from the radiator 15 is regulated by controlling the number of
rotations of the compressor 21, and the temperature of the air
supplied to the vehicle interior is controlled to be the target
air-blowing temperature TAO by regulating the opening of the air
mix damper 16. By this means, it is possible to optimize the
temperature of the air supplied to the vehicle interior, and
therefore to optimize the temperature-humidity environment of the
vehicle interior.
[0153] FIGS. 13 and 14 show Example 2 of the present invention.
Here, the same components are assigned the same reference numerals
as in the above-described example.
[0154] As shown in FIG. 13, the refrigerant flow passage 20e is
connected to the refrigerant flow passage 20f, thereby to form a
refrigerant flow passage 20m in the refrigerant circuit 20 of the
vehicle air conditioning apparatus. A fifth solenoid valve 28e is
provided in the refrigerant flow passage 20m. In addition, a sixth
solenoid valve 28f is provided downstream from the connection part
of the refrigerant flow passage 20e with the refrigerant flow
passage 20m. Moreover, a fifth check valve 29e is provided in the
upstream side of the connection part of the refrigerant flow
passage 20f with the refrigerant flow passage 20m.
[0155] In the vehicle air conditioning apparatus having the
above-described configuration, the opening and closing of each of
the first control valve 26, the second control valve 27, the first
to sixth solenoid valves 28a, 28b, 28c, 28d, 28e and 28f is
switched during the cooling operation, the cooling and
dehumidifying operation, the heating operation, the first heating
and dehumidifying operation, the second heating and dehumidifying
operation and the defrosting operation, as shown in the table of
FIG. 14.
[0156] During the first heating and dehumidifying operation and the
second heating and dehumidifying operation, the refrigerant having
passed through the refrigerant flow passage 20d flows into the
receiver tank 23 and then, flows into the heat exchanger 14 without
flowing into the supercooling radiator 24.
[0157] In this way, with the vehicle air conditioning apparatus
according to the present example, the refrigerant becomes in a
supercooling state in the supercooling radiator 24, and then flows
through the heat exchanger 14 during the cooling operation and the
cooling and dehumidifying operation. Therefore, it is possible to
improve the efficiency of the air conditioning operation.
Meanwhile, the refrigerant not supposed to flow through the heat
exchanger 14 is sucked into the compressor 21 without passing
through the supercooling radiator 24. Therefore, it is possible to
reduce pressure loss, and consequently improve the efficiency of
the air conditioning operation.
[0158] In addition, during the first heating and dehumidifying
operation and the second heating and dehumidifying operation, the
refrigerant discharged from the radiator 15 flows through the
receiver tank 23 without flowing into the supercooling radiator 24,
and then flows into the heat exchanger 14. By this means, it is
possible to reduce the pressure loss during the first heating and
dehumidifying operation and the second heating and dehumidifying
operation. In addition, it is possible to accumulate surplus
refrigerant in the receiver tank 23, and therefore to adjust the
amount of the refrigerant circulating in the refrigerant circuit 20
to a proper amount.
[0159] FIGS. 15 and 16 show Example 3 of the present invention.
Here, the same components are assigned the same reference numerals
as in the above-described example.
[0160] As shown in FIG. 15, the refrigerant flow passage 20m and
the third check valve 29c are provided in the refrigerant circuit
20 of the vehicle air conditioning apparatus, like Example 2. A
three-way solenoid valve 28g is provided at the connection point
between the refrigerant flow passage 20e and the refrigerant flow
passage 20m.
[0161] In the vehicle air conditioning apparatus having the
above-described configuration, the opening and closing of each of
the first control valve 26, the second control valve 27, the first
to forth solenoid valves 28a, 28b, 28c and 28d, and the three-way
solenoid valve 28g is switched during the cooling operation, the
cooling and dehumidifying operation, the heating operation, the
first heating and dehumidifying operation, the second heating and
dehumidifying operation and the defrosting operation, as shown in
the table of FIG. 16.
[0162] During the first heating and dehumidifying operation and the
second heating and dehumidifying operation, the refrigerant having
passed through the refrigerant flow passage 20d flows into the
receiver tank 23 and then, flows into the heat exchanger 14 without
passing through the supercooling radiator 24.
