JPH08100960A - Engine driven heat pump device - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Engine drive heat that can achieve proper heat exchange in the refrigerant circuit by realizing heat exchange between the refrigerant and engine cooling water in proportion to the number of operating indoor heat exchangers. Pump device. A heat exchanger in an engine-driven heat pump device having a refrigerant circuit 22 and an engine cooling water circuit 23, and a double pipe heat exchanger 44 provided between the refrigerant circuit 22 and the cooling water circuit 23. A bypass circuit for bypassing a part of the cooling water flowing to 44 is provided, and the bypass circuit 45 is provided.
A water bypass valve 46 is provided in the air conditioner, and when the refrigerant flow rate is small because the number of indoor heat exchangers 32-1, ... Circuit 4 partially bypassing the double tube heat exchanger 44
5 can be configured to flow to the double tube heat exchanger 44
In the above, the heat quantity corresponding to the heat radiation quantity required for the indoor heat exchangers 32-1, ... In operation is given from the cooling water to the refrigerant, and as a result, the above-mentioned object is achieved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine driven heat pump device having a double tube heat exchanger for recovering engine waste heat.

[0002]

2. Description of the Related Art Generally, an engine-driven heat pump device is provided with an exhaust gas heat exchanger and a double-tube heat exchanger in order to recover engine waste heat and utilize it effectively.

The double-tube exchanger is provided in order to efficiently increase the amount of heat released (heat quantity released from the refrigerant) in the indoor heat exchanger during heating operation. In the heat exchanger, the waste heat recovered from the exhaust gas to the cooling water in the exhaust gas heat exchanger is given to the refrigerant, and as a result, the waste heat recovered from the engine is added to the heat radiation amount of the indoor heat exchanger. Will be done.

[0004]

However, in the so-called multi-operation heat pump device having a plurality of indoor heat exchangers, it is necessary to meet the required performance when operating all indoor heat exchangers during heating operation. Since the heat exchange balance is maintained, for example, when operating only one indoor heat exchanger, the heat exchange in the double-tube heat exchanger exceeds the required performance (heat dissipation amount) of that indoor heat exchanger. There is a problem in that the amount (the amount of heat given to the refrigerant from the cooling water) becomes excessive, the balance of the amount of heat in the refrigerant circuit is lost, and the refrigerant pressure rises abnormally.

The present invention has been made in view of the above problems, and a purpose thereof is to realize heat exchange between a refrigerant and cooling water in proportion to the number of operating indoor heat exchangers (refrigerant flow rate) to achieve refrigerant An object of the present invention is to provide an engine-driven heat pump device capable of maintaining an appropriate heat transfer balance in the circuit.

[0006]

In order to achieve the above object, the invention according to claim 1 is a refrigerant circuit for circulating a refrigerant by a compressor driven by an engine and a cooling circuit for circulating cooling water for cooling the engine. It has a water circuit, an expansion valve, an indoor heat exchanger and an outdoor heat exchanger are provided in the refrigerant circuit, an exhaust gas heat exchanger is provided in the cooling water circuit, and heat exchange is performed between the refrigerant and the cooling water. In an engine-driven heat pump device comprising a double-tube heat exchanger provided between a refrigerant circuit and a cooling water circuit, a bypass circuit for bypassing a part of the cooling water flowing to the double-tube heat exchanger is provided. In addition to being provided, a water bypass valve is provided in the bypass circuit.

According to a second aspect of the present invention, in the first aspect of the invention, a radiator for cooling the cooling water is provided in the cooling water circuit, and the bypass circuit is used for the double pipe heat exchange of the cooling water circuit. It is characterized in that it is branched from the upstream side of the container and connected to the upstream side of the radiator.

According to a third aspect of the present invention, in the first or second aspect of the invention, a plurality of the indoor heat exchangers are provided and the water bypass valve is controlled according to the number of operating indoor heat exchangers. Characterize.

According to a fourth aspect of the invention, in the invention of the first, second or third aspect, the bypass of the cooling water by the bypass circuit is during heating operation, and the cooling water temperature is below a predetermined value. It is characterized by doing sometimes.

