U.S. patent application number 10/211460 was filed with the patent office on 2003-03-06 for gas heat pump type air conditioning device.
Invention is credited to Kasagi, Tsukasa, Kunita, Hiraku, Yamagishi, Kazuo.
Application Number | 20030041609 10/211460 |
Document ID | / |
Family ID | 19091441 |
Filed Date | 2003-03-06 |
United States Patent
Application |
20030041609 |
Kind Code |
A1 |
Kasagi, Tsukasa ; et
al. |
March 6, 2003 |
Gas heat pump type air conditioning device
Abstract
In order to provide a gas heat pump type air conditioning device
in which accessibility and maintenance operation are not disturbed
due to snow in snowy areas, a gas heat pump type air conditioning
device comprises a compression device for which the driving source
is a gas engine and forms a refrigerating cycle by circulating a
refrigerant, a bypass pipe channel section which is provided around
space where an outdoor unit is installed and is separated from an
engine-coolant-water system of the gas engine via a channel change
switching device, wherein waste heat exhausted from the gas engine
is collected back into the engine-coolant-water, and the
refrigerant is heated by the engine-coolant-water so as to enhance
air heating capacity.
Inventors: |
Kasagi, Tsukasa; (Ama-gun,
JP) ; Kunita, Hiraku; (Nishi-kasugai-gun, JP)
; Yamagishi, Kazuo; (Yokohama-shi, JP) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
19091441 |
Appl. No.: |
10/211460 |
Filed: |
August 5, 2002 |
Current U.S.
Class: |
62/238.7 ;
62/323.1 |
Current CPC
Class: |
F25B 41/20 20210101;
F25B 13/00 20130101; F25B 2313/0213 20130101; Y02T 10/12 20130101;
F25B 27/00 20130101; F25B 2327/00 20130101; F25B 2313/023 20130101;
F01N 5/02 20130101; Y02B 30/52 20130101; F25B 2313/02523 20130101;
F25B 2313/0253 20130101 |
Class at
Publication: |
62/238.7 ;
62/323.1 |
International
Class: |
F25B 027/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 31, 2001 |
JP |
P2001-264910 |
Claims
What is claimed is:
1. A gas heat pump type air conditioning device comprising: a
compression device having a gas engine driving source and forming a
refrigerating cycle by circulating a refrigerant; a bypass pipe
channel section which is provided around a space where an outdoor
unit is installed and is divided from an engine-coolant-water
system of the gas engine via a channel change switching device;
wherein waste heat exhausted from the gas engine is collected back
into the engine-coolant-water, and the refrigerant is heated by the
engine-coolant-water so as to enhance air heating capacity.
2. A gas heat pump type air conditioning device according to claim
1, wherein the bypass pipe channel section is divided after the
refrigerant is cooled by the engine coolant water.
3. A gas heat pump type air conditioning device according to claim
1, wherein a heating device which heats exhaust gas which is
exhausted from the gas engine and increases the amount of thermal
energy collectable in an exhaust gas heat exchanging device.
4. A gas heat pump type air conditioning device according to claim
3, wherein the heating device is a combusting device for heating
exhaust gas which supplies the exhaust gas generated by combusting
fuel in the combusting device to the exhaust gas.
5. A gas heat pump type air conditioning device according to claim
4, wherein the combusting device of the combusting device for
heating exhaust gas is provided in the exhaust gas heat exchanging
device.
6. A gas heat pump type air conditioning device according to claim
4, wherein a catalyst container which contains exhaust gas cleaning
catalyst is provided in a exhaust system which connects the gas
engine and the exhaust gas heat exchanging device, and a combustor
of combusting device for heating exhaust gas is provided in the
catalyst container.
7. A gas heat pump type air conditioning device according to claim
1, wherein the bypass channel which is provided with the channel
change switching device in the engine coolant water system in the
downstream of the gas engine is formed, and the engine coolant
water heating device is provided in the bypass channel.
8. A gas heat pump type air conditioning device according to claim
4, wherein the heating device combusts the same gas fuel as the gas
engine and heats the gas fuel.
9. A gas heat pump type air conditioning device according to claim
3, wherein the heating device operates when outdoor air temperature
detecting device (74) detects temperature lower than a
predetermined value.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a gas heat pump type air
conditioning device in which a compression device for circulating a
refrigerant is driven by a gas engine as a driving source, and the
invention particularly relates to a gas heat pump type air
conditioning device which does not obstruct maintenance of the
outdoor unit due to snow.
[0003] 2. Description of Related Art
[0004] An air conditioning device which performs air conditioning
such as air cooling and air heating by using a heat pump is
provided with a refrigerant circuit including components such as an
indoor heat exchanger, a compression device, an outdoor heat
exchanger, and a throttling structure. Air cooling and heating
indoors is realized by exchanging heat of indoor air and outdoor
air by the indoor heat exchanger and the outdoor heat exchanger
during the circulation of a refrigerant. Also, in this refrigerant
circuit, the receipt of heat during air heating does not rely on
only the outdoor heat exchanger, and a refrigerant heating device
may sometimes be provided for directly heating the refrigerant.