[0163] In this way, with the vehicle air conditioning apparatus
according to the present example, the refrigerant becomes in a
supercooling state in the supercooling radiator 24, and then flows
through the heat exchanger 14 during the cooling operation and the
cooling and dehumidifying operation. Therefore, it is possible to
improve the efficiency of the air conditioning operation.
Meanwhile, the refrigerant not supposed to flow through the heat
exchanger 14 is sucked into the compressor 21 without passing
through the supercooling radiator 24. Therefore, it is possible to
reduce pressure loss, and consequently improve the efficiency of
the air conditioning operation.
[0164] In addition, during the first heating and dehumidifying
operation and the second heating and dehumidifying operation, the
refrigerant discharged from the radiator 15 flows through the
receiver tank 23 without flowing into the supercooling radiator 24,
and then flows into the heat exchanger 14. By this means, it is
possible to reduce the pressure loss during the first heating and
dehumidifying operation and the second heating and dehumidifying
operation. In addition, it is possible to accumulate surplus
refrigerant in the receiver tank 23, and therefore to adjust the
amount of the refrigerant circulating in the refrigerant circuit 20
to a proper amount.
[0165] FIGS. 17 and 18 show Example 4 of the present invention.
Here, the same components are assigned the same reference numerals
as in the above-described example.
[0166] As shown in FIG. 17, this vehicle air conditioning apparatus
includes a refrigerant flow passage 20n that connects the
refrigerant flow passage 20b to the refrigerant flow passage 20f
upstream from the internal heat exchanger 25, instead of the
refrigerant flow passage 20j described in Example 1. In the
refrigerant flow passage 20n, the second solenoid valve 28b, the
receiver tank 23a and the second check valve 29b are provided in
the order from the upstream side.
[0167] In the vehicle air conditioning apparatus having the
above-described configuration, the opening and closing of each of
the first control valve 26, the second control valve 27, the first
to forth solenoid valves 28a, 28b, 28c and 28d is switched during
the cooling operation, the cooling and dehumidifying operation, the
heating operation, the first heating and dehumidifying operation,
the second heating and dehumidifying operation and the defrosting
operation as shown in the table of FIG. 18.
[0168] During the first heating and dehumidifying operation and the
second heating and dehumidifying operation, the refrigerant having
passed through the refrigerant flow passage 20n flows into the
receiver tank 23 and then, flows into the heat exchanger 14 without
flowing into the supercooling radiator 24.
[0169] In this way, with the vehicle air conditioning apparatus
according to the present example, the refrigerant becomes in a
supercooling state in the supercooling radiator 24, and then flows
into the heat exchanger 14 during the cooling operation and the
cooling and dehumidifying operation. Therefore, it is possible to
improve the efficiency of the air conditioning operation.
Meanwhile, the refrigerant not supposed to flow through the heat
exchanger 14 is sucked into the compressor 21 without passing
through the supercooling radiator 24. Therefore, it is possible to
reduce pressure loss, and consequently improve the efficiency of
the air conditioning operation.
[0170] In addition, during the first heating and dehumidifying
operation and the second heating and dehumidifying operation, the
refrigerant discharged from the radiator 15 flows through the
receiver tank 23 without flowing into the supercooling radiator 24,
and then flows into the heat exchanger 14. By this means, it is
possible to reduce the pressure loss during the first heating and
dehumidifying operation and the second heating and dehumidifying
operation. In addition, it is possible to accumulate surplus
refrigerant in the receiver tank 23, and therefore to adjust the
amount of the refrigerant circulating in the refrigerant circuit 20
to a proper amount.
[0171] FIGS. 19 to 29 show Example 5 of the present invention.
Here, the same components are assigned the same reference numerals
as in the above-described example.
[0172] As shown in FIG. 19, a refrigerant circuit 60 is provided in
the vehicle air conditioning apparatus.