According to a fifth aspect of the present invention, there is provided a refrigerant circuit for circulating a refrigerant by a compressor driven by an engine and a cooling water circuit for circulating cooling water for cooling the engine, and the refrigerant circuit has an expansion valve. And an indoor heat exchanger and an outdoor heat exchanger, an exhaust gas heat exchanger is provided in the cooling water circuit, and a double pipe heat exchanger for exchanging heat between the refrigerant and the cooling water is provided as a refrigerant circuit. In an engine-driven heat pump device provided between cooling water circuits, a flow rate control valve for controlling the flow rate of cooling water flowing to the double-pipe heat exchanger, and at least cooling water temperature during heating operation, refrigerant pressure and Control means for controlling the opening of the flow control valve according to the number of operating indoor heat exchangers is provided.

[0011]

According to the first invention (the inventions according to claims 1 to 4), particularly during heating operation, when the number of operating indoor heat exchangers acting as condensers is small and the refrigerant flow rate is small, Since the water bypass valve is opened so that a part of the cooling water bypasses the double heat exchanger and flows to the bypass circuit, in the double pipe heat exchanger, the indoor heat exchanger in operation The amount of heat commensurate with the amount of heat radiation required for is given to the refrigerant from the cooling water. As a result, an appropriate heat transfer balance in the refrigerant circuit is realized, and various problems associated with overheating of the refrigerant are eliminated.

Further, according to the second invention (the invention according to claim 5), for example, in the heating operation, when the cooling water temperature is below a predetermined value, the number of operating indoor heat exchangers decreases, so that the refrigerant flow rate decreases. , Even if the amount of heat received per unit flow rate of the refrigerant (the amount of heat received from the cooling water in the double-tube heat exchanger) increases and the pressure rises, the control means should at least cool the temperature of the cooling water, the pressure of the refrigerant, and the indoor heat. In order to limit the flow rate of the cooling water to the double pipe heat exchanger by controlling the opening of the flow control valve according to the number of operating exchangers, in the double pipe heat exchanger, the indoor heat exchanger in operation The amount of heat commensurate with the amount of heat radiation required for is given to the refrigerant from the cooling water. As a result, an appropriate heat transfer balance in the refrigerant circuit is realized, and various problems associated with overheating of the refrigerant are eliminated.

[0013]

【Example】

[First invention] An embodiment of the first invention will be described below with reference to the accompanying drawings.

FIG. 1 is a circuit diagram showing the basic structure of an engine-driven heat pump device according to the first aspect of the invention, and FIG. 2 shows changes in the amount of cooling water flowing into each cooling water line (characteristics of a switching valve) depending on the cooling water temperature. It is a figure.

In FIG. 1, 1 is a water-cooled gas engine,
Reference numeral 2 is a compressor that is rotationally driven by the gas engine 1, and the output shaft 3 of the gas engine 1 is a pulley 4 and a belt 5.
And an input shaft 7 of the compressor 2 via a pulley 6.

An intake pipe 8 is connected to the intake system of the gas engine 1, and an air cleaner 9 and a mixer 10 are connected in the middle of the intake pipe 8. A fuel supply pipe 11 connected to a fuel gas supply source (not shown) is connected to the mixer 10, and two fuel gas solenoid valves 12 and a zero governor 13 are connected in the middle of the fuel supply pipe 11. ing.

An oil tank 15 is connected to the crank chamber of the gas engine 1 via an oil supply pipe 14. Furthermore, the breather pipe 16 which is led out from the gas engine 1
An oil separator 17 is connected to the gas line 18. After the breather gas discharged from the gas engine 1 has its oil component removed by the oil separator 17, the gas line 18
And is returned to the upstream side of the mixer 10 of the fuel supply pipe 11, and the oil component is returned to the crank chamber of the gas engine 1 through the oil line 19.

On the other hand, an exhaust pipe 20 extends from the exhaust system of the gas engine 1, and an exhaust gas heat exchanger 21 is provided in the exhaust pipe 20.

By the way, the present heat pump device is provided with a refrigerant circuit 22 forming a closed loop including the compressor 2 and a cooling water circuit 23 for circulating cooling water for cooling the gas engine 1.

