U.S. patent application number 09/326601 was filed with the patent office on 2001-11-15 for temperature controller of vehicular battery.
Invention is credited to BIAN, JUNE, HIRAO, TOYOTAKA, MAJOR, GREGORY A., MATUDA, KENJI, MIZUTANI, HIROSHI.
Application Number | 20010040061 09/326601 |
Document ID | / |
Family ID | 23272914 |
Filed Date | 2001-11-15 |
United States Patent
Application |
20010040061 |
Kind Code |
A1 |
MATUDA, KENJI ; et
al. |
November 15, 2001 |
TEMPERATURE CONTROLLER OF VEHICULAR BATTERY
Abstract
The invention provides a temperature controller for a vehicular
battery which uses the waste heat of the engine to control the
temperature of a high temperature battery, to thereby enable
miniaturization of the vehicle and energy savings, and which can
accurately control the high temperature battery to an optimum
efficiency temperature. The battery temperature controller
comprises: a heat exchanger 11 for removing waste heat from a
vehicle engine 3; a heating loop K being a coolant circulation path
for conveying heat from the heat exchanger 11 to a vehicle high
temperature battery 5; a radiator 9 for cooling the high
temperature battery 5; a cooling loop R being a coolant circulation
path for carrying heat from the high temperature battery 5 to the
radiator 9, and connected in parallel with the heating loop K so as
to have a common path C, and a first flow control valve 60 and a
second flow control valve 61 respectively provided in the heating
loop K and the cooling loop R.
Inventors: |
MATUDA, KENJI; (NAGOYA,
JP) ; HIRAO, TOYOTAKA; (NAGOYA, JP) ;
MIZUTANI, HIROSHI; (NAGOYA, JP) ; MAJOR, GREGORY
A.; (BEVERLY HILLS, MI) ; BIAN, JUNE; (NOVI,
MI) |
Correspondence
Address: |
OBLON SPIVAK MCCLELLAND MAIER & NEUSTADT PC
FOURTH FLOOR
1755 JEFFERSON DAVIS HIGHWAY
ARLINGTON
VA
22202
US
|
Family ID: |
23272914 |
Appl. No.: |
09/326601 |
Filed: |
June 7, 1999 |
Current U.S.
Class: |
180/68.2 ;
165/41; 180/65.225; 180/65.27; 180/65.29; 903/903; 903/904;
903/907; 903/916; 903/951 |
Current CPC
Class: |
H01M 10/615 20150401;
B60L 3/003 20130101; B60H 2001/003 20130101; B60L 58/34 20190201;
B60L 2240/34 20130101; Y10S 903/904 20130101; B60L 58/33 20190201;
H01M 10/613 20150401; F01P 2060/08 20130101; B60W 10/30 20130101;
Y02T 10/7072 20130101; B60K 6/22 20130101; B60L 58/26 20190201;
B60L 58/27 20190201; Y10S 903/951 20130101; B60H 1/00278 20130101;
F01P 2031/30 20130101; H01M 10/663 20150401; B60L 1/003 20130101;
B60W 10/26 20130101; B60L 58/10 20190201; F02M 26/28 20160201; B60K
6/44 20130101; B60L 50/16 20190201; Y10S 903/916 20130101; B60K
6/40 20130101; B60L 2210/40 20130101; F01P 2060/14 20130101; F01P
7/165 20130101; Y10S 903/903 20130101; B60H 1/004 20130101; B60W
2510/246 20130101; B60L 3/0046 20130101; Y02T 10/88 20130101; B60L
50/61 20190201; F02B 29/0443 20130101; B60L 2240/36 20130101; B60L
1/02 20130101; H01M 10/6568 20150401; Y02E 60/10 20130101; B60K
6/52 20130101; B60W 2510/244 20130101; F01P 2005/105 20130101; Y02T
10/70 20130101; B60L 2210/10 20130101; Y10S 903/907 20130101; B60L
3/0061 20130101; F01P 2050/24 20130101; Y02T 10/62 20130101; Y02T
90/40 20130101; Y02T 10/72 20130101; Y02T 10/12 20130101; F01P 3/20
20130101; H01M 10/625 20150401 |
Class at
Publication: |
180/68.2 ;
165/41; 180/65.2 |
International
Class: |
B60K 011/00; B60K
006/00 |
Claims
1. A temperature controller for a vehicular battery comprising; a
heat exchanger for removing waste heat from a vehicle engine, and a
heating loop, being a coolant circulation path, for carrying heat
from said heat exchanger to a high temperature battery of a
vehicle.