[0173] To be more specific, the input side of the radiator 15 into
which the refrigerant flows is connected to the output side of the
compressor 21 from which the refrigerant is discharged to provide a
refrigerant flow passage 60a. Meanwhile, the input side of the
first control valve 26 into which the refrigerant flows is
connected to the output side of the radiator 15 from which the
refrigerant is discharged to provide a refrigerant flow passage
60b. A first connection port of the outdoor heat exchanger 22 is
connected to the output side of the condensing pressure regulating
part of the first control valve 26 from which the refrigerant is
discharged to provide a refrigerant flow passage 60c. A second
connection port of the outdoor heat exchanger 22 is connected to
the output side of the expansion port of the first control valve 26
from which the refrigerant is discharged to provide a refrigerant
flow passage 60d. The first check valve 29a is provided in the
refrigerant flow passage 60d. The input side of the receiver tank
23 into which the refrigerant flows is connected to the third
connection port of the outdoor heat exchanger 22 to provide a
refrigerant flow passage 60e. In the refrigerant flow passage 60e,
the first solenoid valve 28a and the second check valve 29b are
provided in the order from the outdoor heat exchanger 22 side. The
input side of the supercooling radiator 24 into which the
refrigerant flows is connected to the output side of the receiver
tank 23 from which the refrigerant is discharged to provide a
refrigerant flow passage 60f. The input side of the internal heat
exchanger 25 into which the high-pressure refrigerant flows is
connected to the output side of the supercooling radiator 24 from
which the refrigerant is discharged to provide a refrigerant flow
passage 60g. The input side of the heat exchanger 14 into which the
refrigerant flows is connected to the output side of the internal
heat exchanger 25 form which the high-pressure refrigerant is
discharged to provide a refrigerant flow passage 60h. The expansion
valve 30 is provided in the refrigerant flow passage 60h. The input
side of the internal heat exchanger 25 into which a low-pressure
refrigerant flows is connected to the output side of the heat
exchanger 14 from which the refrigerant is discharged to provide a
refrigerant flow passage 60i. The second control valve 27 is
provided in the refrigerant flow passage 60i. The suction side of
the compressor 21 into which the refrigerant is sucked is connected
to the output side of the internal heat exchanger 25 from which the
low-pressure refrigerant is discharged to provide a refrigerant
flow passage 60j. In the refrigerant flow passage 60j, the fifth
check valve 29e and the accumulator 31 are provided in the order
from the internal heat exchanger 25 side. Part of the refrigerant
flow passage 60e between the first check valve 29a and the receiver
tank 23 is connected to the refrigerant flow passage 60b to provide
a refrigerant flow passage 60k. In the refrigerant flow passage
60k, the second solenoid valve 28b and the third check valve 29c
are provided in the order from the refrigerant flow passage 60b
side. In addition, in the refrigerant flow passage 60c, part of the
refrigerant flow passage 60j between the internal heat exchanger 25
and the accumulator 31 to provide a refrigerant flow passage 601.
The third solenoid valve 28c is provided in the refrigerant flow
passage 601. The refrigerant flow passage 60a is connected to the
refrigerant flow passage 60d downstream from the first check valve
29a in the refrigerant flow direction to provide a refrigerant flow
passage 60m. In the refrigerant flow passage 60m, the fourth
solenoid valve 28d and the fourth check valve 29d are provided in
the order from the refrigerant flow passage 60a side.
[0174] As shown in FIG. 20, the outdoor heat exchanger 22 is
integrally formed with the receiver tank 23, the supercooling
radiator 24, the first control valve 26, the first solenoid valve
28a, the second solenoid valve 28b, the third solenoid valve 28c,
the first check valve 29a, the second check valve 29b, the third
check valve 29C and the fourth check valve 29d, and therefore to
realize the outdoor heat exchanger unit U.
[0175] The partition members 22d partition each header 22a of the
outdoor heat exchanger 22 such that the cross section of the
refrigerant path decreases from the connection port of the
refrigerant flow passage 60c to the connection port of the
refrigerant flow passage 60e. By this means, when the outdoor heat
exchanger 22 functions as a radiator, the refrigerant entering from
the refrigerant flow passage 60c passes through the refrigerant
flow path whose cross section gradually decreases, so that it is
possible to reliably condense the refrigerant vapor. Meanwhile,
when the outdoor heat exchanger 22 functions as an evaporator, the
refrigerant entering from the refrigerant flow passage 60d passes
through the refrigerant flow path whose cross section gradually
increases. This allows the refrigerant with a greater volume due to
the evaporation to smoothly flow through, so that it is possible to
reduce pressure loss.
