JPH11294894A - Outdoor unit and air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress reduction of performance of an exhaust gas heat exchanger and deterioration of lubricating oil in a gasoline engine by providing a first flow control valve for changing the flow rate of cooling water flowing into either a water-heat exchanger or a radiator. SOLUTION: When starting and the like of an engine, the travel of a 3-way flow control valve 57 is adjusted to set the flow of a radiator 53 to 0, and the travel of a 3-way flow control valve (a first flow control valve) 56 is adjusted to set the flow to a water-heat exchanger 32 to 0, thereby to allow cooling water to circulate through a bypass piping 55. Thus, only the heat recovery from exhaust gas is performed in an exhaust gas heat exchanger 54, so that the cooling water is heated quickly. Since the time the exhaust gas is excessively cooled is reduced, condensation of the exhaust gas becomes difficult. As a result, it becomes difficult for moisture of strong acidity to stay inside the exhaust gas heat exchanger 54 or a gasoline engine 41, so that reduction of performance of the exhaust gas heat exchanger 54 and deterioration of the lubricating oil in the gasoline engine 41 can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas heat pump type air conditioner in which a compressor is driven by a gas engine and exhaust gas of the gas engine is used as a heating source of a liquid refrigerant during a heating operation. .

[0002]

2. Description of the Related Art An air conditioner that performs cooling and heating using a heat pump includes a refrigerant circuit including elements such as an indoor heat exchanger, a compressor, an outdoor heat exchanger, and an expansion valve. Cooling and heating of the room is realized by exchanging heat in the indoor heat exchanger and the outdoor heat exchanger while the refrigerant passes through this circuit. Further, the refrigerant circuit may be provided with a refrigerant heater for directly heating the refrigerant itself, instead of relying solely on receiving the heat of the refrigerant by the outdoor heat exchanger (during the heating operation). .

In recent years, as a power source for a compressor in the above-described refrigerant circuit, a type using a gas engine instead of a commonly used electric motor has been developed. An air conditioner using this gas engine is generally called a gas heat pump type air conditioner (hereinafter abbreviated as GHP). According to this GHP, a relatively inexpensive gas can be used as fuel, so that the running cost does not increase as in an air conditioner (hereinafter abbreviated as EHP) equipped with a compressor using an electric motor. Costs can be reduced.

Further, in the GHP, for example, during heating operation, if the heat of the high-temperature exhaust gas discharged from the gas engine is used as a heating source for the refrigerant, it is possible to obtain an excellent heating effect, Use efficiency can be improved. By the way, the heating capacity at the time of low outside air temperature is about 1.2 to 1.5 times higher than the EHP. Also,
By introducing such a mechanism, in the refrigerant circuit,
It is not necessary to specially install equipment such as the above-described refrigerant heater.

[0005] In addition, in the GHP, the so-called defrosting operation of the outdoor heat exchanger required for the heating operation is also performed.
It can be carried out using the exhaust heat of the engine. Generally, in the defrost operation in the EHP, the heating operation is stopped and the cooling operation is temporarily performed to remove the frost from the outdoor heat exchanger. In this case, since the cool air is blown into the room, the comfort of the room environment is impaired. In the GHP, the continuous heating operation becomes possible due to the above-described circumstances, and there is no occurrence of a problem that is a concern in the EHP.

[0006]

Although the GHP has many advantages as described above, the following problems have been pointed out with respect to the conventional GHP.

The gas used as the fuel for the gas engine includes L.
NG (liquefied natural gas) and LPG (liquefied petroleum gas)
Etc. are used. These gases contain a large amount of moisture, and most of the gas that is burned is discharged together with the exhaust gas. This moisture contains NO _x (nitrogen oxide).
Is contained in a large amount and is strongly acidic. Therefore, the exhaust gas system for guiding the exhaust gas discharged from the gas engine to the outside is provided with a countermeasure for collecting and neutralizing the water condensed at the top of the exhaust gas by a drain filter.

However, in the GHP, the exhaust gas heat exchanger recovers the heat of the exhaust gas to the cooling water of the gas engine, and the heat is taken away by the cooling water to cool the exhaust gas. Moisture may be condensed before reaching the temperature. Such Therefore, it remains inside the strongly acidic water exhaust gas heat exchangers and gas engine containing a large amount of NO _x, or early lubricant degradation in a gas engine or degrade the performance of the exhaust gas heat exchanger There was a problem.

The present invention has been made in view of the above circumstances, and an object of the present invention is to make it difficult for water containing NO _x in exhaust gas to condense in an exhaust gas heat exchanger, thereby reducing exhaust gas. The purpose is to suppress the deterioration of the performance of the heat exchanger and the deterioration of the lubricating oil in the gas engine.

[0010]

The present invention has the following arrangement as means for solving the above-mentioned problems. That is, the outdoor unit according to claim 1 performs an heat exchange between the outdoor heat exchanger that performs heat exchange between the outdoor air and the refrigerant, and heat exchange between the outdoor heat exchanger or the indoor air and the refrigerant. A compressor for sending a high-temperature and high-pressure gas refrigerant to the indoor heat exchanger;
A gas engine that drives the compressor, an exhaust gas heat exchanger that collects heat of exhaust gas discharged from the gas engine into cooling water of the gas engine, and a heat gas that is recovered by the cooling water in the exhaust gas heat exchanger. An outdoor unit comprising: a water heat exchanger for recovering heat to a refrigerant; and a radiator for releasing heat recovered to the cooling water in the exhaust gas heat exchanger to the outside air, wherein the water heat exchanger or the radiator is provided. A bypass pipe that bypasses at least one of the above, a gas temperature detecting unit that detects a temperature of the exhaust gas discharged from the exhaust gas heat exchanger, and a temperature of the exhaust gas detected by the gas temperature detecting unit. The flow rate of the cooling water flowing into the bypass pipe and the flow rate of the cooling water flowing into any of the bypassed water heat exchanger and the radiator are distributed. It is characterized by comprising a first flow control valve to vary.

