U.S. patent application number 13/317872 was filed with the patent office on 2012-05-03 for air conditioner for vehicle.
This patent application is currently assigned to DENSO CORPORATION. Invention is credited to Yuji Kawazoe, Manabu Maeda, Koji Ota.
Application Number | 20120102974 13/317872 |
Document ID | / |
Family ID | 45995152 |
Filed Date | 2012-05-03 |
United States Patent
Application |
20120102974 |
Kind Code |
A1 |
Kawazoe; Yuji ; et
al. |
May 3, 2012 |
Air conditioner for vehicle
Abstract
In a vehicle air conditioner, a heating heat exchanger is
disposed in an air passage of a casing to heat air to be blown
toward a vehicle compartment by performing heat exchange between
air and a heating fluid, a heat radiation portion is disposed to
radiate heat to the heating fluid before being heat-exchanged in
the heating heat exchanger, a heat absorption portion is disposed
to absorb heat from the heating fluid after being heat-exchanged in
the heating heat exchanger, and a Peltier element is disposed
between the heat radiation portion and the heat absorption portion
to pump heat from the heat absorption portion to the heat radiation
portion. Furthermore, the heat radiation portion is disposed in the
air passage of the casing, in which the heating heat exchanger is
disposed. Thus, heat discharged from the Peltier element can be
effectively used.
Inventors: |
Kawazoe; Yuji; (Kariya-city,
JP) ; Ota; Koji; (Kariya-city, JP) ; Maeda;
Manabu; (Nagoya-city, JP) |
Assignee: |
DENSO CORPORATION
Kariya-city
JP
|
Family ID: |
45995152 |
Appl. No.: |
13/317872 |
Filed: |
October 31, 2011 |
Current U.S.
Class: |
62/3.61 |
Current CPC
Class: |
F28D 1/0478 20130101;
B60H 1/00035 20130101; F28D 1/0417 20130101; F28D 1/0435 20130101;
B60H 1/00478 20130101; H01L 35/30 20130101; F25B 21/02 20130101;
B60H 2001/00128 20130101; F28D 1/05366 20130101 |
Class at
Publication: |
62/3.61 |
International
Class: |
F25B 21/02 20060101
F25B021/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 3, 2010 |
JP |
2010-246948 |
Claims
1. An air conditioner for a vehicle, comprising: a casing defining
an air passage through which air flows into a vehicle compartment;
a heating heat exchanger disposed in the air passage of the casing
to heat air to be blown toward the vehicle compartment by
performing heat exchange between air and a heating fluid; a heat
radiation portion disposed to radiate heat to the heating fluid
before being heat-exchanged in the heating heat exchanger; a heat
absorption portion disposed to absorb heat from the heating fluid
after being heat-exchanged in the heating heat exchanger; and a
Peltier element disposed between the heat radiation portion and the
heat absorption portion to pump heat from the heat absorption
portion to the heat radiation portion, wherein the heat radiation
portion is disposed in the air passage of the casing, in which the
heating heat exchanger is disposed.
2. The air conditioner for a vehicle according to claim 1, wherein
the heat radiation portion, the Peltier element and the heat
absorption portion are formed integrally with the heating heat
exchanger.
3. The air conditioner for a vehicle according to claim 1, wherein
the heating heat exchanger includes a passage forming member
defining a heating fluid passage in which the heating fluid flows,
the heat radiation portion is configured by a heating-fluid inlet
side portion of the passage forming member, the heat absorption
portion is configured by a heating-fluid outlet side portion of the
passage forming member, and the Peltier element is arranged between
the heating-fluid inlet side portion and the heating-fluid outlet
side portion of the passage forming member.
4. The air conditioner for a vehicle according to claim 3, wherein
the heat radiation portion configured by the heating-fluid inlet
side portion of the passage forming member is a part of a
heat-exchanging portion in which the heating fluid is
heat-exchanged with air.
5. The air conditioner for a vehicle according to claim 3, wherein
the passage forming member is formed in a serpentine shape.
6. The air conditioner for a vehicle according to claim 3, wherein
the heating heat exchanger includes a fin member that is arranged
on an outer surface of the passage forming member in the heat
exchanging portion to facilitate heat exchange between air and the
heating fluid, the fin member is arranged with different fin
pitches at a heating-fluid upstream side of the passage forming
member and at a heating-fluid downstream side of the passage
forming member, and the fin pitch of the fin member at the
heating-fluid upstream side of the passage forming member is larger
than the fin pitch of the fin member at the heating-fluid
downstream side of the passage forming member.
7. The air conditioner for a vehicle according to claim 3, wherein
the heating-fluid inlet side portion used as the heat radiation
portion and the heating-fluid outlet side portion used as the heat
absorption portion have therein a passage height that is smaller
than 1 mm.
8. The air conditioner for a vehicle according to claim 1, wherein
the heating heat exchanger includes a first heating heat exchanger,
and a second heating heat exchanger disposed to heat air after
passing through the first heating heat exchanger, and the heat
radiation portion, the Peltier element and the heat absorption
portion are provided at least at the second heating heat exchanger,
in the first and second heating heat exchangers.
9. The air conditioner for a vehicle according to claim 8, wherein
the heat radiation portion and the heat absorption portion are
configured such that the heating fluid flowing out of the first
heating heat exchanger is joined to the heating fluid flowing in
the heat absorption portion or the heating fluid before flowing
into the heat absorption portion.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based on Japanese Patent Application No.
2010-246948 filed on Nov. 3, 2010, the contents of which are
incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to an air conditioner for a
vehicle.
BACKGROUND
[0003] Conventionally, a vehicle air conditioner is provided with a
heating heat exchanger that heats air to be blown into a vehicle
compartment by using engine coolant as a heat source, and an
auxiliary heater for performing supplementary heating operation,
for example, in Patent Document 1 (JP 2007-278624A corresponding to
U.S. 2008/0041071A1) or Patent Document 2 (JP 2008-126820A).
[0004] However, in a case where the engine coolant is simply heated
by the auxiliary heater, the heat quantity without being
heat-exchanged with air in the heating heat exchanger may be
radiated from the surface of an engine coolant system, and the
heated quantity may be uselessly consumed.
[0005] This problem is also caused when a fluid other than the
engine coolant is used as the heat source.
SUMMARY
[0006] The present invention is made in view of the above matters,
and it is an object of the present invention to provide an air
conditioner for a vehicle, in which a heat amount discharged from a
Peltier element can be effectively used.
[0007] It is another object of the present invention to provide an
air conditioner for a vehicle, in which a heat amount discharged
from a Peltier element can be effectively used while mounting
performance of the Peltier element to the vehicle can be
improved.
[0008] According to an aspect of the present invention, an air
conditioner for a vehicle includes a casing defining an air passage
through which air flows into a vehicle compartment, a heating heat
exchanger disposed in the air passage of the casing to heat air to
be blown toward the vehicle compartment by performing heat exchange
between air and a heating fluid, a heat radiation portion disposed
to radiate heat to the heating fluid before being heat-exchanged in
the heating heat exchanger, a heat absorption portion disposed to
absorb heat from the heating fluid after being heat-exchanged in
the heating heat exchanger, and a Peltier element disposed between
the heat radiation portion and the heat absorption portion to pump
heat from the heat absorption portion to the heat radiation
portion. In the vehicle air conditioner, because the heat radiation
portion is disposed in the air passage of the casing, in which the
heating heat exchanger is disposed, heat discharged from the
Peltier element can be effectively used for heating air to be blown
into the vehicle compartment.
[0009] Furthermore, by mounting the casing to the vehicle, it is
possible for the heat radiation portion, heat absorption portion
and the Peltier element to be mounted to the vehicle, thereby
improving the mounting performance in the vehicle. For example, the
heat radiation portion, the Peltier element and the heat absorption
portion may be formed integrally with the heating heat
exchanger.
[0010] The heating heat exchanger may include a passage forming
member defining a heating fluid passage in which the heating fluid
flows. In this case, the heat radiation portion may be configured
by a heating-fluid inlet side portion of the passage forming
member, the heat absorption portion may be configured by a
heating-fluid outlet side portion of the passage forming member,
and the Peltier element may be arranged between the heating-fluid
inlet side portion and the heating-fluid outlet side portion of the
passage forming member. Furthermore, the heat radiation portion
configured by the heating-fluid inlet side portion of the passage
forming member may be a part of a heat-exchanging portion in which
the heating fluid is heat-exchanged with air.
[0011] The heating heat exchanger may include a first heating heat
exchanger, and a second heating heat exchanger disposed to heat air
after passing through the first heating heat exchanger. In this
case, the heat radiation portion, the Peltier element and the heat
absorption portion may be provided at least at the second heating
heat exchanger, in the first and second heating heat exchangers.