2. A temperature controller for a vehicular battery according to
claim 1, wherein there is provided; a radiator for cooling said
high temperature battery, a cooling loop being a coolant
circulation path, for carrying heat from said high temperature
battery to said radiator, and connected in parallel with said
heating loop so as to have a common path with said heating loop,
and flow control means for said heating loop and said cooling
loop.
3. A temperature controller for a vehicular battery according to
claim 2, wherein said flow control means are flow control valves
respectively provided in said heating loop and said cooling
loop.
4. A temperature controller for a vehicular battery according to
claim 2, wherein said flow control means is a three way valve
provided at a junction portion of said heating loop and said
cooling loop.
5. A temperature controller for a vehicular battery according to
any one of claim 1 through claim 4, wherein said heat exchanger is
a plate type liquid heat exchanger.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a battery temperature
controller for controlling the temperature of a vehicular
battery.
[0003] 2. Description of the Related Art
[0004] Recently, there has been an increasing demand for
introducing a low-pollution vehicle and alternative energy vehicle,
accompanied with demands for improving the air environment and
environmental problems. As a strong candidate for the alternative
energy vehicle, there is the hybrid vehicle which uses an electric
motor together with an engine. A hybrid vehicle is driven by an
engine at the time of high speed driving, and is driven by a drive
motor with a battery as a power source at the time of low speed
driving. The battery is charged by driving an electric power
generation motor at the time of engine driving.
[0005] As the battery for the hybrid vehicle, there is for example
the lead acid battery, the alkaline storage battery, the metal air
storage battery, and the high temperature battery. Of these, the
high temperature battery operates stably within a high temperature
range (for example 80.about.90.degree. C.), operating with high
efficiency to thereby improve vehicle fuel consumption. That is to
say, the high temperature battery of a hybrid vehicle has an
optimum efficiency temperature (the influence of temperature on the
efficiency is greater than for the conventional lead acid battery)
greater than atmospheric temperature, and hence it is desirable to
maintain the temperature at around 80.degree. C. in consideration
of electric generating and storage efficiency and vehicle fuel
consumption. As an example of a high temperature battery, there is
one which uses a halide of for example copper, nickel, or silver,
for the positive electrode, and metallic lithium (alternatively an
activated metal such as calcium, magnesium is also possible) for
the negative electrode, and employs an organic substance such as
propylene carbonate for the electrolyte.
[0006] Since it is necessary to mount a heat source for maintaining
the temperature of the high temperature battery, on the vehicle,
then there is the problem of an increase in vehicle cost and
battery cost, and an increase in vehicle size due to the space for
mounting the heat source for the battery.
[0007] Moreover, since a cooling device is not provided solely for
the heat source, then the temperature of the high temperature
battery cannot be accurately controlled to an optimum efficiency
temperature. Hence there is room for improvement in the efficiency
for electricity generation and for electricity storage and in fuel
consumption of the vehicle.
SUMMARY OF THE INVENTION
[0008] The present invention addresses the above problems with the
conventional technology with the object of providing a temperature
controller for a vehicular battery which uses the waste heat of the
engine to heat the high temperature battery, to thereby enable
miniaturization of the vehicle and energy savings.
[0009] Moreover, another object of the invention is to provide a
temperature controller for a vehicular battery which can accurately
control the temperature of the high temperature battery to an
optimum efficiency temperature.
[0010] The temperature controller for a vehicular battery of the
present invention, to achieve the above object, comprises a heat
exchanger for removing waste heat from a vehicle engine, and a
heating loop, being a coolant circulation path, for carrying heat
from the heat exchanger to a high temperature battery of a
vehicle.
[0011] With this invention, the waste heat of the engine is used to
maintain the temperature of the high temperature battery, and hence
it is not necessary to mount a new heat source in the vehicle.
Consequently, miniaturization of the vehicle and energy saving can
be achieved.
[0012] Furthermore, according to a second aspect of the invention,
there is provided; a radiator for cooling the high temperature
battery, a cooling loop being a coolant circulation path, for
carrying heat from the high temperature battery to the radiator,
and connected in parallel with the heating loop so as to have a
common path with the heating loop, and a flow control device for
the heating loop and the cooling loop.