The refrigerant circuit 22 is a circuit for circulating a refrigerant such as freon by the compressor 2, which is a refrigerant line 22a leading from the discharge side of the compressor 2 to the oil separator 24 and the oil separator 24. From the four-way valve 25 to a first outdoor heat exchanger (hereinafter abbreviated as an outdoor unit) 26-1 via a double-pipe heat exchanger 44 described later. Refrigerant line 2
2c, a refrigerant line 22d branching from the middle of the refrigerant line 22c to the second outdoor unit 26-2, the first outdoor unit 26-1 to the liquid gas heat exchanger 27, the dryer 28, the sight glass 29, and A refrigerant line 22e that reaches the expansion valve 31 through the strainer 30, a refrigerant line 22f that connects the second outdoor unit 26-2 and the refrigerant line 22e, and a plurality (n) of indoor heat from the expansion valve 31. Exchanger (hereinafter,
, 32-n, and a refrigerant line 22 from each of the outdoor units 32-1, ... 32-n to the four-way valve 25 via the strainer 33.
h, a refrigerant line 22i from the four-way valve 25 to the accumulator 35 through the liquid gas heat exchanger 27 and the silencer 34, and a refrigerant line 22j that is derived from the accumulator 35 and is connected to the suction side of the compressor 2. Has been done.

The oil return line 36 extending from the oil separator 24 is connected to the refrigerant line 22j. Further, a bypass line 22k is branched from the refrigerant line 22b, and the bypass line 22k
The bypass line 22m further branching from this is connected to the silencer 34, and each bypass line 22m
Bypass valves 37 and 38 are connected to k and 22m, respectively.

On the other hand, the cooling water line 23 extends from the discharge side of the water pump 39 to the cooling water inlet of the gas engine 1 through the exhaust gas heat exchanger 21.
And a cooling water line 23b led out from the cooling water outlet of the gas engine 1 to reach the switching valve 40 having a thermostat.
A cooling water line 23c led out from the switching valve 40 and connected to the inlet side of the radiator 42, a cooling water line 23d led out from the outlet side of the radiator 42, and a suction of the water pump 39 from the cooling water line 23d. The cooling water line 23e reaching the side, the cooling water supply line 23f reaching the water tank 43 from the cooling water line 23d, and the cooling water line 2 led out from the switching valve 40 and passing through the double pipe heat exchanger 44.
The cooling water line 23g connected to 3e is included. In FIG. 1, 23h is an air vent passage,
23i is a diaphragm.

By the way, in the present embodiment, the double pipe heat exchanger 44 is provided between the refrigerant circuit 22 and the cooling water circuit 23. In the double pipe heat exchanger 44, the refrigerant line 22c is provided. Heat exchange is performed between the flowing refrigerant and the cooling water flowing through the cooling water line 23g.

Thus, in this embodiment, the cooling water line 23
A bypass circuit 45 is provided for allowing a part of the cooling water flowing through g to bypass the double-tube heat exchanger 44 and flow. That is, the bypass circuit 45 is branched from the upstream side of the double pipe heat exchanger 44 of the cooling water line 23g and connected to the upstream side of the radiator 42 of the cooling water line 23c, and in the middle of the bypass circuit 45. Is provided with a water bypass valve 46.

As shown in FIG. 2, the switching valve 40 fully closes the cooling water line 23c and cools it when the cooling water temperature is, for example, 78 ° C. or lower by the action of the thermostat provided therein. The water line 23g is fully opened to flow the cooling water only to one cooling water line 23g, and when the cooling water temperature exceeds 78 ° C., the cooling water line 23c starts to open, while the cooling water line 23g starts to be closed to both cooling water lines 23c. , 23 g, and when the cooling water temperature exceeds 86 ° C., the cooling water line 23 c is fully opened, the cooling water line 23 g is fully closed, and the cooling water is flowed only in one cooling water line 23 c. Also, the water bypass valve 4
6 is during heating operation, and the indoor units 32-1 and
The opening degree is controlled according to the number of operating units of 32n.

Next, the operation of the heat pump device according to this embodiment will be described.

First, the operation during heating operation will be described. When the gas engine 1 is driven and the compressor 2 is rotationally driven by the gas engine 1, the gaseous refrigerant is compressed by the compressor 2 and high temperature is achieved. The high-pressure gaseous refrigerant reaches the oil separator 24 via the refrigerant line 22a. In the oil separator 24, the oil component contained in the refrigerant is removed, the refrigerant from which the oil component is removed reaches the four-way valve 25 through the refrigerant line 22b, and the oil separated from the refrigerant passes through the oil return line 36. The refrigerant line 22
returned to j.

By the way, during the heating operation, as shown by the solid line in FIG. 1, port a and port c of the four-way valve 25 are shown.
And the high-temperature high-pressure gaseous refrigerant are connected to the four-way valve 2
5 to the refrigerant line 22h side through the strainer 33.
, 32-n, through which the heat of condensation is released and liquefied, and the heat of condensation released at this time heats the room.