Furthermore, the heat radiation portion and the heat absorption
portion may be configured such that the heating fluid flowing out
of the first heating heat exchanger is joined to the heating fluid
flowing in the heat absorption portion or the heating fluid before
flowing into the heat absorption portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Other objects, features and advantages of the present
invention will become more apparent from the following description
made with reference to the accompanying drawings, in which like
parts are designated by like reference numbers and in which:
[0013] FIG. 1 is a schematic diagram showing an air conditioner for
a vehicle according to a first embodiment of the present
invention;
[0014] FIG. 2 is a perspective view showing a first heater core and
a second heater core in the air conditioner shown in FIG. 1;
[0015] FIG. 3 is a schematic diagram showing a configuration of the
second heater core according to the first embodiment;
[0016] FIG. 4 is a cross-sectional view taken along the line IV-IV
of FIG. 3;
[0017] FIG. 5 is a block diagram showing an air conditioning
controller in the air conditioner, according to the first
embodiment;
[0018] FIG. 6 is a flowchart showing a control process performed by
the air conditioning controller shown in FIG. 5;
[0019] FIG. 7 is a flow diagram showing a detail control at step S4
of FIG. 6;
[0020] FIG. 8 is a graph showing the relationship between a passage
height of a tube in the second heater core and a heat transmission
efficiency, according to the first embodiment;
[0021] FIG. 9 is a schematic diagram showing a configuration of a
second heater core according to a second embodiment of the present
invention;
[0022] FIG. 10 is a schematic diagram showing a configuration of a
second heater core according to a third embodiment of the present
invention;
[0023] FIG. 11 is a schematic diagram showing a configuration of a
second heater core according to a fourth embodiment of the present
invention;
[0024] FIG. 12 is a schematic diagram showing a configuration of a
second heater core according to a fifth embodiment of the present
invention;
[0025] FIG. 13 is a perspective view showing a first heater core
and a second heater core according to a sixth embodiment of the
present invention;
[0026] FIG. 14 is a perspective view showing a first heater core
and a second heater core according to a seventh embodiment of the
present invention;
[0027] FIG. 15 is a schematic perspective view showing a first
heater core and a second heater core according to an eighth
embodiment of the present invention;
[0028] FIG. 16 is a schematic diagram showing an air conditioner
for a vehicle according to a ninth embodiment of the present
invention;
[0029] FIG. 17 is a schematic diagram showing an air conditioner
for a vehicle according to a tenth embodiment of the present
invention;
[0030] FIG. 18 is a schematic diagram showing an air conditioner
for a vehicle according to an eleventh embodiment of the present
invention;
[0031] FIG. 19 is a schematic diagram showing an air conditioner
for a vehicle according to a twelfth embodiment of the present
invention; and
[0032] FIG. 20 is a schematic diagram showing an air conditioner
for a vehicle, in a comparison example of the present
invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0033] Embodiments of the present invention will be described
hereafter referring to drawings. In the embodiments, a part that
corresponds to a matter described in a preceding embodiment may be
assigned with the same reference numeral, and redundant explanation
for the part may be omitted. When only a part of a configuration is
described in an embodiment, another preceding embodiment may be
applied to the other parts of the configuration. The parts may be
combined even if it is not explicitly described that the parts can
be combined. The embodiments may be partially combined even if it
is not explicitly described that the embodiments can be combined,
provided there is no harm in the combination.
First Embodiment
[0034] A first embodiment of the present invention will be
described with reference to FIGS. 1 to 8. FIG. 1 is a schematic
diagram showing an air conditioner 1 for a vehicle according to the
first embodiment of the present invention. For example, the air
conditioner of the first embodiment is mounted to a hybrid car
which obtains driving force from an engine (combustion engine) EG
and an electric motor. Thus, the engine EG is an example of a
driving device for obtaining a driving force for a vehicle running
in the invention.
[0035] In the hybrid vehicle of the embodiment, the engine EG is
operated or stopped in accordance with a traveling load of the
vehicle. Thus, the hybrid vehicle can be switched to a traveling
state in which the vehicle is traveled by using driving force from
both of the engine EG and the electrical motor for traveling, or
switched to a traveling state (i.e., EV traveling state) in which
the vehicle is traveled only by using the electrical motor for
traveling while the engine is stopped. Fuel consumption can be
reduced compared with a usual car that obtains driving force from
only engine EG.
[0036] The vehicle air conditioner 1 is provided with an interior
air conditioning unit 10 shown in FIG. 1, and an air conditioning
controller 60 (NC ECU) shown in FIG. 5.
[0037] The interior air conditioning unit 10 is located inside of
an instrument panel (i.e., dash panel) positioned at the frontmost
portion in the vehicle compartment. The interior air conditioning
unit 10 includes an air conditioning casing 11 forming an outer
shell and defining the air passage. In the air conditioning casing
11, a blower 12, an evaporator 13, a first heater core 14, a second
heater core 15 and the like are disposed.
[0038] The casing 11 defines the air passage through which air
flows into the vehicle compartment. The casing 11 is made of a
resin (e.g., polypropylene) having a suitable elasticity and being
superior in the strength. An inside/outside air switching box 20 is
located at the most upstream side to selectively introduce inside
air or/and outside air into the casing 11. Here, inside air is air
inside the vehicle compartment, outside air is air outside the
vehicle compartment.
[0039] More specifically, the inside/outside air switching box 20
is provided with an inside air introduction port 21 for introducing
inside air into the casing 11, and an outside air introduction port
22 for introducing outside air into the casing 11. An
inside/outside air switching door 23 is disposed in the
inside/outside air switching box 20 to continuously adjust open
areas of the inside air introduction port 21 and the outside air
introduction port 22. Therefore, the inside/outside air switching
door 23 can adjust a ratio between a flow amount of inside air
(i.e., air inside the vehicle compartment) introduced from the
inside air introduction port 21 and a flow amount of outside air
(i.e., air outside the vehicle compartment). The inside/outside air
switching door 23 is driven by an electrical actuator 71, and
operation of the electrical actuator 71 is controlled by a control
signal output from the air conditioning controller 60.
[0040] The blower 12 is disposed in the casing 11 at a downstream
air side of the inside/outside air switching box 20, to blow air
drawn via the inside/outside air switching box 20 toward the
interior of the vehicle compartment. The blower 12 is an electrical
blower having a centrifugal multi-blade fan (e.g., sirocco fan) 12a
and an electrical motor 12b, for example. In this case, the
centrifugal multi-blade fan 12a is driven by the electrical motor
12b, and the rotational speed (air blowing amount) of the
electrical motor 12b is controlled by a control voltage output from
the air conditioning controller 60.
[0041] An evaporator 13 is disposed in the air conditioning casing
11 at a downstream air side of the blower 12 to cross all the air
passage area in the air conditioning casing 11. The evaporator 13
is a cooling heat exchanger in which the refrigerant passing
therein is heat-exchanged with air blown by the blower 12 to cool
the blown air. The evaporator 12 is one component in a refrigerant
cycle. The refrigerant cycle includes a compressor, a condenser, a
gas-liquid separator and an expansion valve, in addition to the
evaporator 13, which are generally known.
[0042] At a downstream air side of the evaporator 13, the air
passage of the casing 31 is provided with a first air passage 16
through which air after passing through the evaporator 13 flows, a
second air passage 17 used as a cool air bypass passage through
which air after passing through the evaporator 13 flows while
bypassing the first and second heater core 14, 15, and a mixing
space 18 in which air from the first air passage 16 and air from
the second air passage 17 are mixed.
[0043] In the first air passage 16, the first and second heater
cores 14 and 15 are arranged, so that air dehumidified and cooled
by the evaporator 13 flows through the first and second heater
cores 14 and 15 in this order through the first air passage 16. The
first heater core 14 is a first heating heat exchanger configured
to perform heat exchange between engine coolant (hot water) heated
by heat of the vehicle engine EG and air after passing through the
evaporator 13. Thus, the first heat core 14 heats air after passing
through the evaporator 13 in the first air passage 16. The second
heater core 15 is a second heating heat exchanger configured to
perform heat exchange between engine coolant (hot water) and air
after passing through the first heater core 14. Thus, the second
heat core 15 heats air after passing through the first heater core
14 in the first air passage 16. For example, the engine coolant is
water, or a water solution including an addition component.
[0044] Specifically, a coolant circuit 30 is provided, so that
coolant is circulated between the first and second heater cores 14,
15 and the engine EG via the coolant circuit 30. The coolant
circuit 30 is provided with a first coolant passage 31 used for the
first and second heater cores 14, 15, and a second coolant passage
32 used for a radiator 41. The first and second coolant passages
31, 32 are connected to the engine EG in parallel with respect to a
flow of the coolant from the engine EG.