[0013] With this invention, at first at the time of vehicle
heating, the heating loop and the cooling loop are respectively in
the open condition and the closed condition so that high
temperature coolant which has been heated by the engine waste heat
in the heat exchanger is circulated in the heating loop to heat the
high temperature battery so as to quickly attain the warm-up
condition in the high temperature region. After this, in the case
where the temperature of the high temperature battery goes above
the optimum efficiency temperature, the cooling loop is adjusted so
as to open gradually so that low temperature coolant which has
given up heat in the radiator is circulated in the cooling loop and
mixed with coolant in the heating loop to give a high temperature
coolant mixture. Coolant at a fixed temperature is then supplied to
the high temperature battery. In this way, the high temperature
battery can be operated at an optimum efficiency point.
[0014] Here, with a third aspect, for the flow control device, flow
control valves may be respectively provided in the heating loop and
the cooling loop.
[0015] Moreover, instead of respectively providing flow control
valves in the heating loop and the cooling loop, a three way valve
may be provided at the junction portion of the heating loop and the
cooling loop so that the abovementioned temperature control can be
effected by operating a single three way valve.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a diagram showing an arrangement of a hybrid
vehicle according to the present invention.
[0017] FIG. 2 is a perspective view of an HPVM mounted in the
hybrid vehicle.
[0018] FIG. 3 is a block diagram of the hybrid vehicle.
[0019] FIG. 4 is a diagram showing a refrigerant path of an air
conditioner mounted in the hybrid vehicle.
[0020] FIG. 5 is a diagram showing the flow of coolant in the
hybrid vehicle.
[0021] FIG. 6 is a schematic diagram of an embodiment of a
temperature controller for a vehicular battery, of the present
invention.
[0022] FIG. 7 is a graph showing a relationship between temperature
of a high temperature battery and efficiency.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] Next is a description of an embodiment of a temperature
controller for a vehicular battery, with a hybrid vehicle given as
an example.
[0024] At first, as shown in FIG. 1, numeral 1 denotes a hybrid
vehicle, equipped with a drive unit 2 (apparatus to be cooled) in
the front part of the vehicle having a motor 2a housed therein for
driving front wheels, and an engine 3 (a turbocharged engine in
this example, but not limited to this) in the rear part of the
vehicle for driving rear wheels. The hybrid vehicle 1 runs at the
time of low speed driving, using the driving motor 2a as a drive
source, while above a fixed speed the drive source is changed to
the engine 3 for running. Since the motor 2a is provided in the
front part of the vehicle, the engine 3 is arranged in the rear
part of the vehicle, for the reason of mounting space and in
consideration of air resistance. There is also the case where the
engine 3 and the motor 2a are activated as the drive source at the
same time.
[0025] Numeral 5 denotes a battery (apparatus to be cooled) which
is a power source for the motor 2a, and numeral 6 denotes a
motor-generator unit (apparatus to be cooled) for converting the
driving force of the engine 3 into electrical power and storing the
electrical power in the battery 5. An electrical power generation
motor (not shown) is mounted in the motor-generator unit 6, and
electrical power is generated by transmitting the driving force of
the engine 3 to the electrical power generation motor. Moreover,
the motor-generator unit 6 has the function of converting
electrical power stored in the battery 5 into the driving force, by
driving the electrical power generation motor with the electrical
power. Here the battery 5 of this example is a high temperature
battery of the liquid heated type which is stable in a high
temperature range (for example 80.degree. C..about.90.degree. C.)
with a high operating efficiency. As an example of a high
temperature battery, there is one which uses a halide of for
example copper, nickel, or silver, for the positive electrode, and
metallic lithium (alternatively an activated metal such as calcium,
magnesium is also possible) for the negative electrode, and employs
an organic substance such as propylene carbonate for the
electrolyte.
[0026] Numeral 50 denotes an I/C (intercooler) EGR system
(apparatus to be cooled). This system 50 is provided with an EGR
(Exhaust Gas Recirculation) unit 50a, and an intercooler 50b. That
is to say, the engine 3 is provided with an EGR (Exhaust Gas
Recirculation) unit 50a for reintroducing a part of the exhaust gas
back into the engine 3 to thereby reduce the NOx in the exhaust
gas. In addition an intercooler 50b is provided between a turbo
charger (not shown in the figure) and an intake manifold (not shown
in the figure) for reducing the intake temperature. The EGR 50a and
the intercooler 50b are both liquid cooled types.