In the outdoor unit according to the first aspect of the present invention, when the cooling water is in a cold state, such as when the engine is started, the heat of the exhaust gas is recovered by the cooling water, and the temperature of the exhaust gas is reduced to produce the exhaust gas. When the contained water condenses, the first
By adjusting the opening of the flow control valve to allow the cooling water to flow through the bypass pipe and to bypass at least one of the water heat exchanger and the radiator, the refrigerant can recover heat or release it to the outside The cooling water is circulated and only the heat recovery from the exhaust gas in the exhaust gas heat exchanger is performed, and the cooling water is rapidly heated. When the heating time is shortened by rapidly heating the cooling water, the time during which the exhaust gas is excessively cooled in the exhaust gas heat exchanger is also shortened, so that condensation hardly occurs.

According to a second aspect of the present invention, there is provided an air conditioner for exchanging heat between outdoor air and a refrigerant, and exchanging heat between the outdoor heat exchanger or indoor air and a refrigerant. A compressor for delivering a high-temperature and high-pressure gas refrigerant to an indoor heat exchanger to be performed;
A gas engine that drives the compressor, an exhaust gas heat exchanger that collects heat of exhaust gas discharged from the gas engine into cooling water of the gas engine, and a heat gas that is recovered by the cooling water in the exhaust gas heat exchanger. An outdoor unit including a water heat exchanger for recovering heat to a refrigerant, and a radiator for releasing heat recovered in the cooling water in the exhaust gas heat exchanger to the outside air; the indoor heat exchanger; and indoor air. An air conditioner comprising: an indoor unit including a fan for circulating air; a bypass pipe that bypasses at least one of the water heat exchanger and the radiator; and an exhaust gas exhausted from the exhaust gas heat exchanger. A gas temperature detecting means for detecting a temperature of the exhaust gas, and a cooling means which is controlled based on the temperature of the exhaust gas detected by the gas temperature detecting means, and which is controlled to flow into the bypass pipe. Water flow and bypassed the water heat exchanger, it is characterized by comprising a first flow control valve for dispensing varying the flow rate of the cooling water flowing into one of the radiator.

[0013] In the air conditioner according to the second aspect, when the temperature of the exhaust gas decreases and moisture contained in the exhaust gas condenses, such as when the engine is started, the opening of the first flow control valve is increased. By adjusting the cooling water to flow through the bypass pipe and bypassing at least one of the water heat exchanger and the radiator, the cooling water is circulated without recovering heat to the refrigerant or discharging it to the outside, and exhaust Only the heat recovery from the exhaust gas in the gas heat exchanger is performed, and the cooling water is rapidly heated. When the heating time is shortened by rapidly heating the cooling water, the time during which the exhaust gas is excessively cooled in the exhaust gas heat exchanger is also shortened, so that condensation hardly occurs.

According to a third aspect of the present invention, there is provided an outdoor unit for exchanging heat between outdoor air and refrigerant, and exchanging heat between the outdoor heat exchanger or indoor air and refrigerant. A compressor that sends a high-temperature and high-pressure gas refrigerant to an indoor heat exchanger, a gas engine that drives the compressor, and an exhaust gas that collects heat of the exhaust gas discharged from the gas engine into cooling water of the gas engine A heat exchanger, a water heat exchanger for recovering heat recovered in the cooling water in the exhaust gas heat exchanger to a refrigerant, and a radiator for releasing the heat recovered in the cooling water in the exhaust gas heat exchanger to the outside air An outdoor unit comprising: a gas temperature detecting means for detecting a temperature of the exhaust gas discharged from the exhaust gas heat exchanger; anda control unit based on the temperature of the exhaust gas detected by the gas temperature detecting means. The said water It is characterized in that it comprises a second flow control valve for the flow rate of the cooling water flowing into the flow rate of the coolant flowing into the exchanger radiator distributed manner changed.

In the outdoor unit according to the third aspect, since the gas engine is constantly driven and the cooling water is warmed, a high heating capacity is required and the amount of heat recovery in the water heat exchanger increases. When the temperature of the cooling water decreases due to the increase of the heat radiation amount in the radiator due to the change of the outside air temperature, and the water contained in the exhaust gas condenses due to this, the second flow control valve Adjusting the opening to change the ratio between the flow rate to the radiator and the flow rate to the water heat exchanger, increase the flow rate to either one of the relatively small amount of heat recovered from the cooling water, and recover from the cooling water The cooling water is circulated after reducing the flow rate to the other which generates relatively more heat. As a result, the amount of heat recovered from the cooling water decreases, the temperature of the cooling water flowing into the exhaust gas heat exchanger increases, and the supercooling of the exhaust gas is suppressed, and the condensation of the exhaust gas is prevented.

