U.S. patent application number 11/194370 was filed with the patent office on 2006-02-09 for refrigerating device comprising waste heat utilization equipment.
This patent application is currently assigned to DENSO Corporation. Invention is credited to Hironori Asa, Shigeru Hisanaga, Atsushi Inaba, Hiroshi Kisita, Takashi Yamanaka, Yasushi Yamanaka.
Application Number | 20060026981 11/194370 |
Document ID | / |
Family ID | 35756054 |
Filed Date | 2006-02-09 |
United States Patent
Application |
20060026981 |
Kind Code |
A1 |
Inaba; Atsushi ; et
al. |
February 9, 2006 |
Refrigerating device comprising waste heat utilization
equipment
Abstract
In a refrigerating device comprising waste heat utilization
equipment having: a refrigerating cycle 200 formed by sequentially
connecting a compressor 210, a condenser 210, an expansion valve
240, and an evaporator 250; and a Rankine cycle 300 formed by
sequentially connecting a heater 310 using the waste heat of a heat
generating device (for example, an internal combustion engine) 10
as a heating source, an expansion device 320, the above-mentioned
condenser 220, and a pump 330, in which the drive shafts of the
compressor 210 and the expansion device 320 are separated from each
other. Then, the output of the expansion device 320 is used mainly
for generating electricity.
Inventors: |
Inaba; Atsushi;
(Kariya-city, JP) ; Yamanaka; Yasushi;
(Nakashima-gun, JP) ; Hisanaga; Shigeru;
(Kariya-city, JP) ; Yamanaka; Takashi;
(Kariya-city, JP) ; Asa; Hironori; (Okazaki-city,
JP) ; Kisita; Hiroshi; (Anjo-city, JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Assignee: |
DENSO Corporation
Kariya-city
JP
Nippon Soken, Inc.
Nishio-shi
JP
|
Family ID: |
35756054 |
Appl. No.: |
11/194370 |
Filed: |
August 1, 2005 |
Current U.S.
Class: |
62/238.6 ;
62/323.1 |
Current CPC
Class: |
F25B 27/02 20130101;
Y02A 30/274 20180101; B60H 1/3222 20130101; B60H 2001/3297
20130101 |
Class at
Publication: |
062/238.6 ;
062/323.1 |
International
Class: |
F25B 27/00 20060101
F25B027/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 3, 2004 |
JP |
2004-227006 |
Claims
1. A refrigerating device comprising waste heat utilization
equipment having: a refrigerating cycle comprising a compressor, a
condenser, an expansion valve, and an evaporator which are
sequentially connected; and a Rankine cycle comprising a heater
using the waste heat of a heating device as a heating source, an
expansion device, the condenser, and a pump, which are sequentially
connected, wherein drive shafts of the compressor and the expansion
device are separated from each other.
2. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 1, wherein the heat generating
device is an internal combustion engine.
3. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 1, wherein output of the expansion
device is used for generating electricity.
4. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 1, wherein output of the expansion
device is used for driving the pump.
5. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 2, wherein the compressor is driven
by the internal combustion engine.
6. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 1, wherein the compressor is driven
by an electric motor.
7. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 2, wherein the compressor is driven
by at least one of the internal combustion engine and the electric
motor.
8. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 1, further comprising an electric
generator driven by the expansion device, a control circuit, and at
least a battery, wherein the control circuit controls the
electricity generation of the electric generator, in accordance
with amount of electric energy stored in the battery by controlling
the rotation speed of the electricity generator.
9. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 2, further comprising at least a
battery and a main electric generator driven by the internal
combustion engine, wherein the main electric generator comprises a
control means for controlling the amount of electricity to be
generated in accordance with amount of electric energy stored in
the battery.
10. The refrigerating device comprising waste heat utilization
equipment as set for in claim 1, wherein the refrigerating device
is mounted on a hybrid vehicle, the hybrid vehicle comprises a
motor generator and at least a battery, and the motor generator
comprises a control means for controlling the amount of electricity
to be generated in accordance with the amount of electric energy
stored in the battery.
11. The refrigerating device comprising waste heat utilization
equipment as set forth in claim 8, wherein the electricity
generation control of the electric generator is carried out by
controlling the rotation speed of an electric motor for driving the
pump.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a refrigerating device
comprising waste heat utilization equipment, for recovering power
by utilizing waste heat of a heat generating device, and is
preferably applied to a vehicle having an internal combustion
engine.