[0045] The coolant passage 31 for the first and second heater cores
14, 15 is provided with a branch point 31a, a join point 31b, and
first and second coolant passages 33, 34. The coolant flowing out
of the engine EG is branched at the branch portion 31a into the
first coolant passage 33 and the second coolant passage 34, and is
joined at the join point 31b. The first heater core 14 is located
in the first coolant passage 33 so that the coolant flowing into
the first coolant passage 33 flows through the first heater core
14. The second heater core 15 is located in the second coolant
passage 34 so that the coolant flowing into the second coolant
passage 34 flows through the second heater core 15. The coolant
having passed through the first and second heater cores 14, 15
respectively is joined at the join point 31b. Thus, the first and
second heater cores 14, 15 are arranged in parallel with respect to
the flow of the engine coolant.
[0046] A thermostat 42 is located in the coolant circuit 30 at a
coolant inlet side of the engine EG. A flow amount of the coolant
flowing into the coolant passage 31 for the first and second heater
cores 14, 15 and a flow amount of the coolant flowing into the
coolant passage 32 for the radiator 41 are adjusted by the
thermostat 42. An electrical water pump 43 is disposed in the
coolant circuit 30 so that the coolant circulates in the coolant
circuit 30. The water pump 43 is controlled by the air conditioning
controller 60 such that the water pump 43 is operated even when the
engine EG is stopped. The water pump 43 may be operated by the
power from the engine EG. In this case, the water pump 43 is also
stopped when the engine EG stops.
[0047] A first coolant temperature sensor 65 is located at a
coolant outlet side of the engine EG, to detect the temperature of
the coolant flowing out of the engine EG. A second coolant
temperature sensor 66 is located to detect the temperature of the
coolant having passed through an inlet side portion 151a of the
tube 151 in the second heater core 15.
[0048] FIG. 2 is a perspective view showing first and second heater
cores 14, 15 arranged in the first air passage 16 of the casing 11
in this order in the air flow direction.
[0049] As shown in FIG. 2, the first heater core 14 includes a
plurality of tubes 141 arranged in parallel with each other, a
first header tank 142 connected to at one end side of the plurality
of tubes in a tube longitudinal direction, a second header tank 143
arranged at the other end side of the plurality of tubes 141 in the
tube longitudinal direction, and fins 144 attached to the outer
surfaces of the tubes 141 so as to facilitate heat exchange between
the coolant and air. A pipe connection portion 145 is provided at a
coolant inlet side of the first heater core 14 to be connected to
the first header tank 142, and a pipe connection portion 146 is
provided at a coolant outlet side of the first heater core 14 to be
connected to the second header tank 143. Therefore, coolant flowing
from the pipe connection portion 145 into the first header tank 142
is distributed into the tubes 141 from the first header tank 142,
and the coolant after passing through the tubes 141 is joined in
the second header tank 143 and then flows out of the pipe
connection portion 146 that is provided at the coolant outlet side
of the first heater core 14. The plural tubes 141 and the plural
fins 142 are alternately stacked in a stack direction that is
parallel to the longitudinal direction of the header tanks 142,
143, thereby forming a heat exchanging portion in which air blown
by the blower 12 is heat-exchanged with the coolant.
[0050] As shown in FIG. 2, the height dimension of the entire
second heater core 15 is made lower than the height dimension of
the entire first heater core 14. In the example of FIG. 2, both the
first and second heater cores 14, 15 are arranged on the same
surface of the casing 11, and the height dimension of the second
heater core 15 is set about half of the height dimension of the
first heater core 14. The height dimension of the second heater
core 15 may be suitably changed with respect to the height
dimension of the first heater core 14, without being limited to the
example shown in FIG. 2.
[0051] Thus, the flow resistance of the coolant flowing through the
second heater core 15 can be made larger than the flow resistance
of the coolant flowing through the first heater core 14, and
thereby the flow amount of the coolant flowing through the second
heater core 15 can be made smaller than the flow amount of the
coolant flowing through the first heater core 14. For example, the
passage sectional area of the second coolant passage 34 of the
second heater core 15 is set smaller than the passage sectional
area of the first coolant passage 33 of the first heater core 14.
More specifically, the flow resistance of the coolant flowing
through the second coolant passage 34 of the second heater core 15
is made larger than the flow resistance of the coolant flowing
through the first coolant passage 33 of the first heater core 14,
and thereby the flow amount of the coolant flowing through the
second heater core 15 is made smaller than the flow amount of the
coolant flowing through the first heater core 14.
[0052] The second heater core 15 is a heat exchanger in which a
single flat tube 151 is arranged in meandering to have a serpentine
shape. Furthermore, fines 152 are provided in the spaces between
adjacent tubes 151.
[0053] The tube 151 is made of metal such as Cu or Al, and is
formed to define a coolant passage therein. The fins 152 are made
of metal such as Cu or Al, and are formed to facilitate heat
exchange between air and coolant. The single tube 151 is bent in
meandering to have plural tube parts that are stacked alternately
with the fins 152 in a stack direction and are made to contact the
fins 152 in the stack direction. The tube 151 is folded around the
fins 152, thereby forming a heat exchanging portion in which air
blown by the blower 12 and having passed through the first heater
core 14 is heat-exchanged with the coolant. The tube 151 is
provided with tube parts 151b, 151d that are provided without
contacting the fins 152 to define a coolant passage through which
the coolant flows to a coolant outlet of the second heater core
15.
[0054] In the present embodiment, the coolant passage of the second
heater core 15 is formed separately from the first heater core 14.
An inlet-side pipe connection portion 153 is connected to one end
side of the tube 151, and an outlet-side pipe connection portion
154 is connected to the other end side of the tube 151. The pipe
connection portions 153, 154 are connected to a piping that defines
the coolant passage between the engine and the second heater core
15. Thus, the inlet-side pipe connection portion 153 is adapted as
a coolant inlet of the second heater core 15, and the outlet-side
pipe connection portion 154 is adopted as a coolant outlet of the
second heater core 15. As shown in FIGS. 2 and 3, the inlet-side
pipe connection portion 153 and outlet-side pipe connection portion
154 are arranged adjacent to each other.
[0055] In the present embodiment, the second heater core 15 is
arranged in a lower half area of the first air passage 16, the
inlet-side pipe connection portion 153 is arranged at a bottom
portion of the second heater core 15, and the outlet-side pipe
connection portion 154 is arranged at a lower side of the
inlet-side pipe connection portion 153. The tube 151 is folded from
the lower side of the second heater core 15 to have plural folded
parts.
[0056] In the present embodiment, the fin 152 is a corrugated fin
bent in a wave shape. In the example of FIG. 2, the corrugated fins
152 are configured, such that the fin pitch fp1 of the fins 152 in
a high temperature area that is at an upstream side of the coolant
flow is relatively large, and the fin pitch fp2 of the fins 152 in
a low temperature area that is a downstream side of the coolant
flow is relatively small. Here, the fin pitch Fp1, Fp2 is a
distance between adjacent fin ridges protruding on the same
side.
[0057] FIG. 3 is a schematic diagram showing a configuration of the
second heater core 15 when being viewed from a downstream air side
of the second heater core 15.
[0058] In FIGS. 2 and 3, the inlet side portion 151a positioned at
the coolant inlet side of the tube 151 and the outlet side portion
151b positioned at the coolant outlet side of the tube 151 are
arranged adjacent to each other. In the present embodiment, the
entire outer shape of the second heater core 15 is formed
approximately in a rectangular shape, the inlet side portion 151a
extends straightly at a bottom portion in the rectangular shape,
and the outlet side portion 151b extends straightly at a lower side
of the inlet side portion 151a. The inlet side portion 151a and the
outlet side portion 151b are arranged approximately in parallel
with each other.
[0059] The coolant after flowing into the inlet side portion 151a
of the tube 151 passes through the folded tube parts of the tube
151 as in the chain line arrows of FIG. 3 to be heat-exchanged with
air, and then flows into the outlet side portion 151b. Thus, the
inlet side portion 151a of the tube 151 can be adapted as a coolant
tube part before being heat-exchanged, and the outlet side portion
151b of the tube 151 can be adapted as a coolant tube part after
being heat-exchanged. The flow direction of the coolant flowing
through the outlet side portion 151b of the tube 151 is opposite to
the flow direction of the coolant flowing through the inlet side
portion 151a of the tube 151.
[0060] Furthermore, the Peltier module 50 is arranged and inserted
between the inlet side portion 151a and the outlet side portion
151b of the tube 151.
[0061] FIG. 4 is a cross-sectional view taken along the line IV-IV
of FIG. 3. The Peltier module 50 includes a plurality of Peltier
elements 51, which are formed integrally. When electrical current
flows through the Peltier element 51, heat is moved from one side
of the Peltier elements 51 to the other side of the Peltier
elements 51, thereby pumping heat. The moving direction of the heat
in the Peltier elements 51 is determined based on the flow
direction of the electrical current.