[0005] Recently, regarding a driving source for the compression
device which is provided in the above refrigerant circuit, a
driving source employing a gas engine has been developed to replace
electric motors which are commonly used. This air conditioning
device employing a gas engine is generally called a gas heat pump
type air conditioning device (hereinafter called a GHP). By this
GHP, because municipal gas or the like which are relatively
inexpensive, can be used as fuel, running costs do not increase
because it is different from an electric heat pump provided with
compression device using electric motors (hereinafter called EHP);
therefore cost can be reduced for consumers.
[0006] Also, in a GHP, outstanding air heating effects can be
achieved if so-called waste heat such as high temperature exhaust
gas exhausted from a gas engine or heat of engine-coolant-water is
used as a heat source for the refrigerant during air heating
operations, and more efficient use of energy is possible as
compared with an EHP (electric heat pump). In addition, in this
case, the efficiency percentage of energy use of the GHP is 1.2 to
1.5 times higher compared to an EHP. Also, the apparatuses above,
such as a refrigerant heating device, are not necessarily to be
installed in the refrigerant circuit if this kind of structure is
used.
[0007] Additionally, in a GHP, defrosting operations necessary for
the outdoor heat exchanging device in air heating can be performed
by using the exhaust heat of the gas engine. Generally, the
defrosting operation in an EHP is done in such a way that the air
heating operation stops and the air cooling operation is
temporarily performed to defrost the outdoor heat exchanging
device. In this case, because cold air flows into the room,
comfortableness inside the room is deteriorated. In contrast, in a
GHP, continuous air heating operation is possible because of the
above condition, and problems occuring in the case of an EHP do not
arise.
[0008] As mentioned above, in a GHP, the exhaust heat such as high
temperature exhaust gas exhausted from gas engines or waste heat of
engine-coolant-water is introduced to a heat exchanging device such
as an exhausted gas heat exchanging device or water heat exchanging
device during air heating operation; thus, collecting exhaust heat
is possible by using such exhaust heat as a heat source for the
refrigerant, outstanding air heating capacity can be obtained
differently from EHP.
[0009] According to this, GHP is attention because the GHP is
provided with sufficient air heating capacity even in snowy areas
where outdoor air temperature is low in winter.
[0010] However, in the conventional GHP, because it is common for
an outdoor unit to be installed outside of the room, there is a
problem in snowy areas in that the snow around the outdoor unit
hinders access to it for the purpose of maintenance.
[0011] Also, an outdoor unit is installed on a foundation made of
concrete with anchor bolts; however, if the height of the
foundation is determined so that the door for maintenance can be
opened with a certain amount of snow there, the height of the
foundation may be higher as compared with the case of areas without
much snow, thus that is a problems such as increase in cost.
SUMMARY OF THE INVENTION
[0012] This invention was made in consideration of the above
conditions. Thus, an object of this invention is to provide a gas
heat pump type air conditioning device so that accessibility and
operations for maintenance will not be disturbed due to snow in
snowy areas.
[0013] In order to solve the above problems, the invention has the
following construction.
[0014] In a gas heat pump type air conditioning device according to
the first aspect of this invention, a refrigerating cycle is formed
by circulating the refrigerant by a compression device for which
the driving source is a gas engine, waste heat exhausted from the
gas engine is collected in engine-coolant-water, and the
refrigerant is heated by the engine-coolant-water in order to
enhance the heating capacity, a bypass pipe channel section is
branched from an engine coolant water system of the gas engine by
way of a channel change switching device, and the bypass pipe
channel section is embedded in proximity to where an outdoor unit
is installed.
[0015] In the gas heat pump type air conditioning device according
to the first aspect of present invention, a bypass pipe channel
section which is branched from an engine coolant water system of
the gas engine by way of a channel change switching device is
provided, and the bypass pipe channel section is embedded in
proximity to where an outdoor unit is installed; thus if engine
coolant water is introduced to the bypass pipe channel section
according to necessity, it is possible to heat the space around the
outdoor unit to melt snow.
[0016] In such a gas heat pump type air conditioning device, the
bypass pipe channel section should preferably be branched after the
refrigerant is cooled by the engine coolant water. By doing this,
waste heat of engine coolant water can be used effectively after
excellent air heating capacity is obtained by heating the
refrigerant.
[0017] In the gas heat pump type air conditioning device according
to the first or the second aspect of the present invention, a
heating device which heats exhaust gas which is exhausted from the
gas engine and increases the amount of thermal energy collectable
in an exhaust gas heat exchanging device should preferably be
provided. By doing this, it is possible to enhance air heating
capacity and to enhance the snow melting capacity by waste
heat.
[0018] As a heating device in this case, a combusting device for
heating exhaust gas which supplies the combustion gas generated by
combusting fuel by the combustor to the combustion gas is
preferable. This combustor of a combusting device for heating
exhaust gas may be provided in the combustion gas heat exchanging
device, or it is also possible that the catalyst container which
contains exhaust gas cleaning catalyst is provided in the fuel
system which connects the gas engine and the exhaust gas heat
exchanging device so that the combustor should be provided inside
this catalyst container
[0019] In the gas heat pump type air conditioning device according
to the first and the second aspect of the present invention, it is
preferable that the bypass channel which is provided with the
channel change switching device in the engine coolant water system
in the downstream of the gas engine is formed, and the heating
device for engine coolant water is provided in the bypass channel.