According to a fourth aspect of the present invention, there is provided an air conditioner for exchanging heat between outdoor air and a refrigerant, and exchanging heat between the outdoor heat exchanger or indoor air and a refrigerant. A compressor that sends a high-temperature and high-pressure gas refrigerant to an indoor exchanger to be performed, a gas engine that drives the compressor, and exhaust gas heat that collects heat of exhaust gas discharged from the gas engine into cooling water of the gas engine Exchanger, a water heat exchanger for recovering the heat recovered in the cooling water in the exhaust gas heat exchanger to the refrigerant,
Similarly, an outdoor unit including a radiator that emits heat collected in the cooling water to the outside air in the exhaust gas heat exchanger, and an indoor unit including the indoor heat exchanger and a fan that circulates indoor air. An air conditioner comprising: gas temperature detecting means for detecting a temperature of exhaust gas discharged from the exhaust gas heat exchanger; andcontrolling based on a temperature of the exhaust gas detected by the gas temperature detecting means, It is characterized by comprising a second flow control valve for distributively changing the flow rate of the cooling water flowing into the water heat exchanger and the flow rate of the cooling water flowing into the radiator.

In the air conditioner according to the present invention, when the temperature of the exhaust gas decreases and the moisture contained in the exhaust gas condenses from a state in which the gas engine is constantly driven and the cooling water is warmed. Adjusting the opening of the second flow control valve to change the ratio between the flow rate to the radiator and the flow rate to the water heat exchanger, so that the heat recovered from the cooling water is relatively small. And the flow of cooling water to the other side, where the heat recovered from the cooling water is relatively large, is reduced, and then the cooling water is circulated. As a result, the amount of heat recovered from the cooling water decreases, the temperature of the cooling water flowing into the exhaust gas heat exchanger increases, and the supercooling of the exhaust gas is suppressed, and the condensation of the exhaust gas is prevented.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The GHP (gas heat pump type air conditioner) 1 shown in FIG. 4 is mainly composed of an indoor unit 10 and an outdoor unit 20. The indoor unit 10 includes an indoor heat exchanger that evaporates and evaporates a low-temperature and low-pressure liquid refrigerant to remove heat from indoor air during a cooling operation, and condenses and liquefies a high-temperature and high-pressure gas refrigerant to heat indoor air during a heating operation. 11 and a fan 12 for circulating indoor air.

The outdoor unit 20 includes a refrigerant circuit section 30 inside which a refrigerant circuit is further formed, and a gas engine 4.
The gas engine unit 40 mainly includes a gas engine unit 40 and has components attached thereto.

In the refrigerant circuit section 30, the outdoor heat exchanger 3
1, water heat exchanger 32, compressor 33, accumulator 3
4, four-way valve 35, oil separator 36, expansion valve 37,
And a fan 39. Outdoor heat exchanger 31
In the cooling operation, the high-temperature and high-pressure gas refrigerant is condensed and liquefied to radiate heat to the outdoor air. On the contrary, in the heating operation, the low-temperature and low-pressure liquid refrigerant evaporates and removes heat from the outdoor air. That is, at the time of each operation of the cooling and heating, the outdoor heat exchanger 3
1 performs the reverse operation of the indoor heat exchanger 11 described above.

The water heat exchanger 32 is provided for recovering heat from a coolant from a cooling water of the gas engine 41 described later. That is, at the time of the heating operation, the refrigerant does not rely only on the heat exchange in the outdoor heat exchanger 31 but also receives heat from the cooling water of the gas engine 41, so that the effect of the heating operation can be further enhanced. It becomes possible.

The compressor 33 compresses the gas refrigerant sucked from either the indoor heat exchanger 11 or the outdoor heat exchanger 31 and discharges it as a high-temperature and high-pressure gas refrigerant. Thereby, at the time of cooling, even if the outside air temperature is high, the refrigerant can radiate heat to the outdoor air through the outdoor heat exchanger 31,
At the time of heating, heat can be given to indoor air through the indoor heat exchanger 11.

The accumulator 34 is provided for storing a liquid component contained in the gas refrigerant flowing into the compressor 33. Further, the four-way valve 35 is provided for selectively sending out the high-temperature and high-pressure gas refrigerant compressed in the compressor 33 to either the indoor heat exchanger 11 or the outdoor heat exchanger 31. The oil separator 36 separates oil contained in the refrigerant.

The expansion valve 37 depressurizes and expands the high-temperature and high-pressure liquid refrigerant sent from the outdoor heat exchanger 31 during the cooling operation to make it a low-temperature and low-pressure liquid refrigerant. The fan 39 is provided to introduce outdoor air into the outdoor unit 20 and to circulate the air to the outdoor heat exchanger 31 and a radiator 53 described later.

On the other hand, in the gas engine section 40, a cooling water system 50, an exhaust gas system 60,
Four systems, a fuel intake system 70 and an engine oil system 80, are provided. The gas engine 41 includes the refrigerant system 30
It is connected to a compressor 33 installed therein by a shaft or a belt or the like, and power is transmitted from the gas engine 41 to the compressor 33.

The cooling water system 50 is provided with a water pump 51, a reservoir tank 52, and a radiator 53, and is a system for cooling the gas engine 41 with cooling water passing through a circuit constituted by these components. The water pump 51 is a gas engine 4
It is provided to circulate one cooling water through the circuit.
The reservoir tank 52 is used to temporarily store an excess of the cooling water flowing through the circuit, or to supply the cooling water when the circuit runs short of the cooling water. The radiator 53 is integrally formed with the outdoor heat exchanger 31 and is provided to release heat taken from the gas engine 41 by the cooling water to the outside air.

The cooling water system 50 is provided with an exhaust gas heat exchanger 54 in addition to the above configuration. This is provided to recover the heat of the exhaust gas into the cooling water. The cooling water system 50 includes the water heat exchanger 3 described above.
2 are provided, and are arranged so as to straddle both the refrigerant system 30 and the cooling water system 50. For these reasons, during the heating operation, the cooling water not only removes heat from the gas engine 41 but also recovers heat from the exhaust gas, and the recovered heat is transferred from the cooling water to the refrigerant through the water heat exchanger 32. The mechanism is given.