[0003] 2. Description of the Related Art
[0004] As a conventional refrigerating device, for example, one
disclosed in Patent document 1 is known. The refrigerating device
has a Rankine cycle, utilizing cooling waste heat included in a
cooling medium, such as a cooling water, for cooling an internal
combustion engine as a heat generating device, and a refrigerating
cycle, and the output shaft of an expansion device in the Rankine
cycle is connected to the shaft of a compressor in the
refrigerating cycle. Due to this, it is possible to drive the
compressor by using power (output of the expansion device)
recovered in the Rankine cycle and air-conditioning is enabled
while the load imposed on the internal combustion engine is
reduced. [0005] [Patent document 1] Japanese Unexamined Patent
Publication (Kokai) No. 56-43018
[0006] However, in the above-mentioned refrigerating device,
air-conditioning is not possible when waste heat cannot be
recovered such as when an internal combustion engine is in a
warm-up state. For example, in the case where the refrigerating
device is applied to a vehicle, even if the cooling of the vehicle
is required after it has been exposed to the heat of the sun in
summer, and despite a strong demand for air-conditioning, it is not
possible to perform air-conditioning until warm-up of the engine is
completed because the compressor cannot be driven by an expansion
device.
SUMMARY OF THE INVENTION
[0007] The above-mentioned problem being taken into consideration,
the object of the present invention is to provide a refrigerating
device comprising waste heat utilization equipment capable of air
conditioning even if there is no waste heat from a heat generating
device.
[0008] In order to attain the above-mentioned object, the present
invention employs the following technical means.
[0009] In a first aspect of the present invention, a refrigerating
device comprising waste heat utilization equipment having a
refrigerating cycle (200) formed by sequentially connecting a
compressor (210), a condenser (220), an expansion valve (240), and
an evaporator (250) and a Rankine cycle (300) formed by
sequentially connecting a heater (310) using waste heat of a heat
generating device (10) as a heating source, an expansion device
(320), the above-mentioned condenser (220), and a pump (330), is
characterized in that the drive shafts of the compressor (210) and
the expansion device (320) are separated from each other.
[0010] Due to this, it is possible to operate the refrigerating
cycle (200) using the compressor (210) even when the expansion
device (320) cannot be operated because a sufficient amount of
waste heat cannot be obtained from the heat generating device (10)
and, therefore, air-conditioning is possible.
[0011] In a second aspect of the present invention, preferably, an
internal combustion engine (10) is used as the heat generating
device (10).
[0012] In a third aspect of the present invention according to the
first or second aspect, it is preferable to use the output of an
expansion device (320) for generating electricity and, due to this,
it is possible to reduce the load of generating electricity imposed
on an internal combustion engine (10).
[0013] In a fourth aspect of the present invention, it may be
possible to use the output of an expansion device (320) for driving
a pump (330) and, due to this, it is possible to reduce the energy
for driving the pump (330).
[0014] A fifth aspect of the present invention is characterized in
that a compressor (210) is driven by an internal combustion engine
(10) and, due to this, regardless of the presence or absence of the
output of an expansion device (320), it is possible not only to
operate the compressor (210) but also to effectively utilize the
waste heat of the internal combustion engine (10) in accordance
with the output of the expansion device (320).
[0015] In a sixth aspect of the present invention, it may be
possible to drive a compressor (210) by an electric motor (213) or,
in a seventh aspect of the present invention, it may be possible to
drive a compressor (10) by at least one of the internal combustion
engine (10) and the electric motor (213).
[0016] In an eighth aspect of the present invention, the
refrigerating device further comprises an electric generator (321)
driven by the expansion device (320), a control circuit (41), and
at least a battery (40). The control circuit (41) controls the
generation of electricity by the electric generator (321) in
accordance with the amount of electric energy stored in the battery
(40) by controlling the rotation speed of the electric generator
(321).
[0017] According to this aspect, it is also possible to reduce the
load of generating electricity imposed on an internal combustion
engine (10) and, as a result, it is possible to improve the fuel
consumption efficiency of a vehicle as a whole.
[0018] In a ninth aspect of the present invention, the
refrigerating device further comprises at least a battery (40) and
a main electric generator (60) driven by the internal combustion
engine (10). The main electric generator (60) comprises a control
means (61) for controlling the amount of electricity to be
generated in accordance with the amount of electric energy stored
in the battery (40).
[0019] In a tenth aspect of the present invention, the
refrigerating device is mounted on a hybrid vehicle. The hybrid
vehicle comprises a motor generator and at least a battery (40).