[0062] Specifically, Peltier element 51 is provided with a P-type
layer 52, an N-type layer 53, an electrode 54 electrically
connected to one P-type layer 52 and one N-type layer 53 at one end
side, and an electrode 55 electrically connected to the one N-type
layer 53 and an another P-type layer 52 at the other end side. The
P-type layer 52 and the N-type layer 53 are made of a semiconductor
or a metal, etc., and the electrodes 54 and 55 are made of metal,
which are generally known.
[0063] In the Peltier module 50, the plural Peltier elements 51 are
connected in series, and the Peltier elements 51 arranged in a
straight line are placed between a pair of insulation layers 56,
57. The insulation layers 56 and 57 are plate shapes, and are made
of ceramics or the like. In the present embodiment, electrical
current is supplied to the electrodes 54, 55, such that the one
side insulation layer 56 at a side of the inlet side portion 151a
of the tube 151 is used as a heat radiation plate, and the other
side insulation layer 57 at a side of the outlet side portion 151b
of the tube 151 is used as a heat absorption plate. The Peltier
element 51 of the Peltier module 50 is electrically turned on or
off based on a control signal outputted from the air conditioning
controller 60.
[0064] In the present embodiment, the inlet side portion 151a of
the tube 151 is provided with an open portion 161, and the open
portion 161 is closed by the heat-radiation insulation layer 56 of
the Peltier module 50. Thus, the coolant passage of the inlet side
portion 151a of the tube 151 is defined by a metal plate member and
the heat-radiation insulation layer 56, so that heat is radiated
directly to the coolant from a heat-radiation surface 56a of the
heat-radiation insulation layer 56.
[0065] Similarly, the outlet side portion 151b of the tube 151 is
provided with an open portion 162, and the open portion 162 is
closed by the heat-absorption insulation layer 57 of the Peltier
module 50. Thus, the coolant passage of the outlet side portion
151b of the tube 151 is defined by a metal plate member and the
heat-absorption insulation layer 57, so that heat is absorbed
directly from the coolant by a heat-absorption surface 57a of the
heat-absorption insulation layer 57.
[0066] The inlet side portion 151a and the outlet side portion 151b
of the tube 151 are configured such that the height of the coolant
passage inside of the inlet side portion 151a and the outlet side
portion 151b is smaller than 1 mm. More specifically, the height of
the coolant passage inside of the inlet side portion 151a and the
outlet side portion 151b is set in a range smaller than 1 mm and
larger than 1 .mu.m (e.g., some .mu.m). Here, the height of the
coolant passage inside of the inlet side portion 151a is a height
in a direction perpendicular to the surfaces of the insulation
layers 56, 57 of the Peltier module 50.
[0067] On the other hand, as shown in FIG. 1, cool air having
passed through the evaporator 13 flows into the mixing space 18
through the second air passage 17 used as the cool air bypass
passage while bypassing the first and second heater cores 14 and
15. Thus, the temperature of air (i.e., conditioned air) mixed in
the mixing space 18 is changed by adjusting a ratio between a flow
amount of air passing through the first air passage 16 and a flow
amount of air passing through the second air passage 17.
[0068] In the present embodiment, an air mix door 19 is located on
a downstream air side of the evaporator 13 at an upstream air side
of the first air passage 16 and the second air passage 17, and is
configured to continuously change a ratio between a flow amount of
air passing through the first air passage 16 and a flow amount of
air passing through the second air passage 17.
[0069] The air mix door 19 is used as a temperature adjusting unit
that adjusts the air temperature in the mixing space 18 so as to
adjust the temperature of conditioned air to be blown into the
vehicle compartment. The air mix door 19 is driven by an electrical
actuator 72, and operation of the electrical actuator 72 for the
air mix door 19 is controlled by a control signal output from the
air conditioning controller 60.
[0070] Furthermore, at the most downstream air side, the casing 11
is provided with plural opening portions 24, 25, 26 from which
conditioned air of the mixing space 18 is blown into the vehicle
compartment that is a space to be air-conditioned. For example, the
plural opening portions 24, 25, 26 include a defroster opening
portion 24, a face opening portion 25 and a foot opening portion
26.
[0071] A defroster duct (not shown) is connected to the defroster
opening portion 24, such that conditioned air is blown toward an
inner surface of a front windshield of the vehicle from a defroster
air outlet provided at a downstream end of the defroster duct. A
face duct (not shown) is connected to the face opening portion 25,
such that conditioned air is blown toward an upper side of a
passenger in the vehicle compartment from a face air outlet
provided at a downstream end of the face duct. A foot duct (not
shown) is connected to the foot opening portion 26, such that
conditioned air is blown toward a lower side of a passenger in the
vehicle compartment from a foot air outlet provided at a downstream
end of the foot duct.
[0072] Air outlet mode doors for selectively switching an air
outlet mode are provided in the casing 11. The air outlet mode
doors include a defroster door 24a for opening and closing the
defroster opening portion 24, a face door 25a for opening and
closing the face opening portion 25, and a foot door 26a for
opening and closing the foot opening portion 26. The outlet mode
doors 24a, 25a, 26a are driven by an electrical actuator 73, and
operation of the electrical actuator 73 for the outlet mode doors
24a, 25a, 26a is controlled by a control signal output from the air
conditioning controller 60.
[0073] The electric control portion of the present embodiment will
be described with reference to FIG. 5. The air conditioning
controller 60 includes a microcomputer and a circumference circuit.
The microcomputer has CPU, ROM, RAM, etc. The air conditioning
controller 60 performs various calculations and processes based on
control programs stored in the ROM, and control operation of
various equipments connected to output side of the air conditioning
controller 60. For example, various air-conditioning control
equipments such as the blower 12, various actuators 71, 72, 73 and
Peltier element 51 are connected to the output side of the air
conditioning controller 60.
[0074] Air conditioning sensor group is connected to an input side
of the air conditioning controller 60. For example, the air
conditioning sensor group includes an inside air sensor 61
configured to detect a temperature Tr of the vehicle compartment,
an outside air temperature sensor 62 configured to detect an
outside air temperature Tam , a solar sensor 63 configured to
detect a solar radiation amount Ts of the vehicle compartment, an
evaporator temperature sensor 64 configured to detect an air
temperature TE blown from the evaporator 13, the first and second
coolant temperature sensors 65, 66 for detecting the coolant
temperature TW of the engine EG. The air temperature TE blown from
the evaporator 13 corresponds to a refrigerant evaporation
temperature in the evaporator 13.
[0075] An operation panel 70 is located near the instrument panel
at the front portion of the vehicle compartment. The operation
panel 70 is connected to the input side of the air conditioning
controller 60, such that operation signals of various
air-conditioning operation switches provided in the operation panel
70 are input to the air conditioning controller 60. The
air-conditioning operation switches provided in the operation panel
70 include, for example, an operation switch (not shown) of the air
conditioner 1, an air-conditioning switch 70a for selectively
turning on or off of the compressor thereby turning on or off of
the air conditioning operation in the air conditioner 1, an
automatic switch 70b for setting or releasing an automatic control
of the air conditioner 1, an operation mode selecting switch (not
shown) for selecting an operation mode, a suction mode selecting
switch (not shown) for selectively switching an air suction mode,
an air outlet mode selecting switch (not shown) for selectively
switching an air outlet mode, an air amount setting switch (not
shown) for setting an air blowing amount of the blower 12, a
temperature setting switch 70c for setting a temperature of the
vehicle compartment, an economic switch 70d for outputting an
economy priority mode in which the refrigerant cycle is operated
with a priority of the power saving.
[0076] The air conditioning controller 60 is electrically connected
to an engine controller 80 (ENGINE ECU) which controls operation of
the engine EG. The air conditioning controller 60 and the engine
controller 80 are configured to be capable of electrically
communicating with each other. When a signal is input into one of
the controllers, the other of the controllers can control the
equipments connected to the output side based on the signal. For
example, when the air conditioning controller 60 outputs an
operation request signal to the engine controller 80, the engine
controller 80 causes the engine EG to be operated.
[0077] Next, the operation of the present embodiment with the above
configuration will be described with reference to FIG. 6. FIG. 6 is
a flow diagram showing a control process performed by the air
conditioning controller 60 in the first embodiment. The respective
steps in FIG. 6 correspond to respective function portions provided
in the air conditioning controller 60.
[0078] First, at step S1, initialization of a flag, a timer, a
control variable, and an initial position setting of a stepping
motor in respective electrical motors, and the like are
performed.
[0079] At step S2, operation signals of the operation panel 70 and
signals regarding the circumstances of the vehicle used for the air
conditioning control, that is, detection signals from the above
group of sensors 61 to 66 are read, and then the operation proceeds
to step S3. Specifically, the operation signals include a vehicle
interior setting temperature Tset set by the vehicle interior
temperature setting switch 70c, a selection signal of the air
outlet mode, a selection signal of the air suction mode, a setting
signal of the amount of air blown by the blower 12, and the
like.