The exhaust gas system 60 includes a muffler 61, an exhaust top 62, and a drain filter 63.
This is a system for guiding exhaust gas discharged from the outside to the outside.
The muffler 61 is provided to absorb noise caused when the gas engine 41 discharges exhaust gas. The exhaust top 62 separates moisture contained in the exhaust gas,
This is provided so as not to be scattered to the external environment. From the viewpoint of this function, the exhaust top 62 is sometimes called an exhaust separator. The drain filter 63 is provided for temporarily storing the water separated from the exhaust top 62 just described. Further, a neutralizing agent is provided inside the drain filter 63. This corresponds to the fact that the moisture contained in the exhaust gas is generally strongly acidic, and is provided for the purpose of neutralizing this acidic moisture to render it harmless.

The fuel intake system 70 includes a gas regulator 7
1, solenoid valve 72, intake box 73, air cleaner 74
And a system for supplying fuel and air to the gas engine 41. The gas regulator 71 includes an electromagnetic valve 72
It is provided for adjusting the delivery pressure of the gas supplied from the outside of the outdoor unit 20 via the. On the other hand, the intake box 73 is provided to take in air from outside the outdoor unit 20. In addition, the intake box 73
Also has the function of suppressing the generation of noise during intake. The air cleaner 74 is provided for removing dust from the air thus sucked. As described above, the gas and air supplied from the outside are respectively shown in FIG.
As shown in the figure, the gas regulator 71 and the air cleaner 7
After passing through No. 4, they are mixed and sent to the gas engine 41 to be used as fuel.

The engine oil system 80 has an oil sub-tank 81 and is provided for supplying lubricating oil to the gas engine 41. An oil pan 41 a is provided below the gas engine 41 to receive the oil in the oil sub tank 81.

The outdoor unit 20 of the configuration described above
5 and 6 are housed in the outdoor unit housing 21 as shown in FIGS. As shown in these figures, the interior of the outdoor unit housing 21 is
The upper and lower parts are divided into two by two. These upper and lower spaces are now called the heat exchange room 23 and the machine room 24, respectively.
I will call it. 5 and 6, the illustration of the piping described with reference to FIG. 4 is omitted.

The heat exchange chamber 23 is provided with an outdoor heat exchanger 31 and a radiator 53 so as to cover all the front and back surfaces of the outdoor unit housing 21. The outdoor heat exchanger 31 and the radiator 53 have an integrated structure as described above. In addition, the muffler 61, the exhaust top 62, and the intake box 7 of the elements shown in FIG.
3 and the like are provided. Incidentally, the muffler 61 and the exhaust top 62 shown in FIG. 5 and the piping 60a connecting them are not shown in FIG.

In the heat exchange chamber 23, in addition to the components described above, a fan 91, a fan motor 92, a fan fixture 9
3 are provided. The fan 91 is attached to an output shaft of a fan motor 92 attached to a fan attachment 93 suspended from a ceiling surface of the outdoor unit housing 21. In the present embodiment, two sets of the fans 91 are mounted. Openings 94 are formed in the ceiling surface of the outdoor unit housing 21 so as to correspond to the mounting positions of the fans 91.
The opening 94 is provided with a mesh cover 95. The fan 91 assists the operation of the outdoor heat exchanger 31.

In the heat exchange chamber 23, two ventilation boxes 96 are provided on the partition plate 22, and a ventilation fan 97 is provided inside each of them. The ventilation box 96 and the ventilation fan 97 are provided to guide heat inside the machine room 24 to the heat exchange room 23. Therefore, the air heated in the machine room 24 is supplied to the ventilation fan 9.
6. The air is discharged to the outside of the outdoor unit housing 21 through the path of the heat exchange chamber 23 and the fan 91. Note that the intake box 73 is placed above the ventilation boxes 96. The air taken from the intake box 73 is
Gas engine 4 through the space between both ventilation boxes 96
1 to reach.

Next, the machine room 24 will be described.
Most of the components described in FIG. 4 and the components of each system are housed in the machine room 24. 5 and 6, the compressor 33, the accumulator 34, the four-way valve 35, and the oil separator 36 in the refrigerant circuit unit 30, and the gas engine 41, the drain filter 63, and the air cleaner 74 in the gas engine unit 40 are shown in FIGS. Are shown respectively.

In the machine room 24, a drain pipe 101 is provided in addition to the above components. The drain pipe 101 is a pipe that connects the opening 22 a provided in the partition plate 22 and the floor opening 25 of the outdoor unit housing 21.
This is achieved by the outdoor unit housing 2 through the ceiling opening 94 described above.
1 is provided to discharge rainwater that has entered inside to the exterior of the outdoor unit housing 21.

In the machine room 24, a base plate 102,
An anti-vibration rubber 103 is provided. The base plate 102 is a substantially square plate, and is used as a floor on which the components in the refrigerant circuit unit 30 and the gas engine unit 40 housed in the machine room 24 are mounted. This base plate 10
At the four corners of the lower surface 2, anti-vibration rubber 103 is arranged. Therefore, the base plate 102 and the vibration isolating rubber 103 are connected to the refrigerant circuit unit 30 and the gas engine
It has the function of suppressing the mechanical vibration generated from.

In the cooling water system 50 disposed in the machine room 24, a bypass pipe is connected to the water heat exchanger 32 so as to connect the front and rear thereof to bypass the cooling water flowing into the water heat exchanger 32, as shown in FIG. 55 are provided. In addition, a passage through which the cooling water flows through the water heat exchanger 32 and the bypass piping 5
In the branch with 5, a three-way flow control valve (first flow control valve)
56 are provided. The three-way flow control valve 56 is provided to control the flow rate of the cooling water flowing into the water heat exchanger 32 and the flow rate of the cooling water flowing into the bypass pipe 55 in a distributed manner. Further, the three-way flow control valve 56 is provided with a servomotor 56a for adjusting the opening degree of the valve.