[0176] The first control valve 26 includes the refrigerant flow
channel to the expansion part and the refrigerant flow channel to
the condensing pressure regulating part, that are provided for one
refrigerant inlet. A valve element is provided in each refrigerant
flow channel to control its opening. As shown in FIG. 21A, the
first control valve 26 includes the expansion part as an electronic
expansion valve 26a, and the condensing pressure regulating part as
a solenoid valve 26b. As seen from the graph showing each valve
opening in FIG. 21A, the first control valve 26 can control the
valve opening of the electronic expansion valve 26a between the
completely closed state and the fully open state. In addition, the
opening and closing of the electronic expansion valve 26b can be
switched by turning on and off.
[0177] As another configuration of the first control valve 26, as
shown in FIG. 21B, the expansion part and the condensing pressure
regulating part may be a small diameter valve 26c and a large
diameter valve 26d, respectively. Each of them has an optionally
controllable opening. In this case, the opening of each of the
small diameter valve 26c and the large diameter valve 26d is
optionally controllable between the completely closed state and the
fully open state.
[0178] Moreover, as another configuration of the first control
valve 26, as shown in FIG. 21C, the first control valve 26 may
include a small diameter valve 26e and a large diameter valve 26f
each having the opening that steeply increases near the fully open.
By this means, it is possible to increase the amount of the flowing
refrigerant during the defrosting operation, and therefore to
shorten the time required for the defrosting operation. As shown in
FIG. 22, the small diameter valve 26a includes a valve body 26e1, a
valve seat 26e2 that can move upward and downward with respect to
the valve body 26e1, and a needle-like valve element 26e3 that can
move upward and downward with respect to the valve seat 26e2. As
shown in FIG. 22A, the small diameter valve 26e closes the
refrigerant flow channel to the valve body 26e1. Meanwhile, as
shown in FIG. 22B, the valve element 26e3 moves upward to open the
refrigerant flow channel, and therefore to allow the refrigerant to
flow through. Moreover, as shown in FIG. 22C, the valve element
26e3 moves upward to move the valve seat 26e2 upward, and therefore
to separate between the valve seat 26e2 and the valve body 26e1. By
this means, it is possible to increase an amount of the refrigerant
flowing through.
[0179] Furthermore, as shown in FIG. 23, another configuration of
the first control valve 26 is possible where the first check valve
29a is integrally formed.
[0180] The vehicle air conditioning apparatus having the
above-described configuration performs cooling operation, cooling
and dehumidifying operation, heating operation, first heating and
dehumidifying operation, second heating and dehumidifying
operation, and defrosting operation. Now, each operation will be
explained.
[0181] During the cooling and dehumidifying operation, in the
refrigerant circuit 60, the refrigerant flow channel to the
expansion part is closed while the refrigerant flow channel to the
condensing pressure regulating part is opened in the first control
valve 26; the first solenoid valve 28a is opened; the second, third
and fourth solenoid valves 28b, 28c and 28d are closed; and
compressor 21 is operated. By this means, as shown in FIG. 24, the
refrigerant discharged from the compressor 21 flows through in this
order: the refrigerant flow passage 60a; the radiator 15; the
refrigerant flow passage 60b; the condensing pressure regulating
part of the first control valve 26; the refrigerant flow passage
60c; the outdoor heat exchanger 22; refrigerant flow passage 60e;
the receiver tank 23; the refrigerant flow passage 60f; the
supercooling radiator 24; the high-pressure side of the internal
heat exchanger 25; the refrigerant flow passage 60h; the heat
exchanger 14; the refrigerant flow passage 60i; the low-pressure
side of the internal heat exchanger 25; and the refrigerant flow
passage 60j, and is sucked into the compressor 21.
[0182] During the cooling operation and the cooling and
dehumidifying operation, the refrigerant having passed through the
outdoor heat exchanger 22 flows into the supercooling radiator 24
via the receiver tank 23. Therefore, the liquid refrigerant flowing
into the supercooling radiator 24 is subjected to a heat exchange
with the outdoor air and becomes in a supercooling state.
[0183] During the heating operation, in the refrigerant circuit 60,
the refrigerant flow channel to the expansion part is opened while
the refrigerant flow channel to the condensing pressure regulating
part is closed in the first control valve 26; the third solenoid
valve 28c is opened; the first, second, and fourth solenoid valves
28a, 28b and 28d are closed; and the compressor 21 is operated. By
this means, as shown in FIG. 25, the refrigerant discharged from
the compressor 21 flows through in this order: the refrigerant flow
passage 60a; the radiator 15; the refrigerant flow passage 60b; the
expansion part of the first control valve 26; the refrigerant flow
passage 60d; the outdoor heat exchanger 22; and the refrigerant
flow passages 60c and 601, and is sucked into the compressor
21.