[0080] At step S3, a target outlet air temperature TAO of blown air
into the vehicle compartment is calculated. The target outlet air
temperature TAO of blown air into the vehicle compartment is
calculated based on the vehicle interior setting temperature Tset
and the vehicle environment condition such as the inside air
temperature, by using the following formula F1.
TAO=Kset.times.Tset-Kr.times.Tr-Kam.times.Tam-Ks.times.Ts+C
(F1)
where Tset is a vehicle interior setting temperature set by the
vehicle interior temperature setting switch 70c, Tr is an inside
air temperature detected by the inside air sensor 61, Tam is an
outside air temperature detected by the outside air sensor 62, and
Ts is an amount of solar radiation detected by the solar radiation
sensor 63. Furthermore, Kset, Kr, Kam and Ks are gains, and C is a
constant value for a correction.
[0081] Next, at step S4, control target values of the various
equipments connected to the output side of the air conditioning
controller 60 are determined. For example, an air blowing amount
(blower level) of the blower 12, the air suction mode, the air
outlet mode, the open degree of the air mix door 19, the engine
operation request signal and ON/OFF operation of the Peltier
elements 51 and the like are determined. The air blowing amount and
the air outlet mode and the like are determined based on the target
outlet air temperature TAO. Furthermore, the air conditioning
controller 60 determines whether the engine operation request
signal is output or not based on the engine coolant temperature TW.
For example, when the engine coolant temperature TW detected by the
first coolant temperature sensor 65 is lower than a predetermined
temperature TW1, the air conditioning controller 60 outputs the
engine operation request signal to the engine EG. Next, the ON/Off
operation determination of the Peltier elements 51 will be
described.
[0082] Then, at step S5, control signals are output from the air
conditioning controller 60 to various air-conditioning control
equipments or the engine controller 80, such that the control
target values determined at step S4 can be obtained.
[0083] Thus, the blower 12 is operated to have a predetermined air
blowing amount, the air outlet mode doors are positioned to set a
desired air outlet mode, and the engine EG is operated in
accordance with the engine operation request signal output from the
air conditioning controller 60.
[0084] Next, at step S6, it is determined whether a control time
period i elapses. When it is determined that the control time
period i elapses at step S6, the control program returns to step
S2.
[0085] Next, the control process of step S4 for determining the
ON/OFF operation of the Peltier element 51 will be described in
detail. FIG. 7 is a flowchart for determining ON/OFF operation of
the Peltier element 51, according to the present embodiment.
[0086] At step S11, an air temperature TWD blown from the second
heater core 15 is calculated. The air temperature TWD is a heated
temperature of air heated by the engine coolant at least at the
second heater core 15. The air temperature TWD can be calculated by
the coolant temperature TW2 detected by the second coolant
temperature sensor 66, the air temperature TE after passing through
the evaporator 13 and the heat exchange capacity of the heater core
15 and the like. Generally, the air temperature TWD blown out of
the second heater core 15 is approximately equal to the coolant
temperature TW2 detected by the second coolant temperature sensor
66. However, an air temperature sensor for detecting the
temperature of air blown from the second heater core 15 may be used
instead of the second coolant temperature sensor 66.
[0087] Next, at step S12, the air temperature TWD blown from the
second heater core 15 is compared with the target outlet air
temperature TAO. When the air temperature TWD is lower than the
target outlet air temperature TAO at step S12, the Peltier element
51 is turned on at step S13. When the air temperature TWD is not
lower than the target outlet air temperature TAO at step S12, the
Peltier element 51 is turned off at step S14.
[0088] For example, when a long time elapses after the engine EG
stops, the coolant temperature may become lower, and thereby the
air temperature TWD may become lower than the target outlet air
temperature TAO. In this case, in the present embodiment,
electrical power is supplied to the Peltier element 51, such that
heat is absorbed from the coolant after passing through the second
heater core 15, and heat is radiated to the coolant before being
heat-exchanged in the second heater core 15. Thus, the temperature
of the coolant before being heat-exchanged and flowing into the
second heater core 15 is increased to a temperature required for
the heating of the vehicle compartment. In this case, it is prefer
to set the air mix door 19 at the maximum heating position, by the
air conditioning controller 60.
[0089] When the engine EG is operated or an elapsed time after the
stop of the engine EG is shorter, the coolant temperature is
sufficiently high. In this case, if the air temperature TWD is
equal to or higher than the target outlet air temperature TAO, it
is unnecessary to heat the engine coolant by using the operation of
the Peltier element 51. In this case, the Peltier element 51 is not
turned on by the air conditioning controller 60. In this case, the
position (open degree) of the air mix degree 19 is controlled by
the air conditioning controller 60, thereby adjusting the
temperature of conditioned air blown into the vehicle
compartment.
[0090] The operation effects of the first embodiment will be
described.
[0091] (1) when the Peltier element 51 is not provided, the coolant
flowing out of the second heater core 15 flows simply into the
engine EG. In this case, the heat quantity without being
heat-exchanged with air in the second heater core 15 may be
radiated from the surface of the engine EG.
[0092] In contrast, according to the present embodiment, because
the heat is pumped from the coolant flowing out of the second
heater core 15 to the coolant before being heat-exchanged in the
second heater core 15 by using the Peltier element 51, the heat
quantity without being heat exchanged with air in the second heater
core 15 can be further used for the heating of the vehicle
compartment. Thus, the heat quantity of the engine coolant can be
effectively used for the heating.
[0093] (2) In the present embodiment, the Peltier module 50
including the Peltier element 51 is arranged between the inlet side
portion 151a of the tube 151 of the second heater core 15 and the
outlet side portion 151b of the tube 151 of the second heater core
15.
[0094] That is, the Peltier element 51 is inserted between the
inlet side portion 151a of the tube 151 and the outlet side portion
151b of the tube 151. Thus, the inlet side portion 151a of the tube
151 can be used as a heat radiation portion which radiates heat
from the Peltier element 51 to the coolant, and the outlet side
portion 151b of the tube 151 can be used as a heat absorption
portion which absorbs heat from the coolant to the Peltier element
51. In the present embodiment, the heat radiation portion as the
inlet side portion 151a, the Peltier element 51, and the heat
absorption portion as the outlet side portion 151b can be formed
integrally.
[0095] FIG. 20 is a comparison example of a vehicle air conditioner
1 performed by the inventors of the present application. In FIG.
20, parts similar to or corresponding to those of FIG. 1 are
indicated by the same reference numbers.
[0096] The air conditioner 1 shown in FIG. 20 is provided the first
and second heater cores 14, 15, similarly to the example of FIG. 1.
Furthermore, a heat radiation portion 34a is provided in the
coolant passage 34 at an upstream side of the second heater core
15, and a heat absorption portion 34b is provided in the coolant
passage 34 at a downstream side of the second heater core 15.
Furthermore, a Peltier module 50 is arranged between the heat
radiation portion 34a and the heat absorption portion 34b. The
Peltier module 50, the heat radiation portion 34a and the heat
absorption portion 34b are combined as a single component, and are
disposed in the engine compartment outside of the casing 11.
[0097] In the vehicle air conditioner 1 shown in FIG. 20, heat is
pumped and moved by using the Peltier element of the Peltier module
50 from the coolant flowing in the heat absorption portion 34b to
the coolant flowing in the heat radiation portion 34a. Therefore,
heat of the coolant without being heat-exchanged with air in the
second heater core 15 can be effectively used for the heating.
[0098] However, in the vehicle air conditioner 1 shown in FIG. 20,
because the Peltier element 50, the heat radiation portion 34a and
the heat absorption portion 34b are arranged outside of the casing
11, a part of the heat radiated from the Peltier element cannot be
effectively used, thereby causing heat radiation loss.
[0099] In this case, the heat loss cannot be transmitted to the
coolant in the heat radiation portion 34a.
[0100] Furthermore, in the comparison example of the vehicle air
conditioner 1 shown in FIG. 20, because the Peltier module 50, the
heat radiation portion 34a and the heat absorption portion 34b are
configured separately from the casing 11, it is necessary to mount
the Peltier module 50, the heat radiation portion 34a and the heat
absorption portion 34b to the vehicle, separately from the casing
11.
[0101] In the comparison example of the vehicle air conditioner 1
shown in FIG. 20, because the heat radiation portion 34a is
arranged outside of the casing 11, heat loss may be caused from the
heat radiation portion 34a, or heat loss is caused from the coolant
while flowing from the heat radiation portion 34a outside of the
casing 11 to the second heater core 15.