By doing this, it is possible to enhance air heating capacity and
snow melting capacity by waste heat.
[0020] The heating device should combust and heat the same gas fuel
as the case of the gas engine, and more preferably the gas fuel is
municipal gas.
[0021] Also, the heating device should preferably operate when an
outdoor air temperature detecting device detects a temperature
lower than a predetermined value.
[0022] A gas heat pump type air conditioning device has the
following effects.
[0023] According to the first aspect of present invention, a bypass
pipe channel section which is branched from an engine coolant water
system of the gas engine by way of a channel change switching
device is provided, the bypass pipe channel section is embedded in
proximity to where an outdoor unit is installed, and thus if the
engine coolant water is introduced into the bypass pipe channel
section according to necessity, it is possible to heat the
peripheral area where the outdoor unit is provided to melt snow.
Because of this, it is easy to secure the accessibility to the
outdoor unit and the space for maintenance when it snows.
[0024] By providing the heating device for heating the exhaust gas
during low outdoor air temperature and the heating device for
heating the engine coolant water, it is possible to increase air
heating capacity and the capacity for melting snow by using waste
heat.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 shows the first embodiment of gas heat pump type air
conditioning device during air heating operation according to the
present invention.
[0026] FIG. 2 shows the first embodiment of gas heat pump type air
conditioning device during air cooling operation according to the
present invention.
[0027] FIG. 3a and 3b show an example of disposition of the group
of bypass pipe channel around the outdoor unit in front view and in
plan view.
[0028] FIG. 4 shows the second embodiment of gas heat pump type air
conditioning device during air heating operation according to the
present invention.
[0029] FIG. 5 shows an important part of the first example of the
second embodiment of the combusting device for heating exhaust gas
in the present invention.
[0030] FIG. 6 shows an important part of the second example of the
second embodiment of the combusting device for heating exhaust gas
in the present invention.
[0031] FIG. 7 shows an important part of the third example of the
second embodiment of the combusting device for heating exhaust gas
in the present invention.
[0032] FIG. 8 shows the third embodiment of a gas heat pump type
air conditioning device during air heating operation according to
the present invention.
[0033] FIG. 9 is an enlarged view of the heating device of the
third embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0034] An embodiment of a gas heat pump type air conditioning
device (hereinafter called a GHP) according to present invention is
explained with reference to drawings as follows.
[0035] First Embodiment
[0036] FIG. 1 is a system diagram showing an overall construction
of an air heating system of a GHP as a first embodiment of the
present invention. This drawing generally shows an indoor unit 1
and an outdoor unit 10 provided with device such as a compression
device for driving the gas engine. In addition, one or a plurality
of indoor unit 1 and outdoor unit 10 are connected by refrigerant
pipe 2 in such a way that the refrigerant can circulate.
[0037] The indoor unit 1 is provided with an indoor heat exchanging
device 1a which functions as an evaporator which evaporates the low
temperature low pressure liquid refrigerant so as to remove heat
from indoor air (indoor atmosphere) during air cooling operation
and functions as a condenser which condenses the high temperature
high pressure gas refrigerant so as to heat the indoor air during
air heating operation. In addition, throttling structure 1b is
provided per indoor heat exchanging device 1a.
[0038] The outdoor unit 10 is internally divided into two major
sections.
[0039] The first major section is a section forming a refrigerant
circuit primarily by equipment such as a compression device and
outdoor heat exchanging device together with the indoor unit 1, and
the first major constructing section is called hereinafter the
"refrigerant circuit section".
[0040] The second major section is a section provided with
equipment such as a gas engine for driving the compression device
together with auxiliary equipment, and the second major section is
called hereinafter the "gas engine section".
[0041] In the refrigerant circuit section, equipment such as
compression device 11, outdoor heat exchanging device 12, water
heat exchanging device 13, accumulator 14, receiver 15, oil
separator 16, throttling construction 17, 4-way valve 18, solenoid
valve 19, check valve 20, and control valve 21 are provided.
[0042] A compression device 11 is operated by a gas engine GE as a
driving source (which is to be described later), and the
compression device 11 compresses the low temperature low pressure
gas refrigerant taken from any one of indoor heat exchanging device
1a or outdoor heat exchanging device 12 and discharges as high
temperature high pressure gas refrigerant. By this construction,
the refrigerant can radiate the heat to the outdoor air through the
outdoor heat exchanging device 12 during air cooling operation even
if the outdoor air temperature is high. Also, the refrigerant can
give heat to indoor air through the indoor heat exchanging device
12 during air heating operation.
[0043] The outdoor heat exchanging device 12 functions as a
condenser which condenses the high temperature high pressure gas
refrigerant and radiates heat to the outdoor air during the air
cooling operation, and in contrast, the outdoor heat exchanging
device 12 functions as an evaporator which evaporates the low
temperature low pressure liquid refrigerant and removes heat from
outdoor air temperature during the air heating operation. That is,
the outdoor heat exchanging device 12 performs a reverse operation
to the above indoor heat exchanging device 1a during air cooling
operation and air heating operation.