[0027] As shown in FIG. 1, numeral 8 denotes a first radiator for
cooling the engine 3, and 9 denotes a second radiator provided
together with the first radiator 8. The second radiator 9 is for
cooling the high temperature battery 5, the driving motor 2a, the
motor-generator unit 6 and the I/C EGR system 50. The first
radiator 8 and second radiator 9 are so constructed that heat is
discharged to the surrounding air by a fan 10 for the cooling
radiators. Moreover, there is provided a battery heat exchanger 11
(coolant heating device) for transferring heat from the engine 3 to
the high temperature battery 5.
[0028] Next is a description of a vehicle air conditioning
apparatus (referred to hereunder as an air conditioner) mounted in
the hybrid vehicle 1.
[0029] In FIG. 1, numeral 12 denotes a compressor unit for
compressing a refrigerant, 13 denotes a heat exchanger, 14 denotes
a fan for blowing air to the heat exchanger 13, and 15 denotes a
module referred to as an HPVM (Heat Pump Ventilating Module). The
heat exchanger 13 is provided on the right side of the vehicle body
for facilitating heat exchange with outside air, and heat is
forcibly exchanged with outside air by the fan 14. The HPVM 15 is
arranged in the middle of the rear part of the vehicle body, and is
connected to a duct 16 extending to the front of the vehicle body
along a center of the lower part of the vehicle body. As shown in
FIG. 3, the duct 16 is formed in a tubular shape, and is provided
with air outlet sections 17 and 18 in the central portion and in
the front end of the duct 16, respectively.
[0030] The HPVM 15 will now be described in detail.
[0031] FIG. 2 shows a perspective view of the HPVM 15, and FIG. 3
shows a block diagram of the air conditioner.
[0032] In FIG. 2, the HPVM 15 is constructed with a casing, 15a, an
inside air intake 21, an outside air intake 22, a discharge port 23
and a connecting portion 24 for connecting the HPVM to the duct 16.
The inside air intake 21 is communicated with the vehicle cabin,
and the outside air intake 22 and the discharge port 23 are
communicated with outside of the vehicle cabin.
[0033] Moreover, as shown in FIG. 3, the HPVM 15 is equipped with
an inside air/outside air changeover damper 30 for determining
which of either air inside of the vehicle cabin (inside air) or air
outside of the vehicle cabin (outside air) is to be drawn in, a fan
31 for introducing air via the inside air/outside air changeover
damper 30, a heat exchanger 33 for exchanging heat between the
introduced air and the refrigerant, an air mix damper 34 for
branching a part of the heat exchanged air, and a heater core 35
for heating the branched air.
[0034] By opening or closing the inside air/outside air changeover
damper 30, it is possible to select either one of an inside air
circulating operation for drawing in inside air from the inside air
intake 21 (see FIG. 2) and sending the air to the duct 16, or an
outside air introducing operation for introducing outside air from
the outside air intake 22 (see FIG. 2) and sending the air to the
duct 16, as well as discharging inside air from the discharge port
23 (see FIG. 2).
[0035] The heater core 35 is a heat exchanger for receiving a
supply of high temperature coolant from the engine 3, as described
below, and heating a flow of introduced air. This is used
supplementarily at the time of the heating operation (heat pump
operation) of the air conditioner. The air mix damper 34 is for
adjusting the quantity of introduced air branched off to the heater
core 35, according to the opening thereof. The introduced air is
then blown to the vehicle cabin from the air outlet sections 17 and
18 of the duct 16.
[0036] The cooling operation or heating operation is effected by
supplying refrigerant to the heat exchanger 33 and the heat
exchanger 13 by the compressor unit 12. FIG. 4 shows the compressor
unit 12.
[0037] As shown in FIG. 4, the compressor unit 12 includes, as main
components, a compressor 41, a throttling resistance 42, a four way
valve 43 and an accumulator 44. The above described heat exchangers
13 and 33 are connected between these respective devices by a
refrigerant path 45 to form a refrigerant circuit.