The motor generator comprises a control means (61) for controlling
the amount of electricity to be generated in accordance with the
amount of electric energy stored in the battery (40).
[0020] In an eleventh aspect of the present invention according to
the eighth aspect, the electricity generation control of the
electric generator (321) is carried out by controlling the rotation
speed of an electric motor (331) for driving the pump (330).
[0021] The present invention may be more fully understood from the
description of the preferred embodiments of the invention set forth
below, together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In the drawings:
[0023] FIG. 1 is a schematic diagram showing a general view of a
refrigerating device comprising waste heat utilization equipment in
a first embodiment of the present invention.
[0024] FIG. 2 is a schematic diagram showing a general view of a
refrigerating device comprising waste heat utilization equipment in
a second embodiment of the present invention.
[0025] FIG. 3 is a schematic diagram showing a general view of a
refrigerating device comprising waste heat utilization equipment in
a third embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0026] A first embodiment of the present invention is shown in FIG.
1 and a concrete configuration thereof is explained first. In this
embodiment, a refrigerating device comprising waste heat
utilization equipment (hereinafter, referred to as a refrigerating
device) 100 of the present invention is applied to a vehicle using
an engine 10 as a drive source. The refrigerating device 100 is
provided with a refrigerating cycle 200 and a Rankine cycle 300 and
the respective operations of the respective cycles 200 and 300 are
controlled by a control unit, not shown.
[0027] The engine 10 is a water-cooling internal combustion engine
(corresponding to a heat generating device in the present
invention) and a radiator circuit 20 for cooling the engine 10 by
means of circulation of engine cooling water and a heater circuit
30 for heating conditioned air using the cooling water (hot water)
as a heat source, are provided.
[0028] The radiator circuit 20 is provided with a radiator 21 and
the radiator 21 cools the cooling water caused to circulate by a
hot water pump 22 by effecting heat exchange with the outside air.
Here, an electric pump is employed as the hot water pump 22. In the
channel at the outlet of the engine 10 (channel between the engine
10 and the radiator 21), a heater 310 of the Rankine cycle 300,
which will be described later, is arranged and the cooling water is
caused to flow through the heater 310. In the radiator circuit 20,
a radiator bypass channel 23 through which cooling water flows
while bypassing the radiator 21 is provided and a thermostat 24
adjusts the flow rate of cooling water flowing through the radiator
21 and the flow rate of cooling water flowing through the radiator
bypass channel 23.
[0029] In the heater circuit 30, a heater core 31 is provided and
the above-mentioned hot water pump 22 circulates cooling water (hot
water). The heater core 31 is arranged in an air conditioning case
410 of an air conditioning unit 400 and heats conditioned air
supplied by a fan 420 by effecting heat exchange with hot water.
Further, the heater core 31 is provided with an air mix door 430
and the flow rate of conditioned air flowing through the heater
core 31 is changed by opening/closing the air mix door 430.
[0030] The refrigerating cycle 200 comprises, as is well known, a
compressor 210, a condenser 220, a receiver 230, an expansion valve
240, and an evaporator 250, and a closed circuit is formed by
sequentially connecting these components. The compressor 210 is a
fluid device for compressing a refrigerant in the refrigerating
cycle 200 to a high-temperature and high-pressure state and is
driven by the drive force of the engine 10. In other words, to the
drive shaft of the compressor 210, a pulley 211 is fixed as a drive
means, the drive force of the engine 10 is transferred to the
pulley 211 via a belt 11, and thus the compressor 210 is driven.
The pulley 211 is provided with an electromagnetic clutch 212 for
intermittently connecting the compressor 210 and the pulley 211.
The intermittent connection therebetween, by the electromagnetic
clutch 212, is controlled by a control unit, not shown.
[0031] The condenser 220 is a heat exchanger connected to the
outlet of the compressor 210 for condensing and liquefying the
refrigerant by effecting heat exchange with outside air. The
receiver 230 is a receiver for separating the refrigerant condensed
by the condenser 220 into a gas-liquid two-phase, that is, gas and
liquid, and causes only the liquefied refrigerant separated here to
flow out toward the expansion valve 240. The expansion valve 240
reduces in pressure, and expands, the liquefied refrigerant from
the receiver 230 and, in the present embodiment, a
temperature-sensitive expansion valve is employed that reduces in
pressure the refrigerant isenthalpically and controls the throttle
opening degree so that the degree of superheat of the refrigerant
sucked by the compressor 210 is a predetermined value.
