JPH03213966A - Waste heat recoverying heat pump - Google Patents

Abstract

PURPOSE:To improve a heating capability in winter season without extending a cooling water circuit up to an indoor device of a G gas engine driving type heat pump by a method wherein a heat exchanging operation is carried out between the cooling circuit and the heat pump circuit. CONSTITUTION:A cooling circuit 12 is formed in general so as to connect an interior of a gas engine 11 with a hot water-refrigerant heat exchanger 14. Since the heat exchanging capability of the hot water-refrigerant heat exchanger 14 has a certain limitation, a sufficient cooling may not be attained by the cooling circuit 14 and a cooling of the gas engine 11 has a certain trouble, resulting in that a cooling circuit 12 is formed so as to connect the interior of the gas engine 11 with a radiator 13. In this case, after the refrigerant of the refrigerant operating chamber 14a is filled in liquid form, the control valve 31 keeps closed until the over-heating state is attained. Then, the heat exchanging operation is carried out in the hot water-refrigerant heat exchanger 14. Then, as the temperature detected by a temperature sensor 35 is higher than a temperature outputted from the temperature sensor 37, the control means 32 judges that the refrigerant in the refrigerant operating chamber 14a is in its over- heated state and then it opens the control valve 31 and the operating chamber 14a is replaced with the liquid refrigerant.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an exhaust heat recovery type heat pump, and is used, for example, in a near conditioner configured with a gas engine-driven heat pump device. .

(Prior art) Near conditioners (hereinafter abbreviated as GHP) have conventionally been constructed using gas engine-driven heat pump devices.
It is known to utilize the exhaust heat of a gas engine to improve the heating capacity in winter.

For example, in the "Aisin Seiki 10 Horsepower Gas Heat Pump Air Conditioner Service Manual" published in July 1989, the gas engine cooling water circuit installed in the GHP's outdoor unit is connected to the GHP's indoor unit. The heat of the high-temperature cooling water is radiated through an indoor heat exchanger separate from the heat pump circuit, and serves as an auxiliary heat source for indoor heating.

(Problem to be Solved by the Invention) However, in the GHP using the above-mentioned method, the piping between the outdoor unit and the indoor unit is two pipes for reciprocating the heat pump circuit and two pipes for reciprocating the cooling water circuit. Therefore, a total of four pipelines are required, which has the disadvantage that the GHP installation work is time-consuming and the installation cost is high.

Therefore, the technical objective of the present invention is to improve the heating capacity in winter without extending the cooling water circuit to the indoor unit side of the GHP.

[Structure of the invention]

(Means for Solving the Problems) The technical means of the present invention taken to solve the above-mentioned technical problems of the present invention include a combustion engine, a compressor driven by the combustion engine, and a compressor connected to the compressor. 1st
A refrigerant circuit including a heat exchanger, an expansion valve connected to the first heat exchanger, a second heat exchanger connected to the expansion valve, and a compressor connected to the second heat exchanger; It has a cooling circuit composed of a third heat exchanger and a fourth heat exchanger that circulate within the combustion engine and are connected in parallel with the combustion engine, and the third heat exchanger has a first working chamber and a fourth heat exchanger. Consisting of two working chambers, the first working chamber receives a first working fluid that circulates within the refrigerant circuit, and the second working chamber receives a second working fluid that circulates within the cooling circuit.
A working fluid is introduced, and the suction side of the first working chamber is connected between the first heat exchanger and the expansion valve via the first check valve.
The discharge side of the working chamber is connected to the discharge side of the compressor via a second check valve, and the suction side of the compressor is connected via a control valve whose opening and closing are controlled by a control means. .

(Function) According to the technical means of the present invention described above, heat exchange can be performed with high efficiency between the cooling circuit and the heat pump circuit, and the cooling water circuit can be extended to the indoor unit side of the GHP. (It is possible to improve the heating capacity in winter.

(Example) Hereinafter, an example embodying the technical means of the present invention will be described based on the accompanying drawings.

FIG. 1 shows an exhaust heat recovery type heat pump 10 according to an embodiment of the present invention. FIG. 2 shows an explanatory diagram of the hot water-refrigerant heat exchanger 14.