[0038] A driving force is transmitted to the compressor 41 by the
engine 3 or the motor-generator unit 6. The compressor 41 has the
function of compressing the refrigerant which has absorbed heat and
been gasified in an evaporator, and discharging and sending the
refrigerant as a high temperature and high pressure gas refrigerant
to the four way valve 43. By switching the four way valve 43, the
flow direction of the high temperature and high pressure gas
refrigerant discharged from the compressor 41 is changed, resulting
in changeover of the cooling or heating operation. Moreover, the
throttling resistance 42 has the function of decompressing and
expanding the high temperature and high pressure liquid refrigerant
to give a low temperature and low pressure liquid refrigerant. This
uses a capillary tube or an expansion valve. The accumulator 44 is
provided for removing the liquid component contained in the gas
refrigerant, so as to prevent a part of the liquid refrigerant
which has not been evaporated completely by the evaporator from
being drawn in directly to the compressor 41.
[0039] With the above described refrigerant circuit, at the time of
the heating operation, the low temperature and low pressure liquid
refrigerant is evaporated and gasified in the heat exchanger 33
(which operates as a condenser at the time of cooling) by absorbing
heat from outside air, to become a low temperature and low pressure
gas refrigerant, and is then sent to the compressor 41 and is
compressed into a high temperature and high pressure gas
refrigerant. Thereafter, in the heat exchanger 13 (which operates
as an evaporator at the time of cooling) the gas refrigerant
releases heat to heat the air and is condensed and liquefied, after
which it is expanded by passing through the throttling resistance
42 to become a low temperature and low pressure liquid refrigerant,
and is circulated again to the heat exchanger 33. In this case, the
heat exchanger 33 operates as an evaporator and cools the heating
medium. Moreover, the heat exchanger 13 functions as a condenser
and heats the refrigerant.
[0040] At the time of the cooling operation, the high temperature
and high pressure gas refrigerant supplied to the heat exchanger 33
is condensed and liquefied by discharging heat to the outside air.
This is then expanded by the throttling resistance 42, and sent to
the heat exchanger 13 to be evaporated and gasified, and is then
sent to the compressor 41 and is again circulated to the heat
exchanger 33. In this case, the heat exchanger 33 functions as a
condenser and the heat exchanger 13 functions as an evaporator.
That is to say, one of the heat exchangers of the cooling apparatus
arranged in the air conditioner, by switching the four way valve,
operates as an evaporator to demonstrate a cooling ability, and may
also operate as a condenser to function as a heater. When operated
as an evaporator, cooling, dehumidifying and temperature adjustment
is possible, while when operated as a heater, this can act in place
of the heater core. Therefore, even when the engine cooling water
temperature is low so that there is no heating effect, heating
ability can be demonstrated. Moreover, this supplementary heating
operation immediately after starting the engine operation naturally
has a sufficient heating ability for when driving under electrical
power, without using the engine.
[0041] With the above construction, for safe operation it is
required that the temperature of the above described drive unit 2
and the motor-generator unit 6 is not higher than 65.degree. C.
Moreover, the temperature of the high temperature battery 5 is
ideally 85.+-.5.degree. C. from the view point of storage
efficiency. To satisfy this requirement, in the hybrid vehicle 1,
the temperature of the coolant is controlled as described
below.
[0042] As shown in FIG. 5, there are formed predetermined flow
paths for flowing a coolant between the engine 3, the high
temperature battery 5, the I/C EGR system 50, the drive unit 2, the
motor-generator unit 6, the first radiator 8, the second radiator 9
and the battery heat exchanger 11.
[0043] The engine 3 is cooled by the first radiator 8, and the high
temperature battery 5, the I/C EGR system 50, the drive unit 2 and
the motor-generator unit 6 are cooled by the second radiator 9.
[0044] Next is a detailed description of the flow path.
[0045] The I/C EGR system 50, the drive unit 2 and the
motor-generator unit 6 are cooled by a coolant supplied from the
second radiator 9.
[0046] First, the coolant is supplied from the outlet side of the
second radiator 9 to the flow path 51. The coolant is branched, at
a branch point p1, to the I/C EGR system 50 side and the drive unit
2 and motor-generator unit 6 side.
[0047] The coolant branched to the I/C EGR system 50 side is
supplied into the I/C EGR system 50 via an inter-cooler coolant
pump 53 (circulation quantity control device) interposed in a flow
path b1. After cooling the apparatus system in the I/C EGR system
50, the coolant is again circulated to the second radiator 9 via a
flow path 52. At this time, a flow velocity is given to the coolant
by the inter-cooler coolant pump 53 to make the coolant flow in the
flow path b1.