Then, as described above, the indoor units 32-1 and
The high-pressure refrigerant that has liquefied by releasing the heat of condensation in 32-n reaches each expansion valve 31, is decompressed by the expansion valve 31, then enters the refrigerant line 22g, and the strainer 30.
After flowing through the refrigerant line 22e through the dryer 28 and the dryer 28 and after passing through the liquid gas heat exchanger 27, it reaches the first and second outdoor units 26-1 and 26-2 where the heat of vaporization is taken from the outside air. Vaporize. The liquid-gas heat exchanger 27 mainly discharges the residual heat of the refrigerant liquefied by releasing the heat of condensation in the outdoor units 26-1, 26-2 during cooling in the indoor units 32-1, ..., 32-n. This is for increasing the cooling efficiency by absorbing the evaporation heat and absorbing it in the vaporized refrigerant, and has a low heat exchange function during heating.

On the other hand, the cooling water circulated in the cooling circuit 23 by driving the water pump 39 is discharged from the water pump 39 and flows through the cooling water line 23a, and in the middle thereof, in the exhaust gas heat exchanger 21, the gas engine 1 After the heat of the exhaust gas discharged from the exhaust pipe 20 is recovered and heated, it flows through a water jacket (not shown) of the gas engine 1 to cool the gas engine 1. Then, the cooling water used for cooling the gas engine 1 flows through the cooling water line 23b and reaches the switching valve 40.

Here, as described above, the switching valve 40 connects the cooling water line 23 to the cooling water line 23 when the cooling water temperature is 78 ° C. or lower.
cTo fully close the other cooling water line 23g,
The cooling water flows through the cooling water line 23g.

By the way, the water bypass valve 46 provided in the bypass circuit 45 has the indoor units 32-1, ..., As described above.
The opening degree is controlled by the number of operating units (heat load) of 32-n, and as described above, all the indoor units 32-1, ..., 32-
When n is in operation, it is closed, and all the cooling water flows through the double-pipe heat exchanger 44 to heat the vaporized gaseous refrigerant in the outdoor units 26-1 and 26-2 during heating operation. . As a result, the waste heat of the engine 1 (a part of the heat of the exhaust gas) is recovered by the refrigerant, and the gaseous refrigerant that has recovered this waste heat flows through the refrigerant line 22c and reaches the four-way valve 25. The cooling water that has passed through the double tube heat exchanger 44 is sucked by the water pump 39 through the cooling water line 23e, and the same operation is repeated thereafter.

During the heating operation, since the port b and the port d of the four-way valve 25 are communicated with each other as shown by the solid line in FIG. 1, the refrigerant flows through the refrigerant line 22i and the liquid gas heat exchanger. An accumulator 35 is passed through 27 and a silencer 34.

In the accumulator 35, the gas and liquid of the refrigerant are separated, and only the gaseous refrigerant is supplied to the refrigerant line 22.
The refrigerant sucked from j to the suction port of the compressor 2, and the sucked refrigerant is compressed again by the compressor 2 to repeat the same operation as described above.

Thus, in this embodiment, the cooling water temperature is 78 ° C. or lower, and all the indoor units 32-1, ..., 32-
When operating n, all the waste heat of the gas engine 1 collected by the cooling water is given to the refrigerant and added to the heat radiation amount of each indoor unit 32-1, ..., 32-n, so that heating is performed. The effect is enhanced.

On the other hand, when the cooling water temperature is 78 ° C. or less and the refrigerant flow rate is small because, for example, only one indoor unit 32-1 is operating, the water bypass valve 46 of the bypass circuit 45 is opened. Therefore, a part of the cooling water flowing through the cooling water line 23g bypasses the double-pipe heat exchanger 44 and flows through the bypass circuit 45, and is not used for heating the refrigerant flowing through the refrigerant line 22c. It is sent to the radiator 42 and cooled.

When the required heat load (the amount of heat dissipated by one indoor unit 32-1) is small as described above, a part of the cooling water bypasses the double pipe heat exchanger 44, so In the heavy pipe heat exchanger 44, the amount of heat commensurate with the required heat load is given from the cooling water to the refrigerant, and as a result, the refrigerant circuit 2
A proper heat transfer balance in the inside of 2 is realized, and various problems due to overheating of the refrigerant are eliminated.