[0032] The evaporator 250, which is arranged in the air
conditioning case 410 of the air conditioning unit 400, similarly
to the heater core 31, is a heat exchanger for cooling conditioned
air from the fan 420 by using latent heat produced when the
refrigerant that has been reduced in pressure and expanded is
evaporated by the expansion valve 240. Then, the refrigerant outlet
of the evaporator 250 is connected to the suction side of the
compressor 210. The ratio of the conditioned air cooled by the
evaporator 250 to the conditioned air heated by the heater core 31
is changed in accordance with the opening degree of the air mix
door 430 and the temperature is adjusted to a temperature set by a
passenger.
[0033] On the other hand, the Rankine cycle 300 recovers waste heat
energy produced by the engine 10 (thermal energy of cooling water)
and utilizes the waste heat energy by converting it into electric
energy. The Rankine cycle 300 is explained below.
[0034] The Rankine cycle 300 comprises the heater 310, an expansion
device 320, the condenser 220, the receiver 230, and a pump 330 and
a closed circuit is formed by sequentially connecting these
components. The operative fluid flowing through the Rankine cycle
300 is the same as the refrigerant in the above-mentioned
refrigerating cycle 200 and the condenser 220 and the receiver 230
used in the refrigerating cycle 200 are also used here.
[0035] The pump 330 is an electric pump using an electric motor 331
operated by a control unit, not shown, as a drive source and
circulates the refrigerant in the Rankine cycle 300. The heater 310
is a heat exchanger for heating the refrigerant by effecting heat
exchange between the refrigerant sent from the pump 330 and the hot
cooling water flowing through the radiator circuit 20. The
expansion device 320 is a fluid device for generating a rotational
drive force by the expansion of the superheated steam refrigerant
heated by the heater 310. The refrigerant discharged from the
expansion device 320 flows up to the condenser 220 and the receiver
230 described above.
[0036] In the present invention, the drive shaft of the expansion
device 320 and the drive shaft of the compressor 210 are completely
separated and an electric generator 321 is connected to the
expansion device 320. Then, as described later, the electric
generator 321 is operated by the drive force of the expansion
device 320 and the electric power generated by the electric
generator 321 is used to charge a battery 40 via a control circuit
41.
[0037] Next, the operation, the function and the effect of the
above-mentioned configuration are explained below.
[0038] 1. Stand-Alone Operation of Refrigerating Cycle
[0039] When waste heat cannot be obtained during warm-up
immediately after the engine 10 is started, etc., the electric
motor 331 of the pump 330 is stopped (the expansion device 320 is
stopped), the electromagnetic clutch 212 is connected, the
compressor 210 is driven by the drive force of the engine 10, and
the refrigerating cycle 200 is operated stand-alone. In this case,
the operation is the same as that of a normal air conditioner for a
vehicle.
[0040] 2. Stand-Alone Operation of Rankine Cycle
[0041] When an air conditioner is not required to operate and a
sufficient amount of waste heat of the engine 10 is obtained, the
electromagnetic clutch 212 is disconnected (the compressor 210 is
stopped), the electric motor 331 (pump 330) is operated, and the
Rankine cycle 300 is operated, stand-alone, to generate
electricity.
[0042] In this case, the pressure of the liquid refrigerant in the
receiver 230 is increased by the pump 330, and the liquid
refrigerant is sent to the heater 310, then is heated by the hot
engine cooling water in the heater 310, and is turned into a
superheated steam refrigerant, which is then sent to the expansion
device 320. In the expansion device 320, the superheated steam
refrigerant is expanded and reduced in pressure isentropically, and
part of the thermal energy and the pressure energy thereof is
converted into a rotational drive force. The electric generator 321
is operated by the rotational drive force taken out in the
expansion device 320 and then the electric generator 321 generates
electricity. Then, the electric power generated by the electric
generator 321 is used to charge up the battery 40 via the control
circuit 40 and is used to operate various auxiliary devices. The
refrigerant reduced in pressure in the expansion device 320 is
condensed in the condenser 220, separated into gas and liquid in
the receiver 230, and then sucked by the pump 330 again.