[0048] On the other hand, the coolant branched to the drive unit 2
and the motor-generator unit 6 side is further branched at a branch
point p2, after which a part of the coolant is further branched via
a traction coolant pump 54 (circulation quantity control device).
One part is branched to a flow path b2 on the drive unit 2 side,
and the other is branched to a flow path b3 on the motor-generator
unit 6 side. The coolant after branching is supplied to the drive
unit 2 and the motor-generator unit 6, respectively, similar to the
coolant supplied to the I/C EGR system 50, for cooling the
apparatus system, and is then again circulated to the second
generator 9 via the flow path 52. At this time, a flow velocity is
given to the coolant by the traction coolant pump 54 to make the
coolant flow in the flow paths b2 and b3.
[0049] Here, the drive unit 2 is disposed in the front part of the
vehicle body, as shown in FIG. 1. On the other hand, the
motor-generator unit 6 and the second radiator 9 are disposed in
the rear part of the vehicle body. That is, the flow path b2 is
longer than the flow path b3, and has a larger coolant flow
resistance. Therefore, when it is necessary to make the coolant
flow to both the drive unit 2 and the motor-generator unit 6, the
flow rate on the motor-generator unit 6 side becomes higher than
that on the drive unit 2 side, resulting in uneven balance. To
solve this problem, a flow regulating valve 55 is interposed in the
flow path b3 to maintain the flow rate balance with the flow path
b2.
[0050] The other coolant branched at the branch point p2 flows to
the high temperature battery 5 side in a flow path b4 in which a
battery coolant pump 57 (circulation quantity control device) is
interposed.
[0051] At a junction p4 before the battery coolant pump 57, this
merges with a high temperature coolant heated by the heat of the
engine 3. The high temperature coolant will be described later. The
flow rate is adjusted beforehand so that after merging, the coolant
attains a predetermined temperature (85.+-.5.degree. C.).
[0052] Thereafter, the coolant is supplied to the high temperature
battery 5, and discharged to the outlet flow path b5, while
maintaining the high temperature battery 5 within the above
described predetermined temperature. The coolant is branched at a
branch point p3 to flow paths b6 and b7. The construction is such
that the flow path b6 passes through the battery heat exchanger 11
and joins the flow path b4 at the junction p4, and the flow path b7
joins the flow path 52 and is then circulated again to the second
radiator 9. A first flow regulating valve 60 is interposed in the
flow path b6, and a second flow regulating valve 61 is interposed
in the flow path b7. The flow regulating valves 60 and 61 will be
described later.
[0053] The coolant flowing in the flow path b6 is heated by the
heat of the engine 3 in the battery heat exchanger 11. In more
detail, in the battery heat exchanger 11, heat is exchanged between
the flow path b6 and the flow path b10 which circulates the coolant
between the engine 3 and the battery heat exchanger 11. Since the
temperature of the coolant in the flow path b10 heated by the
engine 3 is higher than that of the coolant in the flow path b6
(85.+-.5.degree. C.), the coolant in the flow path b6 is heated to
become a high temperature coolant, and merges with the low
temperature coolant in the flow path b4 at the junction p4.
[0054] In this way, the high temperature coolant and the low
temperature coolant merge at the junction p4, to thereby supply the
above described coolant having a predetermined temperature to the
high temperature battery 5. By adjusting the quantity of the high
temperature coolant by the above described flow regulating valves
60 and 61, the temperature of the coolant supplied to the high
temperature battery 5 is controlled to the optimum efficiency
temperature K (85.degree. C.) as shown in FIG. 7.
[0055] A description of the characteristic parts of the embodiment
will now be given.
[0056] As shown in FIG. 5 and FIG. 6, the high temperature battery
5, the heat exchanger 11 and the circulation pump 57 are provided
in a heating loop K (coolant circulation path) comprising the flow
paths b5 and b6. The first flow control valve 60 is provided in the
heating loop K. Opposite ends of a cooling loop R (coolant
circulation path) comprising flow paths 51, 52, b4 and b7 are
connected in parallel with the heating loop K so as to have a
common path C. The second flow control valve 61 is provided in the
cooling loop R. The flow control device comprises the first flow
control valve 60 and the second flow control valve 61.