In this embodiment, the bypass circuit 4
Since 5 is connected to the cooling water line 23c on the inlet side of the radiator 42, the cooling water flowing in the bypass circuit 45 is cooled in the radiator 42, and as a result, the double pipe heat exchanger 4
The heat transfer amount in 4 can be reduced and the object can be achieved.
Further, a part of the cooling water flowing from the switching valve 40 to the cooling water line 22g is made to flow to the cooling water line 23c, and the flow rate of the cooling water flowing to the radiator 42 is increased, so that the cooling water can be further cooled. . The bypass circuit 45 may be connected to the cooling water line 23d on the outlet side of the radiator 42.

On the other hand, when the cooling water temperature exceeds 78 ° C., as described above (see FIG. 2), the switching valve 40 begins to open one cooling water line 23c, while the other cooling water line 22g.
In order to start closing, the cooling water flows through both cooling water lines 23c and 23g, and at this time also, in the double pipe heat exchanger 44, a part of the waste heat of the gas engine 1 is given from the cooling water to the refrigerant.

When the cooling water temperature exceeds 86 ° C.,
As described above (see FIG. 2), since the switching valve 40 fully opens one cooling line 23c and completely closes the other cooling line 23g, the heat between the cooling water and the refrigerant in the double-tube heat exchanger 44 is changed. No replacement is done and all cooling water is in the cooling line 2
It is sent to the radiator 42 through 3c and cooled.

Next, the operation during the cooling operation will be outlined. Since the cooling water temperature becomes 86 ° C. or higher during the cooling operation, the cooling water flows through the double pipe heat exchanger 44 due to the operation of the switching valve 40. Therefore, the waste heat of the gas engine 1 is not recovered by the refrigerant, all the cooling water flows from the cooling water line 23c to the radiator 42, and the cooling water is sufficiently cooled.

The high-temperature high-pressure gaseous refrigerant compressed by the compressor 2 reaches the four-way valve 25 through the refrigerant line 22a, the oil separator 24 and the refrigerant line 22b.

By the way, during the cooling operation, as shown by the broken line in FIG. 1, port a and port b of the four-way valve 25,
Since the port c and the port d are communicated with each other, the high-temperature and high-pressure gaseous refrigerant reaches the outdoor units 26-1 and 26-2 through the refrigerant line 22c, where it is cooled and condensed by the outside air to generate high pressure. Liquid refrigerant of the cooling line 22e,
22f flowing along the liquid gas heat exchanger 27, the dryer 2
After passing through the strainer 8 and the strainer 30, the expansion valve 31 is reached and the pressure is reduced by the expansion valve 31.

The depressurized refrigerant is used as the indoor unit 32-
In 1, ..., 32-n, latent heat of vaporization is taken from the air in the room to evaporate, so that the air in the room is cooled and the room is cooled. The refrigerant vaporized by evaporation is the refrigerant line 22.
c, 22d, the four-way valve 25, the refrigerant line 22i, the liquid-gas heat exchanger 27 and the silencer 34, and the accumulator 35, where gas and liquid are separated.
The gaseous refrigerant is sucked into the compressor 2 through the refrigerant line 22j, and the refrigerant sucked in the compressor 2 is compressed again and the above-described operation is repeated. [Second Invention] Next, an embodiment of the second invention will be described with reference to FIGS. 3 is a circuit diagram showing the basic configuration of the engine-driven heat pump device according to the second aspect of the invention, FIG. 4 is a block diagram showing the configuration of the control system of the linear three-way valve, and FIG. 5 is the configuration of the linear three-way valve. Sectional drawing, FIG. 6 is an opening characteristic diagram of the linear three-way valve, FIG. 7 is a control characteristic diagram of the opening coefficient α with respect to the cooling water temperature t, and FIG. 8 is a control characteristic diagram of the opening coefficient β with respect to the operating indoor unit capacity Q. FIG. 9 is a control characteristic diagram of the opening coefficient γ with respect to the discharge side pressure P of the refrigerant.