[0184] During the first heating and dehumidifying operation, in the
refrigerant circuit 60, the refrigerant flow channel to the
expansion part is opened while the refrigerant flow channel to the
condensing pressure regulating part is closed in the first control
valve 26; the second and third solenoid valves 28b and 28c are
opened; the first and fourth solenoid valves 28a and 28d are
closed; and the compressor 21 is operated. By this means, as shown
in FIG. 26, the refrigerant discharged from the compressor 21 flows
through in this order: the refrigerant flow passage 60a; the
radiator 15; and the refrigerant flow passage 60b. Part of the
refrigerant flowing through the refrigerant flow passage 60b flows
through in this order: the expansion part of the first control
valve 26; the refrigerant flow passage 60d; the outdoor heat
exchanger 22; and the refrigerant flow passages 60c and 601, and is
sucked into the compressor 21. Meanwhile, the remaining refrigerant
flowing through the refrigerant flow passage 60b flows through in
this order: the refrigerant flow passages 60k and 60c; the receiver
tank 23; the refrigerant flow passage 60f; the supercooling
radiator 24, the refrigerant flow passage 60g; the high-pressure
side of the internal heat exchanger 25; the refrigerant flow
passage 60h; the heat exchanger 14; the refrigerant flow passage
60i; the low-pressure side of the internal heat exchanger 25; and
the refrigerant flow passage 60i, and is sucked into the compressor
21.
[0185] During the second heating and dehumidifying operation, in
the refrigerant circuit 60, both the refrigerant flow channel to
the expansion part and the refrigerant flow channel to the
condensing pressure regulating part are closed in the first control
valve 26; the second solenoid valve 28b is opened; the first, third
and fourth solenoid valves 28a, 28c and 28d are closed; and the
compressor 21 is operated. By this means, as shown in FIG. 27, the
refrigerant discharged from the compressor 21 flows through in this
order: the refrigerant flow passage 60a; the radiator 15; the
refrigerant flow passages 60b, 60k and 60e; the receiver tank 23;
the refrigerant flow passage 60f; the supercooling radiator 24; the
refrigerant flow passage 60g; the high-pressure side of the
internal heat exchanger 25; the refrigerant flow passage 60h; the
heat exchanger 14; the refrigerant flow passage 60i; the
low-pressure side of the internal heat exchanger 25; and the
refrigerant flow passages 60j, and is sucked into the compressor
21.
[0186] During the defrosting operation, in the refrigerant circuit
60, the refrigerant flow channel to the expansion part is opened
while the refrigerant flow channel to the condensing pressure
regulating part is closed in the first control valve 26; the third
and fourth solenoid valves 28c and 28d are opened; and the first
and second solenoid valves 28a and 28b are closed, and the
compressor 21 is operated. By this means, as shown in FIG. 28, part
of the refrigerant discharged from the compressor 21 flows through
in this order: the refrigerant flow passage 60a; the radiator 15;
the refrigerant flow passage 60b; the expansion part of the first
control valve 26; and the refrigerant flow passage 30d, and is
sucked into the compressor 21. Meanwhile, the remaining refrigerant
discharged from the compressor 21 flows through the refrigerant
flow passages 60m and 60d, and flows into the outdoor heat
exchanger 22. The refrigerant discharged from the outdoor heat
exchanger 22 flows through the refrigerant flow passages 60c and
60j, and is sucked into the compressor 21.
[0187] In the above-described air conditioning operations, the
opening and closing of each of the first control valve 26, the
second control valve 27, and the first to fourth solenoid valves
28a, 28b, 28c and 28d is switched as shown in the table of FIG.
29.
[0188] As described above, with the vehicle air conditioning
apparatus according to the present example, the refrigerant becomes
in a supercooling state in the supercooling radiator 24, and then
flows into the heat exchanger 14 during the cooling operation and
the cooling and dehumidifying operation. Therefore, it is possible
to improve the efficiency of the air conditioning operation.