[0057] At the time of vehicle heating, the first flow control valve
60 and the second flow control valve 61 are respectively in the
open condition and the closed condition, so that high temperature
coolant which has been heated by the waste head from the engine 3
in the heat exchanger 11 is circulated in the heating loop K to
heat the high temperature battery 5 so as to quickly attain the
warm-up condition in the high temperature region. After this, in
the case where the temperature of the high temperature battery 5
goes above the optimum efficiency temperature K (85.degree. C. in
this embodiment as shown in FIG. 7), the second flow control valve
61 is adjusted so as to open gradually so that the low temperature
coolant which has given up heat in the second radiator 9 is
circulated in the cooling loop R and mixed with coolant in the
heating loop K to give a high temperature coolant mixture. Coolant
at a fixed temperature is then supplied to the high temperature
battery. In this way, the high temperature battery can be operated
at an optimum efficiency point.
[0058] The heat exchanger 11 is a plate type liquid heat exchanger
which employs a liquid with a high specific heat capacity. This can
be smaller than the conventional commonly used heating and cooling
units using air.
[0059] Instead of respectively providing the flow control valves 60
and 61 in the heating loop K and cooling loop R, a three way valve
(see broken lines 60a in FIG. 6) may be provided at the junction
portion p3 of the heating loop K and the cooling loop R so that the
abovementioned temperature control can be effected by operating a
single three way valve 60a. Hence valve operation is
simplified.
[0060] Another flow path b11 to the engine 3 is provided
independent of the above described flow path b10, to circulate the
coolant between the first radiator 8 and the engine 3. Moreover, a
flow path b12 is provided to circulate the coolant between the
heater core 35 and the engine 3.
[0061] The coolant discharged from the engine 3 is branched at a
branch point p5 to flow paths b10, b11 and b12, and passes through
the battery heat exchanger 11, the first radiator 8 and the heater
core 35, respectively, after which it merges at the junction p6,
and is then circulated again to the engine 3.
[0062] An engine coolant pump 69 is provided in the flow path on
the inlet side of the engine 3, to make the coolant flow in flow
paths b10.about.b12. Moreover, in the flow paths b10 and b12 there
are provided flow regulating valves 71 and 73, respectively, and in
the flow path b11 there is provided a thermostat 72.
[0063] The first radiator 8 and the above described second radiator
9 are provided in parallel, and since the coolant flowing through
the first radiator 8 has a higher temperature, a pull (suction)
type radiator cooling fan 10 is arranged on the downstream side of
the first radiator 8, so that air passing through the second
radiator 9 passes through the first radiator 8.
[0064] Next is a description of the operation of the above
described air conditioner.
[0065] As described above, the hybrid vehicle 1 travels at the time
of low speed driving, using the driving motor 2a as a drive source
and travels at the time of high speed driving exceeding a certain
speed, by switching the drive source to the engine 3. Hence, the
drive source of the air conditioner is also different from that of
the conventional vehicular air conditioner.
[0066] First, when the hybrid vehicle 1 travels using the engine 3,
the compressor unit 12 is driven by the driving force from the
engine 3 at the time of air conditioning, to circulate the
refrigerant between the heat exchangers 13 and 33. The engine 3
also transmits a driving force to the motor-generator unit 6, and
the motor-generator unit 6 generates electrical power by a motor
(not shown), and stores the electrical power in the high
temperature battery 5.
[0067] With the HPVM 15, the fan 31 introduces inside air or
outside air via the inside air/outside air changeover damper 30 to
blow air to the heat exchanger 33. The heat of the introduced air
is exchanged with the refrigerant in the heat exchanger 33, to
thereby be heated (at the time of the heating operation), or cooled
(at the time of the cooling operation).
[0068] The air, after being heated is directed to the duct 16 or
the heater core 35 by means of the air mix damper 34, and the
introduced air sent to the heater core 35 is further heated by the
waste heat of the engine 3 and then sent to the duct 16.
[0069] On the other hand, when the motor 2a is driving and the
engine 3 is stopped, operation is as follows. That is, the
motor-generator unit 6 drives the electrical power generating motor
housed therein, using the electrical power stored in the high
temperature battery 5. The driving force is transmitted to the
compressor unit 12 to thereby circulate the refrigerant between the
heat exchangers 13 and 33. Other operation is similar to that when
the engine 3 is driving.