[0102] In contrast, in the first embodiment shown in FIG. 1, the
heat radiation portion 151a, the Peltier module 50 and the heat
absorption portion 151b are integrated with the second heater core
15, and thereby the heat radiation portion 151a can be arranged
inside of the first air passage 16. Thus, according to the present
embodiment, the heat radiation amount of the Peltier element 51 can
be effectively used for the heating of the air blown toward the
vehicle compartment.
[0103] Furthermore, the heat radiation portion as the inlet side
portion 151a of the tube 151, the Peltier module 50 and the heat
absorption portion as the outlet side portion 151b of the tube 151
are integrated with the second heater core 15. Therefore, the heat
radiation portion 151a, the Peltier module 50 and the heat
absorption portion 151b can be easily mounted to the vehicle
together with the casing 11. For example, it is unnecessary for the
Peltier module 50 to be mounted in an engine compartment, thereby
improving mounting performance.
[0104] (3) In the present embodiment, the inlet side portion 151a
of the tube 151 is used as a part of a heat-exchanging core portion
in which the coolant is heat-exchanged with air. That is, a part of
the tube 151 that configuring the heat-exchanging core portion is
used as the heat radiation portion.
[0105] The fin 152 is also provided on the outer surface of the
inlet side portion 151a of the tube 151, used as the heat radiation
portion. Therefore, heat of the coolant flowing through the inlet
side portion 151a as the heat radiation portion can be easily
transmitted to air, thereby reducing the temperature of the heat
absorption side of the Peltier element 51.
[0106] When the temperature difference between the heat absorption
side and the heat radiation side is too enlarged, the performance
of the Peltier element 51 is decreased.
[0107] In the present embodiment, because the heat pumped from the
Peltier element 51 can be quickly transmitted to air, it can
prevent temperature increase of the coolant flowing through the
inlet side portion 151a of the tube 151, thereby preventing a
decrease in the performance of the Peltier element 51.
[0108] Thus, it is possible to facilitate the transmission of the
heat radiated from the Peltier element 51 to air.
[0109] The lower surface of the outlet side portion 151b of the
tube 151, as the heat absorption portion, is abutted to the wall
surface of the casing 11, and the upper surface of the outlet side
portion 151b of the tube 151, as the heat absorption portion, is
abutted to the Peltier module 50. Therefore, it can effectively
restrict the outlet side portion 151b of the tube 151, as the heat
absorption portion, from being exposed to the air to be blown into
the vehicle compartment. Thus, it can prevent the air from being
cooled by the coolant flowing through the outlet side portion of
the tube 151.
[0110] In the present embodiment, the passage height of the inlet
side portion 151a and the outlet side portion 151b of the tube 151,
defining the heat radiation portion and the heat absorption
portion, is set in a range of some-pm size smaller than 1 mm.
Therefore, the coolant passage of the heat radiation portion and
the heat absorption portion can be made as in a micro channel.
Thus, it is possible to cause a turbulent flow in the coolant
passage, thereby improving heat transmission efficiency of the
coolant in the heat radiation portion and the heat absorption
portion.
[0111] More preferably, the passage height of the inlet side
portion 151a and the outlet side portion 151b of the tube 151 is
set in a range from 0.2 mm to 0.85 mm. In this case, the heat
transmission efficiency of the coolant in the inlet side portion
151 a as the heat radiation portion and in the outlet side portion
151b as the heat absorption portion can be more increased.
[0112] FIG. 8 is a graph showing the relationship between the
passage height of the tube 151 and the heat transmission
efficiency. The heat transmission efficiency of the tube 151 is
calculated by using a generally know method, in a case where the
passage width of the tube 151 is set at 10 mm. As shown in FIG. 8,
the heat transmission efficiency is gradually decreased as the
passage height becomes higher. When the passage height of the tube
151 becomes equal to or higher than 0.85 mm, the heat transmission
efficiency is rapidly decreased. When the passage height of the
tube 151 is smaller than 0.20 mm, pressure loss in the tube 151 may
be increased.
Second Embodiment
[0113] A second embodiment of the present invention will be
described with reference to FIG. 9. FIG. 9 shows a second heater
core 15 according to the second embodiment.
[0114] In the above-described first embodiment, the second heater
core 15 is configured such that the coolant passage of the tube 151
from the inlet side portion 151a to the outlet side portion 151b is
formed in meandering.
[0115] In contrast, in the second embodiment, the tube 151
including the inlet side portion 151 and the outlet side portion
151b are configured, such that the coolant flowing into the inlet
side portion 151a of the tube 151 is branched into plural passages
of plural tube parts 151m extending straightly upwardly, and is
joined to flow into the outlet side portion 151b as in the chain
line arrows of FIG. 9. The tube parts 151m are arranged in
parallel, in a direction perpendicular to the extension direction
of the inlet side portion 151a and the outlet side portion 151b. On
end sides of the plural tube parts 151m are connected to the inlet
side portion 151a to communicate with the inlet side portion 151a,
and the other end sides of the plural tube parts 151m are joined in
a join portion 151n, and the join portion 151n is connected to the
outlet side portion 151b of the tube 151 to communicate with the
outlet side portion 151b.
[0116] That is, the coolant flow passage between the inlet side
portion 151a as the heat radiation portion of the Peltier element
and the outlet side portion 151b as the heat adsorption portion of
the Peltier element can be arbitrarily changed based on heat
exchanging capacity or the flow amount of the coolant of the second
heat core 150.
[0117] In a case where the flow amount of the coolant flowing
through the second heater core 15 is smaller than that of the first
heater core 14, the tube 151 is preferably formed into a serpentine
shape similarly to the first embodiment. In this case, a
temperature distribution in air blown from the second heater core
15 can be made smaller, and thereby the temperature of air blown
from the second heater core 15 can be made in uniform. In the
second embodiment, because the coolant flows through the tube parts
151m in one way, a temperature difference may be caused. However,
in this case, the pressure loss in the tube 151 can be reduced,
thereby increasing the flow amount of the coolant flowing into the
tube 151. In the second embodiment, the other parts of the second
embodiment are similar to those of the above-described first
embodiment.
Third Embodiment
[0118] A third embodiment will be described with reference to FIG.
10. FIG. 10 shows a second heater core 15 according to the third
embodiment. In the third embodiment, the arrangement range of the
Peltier module 50 is enlarged as compared with the above-described
first embodiment.
[0119] More specifically, as shown in FIG. 10, an inlet side
portion of the tube 151 as the heat radiation portion is configured
by two straight inlet side portions 151a, 151c that are connected
perpendicularly. The inlet side portion 151a positioned upstream of
the inlet side portion 151c in the coolant flow direction is
arranged at the bottom portion in the entire rectangular shape of
the heater core 15, and the inlet side portion 151c positioned
downstream of the inlet side portion 151a in the coolant flow
direction is arranged at one side portion of the entire rectangular
shape of the heater core 15. Similarly, as shown in FIG. 10, an
outlet side portion of the tube 151 as the heat absorption portion
is configured by two straight inlet side portions 151b, 151d that
are connected perpendicularly. The outlet side portion 151b
positioned downstream of the outlet side portion 151d in the
coolant flow direction is arranged at the bottom portion in the
entire rectangular shape of the heater core 15, and the outlet side
portion 151d positioned upstream of the outlet side portion 151b in
the coolant flow direction is arranged at the one side portion of
the entire rectangular shape of the heater core 15.
[0120] Furthermore, in the second heater core 15 shown in FIG. 10,
two plate-shaped Peltier modules 50 are arranged in 1 L-shape
between the inlet side portions 151a, 151c of the tube 151 as the
heat radiation portion, and the outlet side portion 151b, 151d of
the tube 151 as the heat absorption portion. In the above-described
third embodiment, the other parts are similar to those of the
above-described first embodiment.
Fourth Embodiment
[0121] A fourth embodiment of the present invention will be
described with reference to FIG. 11. FIG. 11 shows a second heater
core 15 according to the fourth embodiment. In the fourth
embodiment, the arrangement range of the Peltier module 50 is
further enlarged as compared with the above-described third
embodiment.