A passage cavity is formed in a cylinder block (not shown) of the gas engine 11 to radiate heat generated by combustion of the gas engine 11 to cooling water. A cooling circuit 12 of this gas engine 11 connects a radiator 13 and a hot water-refrigerant heat exchanger 4 in parallel. Further, a pump 15 and a switching valve 16 are disposed in the middle of the cooling circuit 12.

The compressor 17 is driven by the gas engine 11,
Its discharge side 17a is connected to one end of an indoor heat exchanger 19 via a four-way valve 18. In addition, the indoor heat exchanger 19
The other end has four check valves 20a, 20b, 20c, 20d.
It is connected to a receiver 21 via a manifold valve 20 configured by. Next, the output side 2xa of the receiver 210m is connected to an outdoor heat exchanger 24 via a filter dryer 22, an expansion valve 23, and a manifold valve 20. Further, one end of the outdoor heat exchanger 24 is connected to the inlet side 25b of the accumulator 25 via a four-way valve, and the outlet side 25a of the accumulator 25 is connected to the suction side 17b of the compressor 17, so that the inside is connected to the inlet side 25b of the accumulator 25. constitutes a heat pump 26 that circulates.

The hot water-refrigerant heat exchanger 14 includes a refrigerant working chamber 14a and a hot water working chamber 14b. Here, a gas engine 11 circulating in the cooling circuit 12 is provided in the hot water working chamber 14b.
cooling water is circulating.

On the other hand, the inlet 27 of the refrigerant working chamber 14a is connected to the outflow side 21a of the receiver 21 via a check valve 28. Further, the outlet 29 of the refrigerant working chamber 14a is divided into two parts, one of which is connected to the discharge side 17a of the compressor 17 via a check valve 30, and the other is a control valve whose opening and closing are controlled by a control means 32. 31 to the inflow side 25b of the accumulator 25.

The control means 32 also includes three temperature sensors 3536.3.
The output signal output by No. 7 is input. That is, a temperature sensor 35 disposed at a branch point 38 beyond the outlet 29 of the refrigerant working chamber 14a, and a pipe 3 connecting the outlet 29 and the control valve 31.
The temperature sensor 36 disposed at one end of the constriction part 34 formed in the middle of the temperature sensor 36 and the liquid refrigerant discharge side (
This is a temperature sensor 37 disposed during heating.

The operation of the exhaust heat recovery heat pump 10 having the above configuration will be described below.

This exhaust heat recovery type heat pump 10 is used as a near conditioner as described above, and its operation will also be explained based on the near conditioner.

Figure 1 shows the heating status of the near conditioner.
The high temperature discharged from the discharge side 17a of the compressor 17
The high-pressure gaseous refrigerant flows into the indoor heat exchanger 19 via the four-way valve 18, where the heat in the refrigerant is radiated into the room for heating.

Thereafter, the refrigerant radiates heat and becomes a high-temperature, high-pressure liquid refrigerant, passing through the check valve 20c in the manifold valve 20 and flowing into the receiver 21.

The high-temperature, high-pressure liquid refrigerant flowing out from the receiver 21 is divided into two directions.

One refrigerant passes through the filter dryer 22 to the expansion valve 23.
At this expansion valve 23, the refrigerant becomes a low-temperature, low-pressure gas-liquid refrigerant. This refrigerant should be able to flow into any of the check valves 20a, 20b, and 20d in the manifold valve 20, but since the outlet sides of the check valves 20a and 20d are in a high temperature and high pressure state, the refrigerant in a low temperature and low pressure state will flow out. It is not possible.

Therefore, the refrigerant that has passed through the expansion valve 23 is transferred to the outdoor heat exchanger 24.
flows out to.

In the outdoor heat exchanger 24, the low-temperature, low-pressure gas-liquid refrigerant absorbs heat from the outside air and becomes a low-temperature, low-pressure gaseous refrigerant. Thereafter, the refrigerant flows into the accumulator 25 via the check valve 18 and then circulates to the compressor 17.