The heat pump device according to the present invention, as shown in FIG. 3, has the bypass circuit 4 in the embodiment of the first invention.
5 and the water bypass valve 46 are abolished, and the switching valve 40 (see FIG. 1)
Instead of the linear three-way valve 110, the linear three-way valve 1
A cooling water temperature sensor 111 for detecting the temperature t of the cooling water flowing therethrough is provided on the upstream side of 10, and a refrigerant discharge side pressure P for controlling the linear three-way valve 110 is provided in the middle of the refrigerant line 22a. Pressure sensor 112 for detection
Since other configurations are similar to those of the first embodiment of the present invention, in FIG. 3, the same elements as those shown in FIG. 1 are denoted by the same reference numerals. The description is omitted.

By the way, the linear three-way valve 110, the cooling water temperature sensor 111 and the pressure sensor 112 are connected to a control device (hereinafter referred to as CPU) 120 shown in FIG. 4, and the CPU 120 detects the cooling water temperature sensor 111. Cooling water temperature t, indoor units 32-1, 32-2,
The number of operating units of 32-n (operating indoor unit capacity Q, that is,
Of the indoor units 32-1, 32-2, ..., 32-n, the amount of heat proportional to the sum of the differences between the indoor temperature and the set temperature of each room in which the operating indoor unit is installed), a pressure sensor 1
The opening degree of the linear three-way valve 110 is controlled based on the refrigerant discharge side pressure P detected by 12 and the cooling / heating operation information (information indicating whether the operation is the cooling operation or the heating operation).

The structure and opening characteristic of the linear three-way valve 110 will be described with reference to FIGS. 5 and 6.

As shown in FIG. 5, the linear three-way valve 110 is constructed by rotatably incorporating a rotary valve body 114 in a housing 113, and a flow passage 113g connected to the cooling water line 23g is formed in the housing 113. Flow paths 113c connected to the cooling water line 23c are formed facing each other.

A circular hole-shaped cooling water inlet 114b is formed in the center of the valve body 114 so as to be connected to the cooling water line 23b, and the flow passages 113g and 113c are provided on both sides of the cooling water inlet 114b. Flow path 114 that opens to each
g, 114c are formed.

Thus, the flow path 114g of the valve body 114,
When the opening areas of 114c to the flow passages 113g and 113c are A ₁ and A ₂ , respectively, as shown in FIG. 6, the opening area A ₁ is the valve opening θ (the rotation angle of the valve body 114 (0 ° to 90
°)) increases linearly, and conversely the opening area A ₂
Increases linearly as the valve opening θ increases, and the sum of the two (A
₁ + A ₂ ) is a constant value A ₀ (= A ₁ ) regardless of the valve opening θ.
+ A ₂ ).

By the way, the opening areas A ₁ and A ₂ of the linear three-way valve 110 are calculated by the following equation;

[0052]

[Number 1] _{A 1 = (a 1/100} ) × A 0 ... (1) A 2 = (a 2/100) when determined by × A ₀ ... (2), the coefficient (hereinafter, referred to as opening) a
₁ and a ₂ are calculated by the CPU 120 according to the following equations.

[0053]

[Formula 2] a ₁ = α ・ β ・ γ ・ ε × 100 (3) a ₂ = 100−a ₁ (4) α, β, γ, ε in the above equation (3) are opening coefficients. Then, α (0 ≦ α ≦ 1) changes as shown in FIG. 7 depending on the cooling water temperature t detected by the cooling water temperature sensor 111, and the cooling water temperature t is t _L (for example, 60 ° C.) or less (t ≦
In the region of t _L ), α = 1 is maintained, and the cooling water temperature t is t _L
Above t _h (eg 80 ° C.) and below the region (t _L <t
In <t _H ), the temperature decreases linearly with the increase of the cooling water temperature t, and α = 0 is maintained in the region where the cooling water temperature t is t _H or higher (t ≧ t _H ).

The opening coefficient β (0 ≦ α ≦ 1) changes with respect to the operating indoor unit capacity Q as shown in FIG. 8, and increases in proportion to the increase of the operating indoor unit capacity Q.

Further, the opening coefficient γ (0 ≦ α ≦ 1) changes as shown in FIG. 9 with respect to the refrigerant discharge side pressure P detected by the pressure sensor 112, and linearly decreases as the pressure P increases. To do.

The opening coefficient ε is ε = 0 during cooling operation,
During heating operation, ε = 1 is set.

Thus, in the equations (3) and (4), the opening a ₁ ,
When a ₂ is calculated and the opening areas A ₁ and A _{2 of the} linear three-way valve 110 are obtained by the above equations (1) and (2) based on the opening a ₁ and a ₂ , the cooling water line 23b The flow rate I ₀ of the cooling water flowing through the linear three-way valve 110 flows through the cooling water lines 23g and 23c at a rate of the flow rates I ₁ and I ₂ , and the flow rates I ₁ and I ₂ are obtained by the following equations.