The water heat exchanger 32 and the radiator 53 are arranged in parallel in a pipe 50a for circulating cooling water.
Further, a three-way flow control valve (second flow control valve) 57 is provided at a branch of a path for flowing the cooling water through the water heat exchanger 32 and a path for flowing the cooling water through the radiator 53. The three-way flow control valve 57 is provided to control the flow rate of the cooling water flowing into the water heat exchanger 32 and the flow rate of the cooling water flowing into the radiator 53 in a distributed manner. The three-way flow control valve 57 is also provided with a servomotor 57a for adjusting the opening of the valve. Three-way flow control valve 57, 5
The exhaust gas heat exchanger 5 is controlled by control means (not shown) based on a detection result of a temperature sensor & described later.
The flow rate of the cooling water flowing through the water heat exchanger 32, the radiator 53, and the bypass pipe 55 so as to maintain the temperature of the gas discharged from the pipe 4 above a predetermined temperature (a temperature at which the exhaust gas is not considered to be condensed). To change.

An exhaust gas system 60 arranged in the machine room 24
, A temperature sensor (gas temperature detecting means) 64 for detecting the temperature of the discharged gas is provided on the gas discharge side of the exhaust gas heat exchanger 54.

The operation of the GHP 1 having the above-described configuration during the operation of each of the indoor cooling and the heating will be described. First, during the cooling operation, the four-way valve 35 of the refrigerant circuit unit 30 is connected to the compressor 33 and the outdoor heat exchanger 3.
1. The indoor heat exchanger 11 and the accumulator 34 are connected to each other. In this state, the high-temperature and high-pressure gas refrigerant discharged from the compressor 33 is sent to the outdoor heat exchanger 31.

The high-temperature and high-pressure gas refrigerant is condensed and liquefied in the outdoor heat exchanger 31, and radiates heat to outdoor air to become a high-temperature and high-pressure liquid refrigerant. Further, the high-temperature and high-pressure liquid refrigerant is reduced in pressure in the process of passing through the expansion valve 37, becomes a low-temperature and low-pressure liquid refrigerant, and is sent to the indoor unit 10.

The low-temperature and low-pressure liquid refrigerant sent to the indoor unit 10 is evaporated and vaporized in the indoor heat exchanger 11, cools by removing heat from the indoor air, and becomes a low-temperature and low-pressure gas refrigerant. It is sent to the refrigerant circuit unit 30 inside.

The low-temperature and low-pressure gas refrigerant sent to the refrigerant circuit unit 30 flows into the accumulator 34 via the four-way valve 35,
After the liquid component is separated, it is sucked into the compressor 33. The gas refrigerant sucked into the compressor 33 is compressed by the operation of the compressor 33, becomes a high-temperature and high-pressure gas refrigerant, and is sent to the outdoor heat exchanger 31 again.

On the other hand, during the heating operation, the four-way valve 35
Is in a state where the compressor 33 and the indoor heat exchanger 11 are connected, and the outdoor heat exchanger 31 and the accumulator 34 are connected. In this state, the high-temperature and high-pressure gas refrigerant discharged from the compressor 33 is supplied to the indoor heat exchanger 1 of the indoor unit 10.
Sent to 1.

The high-temperature and high-pressure gas refrigerant is condensed and liquefied in the indoor heat exchanger 11, radiates heat to indoor air and is heated, and then is converted to a high-temperature and high-pressure liquid refrigerant and sent to the refrigerant circuit unit 30 in the outdoor unit 20. Can be The high-temperature and high-pressure liquid refrigerant sent to the refrigerant circuit unit 30 flows into the outdoor heat exchanger 31. In the outdoor heat exchanger 31, the high-temperature and high-pressure liquid refrigerant takes heat from the outside air and evaporates to become a low-temperature and low-pressure gas refrigerant.

The low-temperature and low-pressure gas refrigerant is supplied to the water heat exchanger 32.
And heat is exchanged with the engine cooling water to be further heated to become a high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant flows into the accumulator 34, where the liquid component is separated, and then sucked into the compressor 33. The gas refrigerant sucked into the compressor 33 is compressed, becomes a high-temperature and high-pressure gas refrigerant, and is sent to the indoor heat exchanger 11 again.

The gas engine 41 is in a driving state for transmitting power to the compressor 33 irrespective of the cooling operation or the heating operation. In the cooling water system 50, the exhaust gas heat exchanger 54 is used.
, Exhaust gas recovery and gas engine cooling are always performed. Then, the cooling water heated after passing through the gas engine after recovering the exhaust heat is circulated to the radiator 53 and the water heat exchanger 32 through a pipe 50 a constituting the cooling water system 50.

By the way, for example, when the engine is started, the cooling water is cooled and the heat of the exhaust gas is recovered by the cooling water, and the temperature of the exhaust gas detected by the temperature sensor 64 becomes lower than a predetermined value. In such a case, it is expected that the exhaust gas is excessively cooled by the cooling water and condensation of moisture contained in the exhaust gas occurs.