Now, the other refrigerant branched from the receiver 2'1 is passed through the check valve 28 to the refrigerant working chamber 14 of the hot water-refrigerant heat exchanger 14.
lead to a. Here, the control valve 31 is controlled to open and close by the control means 32, and the control means 32 opens the control valve 31 when the refrigerant in the refrigerant working chamber 14a becomes overheated (all of it becomes a gas phase due to evaporation). Therefore, the liquid refrigerant is rapidly stored in the refrigerant working chamber 14a, and when the refrigerant working chamber 14a is filled with the liquid refrigerant, the control means 32 senses this and closes the control valve 31. At this time, since hot water in the cooling circuit 12 is circulating in the hot water working chamber 14b of the hot water-refrigerant heat exchanger 14, heat exchange progresses between the hot water and the liquid refrigerant, and the liquid refrigerant gradually becomes gas. It's becoming more and more. During this gasification process, a check valve 30 is installed inside the refrigerant working chamber 14a.
The gaseous refrigerant is discharged from the check valve 30 to the discharge side 17a of the compressor 17, and the indoor heat exchanger 19 radiates heat into the room.

Therefore, in the indoor heat exchanger 19, the refrigerant is transferred to the outdoor heat exchanger 2.
Since not only the heat obtained in step 4 but also the heat obtained in the hot water-refrigerant heat exchanger 14 is radiated, the heating capacity can be improved.

Thereafter, when all the refrigerant in the refrigerant working chamber 14a is gasified and becomes overheated, the control valve 31 is opened by the control means 32, and substantially the entire gaseous refrigerant is discharged to the inlet side 25b of the accumulator 25.

Naturally, this refrigerant also radiates heat in the indoor heat exchanger 19, so it is useful for improving heating capacity.

At this time, the refrigerant in the refrigerant working chamber 14a escapes from the control valve 31 and at the same time the pressure in the refrigerant working chamber 14a decreases, so the refrigerant flows from the receiver 21 through the check valve 2 and into the refrigerant working chamber 14a. When the liquid refrigerant is rapidly stored and the refrigerant working chamber 14a is filled with the liquid refrigerant, the control means 32 senses this and closes the control valve 31, thus repeating the heat exchange cycle described above.

The switching valve 16 is switched and controlled by a control means (not shown), and normally the cooling circuit 12 is formed to connect the inside of the gas engine 11 and the hot water-refrigerant heat exchanger 14, and the hot water-refrigerant heat exchanger 14 is connected to the inside of the gas engine 11. Since there is a dust boundary in the heat exchange capacity of the heat exchanger 14, if the cooling water in the cooling circuit 12 is not sufficiently cooled by the hot water-refrigerant heat exchanger 14 and cooling of the gas engine 11 is hindered, the gas engine 11 A cooling circuit 12 is formed to connect the inside and the radiator 13.

Here, how the control means 32 controls the refrigerant working chamber 1
Is the refrigerant in the refrigerant working chamber 14 overheated?
A method for determining whether or not a is filled with liquid refrigerant will be explained.

First, in the former detection method, after the refrigerant in the refrigerant working chamber 14a is filled with liquid, the control valve 31 is closed until it becomes overheated, and heat exchange proceeds in the hot water-refrigerant heat exchanger 14. . At this time, the control means 32 controls the temperature sensors 35 and 37.
, and if the temperature detected by the temperature sensor 35 becomes higher than the temperature output by the temperature sensor 37 even considering the supercooling temperature, naturally the refrigerant working chamber 14a
It can be determined that the refrigerant inside is in an overheated state. Therefore, at this time, the control means 32 opens the control valve 31.

Next, in the latter detection method, the superheated refrigerant in the refrigerant working chamber 14a escapes through the opened control valve 31 (at the same time, the liquid refrigerant accumulates in the refrigerant working chamber 14a due to the negative pressure and is completely removed). After the refrigerant is filled, the overflowing refrigerant flows out into the pipe line 33. At this time, the liquid refrigerant attempts to gasify in the constriction part 34 due to the action of the constriction part 34 and absorbs external heat, so that the temperature sensor 35 detects the liquid refrigerant. The temperature detected by the temperature sensor 36 becomes lower than the temperature. Therefore, the control means 32 detects this and closes the control valve 31.