[0058]

(3) I ₁ = I ₀ × A ₁ / (A ₁ + A ₂ ) ... (5) I ₂ = I ₀ × A ₂ / (A ₁ + A ₂ ) = I ₀ −I ₁ (6) Above During the cooling operation, heat exchange between the refrigerant and the cooling water in the double-tube heat exchanger 44 is not required, so the opening coefficient ε = 0 is set, and as a result, from the equations (3) and (4), a ₁ = 0, a ₂ = 100, and the (1), and _{a 1 = 0, a 2 =} a 0 from equation (2). Therefore, (5),
From equation (6), the flow rates I ₁ and I ₂ of the cooling water flowing through the cooling water lines 23g and 23c are I ₁ = 0 and I ₂ = I ₀ , respectively, and all the cooling water flows through the cooling water line 23c. Is not used for heating the refrigerant in the double-tube heat exchanger 44.

On the other hand, during the heating operation, during the normal operation in which the cooling water temperature t is equal to or lower than the predetermined value t _L (t ≦ t _L ) (all indoor units 32-1, 32-2, ..., 32-n are (During operation), the opening degrees α, β, γ, ε are all set to 1 (α = β = γ = ε = 1), so (3),
From equation (4), a ₁ = 100 and a ₂ = 0, and (1),
From the equation (2), A ₁ = A ₀ and A ₂ = 0. Therefore,
From equations (5) and (6), the flow rates I ₁ and I ₂ of the cooling water flowing through the cooling water lines 23g and 23c are I ₁ = I ₀ and I ₂ , respectively.
= 0, all of the cooling water flows through the cooling water line 23g, and all of the waste heat of the gas engine 1 recovered by the cooling water is given to the refrigerant in the double-tube heat exchanger 44 and each indoor unit 32-1. , 32-2, ..., 32-n are added to the heat radiation amount, the heating effect is enhanced.

On the other hand, during the heating operation, the indoor units 32-1 and 32
The operating indoor unit capacity Q decreases due to the decrease in the number of operating units of −2, ..., 32-n, and accordingly the flow rate of the refrigerant circulating in the refrigerant circuit 22 decreases, and the heat reception amount per unit flow rate of the refrigerant ( When the heat quantity received from the cooling water in the double-tube heat exchanger 44 increases and the discharge side pressure P increases, both the opening degrees β and γ are set to be small as shown in FIG. 3) the opening area a ₁ is reduced to be obtained in opening a ₁ and (1) obtained by formula, obtained in (4) at the opening a ₂ obtained (2) opening On the contrary, the area A ₂ becomes large. Therefore, the flow rate I _{1 of the} cooling water flowing through the cooling water line 23g calculated by the equation (5) is reduced, and the flow rate of the cooling water to the double heat exchanger 44 is limited.
In the double-tube heat exchanger 44, the indoor units 32-1 and 32
The amount of heat corresponding to the amount of heat radiation required for the number of operating units of −2, ..., 32-n is given to the refrigerant from the cooling water, and as a result, an appropriate heat transfer balance in the refrigerant circuit 22 is achieved as in the first invention. This is realized, and various problems caused by overheating of the refrigerant are eliminated. In this case, the cooling water having the flow rate I ₂ flowing through the cooling water line 23c is not used for heating the refrigerant and is sent to the radiator 42 to be cooled, so that the cooling water temperature t detected by the cooling water temperature sensor 111 decreases. A proper heat transfer balance in the refrigerant circuit 22 is realized.

Even in the region where the cooling water temperature t is t _L <t <t _H , the cooling water line 23 is in the initial state.
The only difference is that the cooling water flows through both g and 23c, and the other operating principle is when t ≦ t _L (α =
It is the same as the above-mentioned operating principle in 1).

As described above, also in the present invention, the first
Although the same effect as the invention can be obtained, in particular, in the present invention, by using the linear three-way valve 110, the bypass circuit 45 and the water bypass valve 46 in the embodiment of the first invention are obtained.
Since the cooling water circuit 23 can be simplified (see FIG. 1), a unique effect can be obtained.