Therefore, when the engine is started (when exhaust gas is not discharged and the temperature detected by the temperature sensor 64 is lower than a predetermined value), the opening of the three-way flow control valve 57 is adjusted. The flow rate W3 of the radiator 53 is set to 0, the opening degree of the three-way flow control valve 56 is adjusted to set the flow rate W4 to the water heat exchanger 32 to 0, and the cooling water is supplied to the bypass pipe 55.
To circulate through. When the cooling water flows only through the bypass pipe 55, the cooling water
3 and no heat is recovered by the refrigerant in the water heat exchanger 32, and the exhaust gas heat exchanger 54
In the above, only the heat recovery from the exhaust gas is performed, and the cooling water is rapidly heated. If the cooling water is rapidly heated and the heating time is shortened, the time during which the exhaust gas is excessively cooled in the exhaust gas heat exchanger 54 is shortened, so that the exhaust gas hardly condenses. When the temperature of the exhaust gas reaches a predetermined value, the opening of the three-way flow control valve 56 is adjusted to set the flow rate W5 to the bypass pipe 55 to 0, and the opening of the three-way flow control valve 57 is appropriately adjusted. The supply of the cooling water to both the water heat exchanger 32 and the radiator 53 is started to operate the GHP 1 in earnest.

Further, even when the gas engine 41 is constantly driven and the cooling water is warmed, a high heating capacity is required, so that the amount of heat recovery in the water heat exchanger 32 increases, When the temperature of the cooling water decreases due to an increase in the amount of heat radiation in the radiator 53 due to a change in the air temperature, and the temperature of the exhaust gas detected by the temperature sensor 64 becomes lower than a predetermined value due to this, Three-way flow control valve 57
Is adjusted to change the ratio of the flow rate W3 to the radiator 53 and the flow rate W4 to the water heat exchanger 32, thereby increasing the flow rate to either one of which relatively little heat is recovered from the cooling water. To circulate the cooling water. When the amount of heat recovered from the cooling water decreases, the temperature of the cooling water flowing into the exhaust gas heat exchanger 54 increases, and the supercooling of the exhaust gas is suppressed, so that the condensation of the exhaust gas is suppressed.

Here, the calorific value calculation formula in the exhaust gas heat exchanger 54 is shown. Q for heat exchange and A for heat transfer area
o, the heat exchange rate is K, the exhaust gas inlet temperature is Tgi, the exhaust gas outlet temperature is Tgo, the cooling water inlet temperature is Twi, and the cooling water outlet temperature is Two.

The heat exchange rate K is obtained by calculating the heat transfer coefficient on the exhaust gas side by α
g, the thickness of the pipe wall separating the cooling water and the exhaust gas of the heat transfer tube through which the cooling water flows is l, the heat transfer coefficient of the heat transfer tube is λ, and the heat transfer coefficient of the cooling water side is αw, The heat transfer coefficient on the cooling water side is generally much larger than the heat transfer coefficient on the exhaust gas side. Therefore, the gas-side surface temperature T1 of the heat transfer tubes and the cooling-water-side surface temperature T2 of the heat transfer tubes are Is controlled by the temperature Tw.

The reason why the moisture contained in the exhaust gas condenses is as follows.
Since the temperature Tg of the exhaust gas is lower than the dew point, that is, the gas-side surface temperature T1 of the heat transfer tube is lower than the dew point, the temperature Tw of the cooling water is reduced as described above.
If the temperature T1 is controlled to keep the gas side surface temperature T1 of the heat transfer tube higher than the dew point temperature, it is considered that the condensation of water does not occur.

FIG. 2 shows the heat balance of the cooling water in the cooling water system 50. The heat quantity given to the cooling water in the exhaust gas heat exchanger 54 is Q1, the heat quantity given to the cooling water in the gas engine 41 is Q2, the heat quantity released from the cooling water in the radiator 53 is Q3, and the cooling water is Q4 is the amount of heat recovered from the pump (pump 51
In this case, the amount of heat given to the cooling water is so small that it is neglected here), the flow rate of the cooling water circulated to the cooling water system 50 by the pump 51 per unit time is W, and the flow rate of the cooling water flowing through Flow rate of W
3. Assuming that the flow rate of the cooling water flowing through the water heat exchanger 32 per unit time is W4 and the flow rate of the cooling water flowing through the bypass pipe 55 is W5 per unit time, Q1 + Q2 = Q3 + Q4 (3) W = W3 + W4 + W5 ... (4)

Further, the cooling water outlet temperature of the gas engine 41 is Teo, the cooling water outlet temperature of the radiator 53 is Tw ₃ , and the cooling water outlet temperature of the water heat exchanger 32 is Tw _4.
And then, when the specific heat of the cooling water and c, W · c · Teo = Q3 + Q4 + W · c · Twi ... (5) Q3 = W3 · c · (Teo-Tw 3) ... (6) Q4 = W4 · c · (Teo _{-Tw 4) ... (7) (} 5) formula, (6), (7) from the equation, W · Teo = W3 · ( Teo-Tw 3) + W4 · (Teo-Tw 4) + W · Twi ... (8 ) When formula (8) is arranged for the cooling water inlet temperature Twi,

Q1 = W · c · (Two−Twi) (10) Q2 = W · c · (Teo−Two) (11) Equations (6), (7), (10), (11) ) substituting equation in the equation (3), W · (Two-Twi) + W · (Teo-Two) = W3 · (Teo-Tw 3) + W4 · (Teo-Tw 4) ... (12) (12) formula Is arranged for the cooling water inlet temperature Twi, That is, Which is the same as equation (9). Therefore, it can be understood that the control of the cooling water inlet temperature Twi can be performed by changing the ratio between the flow rate W3 of the radiator 53 and the flow rate W4 of the water heat exchanger 32.