[0044] Also, the outdoor heat exchanging device 12 is provided
neighboring radiator 33 of the gas engine GE (which is described
later). The radiator 33 is a heat exchanging device which
refrigerates the engine-coolant-water of the gas engine GE by
exchanging heat with outdoor air.
[0045] Accordingly, in the case of an air heating operation, when
the outdoor air temperature is low, for example, the indoor heat
exchanging device 12 which functions as an evaporator can exchange
heat between the outdoor air which passed the radiator 33 and was
heated by selectively changing the rotating direction of the
outdoor unit fan 22, and the evaporating capacity can be
enhanced.
[0046] The water heat exchanging device 13 provided in order that
the refrigerant can collect heat from the engine-coolant-water of
the gas engine GE (which is mentioned later). That is, in the air
heating operation, the refrigerant does not rely only on the
exchange of heat in the indoor heat exchanging device 12, and it
becomes possible to collect waste heat from the
engine-coolant-water of the gas engine GE; thus, the effect of air
heating operation can be enhanced.
[0047] Accumulator 14 is provided in order to store the liquid
contained in the gas refrigerant flowing into the compression
device 11.
[0048] Receiver 15 is provided in order to separate the refrigerant
liquefied by the heat exchanging device which functions as a
condenser into air and liquid, and to store the surplus refrigerant
as liquid in the refrigerating cycle.
[0049] Oil separator 16 is provided in order to separate the oil
content contained in the refrigerant and to return the refrigerant
back to the compression device 11.
[0050] Throttling construction 17 is provided in order to reduce
the pressure of condensed high temperature high pressure liquid
refrigerant and to expand the liquid refrigerant so as to produce
low temperature low pressure liquid refrigerant. In an example in
the drawing, a constant pressure expansion valve, thermostatic
expansion valve, and capillary tube are selectively used as a
throttling construction 17 according to the purpose.
[0051] 4-way valve 18 is provided on the refrigerant pipe 2 in
order to selectively change the channel of refrigerant and the
direction of flow. On this 4-way valve 18, four ports such as D, C,
S and E are provided. Port D is connected to the discharging side
of the compression device 11 by the refrigerant pipe 2. Port C is
connected to the outdoor heat exchanging device 12 by the
refrigerant pipe 2. Port S is connected to the absorbing side of
the compression device 11 by the refrigerant pipe 2. Port E is
connected to the indoor heat exchanging device 1a by the
refrigerant pipe 2.
[0052] On the other hand, in the gas engine section, a coolant
water system 30, a fuel absorbing system 60, exhaust gas system,
and an engine oil system (which are not shown in the drawing) are
provided where the gas engine GE is provided in the center
thereof.
[0053] The gas engine GE is connected to a compression device 11
which is provided in the refrigerant circuit by a shaft, a belt and
the like; thus, the driving force is conducted from the gas engine
GE to the compression device 11.
[0054] The coolant water system 30 is provided with a water pump
31, reservoir tank 32, a radiator 33 and the like. This coolant
water system 30 chills the gas engine GE by the
engine-coolant-water which circulates in the circuit shown by a
dashed line organized by connecting these elements by pipes. A
water pump 31 is provided for circulating the coolant water of the
gas engine GE in the circuit. A reservoir tank 32 is provided for
storing the surplus of the coolant water flowing in this circuit
temporarily, and for supplying the surplus to the circuit in case
the coolant water is in short supply. A radiator 33 is constructed
integrally with an outdoor heat exchanging device 12. The radiator
33 is provided for radiating the heat which the
engine-coolant-water removes from the gas engine GE to outdoor
air.
[0055] In the coolant water system 30, in addition to the above
elements, an exhaust gas heat exchanging device 34 is provided.
This exhaust gas heat exchanging device 34 is provided for
collecting the heat of exhaust gas exhausted from the gas engine GE
to the engine-coolant-water. Also, in the coolant water system 30,
a water heat exchanging device 13 (which was mentioned
hereinbefore) is disposed in such a way that the coolant water
system 30 spans two systems such as the refrigerant circuit section
and the coolant water system 30. Therefore the total construction
of the coolant water system 30 is such that the
engine-coolant-water not only removes heat from the gas engine GE
but also collects heat from exhaust gas during air heating
operation; thus, the collected heat is given to the refrigerant
from the engine-coolant-water through the water heat exchanging
device 13.
[0056] Additionally, flow control of engine-coolant-water in the
coolant water system 30 is performed by flow control valves 35A and
35B provided in two places.
[0057] A fuel absorbing system 60 is provided with a gas regulator
61, a gas solenoid valve 62, a gas connection port 63 and the like.
This fuel absorbing system 60 is a system for supplying the
municipal gas such as liquefied natural gas (LNG) as gas fuel to
the gas engine GE. A gas regulator 61 is provided for adjusting the
delivery pressure of gas fuel which is supplied externally via a
gas solenoid valve 62 and a gas connection port 63. The gas fuel
for which the pressure is adjusted by this gas regulator 61 is
supplied to a combustion chamber of the gas engine GE after being
mixed with the air absorbed from the absorbing port (not shown in
the drawing).