[0070] Next is a description of the coolant circulation. As shown
in FIG. 6, the coolant discharged from the second radiator 9 is
distributed via the flow path 51 to the various apparatus,
branching at branch points p1 and p2. That is to say, the quantity
of coolant circulated to the battery 5 is determined by the battery
coolant pump 57, and the quantity of coolant circulated to the I/C
EGR system 50 is determined by the intercooler coolant pump 53, and
the quantity of coolant circulated to the drive unit 2 and the
motor-generator unit 6 is determined by the traction coolant pump
54.
[0071] Next is a separate description of the coolant circulation
for when the engine 3 is driving, and for when the motor 2a is
driving.
[0072] When travelling using the engine 3, then as with the
conventional engine vehicle, the coolant is circulated using the
engine coolant pump 69, between the engine 3 and the first radiator
8, to thereby cool the engine 3. Moreover, the coolant is also
circulated in the I/C EGR system 50 using the intercooler coolant
pump 53.
[0073] With the motor-generator unit 6, when the electric power
generating motor housed therein is driven, the coolant is
circulated. That is to say, in the case of storing electricity
using the drive power of the engine 3, and in the case of operating
the air conditioner when the engine 3 is stopped, the coolant is
circulated to the motor-generator unit 6 using the traction coolant
pump 54, to thereby provide cooling.
[0074] On the other hand, when travelling by means of the motor 2a,
the coolant is circulated to the drive unit 2 using the traction
coolant pump 54 to thereby cool the drive unit 2.
[0075] Here, it is not necessary to cool the I/C EGR system 50 when
the engine 3 is stopped. Consequently, it is not necessary to
operate the inter-cooler coolant pump 53. Hence there is the case
where when this pump is fully stopped, the coolant is made to flow
back by the drive of another pump. For example, in the case where
the inter-cooler coolant pump 53 is stopped and the traction
coolant pump 54 is operating, the inter-cooler coolant pump 53
allows a reverse flow so that the coolant discharged from the drive
unit 2 or the motor-generator unit 6 does not flow to the second
radiator 9 but flows to the I/C EGR system 50. There is thus the
case where a route is traced circulating again to the traction
coolant pump 54 via the branch point p1.
[0076] In order to prevent this, the inter-cooler coolant pump 53
is operated even though cooling is not required for the I/C EGR
system 50, to the extent that the abovementioned reverse flow does
not occur.
[0077] That is to say, even though the engine is stopped, the
electric pump does not stop but continues to run for a fixed
period. As a result, immediately after stopping, the intercooler
and the EGR which are conventionally at a high temperature are
rapidly cooled due to this operation so that the high temperature
does not occur, thereby improving the life.
[0078] Similarly, the traction coolant pump 54 is operated even in
the case where cooling is not required for the drive unit 2 and the
motor-generator unit 6, to the extent that reverse flow of coolant
does not occur.
[0079] Moreover, the high temperature battery 5 is always
maintained at a predetermined temperature irrespective of whether
the engine 3 is driving or the motor 2a is driving. The battery
coolant pump 57 is operated corresponding to a temperature change
of the high temperature battery 5 so that high temperature coolant
which has been adjusted in flow quantity by the flow control valves
60 and 61, and low temperature coolant are mixed at the junction
point p4 to thereby maintain the temperature of the coolant
circulated to the battery 5 continuously at a predetermined
temperature.
[0080] Here with the abovementioned embodiment, the example is
given for a hybrid vehicle. However the vehicle is not limited to
this and may be a standard vehicle.
[0081] With the present invention, since this is constructed as
described above, then by using the high temperature coolant which
has been heated by the engine waste heat as the heat source for
warming up to the temperature range (80.about.90.degree. C.) for
the high temperature battery of the vehicle, temperature control of
the high temperature battery can be performed without providing a
special heater or a power source.
[0082] Moreover, by controlling the temperature of the coolant
using the heating loop and the cooling loop, then the high
temperature battery can be accurately controlled to the optimum
temperature. Consequently miniaturization of the vehicle and energy
savings can be achieved.
[0083] Furthermore, by using a plate type liquid heat exchanger
which employs a liquid with a high specific heat capacity, then
this can be smaller than the conventional commonly used heating and
cooling units using air.
* * * * *