Meanwhile, the refrigerant not supposed to flow through the heat
exchanger 14 is sucked into the compressor 21 without passing
through the supercooling radiator 24. Therefore, it is possible to
reduce pressure loss, and consequently improve the efficiency of
the air conditioning operation.
[0189] In addition, the refrigerant flow path is formed in the
outdoor heat exchanger 22. For heat release, the refrigerant flows
into the first end of the refrigerant flow path, releases the heat,
and is discharged from the second end. Meanwhile, for heat
absorption, the refrigerant flows into the second end of the
refrigerant flow path, absorbs the heat, and is discharged from the
first end. By this means, in both the case of condensing the
refrigerant and the case of evaporating the refrigerant in the
outdoor heat exchanger 22, it is possible to realize the
refrigerant flow path that allows the refrigerant to flow through
in an optimal condition. Therefore, it is possible to improve the
refrigerant condensing performance of the outdoor heat exchanger
22. Moreover, it is possible to reduce the pressure loss in
evaporating the refrigerant in the outdoor heat exchanger 22.
[0190] FIGS. 30 and 31 show Example 6 of the present invention.
Here, the same components are assigned the same reference numerals
as in the above-described example.
[0191] As shown in FIG. 30, the vehicle air conditioning apparatus
includes a refrigerant flow passage 60n configured to connect the
refrigerant flow passage 60b to the refrigerant flow passage 60g
upstream from the internal heat exchanger 25, instead of the
refrigerant flow passage 60k described in Example 5. In the
refrigerant flow passage 60n, the second solenoid valve 28b, the
receiver tank 23a and the second check valve 29b are provided in
the order from the upstream side.
[0192] In the vehicle air conditioning apparatus having the
above-described configuration, the opening and closing of each of
the first control valve 26, the second control valve 27, the first
to forth solenoid valves 28a, 28b, 28c and 28d is switched during
the cooling operation, the cooling and dehumidifying operation, the
heating operation, the first heating and dehumidifying operation,
the second heating and dehumidifying operation and the defrosting
operation, as shown in the table of FIG. 31.
[0193] During the first heating and dehumidifying operation and the
second heating and dehumidifying operation, the refrigerant having
passed through the refrigerant flow passage 60n flows into the
receiver tank 23 and then, flows into the heat exchanger 14 without
passing through the supercooling radiator 24.
[0194] As described above, with the vehicle air conditioning
apparatus according to the present example, the refrigerant becomes
in a supercooling state in the supercooling radiator 24, and then
flows into the heat exchanger 14 during the cooling operation and
the cooling and dehumidifying operation. Therefore, it is possible
to improve the efficiency of the air conditioning operation.
Meanwhile, the refrigerant not supposed to flow through the heat
exchanger 14 is sucked into the compressor 21 without passing
through the supercooling radiator 24. Therefore, it is possible to
reduce pressure loss, and consequently improve the efficiency of
the air conditioning operation.
[0195] In addition, during the first heating and dehumidifying
operation and the second heating and dehumidifying operation, the
refrigerant discharged from the radiator 15 flows through the
receiver tank 23 and then flows into the heat exchanger 14 without
passing through the supercooling radiator 24. By this means, it is
possible to reduce the pressure loss also during the first heating
and dehumidifying operation and the second heating and
dehumidifying operation. Moreover, it is possible to accumulate the
surplus refrigerant in a receiver tank 23a, and therefore to adjust
the amount of the refrigerant circulating in the refrigerant
circuit 20 to a proper amount.
[0196] Here, with the above-described examples, a configuration has
been explained where the internal heat exchanger is provided in the
refrigerant circuit 20 or 60, it is by no means limiting. It is
possible to produce the same effect in the example without the
internal heat exchanger 25.
[0197] In addition, with the examples, the configuration of the
first control valve 26 has been described where the expansion part
having a function as an electronic expansion valve and the
condensing pressure regulating part having a function as a solenoid
valve are integrally formed. However, it is by no means limiting.
Another configuration is possible where, for example, the first
control valve 26 includes a three-way valve that can switch the
refrigerant outlet from one to the other and an expansion valve
provided in one refrigerant outlet.
[0198] Moreover, although with the examples, the expansion valve 30
has been described as a temperature expansion valve, it is by no
means limiting, and an electronic expansion valve is
applicable.
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