[0058] In the GHP of the present invention, the bypass pipe channel
section 80 which is branched from the engine coolant water system
30 of the gas engine GE is provided. This bypass pipe channel
section 80 is embedded around the space where the outdoor unit 1 is
installed after branching from the coolant water system 30 by way
of the flow control valve 81 (a channel change switching device),
and the bypass pipe channel section 80 joins the coolant water
system 30 again.
[0059] The point of the separation of the bypass pipe channel
section 80 is in the downstream of the water heat exchanging device
13 so that the engine coolant water (warm water) after the
refrigerant is heated is introduced therein. This is for the
purpose of reusing the thermal energy retained by the engine
coolant water after the refrigerant is heated, and in addition, the
purpose is to secure the amount of heat for heating the refrigerant
in the water heat exchanging device 13. The junction where the
bypass pipe channel section 80 returns to the coolant water system
30 may be in appropriate points on the pipe channel between the
flow control valve 81 and the water pump 31, and the check valve 82
should preferably be provided to prevent the back flow.
[0060] The flow control valve 81 may be preferable if it can adjust
the incoming flow to the bypass pipe channel section 80 and the
incoming flow directly to the water pump 31 based on the divergence
of the valve. Also the pipe channel should preferably be changed
simply and selectively by a three way valve or a combination of a
plurality of switch valves, or the like.
[0061] Additionally, the flow control valve 81 may be preferably
operated after receiving the control signal outputted from a manual
switch (not shown in the drawing) or sensors for detecting snow and
temperature.
[0062] The bypass pipe channel section 80 is embedded as a group of
pipes 80a which are disposed around the rack of the outdoor unit 10
(for example a foundation made of reinforced concrete) or
underground by appropriate density after the bypass pipe channel 80
emerges from the outdoor unit 10 as shown in FIG. 3. Although the
area for embedding this bypass pipe channel section 80 should
preferably be as large as possible, there are limits such as amount
of heat of engine coolant water which can be used. Therefore the
area for embedding this bypass pipe channel section 80 can be
preferably and selectively determined by factors such as
accessibility to the outdoor unit 10, space for maintenance, space
for installing each device, the construction of outdoor unit 10,
and amount of heat which can be used.
[0063] In the example shown in the drawings, although the bypass
pipe channel section 80 is one system, it is possible to branch the
bypass pipe channel section 80 into an appropriate plurality of
sections by making headers, or it is also possible to provide
switch valves according to necessity to enable the respective flow.
Furthermore, the disposition of the group of pipes 80a is not
limited to the case as shown in the drawings; thus, the most
preferable disposition may be selectively determined in
consideration of factors such as temperature and pressure loss.
[0064] In the following paragraphs, regarding the GHP, a typical
way of performing the method of air cooling and air heating for the
indoor environment is explained by describing the flow of the
refrigerant and the engine-coolant-water.
[0065] First, the operating method of the air heating operation is
explained with reference to FIG. 1. Regarding the description of
the valves, if a valve in the drawing is filled in black, the valve
is open. The directions of the flow of the refrigerant and the
engine-coolant-water are shown by arrows.
[0066] In this case, in a 4-way valve 18 of the refrigerant
circuit, the interval between the port D and the port E, and the
interval between the port C and the port S are connected. The
discharging side of the compression device 11 is connected to the
indoor heat exchanging device 1a. In such a condition, high
temperature high pressure gas refrigerant discharged from the
compression device 11 is sent to the indoor heat exchanging device
1a through the 4-way valve 18 and the operating valve 21.
[0067] High temperature high pressure gas refrigerant exchanges
heat with the indoor air in the indoor heat exchanging device 1a to
be liquefied. In this process, the gas refrigerant radiates heat to
heat the indoor air, and after that, the gas refrigerant becomes
high temperature high pressure liquid refrigerant. This liquid
refrigerant flows passing through a throttling construction 1b, an
operating valve 21 and a receiver 15, and consequently this liquid
refrigerant is separated into gas and liquid content.
[0068] The liquid refrigerant discharged from the receiver 15 is
introduced to the refrigerant pipe 2 which is branched, either
portion of which is sent to the water heat exchanging device 13 via
the throttling construction 17a of the constant pressure expansion
valve. The other liquid refrigerant is sent to the outdoor heat
exchanging device 12 through the solenoid valve 18 which is made to
open and the throttling construction 17b of the thermal expansion
valve.
[0069] The pressure of liquid refrigerant sent to the water heat
exchanging device 13 is reduced by passing through the throttling
construction 17a; thus, the liquid refrigerant becomes low
temperature low pressure refrigerant. In the water heat exchanging
device 13, low temperature low pressure liquid refrigerant is
evaporated by absorbing heat from the engine-coolant-water, thus
becoming low temperature low pressure gas refrigerant. At this
time, if high temperature engine-coolant-water flows in the
radiator 33, the liquid refrigerant can be evaporated efficiently
by the engine waste heat.