On the other hand, although the cooling state of the near conditioner is not shown,
The configuration of the exhaust heat recovery type heat pump 1o is as follows.

That is, the connection state of the four-way valve 18 is switched, the discharge side 17a of the compressor 17 and the outdoor heat exchanger 24 are connected, and the indoor heat exchanger 19 and the accumulator 25 are connected.
The inflow side 25b of the inflow side 25b is connected.

In the cooling state, the control valve 31 is always closed, and even if all the refrigerant in the refrigerant working chamber 14a of the hot water-refrigerant heat exchanger 14 is gasified and becomes overheated, the control valve 31 will not open. No new liquid refrigerant flows into the refrigerant working chamber 14a from the receiver 21. Therefore, the hot water-refrigerant heat exchanger 14 does not operate in the cooling state.

FIG. 3 shows another configuration of the cooling circuit, in which a thermostatic valve 50 is installed in the cooling circuit 1 in place of the switching valve 16 in FIG.
2, and as the cooling water temperature rises, the radiator 1
The amount of cooling water flowing to 3 is increased.

Furthermore, FIG. 4 shows another configuration of the cooling circuit, in which a thermostatic valve 62 is disposed at the engine 11 outlet of the cooling water circuit 60, and a bypass passage 63 having a throttle valve 64 in the middle is connected to the water It extends to the upstream side of the pump 65.

In addition, an exhaust gas heat exchanger 6 is provided in the exhaust pipe line of the engine 11.
1 is provided, and is connected in parallel with the engine 11 in the middle of a cooling water circuit 60 connected to the engine 11.

Hot water-refrigerant heat exchanger 14 disposed in cooling water circuit 60
The radiator 13 and the bypass passage 66 are connected in parallel and connected in series via a thermostatic valve 67.

〔Effect of the invention〕

As shown above, in the present invention, it is possible to perform heat exchange with high efficiency between the cooling circuit and the heat pump circuit, and the heating capacity in winter can be improved without extending the cooling water circuit to the indoor unit side of the GHP. It becomes possible to improve the

[Brief explanation of drawings]

FIG. 1 shows an exhaust heat recovery type heat pump 10 according to an embodiment of the present invention. FIG. 2 shows an explanatory diagram of the hot water-refrigerant heat exchanger 14. FIG. 3 shows an explanatory diagram of another configuration of the cooling circuit. FIG. 4 shows an explanatory diagram of another configuration of the cooling circuit. 10...Exhaust heat recovery heat pump, 11...Gas engine (combustion engine), 12...Cooling circuit, 13...Radiator (fourth heat exchanger), 14...Hot water-medium heat Exchanger (third heat exchanger), 14a... First working chamber, 14b... Second working chamber, 17... Compressor, 18... Four-way valve, 19...
...Indoor heat exchanger (first heat exchanger), 21...Receiver, 24...Outdoor heat exchanger (second heat exchanger), 25...
・Accumulator, 28... first check valve, 30... second check valve, 31...
...Control valve, 32...Control means.

Claims (2)

[Claims] (1) A combustion engine, a compressor driven by the combustion engine, a first heat exchanger connected to the compressor, an expansion valve connected to the first heat exchanger, and an expansion valve connected to the expansion valve. a refrigerant circuit configured by a second heat exchanger and the compressor connected to the second heat exchanger; and a third heat exchanger that circulates within the combustion engine and is connected in parallel with the combustion engine. the third heat exchanger is composed of a first working chamber and a second working chamber, and the first working chamber includes a refrigerant circuit. A circulating first working fluid is introduced into the second working chamber, a second working fluid circulating within the cooling circuit is introduced into the second working chamber, and a suction side of the first working chamber is connected to the first heat exchanger and the expansion chamber. The discharge side of the first working chamber is connected to the discharge side of the compressor via a second check valve, and the discharge side of the compressor is connected to the suction side of the compressor. An exhaust heat recovery type heat pump that is connected via a control valve that is opened and closed by a control means. (2) the control means opens the control valve when all the first working fluid in the first working chamber has evaporated;
The exhaust heat recovery type heat pump according to claim 1, wherein the control valve is closed when the first working chamber is filled with the first liquid working fluid.