[0122] More specifically, as shown in FIG. 11, an inlet side
portion of the tube 151 as the heat radiation portion is configured
by three straight inlet side portions 151a, 151c, 151e that are
connected in this order. The inlet side portion 151a positioned
most upstream of the inlet side portion 151c in the coolant flow
direction is arranged at the bottom portion in the entire
rectangular shape of the heater core 15, the inlet side portion
151c positioned downstream of the inlet side portion 151a in the
coolant flow direction is arranged at one side portion of the
entire rectangular shape of the heater core 15, and the inlet side
portion 151e positioned downstream of the inlet side portion 151c
in the coolant flow direction is arranged at the top side portion
of the entire rectangular shape of the heater core 15. Similarly,
as shown in FIG. 11, an outlet side portion of the tube 151 as the
heat absorption portion is configured by three straight outlet side
portions 151b, 151d, 151f that are connected in this order. The
outlet side portion 151b positioned most downstream in the coolant
flow direction is arranged at the bottom portion in the entire
rectangular shape of the heater core 15, the outlet side portion
151d positioned upstream of the outlet side portion 151b in the
coolant flow direction is arranged at the one side portion of the
entire rectangular shape of the heater core 15, and the outlet side
portion 151f positioned upstream of the outlet side portion 151d in
the coolant flow direction is arranged at the top side portion of
the entire rectangular shape of the heater core 15
[0123] Furthermore, in the second heater core 15 shown in FIG. 10,
three plate-shaped Peltier modules 50 are arranged in a U-shape
between the inlet side portions 151a, 151c, 151f of the tube 151 as
the heat radiation portion, and the outlet side portion 151b, 151d,
151f of the tube 151 as the heat absorption portion. In the
above-described fourth embodiment, the other parts are similar to
those of the above-described first embodiment.
Fifth Embodiment
[0124] A fifth embodiment of the present invention will be
described with reference to FIG. 12. FIG. 12 shows a second heater
core 15 according to the fifth embodiment. In the fifth embodiment,
the arrangement range of the Peltier module 50 is further enlarged
as compared with the above-described fourth embodiment.
[0125] More specifically, as shown in FIG. 12, an inlet side
portion of the tube 151 as the heat radiation portion is configured
by four straight inlet side portions 151a, 151c, 151e, 151g that
are connected in this order. The inlet side portion 151a positioned
most upstream in the coolant flow direction is arranged at the
bottom portion in the entire rectangular shape of the second heater
core 15, the inlet side portion 151c positioned downstream of the
inlet side portion 151a in the coolant flow direction is arranged
at one side portion of the entire rectangular shape of the heater
core 15, the inlet side portion 151e positioned downstream of the
inlet side portion 151c in the coolant flow direction is arranged
at the top side portion of the entire rectangular shape of the
heater core 15, and the inlet side portion 151g positioned
downstream of the inlet side portion 151e in the coolant flow
direction is arranged at the other one side portion of the entire
rectangular shape of the heater core 15. Similarly, as shown in
FIG. 12, an outlet side portion of the tube 151 as the heat
absorption portion is configured by four straight inlet side
portions 151b, 151d, 151f, 151h that are connected in this order.
The outlet side portion 151b positioned most downstream in the
coolant flow direction is arranged at the bottom portion in the
entire rectangular shape of the heater core 15, the outlet side
portion 151d positioned upstream of the outlet side portion 151b in
the coolant flow direction is arranged at the one side portion of
the entire rectangular shape of the heater core 15, the outlet side
portion 151f positioned upstream of the outlet side portion 151d in
the coolant flow direction is arranged at the top side portion of
the entire rectangular shape of the heater core 15, and the outlet
side portion 151h positioned upstream of the outlet side portion
151f in the coolant flow direction is arranged at the other one
side portion of the entire rectangular shape of the heater core
15.
[0126] Furthermore, in the second heater core 15 shown in FIG. 12,
four plate-shaped Peltier modules 50 are arranged in a part of the
rectangular shape between the inlet side portions 151a, 151c, 151e,
151g of the tube 151 as the heat radiation portion, and the outlet
side portion 151b, 151d, 151f, 151h of the tube 151 as the heat
absorption portion. In the above-described third embodiment, the
other parts are similar to those of the above-described first
embodiment.
Sixth Embodiment
[0127] A sixth embodiment of the present invention will be
described with reference to FIG. 13. FIG. 13 is a perspective view
showing first and second heater cores 14, 15 according to the sixth
embodiment of the present invention. In the sixth embodiment, as
shown in FIG. 13, the outlet side portion 151b of the tube 151 is
arranged outside of the first air passage 16, with respect to the
second heater core 15 shown in FIG. 2 described in the first
embodiment.
[0128] More specifically, an opening portion penetrating through a
wall portion of the casing 11 is provided, and the outlet side
portion 151b of the tube 151 is fixed to the casing 11 in a state
that the outlet side portion 151b is arranged in the opening
portion of the casing 11.
[0129] Instead of the opening portion, a recess portion recessed in
the inner wall surface of the casing 11 may be provided such that
the outlet side portion 151b is arranged in the recess portion. In
the present embodiment, the inlet side portion 151a of the tube 151
and the Peltier module 50 are arranged above the wall surface of
the casing 11 defining the first air passage 16, while the outlet
side portion 151b of the tube 151 is not arranged in the first air
passage 16 of the casing 11.
[0130] Because the outlet side portion 151b of the tube 151 is not
exposed in the air flowing through the first air passage 16, it can
prevent the air passing through the first air passage 16 from being
re-cooled by the coolant in which heat has been absorbed.
[0131] In the present embodiment, the heat radiation portion 151a,
the Peltier module 50 and the heat absorption portion 151b are
integrated with the second heater core 15, thereby improving the
mounting performance in the vehicle. In the above-described sixth
embodiment, the other parts are similar to those of the
above-described first embodiment.
Seventh Embodiment
[0132] A seventh embodiment of the present invention will be
described with reference to FIG. 14. FIG. 14 is a perspective view
showing first and second heater cores 14, 15 according to the
seventh embodiment of the present invention. In the seventh
embodiment, the first heater core 14 and the second heater core 15
are fixed to each other by using a connection member.
[0133] As shown in FIG. 14, a pipe connection portion 153 at the
coolant inlet side of the second heater core 15 is made to
communicate with a pipe connection portion 145 at the coolant inlet
side of the first heater core 14, and a pipe connection portion 154
at the coolant outlet side of the second heater core 15 is made to
communicate with a pipe connection portion 146 at the coolant
outlet side of the first heater core 14, with respect to the
arrangement of the first and second heater cores 14, 15 shown in
FIG. 2. Therefore, a single coolant inlet is provided in the pipe
connection portion 145 for both the first and second heater cores
14, 15, and a single coolant outlet is provided in the pipe
connection portion 146 for both the first and second heater cores
14, 15. The coolant from the single coolant inlet of the pipe
connection portion 145 is branched into first and second coolant
streams flowing to respectively the first heater core 14 and the
second heater core 15. Furthermore, the coolant flowing from both
the first heater core 14 and the second heater core 15 are joined
and flows out of the single coolant outlet of the pipe connection
portion 146.
[0134] In the prevent embodiment, the number of the pipe connection
portions can be reduced, thereby reducing the pipe connection
steps, as compared with the above described first embodiment. In
the above-described seventh embodiment, the other parts are similar
to those of the above-described first embodiment.
Eighth Embodiment
[0135] An eighth embodiment of the present invention will be
described with reference to FIG. 15. FIG. 15 is a schematic
perspective view showing first and second heater cores 14, 15
according to the eighth embodiment of the present invention. In the
eighth embodiment, a communication portion communicating with the
coolant outlet 147 of the first heater core 14 is provided with
respect to the second heater core 15 of FIG. 2 described in the
first embodiment, such that the coolant flowing out of the first
heater core 14 is joined with the coolant flowing in the outlet
side portion 151b of the tube 151 of the second heater core 15.
[0136] Thus, when the temperature of the coolant flowing out of the
first heater core 14 is higher than the temperature of the coolant
after being heat-exchanged in the second heater core 15, the
temperature of the coolant flowing through the outlet side portion
151 of the tube 151 can be increased, thereby reducing the
temperature difference between the coolant flowing through the
inlet side portion 151a of the tube 151 and the coolant flowing
through the outlet side portion 151b of the tube 151.
[0137] Generally, the heat radiation amount of the Peltier element
51 becomes relatively larger, as a temperature difference between
the heat absorbing side and the heat radiating side of the Peltier
element 53 is smaller. Thus, according to the present embodiment,
it is possible to make the heat radiation amount of the Peltier
element 51 to be larger, and thereby it is possible to increase the
temperature of the coolant flowing through the inlet side portion
151a of the tube 151.
[0138] The position of the communication portion 155 provided in
the second heater core 15 may be suitably changed only if the
coolant from the first heater core 14 is joined with the coolant of
the tube 151 before being heat-absorbed by the Peltier element 51.
For example, the communication portion 155 may be provided in any
position (e.g., a middle position, a position upstream of the
middle position) of the outlet side portion 151b of the tube 151.
In the above-described sixth embodiment, the other parts are
similar to those of the above-described first embodiment.
Ninth Embodiment
[0139] A ninth embodiment of the present invention will be
described with reference to FIG. 16. FIG. 16 is a schematic diagram
showing an air conditioner 1 for a vehicle according to the ninth
embodiment of the present invention. In the air conditioner 1
according to any one of the above-described first to eighth
embodiments, two heater cores such as the first and second heater
cores 14, 15 are disposed. In the air conditioner 1 of the present
embodiment, a single heater core 15 is disposed to heat air to be
blown into the vehicle compartment. In the present embodiment, the
heater core 14 described in the first embodiment is deleted in the
air conditioner 1. Thus, the coolant circuit for the heater core 14
is also deleted.