[0070] In addition, regarding the water heat exchanging device 13
and the outdoor heat exchanging device 12 for evaporating the
liquid refrigerant, either one can be chosen favorably according to
the operating conditions such as outdoor air temperature. Also the
combined use is possible according to the construction of the
device.
[0071] Such a refrigerant which becomes low temperature low
pressure gas is introduced to the accumulator 14 from the port C of
4-way valve 18 via the port S, the gas and liquid content of the
refrigerant are separated, and are then taken into the compression
device 11. The gas refrigerant taken into the compression device 11
is compressed by the operation of the compression device 11 to
become high temperature high pressure gas refrigerant, and is sent
to the indoor heat exchanging device 1a again; thus, the
refrigerating cycle, in which the refrigerant repeatedly changes
state, can be formed.
[0072] In such air heating operation, in order to prevent the snow
from accumulating around the outdoor unit 10, or to melt the snow,
the engine coolant water flowing from the water heat exchanging
device 13 is supplied to the bypass pipe channel section 80 by
operating the flow control valve 81. Although the temperature of
this engine coolant water is decreased by heating the refrigerant
in the water heat exchanging device 13, this engine coolant water
is still warm water retaining substantial amounts of heat.
Therefore, preventing the snow from accumulating and melting the
snow by heating around the group of pipe 80a by the flow of this
warm water through the group of pipes 80a are possible. That is, it
is possible to prevent the snow from accumulating around the
outdoor unit 10 and melting the snow by collecting waste heat of
the gas engine GE from the engine coolant water.
[0073] Next, the flow of the refrigerant and the
engine-coolant-water in air cooling operation is explained briefly
with reference to the FIG. 2.
[0074] In this case, in a 4-way valve 18, spaces are connected
between the port D and the port C, and between the port E and the
port S. The discharging side of the compression device 11 is
connected to the outdoor heat exchanging device 12. In this
condition, the high temperature high pressure gas refrigerant
discharged from the compression device 11 is sent to the indoor
heat exchanging device 12 which functions as a condenser through
the 4-way valve 18.
[0075] The high temperature high pressure gas refrigerant is
evaporated in the outdoor heat exchanging device 12 to discharge
heat to outdoor air; thus, the refrigerant becomes high temperature
high pressure liquid refrigerant. This liquid refrigerant is
introduced to the receiver 15 through the check valve 20. The
liquid refrigerant separated into air and liquid components in the
receiver 15 is introduced to the throttling construction 1b through
the operating valve 21; then, the pressure is reduced in the
process of passing through the throttling construction 1b,
resulting in low temperature low pressure liquid refrigerant, then
the liquid refrigerant is sent to the indoor heat exchanging device
1a which functions as an evaporator.
[0076] The low temperature low pressure liquid refrigerant sent to
the indoor heat exchanging device 1a removes heat from the indoor
air and is evaporated. In this process, this refrigerant chills the
indoor air and becomes low temperature low pressure gas
refrigerant, and is introduced to the 4-way valve 18 through the
operating valve 21 and the refrigerant pipe 2.
[0077] The low temperature low pressure gas refrigerant introduced
to the 4-way valve 18 flows into the accumulator 14 from the port E
via the port S. After the liquid content is separated here, the gas
refrigerant is absorbed in the compression device 11. The gas
refrigerant absorbed by the compression device 11 is compressed by
the operation of the compression device, and becomes high
temperature high pressure gas refrigerant to be sent to the outdoor
heat exchanging device 12; thus, the refrigerating cycle where the
refrigerant repeatedly changes state can be formed.
[0078] Additionally, in air cooling operations, the supply of
engine coolant water to the bypass channel 80 is stopped.
[0079] Second Embodiment
[0080] In the above-mentioned snowy areas, because outdoor air
temperature is generally low, the lack of air heating capacity is
of concern. Under such conditions, it is anticipated that the
amount of heat which can be used to prevent snow from accumulating
and to melt the snow is in short supply.
[0081] In the GHP of the second embodiment of present invention, as
shown in FIG. 4, an exhaust gas heating device 55 which heats
exhaust gas which is exhausted from the gas engine GE and increases
the amount of thermal energy collectable in an exhaust gas heat
exchanging device 34 is provided in the fuel gas system 50 which
connects the gas engine GE and the exhaust gas heat exchanging
device 34.
[0082] The exhaust gas system 50 is a system for releasing the
exhaust gas of the gas engine GE to the atmosphere, the exhaust gas
system 50 is provided with the muffler 51 and the top of exhaust
flue 52. The exhaust gas which is exhausted from the gas engine GE
flows through above exhaust gas heat exchanging device 34, heats
the engine coolant water, and then, after that, the exhaust gas is
released from the top of exhaust flue 52 into the atmosphere.
[0083] The amount of thermal energy retained in the exhaust gas
heating device 55 increases by further heating high temperature
exhaust gas exhausted from the gas engine GE with other sources of
heat, or by adding (mixing) high temperature combustion gas
retaining large amounts of thermal energy.
[0084] The embodiment of the above exhaust gas heating device is
explained with reference to the drawings as follows. The drawings
which are used in the explanation are show the features in FIG. 4
by enlarging an important part.