[0063]

As is apparent from the above description, during the heating operation, when the refrigerant flow rate is small because the number of indoor heat exchangers acting as condensers is small, the first invention provides: The water bypass valve may be opened so that a part of the cooling water bypasses the double heat exchanger and flows into the bypass circuit, and according to the second aspect of the invention, the control means includes at least the cooling water temperature, The opening of the flow control valve is controlled according to the refrigerant pressure and the number of operating indoor heat exchangers to limit the flow rate of the cooling water to the double heat exchanger. The cooling water gives the refrigerant an amount of heat commensurate with the amount of heat required for the indoor heat exchanger, which results in an appropriate heat transfer balance in the refrigerant circuit, eliminating various problems associated with overheating of the refrigerant. The effect is obtained.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a basic configuration of an engine-driven heat pump device according to a first invention.

FIG. 2 is a diagram showing changes in the amount of cooling water flowing to each cooling water line (characteristics of a switching valve) depending on the cooling water temperature.

FIG. 3 is a circuit diagram showing a basic configuration of an engine-driven heat pump device according to a second invention.

FIG. 4 is a block diagram showing a configuration of a control system of a linear three-way valve.

FIG. 5 is a sectional view showing a configuration of a linear three-way valve.

FIG. 6 is an opening characteristic diagram of a linear three-way valve.

FIG. 7 is a control characteristic diagram of the opening coefficient α with respect to the cooling water temperature t.

8 is a control characteristic diagram of the opening coefficient β with respect to the operating indoor unit capacity Q. FIG.

FIG. 9 is a control characteristic diagram of the opening coefficient γ with respect to the refrigerant discharge side pressure P.

[Explanation of symbols]

 1 Gas Engine (Engine) 2 Compressor 21 Exhaust Gas Heat Exchanger 22 Refrigerant Circuit 23 Cooling Water Circuit 26-1, 26-2 Outdoor Unit (Outdoor Heat Exchanger) 31 Expansion Valve 32-1, 32-n Indoor Unit ( Indoor heat exchanger) 42 Radiator 44 Double tube heat exchanger 45 Bypass circuit 46 Water bypass valve 110 Linear three-way valve (flow control valve) 111 Cooling water temperature sensor 112 Pressure sensor 120 CPU (control means)

Claims (5)

[Claims] 1. A refrigerant circuit that circulates a refrigerant by a compressor driven by an engine, and a cooling water circuit that circulates cooling water that cools the engine, wherein the refrigerant circuit includes an expansion valve, an indoor heat exchanger, and An outdoor heat exchanger is provided, an exhaust gas heat exchanger is provided in the cooling water circuit, and a double pipe heat exchanger for exchanging heat between the refrigerant and the cooling water is provided between the refrigerant circuit and the cooling water circuit. An engine-driven heat pump device provided, wherein a bypass circuit for bypassing a part of the cooling water flowing to the double-tube heat exchanger is provided, and a water bypass valve is provided in the bypass circuit. Driven heat pump device. 2. A radiator for cooling the cooling water is provided in the cooling water circuit, and the bypass circuit branches from an upstream side of the double pipe heat exchanger of the cooling water circuit to an upstream side of the radiator. The engine-driven heat pump device according to claim 1, wherein the heat pump device is driven by an engine. 3. The engine-driven heat generator according to claim 1, wherein a plurality of the indoor heat exchangers are provided, and the water bypass valve is controlled according to the number of operating indoor heat exchangers. Pump device. 4. The bypass of the cooling water by the bypass circuit is performed during the heating operation and when the cooling water temperature is equal to or lower than a predetermined value.
The engine-driven heat pump device described. 5. A refrigerant circuit for circulating a refrigerant by a compressor driven by an engine, and a cooling water circuit for circulating a cooling water for cooling the engine, wherein the refrigerant circuit includes an expansion valve, an indoor heat exchanger, and An outdoor heat exchanger is provided, an exhaust gas heat exchanger is provided in the cooling water circuit, and a double pipe heat exchanger for exchanging heat between the refrigerant and the cooling water is provided between the refrigerant circuit and the cooling water circuit. In an engine-driven heat pump device that is provided, a flow rate control valve that controls the flow rate of the cooling water flowing to the double-pipe heat exchanger, at least the cooling water temperature during the heating operation, the refrigerant pressure, and the indoor heat exchanger. An engine-driven heat pump device comprising a control means for controlling the opening of the flow control valve according to the number of operating units.