Control for maintaining the exhaust gas outlet temperature Tgo in the exhaust gas heat exchanger 54 at a predetermined value or more will be described with reference to a block diagram shown in FIG. The preset exhaust gas outlet temperature target value T and the actual exhaust gas outlet temperature Tgo detected by the temperature sensor 64 are compared in the subtractor S1, and the obtained error signal ε is compared with the PID control device. In step S2, the operation amount of the servomotor 57a is determined in the operation unit S3 from the error signal ε, and the valve opening adjustment unit S4
Then, the opening degree of the three-way flow control valve 57 is adjusted to change the ratio of the flow rate W3 to the radiator 53 and the flow rate W4 to the water heat exchanger 32. By performing the above control, the exhaust gas outlet temperature Tgo is maintained at a predetermined value or higher.

Although the PID control device S2 is used in the above control circuit, a fuzzy control device may be used instead.

According to the GHP configured as described above,
When the temperature of the exhaust gas becomes lower than a predetermined value, such as when the engine is started, the opening of the three-way flow control valve 57 is adjusted to set the flow W3 of the radiator 53 to 0, and the opening of the three-way flow control valve 56 is opened. Is adjusted to make the flow rate W4 to the water heat exchanger 32 zero, and all the cooling water is circulated through the bypass pipe 55, whereby the cooling water is rapidly heated, the heating time is shortened, and the exhaust gas heat exchange is performed. Since the time during which the exhaust gas is excessively cooled in the vessel 54 is reduced, condensation of the exhaust gas is less likely to occur. This makes it difficult for the strongly acidic moisture to stay inside the exhaust gas heat exchanger 54 and the gas engine 41, thereby suppressing the performance degradation of the exhaust gas heat exchanger 54 and the deterioration of the lubricating oil in the gas engine 41. it can.

Further, even if the gas engine 41 is constantly driven and the cooling water is warm, if the temperature of the exhaust gas becomes lower than a predetermined value, the three-way flow control valve 57
Of the flow rate W3 to the radiator 53 and the flow rate W4 to the water heat exchanger 32 by adjusting the opening of the exhaust gas heat exchanger 54, the amount of heat recovered from the cooling water decreases.
Since the temperature of the cooling water flowing into the exhaust gas rises and the supercooling of the exhaust gas is suppressed, the condensation of the exhaust gas hardly occurs. This makes it difficult for the strongly acidic moisture to stay inside the exhaust gas heat exchanger or the gas engine.
4 and deterioration of the lubricating oil in the gas engine 41 can be suppressed.

[0062]

As described above, according to the outdoor unit of the first aspect, when the temperature of the exhaust gas becomes lower than a predetermined value, such as when starting the engine, the first flow control valve is opened. By adjusting the temperature and circulating the cooling water by bypassing the water heat exchanger and radiator, the cooling water is heated quickly and the heating time is shortened, and the exhaust gas in the exhaust gas heat exchanger Since the cooling time is shortened, the exhaust gas hardly condenses. This makes it difficult for the strongly acidic moisture to stay inside the exhaust gas heat exchanger or the gas engine, thereby suppressing the performance of the exhaust gas heat exchanger and the deterioration of the lubricating oil in the gas engine.

According to the air conditioner of the second aspect, when the temperature of the exhaust gas becomes lower than a predetermined value, such as when starting the engine, the opening degree of the first flow control valve is adjusted to perform the water heat exchange. By circulating the cooling water by bypassing the heater and radiator, the cooling water is rapidly heated and the heating time is shortened, and the time during which the exhaust gas is excessively cooled in the exhaust gas heat exchanger is shortened. In addition, the exhaust gas hardly condenses. This makes it difficult for the strongly acidic moisture to stay inside the exhaust gas heat exchanger or the gas engine, thereby reducing the performance of the exhaust gas heat exchanger and the deterioration of the lubricating oil in the gas engine. It is possible to improve the reliability of the machine and realize stable operation.

According to the outdoor unit of the third aspect,
When the temperature of the cooling water decreases and the temperature of the exhaust gas becomes lower than a predetermined value due to this, the opening of the second flow control valve is adjusted to adjust the flow rate to the radiator and the flow rate to the water heat exchanger. By increasing the flow rate to either one of which relatively little heat is recovered from the cooling water and reducing the flow rate to the other, where the heat recovered from the cooling water is relatively high. In addition, the amount of heat recovered from the cooling water decreases, the temperature of the cooling water flowing into the exhaust gas heat exchanger increases, and the supercooling of the exhaust gas is suppressed, so that the exhaust gas hardly condenses. This makes it difficult for the strongly acidic moisture to stay inside the exhaust gas heat exchanger or the gas engine, thereby suppressing the performance of the exhaust gas heat exchanger and the deterioration of the lubricating oil in the gas engine.

According to the air conditioner of the fourth aspect, when the temperature of the cooling water drops and the temperature of the exhaust gas becomes lower than a predetermined value due to this, the opening of the second flow control valve is started. By adjusting the degree, the ratio of the flow rate to the radiator and the flow rate to the water heat exchanger is changed, and the heat recovered from the cooling water is increased to one of the relatively small amounts, and the heat recovered from the cooling water is increased. The amount of heat recovered from the cooling water is reduced by reducing the flow rate to the other, which has a relatively large amount of heat, and the temperature of the cooling water flowing into the exhaust gas heat exchanger is increased, thereby suppressing the supercooling of the exhaust gas. Therefore, the condensation of the exhaust gas hardly occurs. This makes it difficult for the strongly acidic moisture to stay inside the exhaust gas heat exchanger or the gas engine, thereby reducing the performance of the exhaust gas heat exchanger and the deterioration of the lubricating oil in the gas engine. It is possible to improve the reliability of the machine and realize stable operation.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an embodiment of an air conditioner according to the present invention, and is a schematic configuration diagram illustrating a gas engine, a cooling water system, and an exhaust gas system provided in an outdoor unit.