[0085] In the first embodiment shown in FIG. 5, the combusting
device for heating exhaust gas 70 which heats the exhaust gas
exhausted from the gas engine GE and increases the amount of
thermal energy which is collectible in the exhaust gas heat
exchanging device 34 is provided.
[0086] This combustion device for heating exhaust gas 70 comprises
a hollow combustor 71, a combustion nozzle 72 provided in the
combustor 71, a fuel supplying system 73 which supplies fuel and
air to the combustion nozzle by a predetermined mixture ratio, a
combustion gas supplying channel 94 which supplies combustion gas
generated by combusting the fuel with the combustion nozzle 72,
from the combustor 71 to exhaust gas exhausted from the gas engine
GE.
[0087] That is, in the combustion device for heating exhaust gas
70, combustion gas generated by combusting fuel in the combustor 71
is mixed with the exhaust gas exhausted from the gas engine GE of
the gas heat pump type air conditioning device via combustion gas
supplying channel 94 so as to be supplied to the exhaust gas system
50.
[0088] In the embodiment shown in the drawing, although the
combustion gas supplying channel 94 joins to a piping of the
exhaust system 50 between the gas engine GE and the exhaust gas
heat exchanging device 34, the combustion gas may be supplied
directly inside the exhaust gas heat exchanging device 34.
[0089] In the fuel supplying system 73, a control valve 73a is
provided, an air-fuel mixture in which fuel and air are mixed in
appropriate ratio is supplied to the combustion nozzle 72 via this
control valve 73a. The control valve 73a opens when a combusting
device for heating exhaust gas 70 operates, in other words, when an
outdoor air temperature detecting device 45 detects a temperature
lower than a predetermined value during air heating operation and a
control signal output from the control section 75 is received. As
an outdoor air temperature detecting device 45, a temperature
sensor which can be provided in an appropriate place near the
outdoor unit can be mentioned. Also, other types of outdoor air
temperature detecting devices, can be mentioned,. Also, the
condition of outdoor air temperature can be determined depending on
the condition of the refrigerant such as temperature and pressure
detected by various sensors which are provided in the channel for
circulating the refrigerant.
[0090] When a detecting signal indicating low outdoor temperature
is input to the control section 75, the control section 75 opens
the control valve 73a to supply fuel and air to the combustion
nozzle 72, and the air-fuel mixture is ignited in the combustion
nozzle 72.
[0091] When air-fuel mixture is combusted, high temperature
combustion gas is generated to be supplied to the exhaust system
50, and thus the thermal energy retained in the combustion gas is
added to the exhaust gas. Because of this, the amount of heat which
can be absorbed in the engine coolant water in the exhaust gas heat
exchanging device increases, the engine coolant water is more
highly heated and can be supplied to the water heat exchanging
device 13. Accordingly, the amount of heat for heating the
refrigerant in the water heat exchanging device 13 increases, and
it is possible to evaporate low temperature low pressure
refrigerant even during low outdoor air temperature and to supply
the refrigerant to the refrigerating cycle. Also a greater amount
of heat, which can be used to melt snow in the bypass pipe channel
80, is obtained.
[0092] The fuel to be used in the above combusting device for
heating exhaust gas 70 should preferably be gas fuel such as
municipal gas which is used similarly in the gas engine GE. This is
because the gas engine GE and the fuel system can be used
compatibly, and additionally the cost of the fuel is low.
[0093] In the second example of the second embodiment as shown in
the FIG. 6, the combustion nozzle 72 of the combusting device for
heating exhaust gas 70A is provided inside the hollow combustoring
device body 71A which can be compatibly the exhaust gas heat
exchanging device 34A and the casing. Other factors are similar to
the first embodiment as shown in FIG. 5, and the same reference
numerals are used and detailed explanation is omitted.
[0094] In this combusting device for heating exhaust gas 70A which
is constructed in such a way, the amount of heat of the combustion
gas generated inside the combusting device body 71A is directly
added to the exhaust gas passing through the exhaust gas heat
exchanging device 34A by combusting the air-fuel mixture in the
combustion nozzle 72. By doing this, the engine coolant water
flowing through the group of pipes 34a can be heated highly
efficiently with no thermal loss, and also, it can be expected that
exhaust gas and engine coolant water are heated by radiating heat
of a flame.
[0095] Consequently, in the third example of the second embodiment
shown in FIG. 7, the combustion nozzle 72 of the combusting device
for heating exhaust gas 70B is provided in hollow combusting device
body 71B which is compatible with the catalyst container which
contains the exhaust gas cleaning catalyst 76. Other factors are
similar to the first embodiment as shown in FIG. 5, and the same
reference numerals are used and detailed explanation is
omitted.
[0096] The combusting device for heating exhaust gas 70B containing
the exhaust gas cleaning catalyst 76 is provided in the exhaust
system 50 to be located between the gas engine and the exhaust gas
heat exchanging device 34. As an exhaust gas cleaning catalyst 76,
for example, a rhodium catalytic converter is preferably mentioned.
By constructing it in this way, it is possible to increase the heat
for heating the engine coolant water at the same time as cleaning
the exhaust gas of the gas engine GE and the exhaust gas.