[0140] In the present embodiment, the present invention can be
suitably used for an air conditioner with a single heater core. In
the above-described ninth embodiment, the other parts are similar
to those of any one of the above-described first to eighth
embodiments.
Tenth Embodiment
[0141] A tenth embodiment of the present invention will be
described with reference to FIG. 17. FIG. 17 is a schematic diagram
showing an air conditioner 1 for a vehicle according to the tenth
embodiment of the present invention. In the above-described
embodiments, the single engine cooling system is provided for the
first and second heater cores 14, 15. Thus, when the first and
second heater cores 14, 15 are provided, the cooling water from the
single engine cooling system is branched to flow into the first and
second heater cores 14, 15. In the tenth embodiment, two engine
cooling systems are provided so that the coolant from the two
engine cooling systems respectively flows into the first and second
heater cores 14, 15.
[0142] For example, in a case where a cooling circuit for a
cylinder head (CH) of an engine EG and a cooling circuit for a
cylinder block (CB) of the engine EG are respectively provided in a
vehicle, coolant flowing out of the cylinder head 101 flows into
the first heater core 14, and the coolant flowing through the
cylinder block 102 flows into the second heater core 15.
[0143] In a stationary operation of the engine EG, because the flow
amount of the coolant flowing in the cylinder head 101 becomes
larger than the flow amount of the coolant in the cylinder block
102, the temperature of the coolant flowing out of the cylinder
head 101 becomes lower than the temperature of the coolant flowing
out of the cylinder block 102. In this case, the cylinder head 101
can be preferentially cooled, thereby reducing knock. The coolant
flowing out of the cylinder block 102 has a temperature higher than
the temperature of the coolant flowing out of the cylinder block
101, thereby effectively performing the heating operation while it
can prevent a friction increase in the engine EG.
[0144] Because the temperature of the coolant flowing into the
second heater core 15 is higher than the temperature of the coolant
flowing into the first heater core 14, heat exchanging efficiency
can be improved in both the heater cores 14, 15. In the
above-described tenth embodiment, the other parts are similar to
those of the above-described first embodiment.
Eleventh Embodiment
[0145] An eleventh embodiment of the present invention will be
described with reference to FIG. 18. FIG. 18 is a schematic diagram
showing an air conditioner 1 for a vehicle according to the
eleventh embodiment of the present invention. In the
above-described embodiments, the coolant of the engine EG is used
as the heating fluid flowing through the heater core(s). In the
eleventh embodiment, a coolant of an inverter 111 is also used as a
heating fluid for heating air.
[0146] The inverter 111 is mounted to a hybrid vehicle or an
electrical vehicle to convert an electrical current, supplied from
an electrical motor for a vehicle traveling, from the direct
current to alternate current. In the vehicle air conditioner 1 of
the eleventh embodiment, a coolant circuit is provided such that
the coolant is circulated between the second heater core 14 and the
inverter 111. Thus, the coolant after cooling the inverter 111
flows into the second heater core 15. On the other hand, the first
heater core 14 is provided in the engine coolant circuit so that
the coolant of the engine EG flows into the first heater core 14.
Thus, the coolants having different temperatures flows into both
the first heater core 14 and the second heater core 15. In the
above-described eleventh embodiment, the other parts are similar to
those of the above-described first embodiment.
Twelfth Embodiment
[0147] A twelfth embodiment of the present invention will be
described with reference to FIG. 19. FIG. 19 is a schematic diagram
showing an air conditioner 1 for a vehicle according to the twelfth
embodiment of the present invention. In the above-described
embodiments, the heat radiation portion, the heat absorption
portion and the Peltier element are formed integrally with the
heater core; however, the heat radiation portion, the heat
absorption portion and the Peltier element may be formed separately
from the heater core.
[0148] As shown in FIG. 19, a Peltier module 50, a heat radiation
portion 34a and a heat absorption portion 34b are arranged in the
first air passage 16 of the casing 111, and are fixed to the casing
11 separately from the second heater core 15.
[0149] The heat radiation portion 34a and the heat absorption
portion 34b are made of metal such as Cu or Al, and are formed to
form a coolant passage therein. Furthermore, the Peltier module 50
is arranged between the heat radiation portion 34a and the heat
absorption portion 34b. The heat radiation portion 34a and the heat
absorption portion 34b may be configured by a metal member and
insulation layers of the Peltier module 50, similarly to the above
first embodiment.
[0150] Thus, according to the present embodiment, because the heat
radiation portion 34a is arranged in the first air passage 16, the
heat amount discharged from the Peltier element 51 can be
effectively used for the heating of air to be blown into the
vehicle compartment.
[0151] Furthermore, because the Peltier module 50 is assembled into
the casing 11, the Peltier module 50 can be mounted to the vehicle
by mounting the casing 11 to the vehicle. In this case, it is
unnecessary for the Peltier module 50 to be mounted in an engine
compartment, thereby improving mounting performance.
[0152] Even in the twelfth embodiment, the heat absorption portion
34b may be arranged to contact the wall surface of the casing 11
inside of the casing 11 or outside of the first air passage 16 of
the casing 11.
Other Embodiment
[0153] Although the present invention has been fully described in
connection with the preferred embodiments thereof with reference to
the accompanying drawings, it is to be noted that various changes
and modifications will become apparent to those skilled in the
art.
[0154] (1) For example, in the above-described first embodiment,
the inlet side portion 151a as the heat radiation portion and the
outlet side portion 151b as the heat absorption portion are
configured by the metal members and the insulation layers 56, 57 of
the Peltier module 50, and thereby heat can be directly transmitted
between the insulation layers 56, 57 and the coolant in the
tube.
[0155] However, the inlet side portion 151a as the heat radiation
portion and the outlet side portion 151b as the heat absorption
portion may be configured by only the metal member of the tube 150.
In this case, the insulation layers 56, 57 of the Peltier module 50
are arranged to directly contact the metal member of the inlet side
portion 151a and the outlet side portion 151b, and thereby heat can
be transmitted between the insulation layers 56, 57 and the coolant
via the metal member of the inlet side portion 151a and the outlet
side portion 151b.
[0156] (2) In the present embodiment, the inlet side portion 151a
of the tube 151 is used as a part of a heat-exchanging portion in
which the coolant is heat-exchanged with air. However, the inlet
side portion 151a of the tube 151 may be configured such that the
coolant before being heat-exchanged with air flows through the
inlet side portion 151a without being heat-exchanged with air. Even
in this case, the inlet side portion of the tube 151 used as the
heat radiation portion can be formed integrally in the heater core
15.
[0157] (3) In the above-described embodiments, the number of the
Peltier element(s) in the Peltier module 50 may be suitably set,
and the number of the Peltier module(s) 50 may be suitably set.
[0158] (4) In the above-described embodiments provided with the
first and second heater cores 14, 15, the Peltier module 50 is
provided only in the second heater core 15; however, the Peltier
module 50 may be arranged in both the first and second heater cores
14, 15. In this case, the structure of the first heater core 14 can
be made similar to the structure of the second heater core 15.
[0159] (5) In the above-described first to ninth embodiments, the
air conditioner according to the invention may used for a hybrid
car having an engine EG and an electrical motor for a vehicle
traveling. Alternatively, the air conditioner according to the
invention may be suitably used for an idling-stop vehicle or other
kinds of vehicles such as a fuel cell vehicle or an electrical
vehicle that has a vehicle driving source other than the engine EG.
Furthermore, in a case where the heat efficiency of the engine is
improved and heat generation amount from the engine is small, the
heat source from the engine is insufficient to perform the heating.
In this case, the Peltier element 51 may be set to be always tuned
ON.
[0160] In the above-described first embodiment, the coolant of the
engine EG is used as the heating fluid flowing through the heater
core(s). Furthermore, in the eleventh embodiment, the coolant of
the inverter 111 is used as the heating fluid for heating air.
However. Other heating fluids may be used for the heating of air to
be blown into the vehicle compartment.
[0161] For example, a motor generator mounted to a hybrid vehicle
or an electrical vehicle, or a fuel cell of a hybrid vehicle
provided with an engine EG and the fuel cell may be used as a heat
generator. In this case, heat exhausted from the heat generator
mounted to the vehicle may be used in the vehicle. Furthermore, as
the coolant used as the heating fluid, water is generally used.
However, a cooling liquid for cooling a heat generator other than
water may be used, or a cooling gas for cooling a heat generator
may be used, as the heating fluid.
[0162] (6) The above described embodiments may be suitably combined
if there is no contradiction therebetween.
[0163] Such changes and modifications are to be understood as being
within the scope of the present invention as defined by the
appended claims.
* * * * *