FIG. 2 is an explanatory diagram showing a heat balance of cooling water in a cooling water system.

FIG. 3 is a block diagram showing a control circuit for maintaining an exhaust gas outlet temperature in an exhaust gas heat exchanger at a predetermined value or higher.

FIG. 4 is a schematic configuration diagram illustrating a configuration of an air conditioner.

FIG. 5 is a side sectional view showing a configuration of the outdoor unit.

FIG. 6 is a side sectional view showing the internal configuration of the outdoor unit.

[Explanation of symbols]

 1 GHP 10 Indoor unit 11 Indoor heat exchanger 20 Outdoor unit 31 Outdoor heat exchanger 32 Water heat exchanger 33 Compressor 41 Gas engine 53 Radiator 54 Exhaust gas heat exchanger 55 Bypass pipe 56 Three-way flow control valve (first Flow control valve) 57 Three-way flow control valve (second flow control valve) 64 Temperature sensor (gas temperature detecting means)

Claims (4)

[Claims] 1. An outdoor heat exchanger for exchanging heat between outdoor air and a refrigerant, and an outdoor heat exchanger for exchanging heat between the outdoor heat exchanger and an indoor air and a refrigerant. A compressor that sends out a gas refrigerant, a gas engine that drives the compressor, an exhaust gas heat exchanger that recovers heat of exhaust gas discharged from the gas engine into cooling water of the gas engine,
An outdoor unit comprising: a water heat exchanger that recovers heat recovered in the cooling water in the exhaust gas heat exchanger into a refrigerant; and a radiator that similarly discharges the heat recovered in the cooling water in the exhaust gas heat exchanger to the outside air. A unit, a bypass pipe that bypasses at least one of the water heat exchanger and the radiator, a gas temperature detecting unit that detects a temperature of exhaust gas discharged from the exhaust gas heat exchanger, Controlled based on the temperature of the exhaust gas detected by the temperature detecting means, the flow rate of the cooling water flowing into the bypass pipe and the flow rate of the cooling water flowing into any of the bypassed water heat exchanger and the radiator. And a first flow control valve for distributively changing the flow rate. 2. An outdoor heat exchanger for exchanging heat between outdoor air and a refrigerant, and an outdoor heat exchanger for exchanging heat between the outdoor heat exchanger or the indoor air and the refrigerant. A compressor that sends out a gas refrigerant, a gas engine that drives the compressor, an exhaust gas heat exchanger that recovers heat of exhaust gas discharged from the gas engine into cooling water of the gas engine,
An outdoor unit comprising: a water heat exchanger that recovers heat recovered in the cooling water in the exhaust gas heat exchanger into a refrigerant; and a radiator that similarly discharges the heat recovered in the cooling water in the exhaust gas heat exchanger to the outside air. An air conditioner comprising: a unit; an indoor unit including the indoor heat exchanger; and a fan that circulates indoor air, wherein a bypass that bypasses at least one of the water heat exchanger and the radiator. A pipe, gas temperature detecting means for detecting the temperature of the exhaust gas discharged from the exhaust gas heat exchanger, and a temperature controlled based on the temperature of the exhaust gas detected by the gas temperature detecting means, flowing into the bypass pipe. Flow control valve for distributively changing the flow rate of cooling water to flow and the flow rate of cooling water flowing into one of the bypassed water heat exchanger and the radiator An air conditioner comprising: 3. An outdoor heat exchanger for exchanging heat between outdoor air and a refrigerant, and an outdoor heat exchanger for exchanging heat between the outdoor heat exchanger or the indoor air and the refrigerant. A compressor that sends out a gas refrigerant, a gas engine that drives the compressor, an exhaust gas heat exchanger that recovers heat of exhaust gas discharged from the gas engine into cooling water of the gas engine,
An outdoor unit comprising: a water heat exchanger that recovers heat recovered in the cooling water in the exhaust gas heat exchanger into a refrigerant; and a radiator that similarly discharges the heat recovered in the cooling water in the exhaust gas heat exchanger to the outside air. A gas temperature detecting means for detecting a temperature of the exhaust gas discharged from the exhaust gas heat exchanger, wherein the water temperature is controlled based on the temperature of the exhaust gas detected by the gas temperature detecting means. An outdoor unit, comprising: a second flow control valve for distributively changing a flow rate of the cooling water flowing into the exchanger and a flow rate of the cooling water flowing into the radiator. 4. An outdoor heat exchanger for exchanging heat between outdoor air and a refrigerant, and an outdoor heat exchanger for exchanging heat between the outdoor heat exchanger and the indoor air and the refrigerant. A compressor that sends out a gas refrigerant, a gas engine that drives the compressor, an exhaust gas heat exchanger that recovers heat of exhaust gas discharged from the gas engine into cooling water of the gas engine,
An outdoor unit comprising: a water heat exchanger that recovers heat recovered in the cooling water in the exhaust gas heat exchanger into a refrigerant; and a radiator that similarly discharges the heat recovered in the cooling water in the exhaust gas heat exchanger to the outside air. An air conditioner comprising: a unit; an indoor unit including the indoor heat exchanger; and a fan for circulating indoor air, wherein the temperature of exhaust gas discharged from the exhaust gas heat exchanger is detected. A gas temperature detecting unit, which is controlled based on a temperature of the exhaust gas detected by the gas temperature detecting unit, and distributes a flow rate of the cooling water flowing into the water heat exchanger and a flow rate of the cooling water flowing into the radiator. An air conditioner comprising: a second flow control valve that changes the flow rate.