[0043] The control circuit 41 controls the rotation speed of the
electric generator 321 and thus controls the generation of
electricity by the electric generator 321 in accordance with the
amount of electric energy stored in the battery 40. Due to this, it
is possible to convert the power obtained in the Rankine cycle into
electric energy and to store it in the battery 40 in an optimum
form and, further, to reduce the load of an electricity generation
means (for example, an alternator) 60 driven by an engine, which is
a drive source for operating a vehicle, in accordance with the
amount of electricity stored in the battery 40, and thus, to
improve the fuel consumption efficiency of a vehicle as a
whole.
[0044] The alternator 60 comprises a control means 61 such as a
regulator that controls the amount of electricity to be generated
in accordance with the amount of electric energy stored in the
battery 40.
[0045] 3. Simultaneous Operation of Refrigerating Cycle and Rankine
Cycle
[0046] When an air conditioner is required to operate and a
sufficient amount of waste heat is available, the refrigerating
cycle 200 and the Rankine cycle 300 are operated simultaneously and
both air conditioning and electricity generation are carried
out.
[0047] In this case, the electromagnetic clutch 212 is connected
and the electric motor 331 (the pump 330) is operated. Both the
cycles 200 and 300 share the condenser 220 and the refrigerant flow
branches in the receiver 230 and circulates through the respective
channels. The operation of each of the cycles 200 and 300 is the
same as that in the case of the stand-alone operation described
above.
[0048] Due to this, even when a sufficient amount of waste heat of
the engine 10 cannot be obtained and the expansion device 320
cannot be operated, the operation of the refrigerating cycle 200
becomes possible, because the compressor 210 is separated from the
expansion device 320, and air conditioning can be carried out.
[0049] Then, when a sufficient amount of waste heat of the engine
10 can be obtained, regardless of the operation state of the
refrigerating cycle 200, electricity generation becomes possible by
utilizing the waste heat of the engine 10, the load of generating
electricity imposed on the engine 10 (the load to operate the
alternator) can be reduced, and thus the fuel consumption
efficiency can be improved.
Second Embodiment
[0050] A second embodiment of the present invention is shown in
FIG. 2. In the second embodiment, the drive means of the compressor
210 in the first embodiment is modified. In other words, here, the
compressor 210 is connected to an electric motor 213 (that is, the
compressor is an electric compressor) and is driven by the drive
force of the electric motor 213. Due to this, the same effect as
that in the first embodiment can be obtained.
[0051] The compressor 210 may be a hybrid compressor capable of
selecting at least one of the engine 10 and the electric motor 213
as a drive means.
Third Embodiment
[0052] A third embodiment of the present invention is shown in FIG.
3. In the third embodiment, the drive source of the pump 330 in the
first embodiment is modified. Here, instead of the electric motors
321 in the first and second embodiments, an electric generator 322
having both functions of an electric motor and an electric
generator is connected to the expansion device 320, and further,
the pump 330 and the electric generator 322 are connected to each
other.
[0053] In the third embodiment, when the Rankine cycle is operated,
first the electric generator 322 is operated as an electric motor
to drive the pump 330. Then, when a sufficient amount of waste heat
can be obtained from the engine 10 and the drive force of the
expansion device 320 exceeds the power of the pump 330, the
electric-motor driven electric generator 322 is operated as an
electric generator to generate electricity.
[0054] Due to this, the dedicated drive source (the electric motors
331 in the above-mentioned first and second embodiments) for
driving the pump 330 can be dispensed with, the configuration can
be simplified and the energy for driving the pump 330 can be
reduced.
Other Embodiments
[0055] In the first to third embodiments, the engine (internal
combustion engine) 10 for a vehicle is used as a heat generating
device, but the heat generating device is not limited to this and
any device, such as an external combustion engine, a fuel cell
stack for a fuel cell powered vehicle, various motors, and an
inverter, which produces heat during operation and wastes part of
the heat (waste heat is produced) for a temperature control of the
device can be applicable.
[0056] The alternator comprising a regulator is taken as an example
of an electricity generation means driven by the drive source for
operating a vehicle in accordance with the amount of electric
energy stored in the battery, but the present invention is not
limited to this and it may be possible to provide a control means
for controlling a motor generator mounted on a hybrid vehicle, in
accordance with the amount of electric energy stored in the
battery.
[0057] As another method for carrying out the electricity
generation control of the electric generator 321, it may be
possible to control the electricity generation of the electric
generator 321 by controlling the rotation speed of the electric
motor 331 for driving the pump 330.
[0058] While the invention has been described by reference to
specific embodiments chosen for the purposes of illustration, it
should be apparent that numerous modifications could be made
thereto, by those skilled in the art, without departing from the
basic concept and scope of the invention.
* * * * *