[0097] Also, it is known that the cleaning of exhaust gas by the
exhaust gas cleaning catalyst 76 can be done more efficiently when
the exhaust gas is at a high temperature; therefore, raising the
temperature of the exhaust gas by adding combustion gas can also
lead to the promotion of cleaning the combustion gas by the
catalyst.
[0098] As explained above, the exhaust gas heating device 55 which
can heat the exhaust gas according to necessity during air heating
operation is provided, thus more heat is added to waste heat of the
engine, and therefore it is possible to supply more thermal energy
to exhaust gas heat exchanging device 34 and the engine coolant
water can be heated to higher temperature than conventional
energy.
[0099] Because of this, even in the cold areas where outdoor air
temperature may become quite low and it snows, the refrigerant can
be evaporated in the water heat exchanging device 13 by exchanging
heat with high temperature engine coolant water retaining large
amounts of thermal energy. Also, it is possible to melt snow by
using the engine coolant water after the refrigerant is heated by
the water heat exchanging device 13. Accordingly, the refrigerating
cycle can be maintained by using heat supplied from the waste heat
of the engine and the exhaust gas heating device 55 even during low
outdoor air temperatures in which sufficient amounts of heat
necessary to evaporate the refrigerant in outdoor heat exchanging
device 12 cannot be obtained from outdoor air; thus, sufficient air
heating operating capacity is obtained, and air heating capacity
can be enhanced even during low outdoor air temperature. Also the
amount of thermal energy of engine coolant water which can be used
to melt snow can be increased.
[0100] Third Embodiment
[0101] This embodiment is in consideration of usage in snowy areas
where the lack of thermal energy which can be used for air heating
operation and melting snow due to the low outdoor air temperature
is of concern similarly to the above second embodiment.
[0102] In the GHP of this embodiment, the heating device 40 is
provided so as to heat engine coolant water in appropriate points
of the engine coolant water system. This heating device 40 is
provided in the bypass channel 36 formed by dividing the engine
coolant water system after the gas engine GE is cooled. In the
branching part of the bypass channel 36, the flow control valve 37
is provided as a channel change switching device. In an example
shown in the drawing, the bypass channel 36 joins the upstream of
the flow control valve 35A after separated in the downstream of the
gas engine GE. The divergence of this flow control valve 37 can be
adjusted, and the entire amount can flow to either of channel, or
dividing the flow by a certain ratio is also possible according to
necessity.
[0103] The channel change switching device is not limited to the
above flow control valve 37, the three way valve of which
divergence (amount of flow) cannot be adjusted can be used, and the
combined use of two separate switch valves is also possible.
[0104] FIG. 9 shows an enlarged peripheral part of above heating
device 40. Here, the heating device 40 which is provided in the
engine coolant water system of GHP and is an engine coolant water
heating device in order to heat the engine coolant water flown
after cooling the gas engine GE, comprises a frame body 42 which is
provided with a ventilation fan 41, a group of pipes 36a which is
provided in the frame body 42 to flow the engine coolant water, a
combustor 43 provided in the frame body 42, a fuel supplying system
44 which supplies fuel and air to the combustor 43 at a
predetermined ratio, and the engine coolant water flowing through
the group of pipes 36a is heated by the combustor 43.
[0105] The ventilation fan 41 is provided to ventilatethe inside
the frame body 42 which contains the group of pipes 36a and the
combustor 43. The combustor 43 receives the supplied air-fuel
mixture of which the mixture ratio is appropriately predetermined
from the fuel supplying system 44, combusts the air-fuel mixture,
and generates high temperature combustion gas. This combustion gas
is exhausted to the outside of the frame body 42 by the ventilation
fan 41 after heating the engine coolant water flowing through the
group of pipes 36a. Additionally, the combustor 43 is provided in
the frame body 42, thus heating by radiation heat generated by the
combustion of the air-fuel mixture can be expected.
[0106] As explained above, the heating device 40 can heat the
engine coolant water according to necessity when air heating
operation is performed, the engine coolant water retaining greater
amounts of thermal energy to which greater amounts of heat is added
together with waste heat of the engine can be supplied to the water
heat exchanging device 13.
[0107] By this, even in cold areas where outdoor air temperature is
quite low and it snows, by the exchange of heat with high
temperature engine coolant water retaining large amounts of thermal
energy, the refrigerant can be evaporated in the water heat
exchanging device 13, and furthermore, it is possible to melt snow
by using the engine coolant water after the refrigerant is heated
in the water heat exchanging device 13. Accordingly, even during
low outdoor air temperature where sufficient amounts of heat for
evaporating the refrigerant in the outdoor heat exchanging device
12 cannot be obtained from outdoor air, it is possible to maintain
the refrigerating cycle by using the heat supplied from the waste
heat of the engine and the heating device 40; therefore, it is
possible to obtain sufficient air heating capacity to enhance the
air heating operation capacity during low outdoor air temperature.
Also, it is possible to increase the amount of heat of the engine
coolant water which can be used to melt snow.
[0108] Additionally, the construction of present invention is not
limited to the above embodiments, for example, factors such as the
number and the variation of the devices used for the refrigerating
cycle can be preferably changed within the scope of features of the
present invention.
* * * * *