JPS616557A - Engine heat pump device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine heat pump device for an engine-driven air conditioning system.

[Prior art]

Among conventional air-conditioning and heating systems that utilize an engine heat pump system driven by an engine such as an internal combustion engine, the type that directly exchanges heat from the refrigerant indoors, such as the air conditioner, uses waste heat from the engine recovered during heating. The following methods are used to add to the heating output.

In other words, there are systems that use waste heat from the engine to generate hot water and perform heating using a heat exchanger from hot water to air, such as a fan coil unit, but in this case, a refrigerant pipe and a hot water pipe must be brought indoors. In addition, there is a problem that the number of man-hours for piping work increases and the system installation work becomes complicated.

There is also a system in which waste heat from the engine is supplied to a heat exchanger on the heat source side of the heat pump, but in this case, there is a problem that the system efficiency of the engine-driven heat pump decreases.

Furthermore, those who use a gas pump to recirculate freon,
There are many types of systems known, but in this case, a gas pump is required, which increases the number of parts in the system, leading to a decrease in system reliability and an increase in cost.

On the other hand, when installing a refrigerant heater that uses engine waste heat upstream of the indoor heat exchanger, there is a limit to the maximum temperature at which the refrigerant, fluorocarbon, can circulate. Conventionally, a refrigerant heater that utilizes waste heat was not installed upstream of the indoor heat exchanger because it decomposed and became useless as a refrigerant. As shown in the invention of No. 55571, there were many cases in which a refrigerant heater using engine waste heat was disposed downstream of the indoor heat exchanger.

[Purpose of the invention]

Therefore, the present invention solves the above-mentioned conventional problems, and
By connecting the waste heat recovery side of the engine and the refrigerant heater through a temperature control valve to prevent overheating of the refrigerant, the refrigerant heater that uses the waste heat is placed upstream of the indoor heat exchanger. The object of the present invention is to provide an engine heat pump device having a heating capacity superior to conventional ones.

[Structure of the invention]

That is, the engine heat pump device of the present invention has a refrigerant connected to the waste heat recovery side of the engine via the temperature control valve on the upstream side during heating of the indoor heat exchanger of the refrigerant circuit of the engine heat pump air conditioning device. It is constructed by installing a heater.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. Figs. 1 and 2 are system diagrams of an engine heat pump device in an embodiment of the present invention, and Fig. 1 shows the heating mode. FIG. 2 shows the cooling mode.

First, there is an engine 1 and a compressor 8 connected to the engine 1 through a shaft coupling 17 at the bottom of the cooling/heating system using the engine heat pump. After the waste heat is absorbed, it is released from the silencer 4.
``Next, the cooling water from the engine 1 and the exhaust gas heat exchanger 6, which is the waste heat recovery side of the exhaust gas, is transferred to the temperature control valve 6.
The refrigerant of this engine heat pump device is introduced into a refrigerant heater 2 that can heat the refrigerant, and after giving the waste heat of the engine 1 to the refrigerant, it is cooled by a radiator 7, and then the water pump 5
The water is then circulated again as cooling water for the engine 1.

Therefore, the refrigerant heater 2 described above is disposed upstream of the indoor heat exchanger 9 provided in the refrigerant circuit of the air-conditioning device during heating.

Next, the flow of the refrigerant in the heating mode of the air conditioning system is shown by the bold line in FIG. After being heated by the waste heat of the engine 1 in the heater 2, the heat is radiated in the indoor heat exchanger 9 in the indoor unit 19, and then the check valve 15
, heat is input to the outdoor heat exchanger 13 via the liquid receiver 11 and the heating expansion valve 12, and is recirculated from the compressor 8 via the refrigerant switching valve 18 and the accumulator 14.

In this case, since the cooling water containing the waste heat of the engine 1 from the exhaust gas heat exchanger 3 is always sent to the refrigerant heater 2 at a constant water temperature by the temperature control valve 6, the outlet temperature of the refrigerant heater 2 is The temperature of the cooling water is kept constant and does not become higher than that of the cooling water, and as a result, the temperature of the refrigerant flowing into the indoor heat exchanger 9 during heating can be made constant, and overheating of the refrigerant can be prevented.

On the other hand, in cooling mode, as shown by the thick line in Figure 2,
The refrigerant radiates heat through the compressor 8, the refrigerant switching valve 18, the outdoor heat exchanger 13, passes through the check valve 15, the liquid receiver 11, the cooling expansion valve 10, absorbs heat in the indoor heat exchanger 9, and reverses the heat. It is introduced into the compressor 8 via the stop valve 15, the refrigerant switching valve 18, and the accumulator 14, and is recirculated, but as described above, it passes through a line that bypasses the refrigerant heater 2, so that the waste heat from the engine 1 is transferred to the refrigerant. Heat reception can be prevented.

Next, FIG. 3 is a Mollier diagram showing the relationship between the pressure and enthalpy of this engine heat pump device in the heating mode shown in FIG. 1, and FIG. 4 is a similar Mollier diagram for the conventional device. , In Fig. 3, the enthalpy from the mouth to the
Figure 4 shows the equivalent amount of heat heated by the waste heat recovered from the engine, and the amount of heat from the heating capacity is shown in terms of the amount of heat generated by the heating capacity. Waste heat can be added to the heating output of the heat pump, increasing heating capacity.

In addition, in FIGS. 1 and 2, 7 is a radiator, but it can also be used as a heater for hot water supply.

〔Effect of the invention〕

Therefore, in the engine heat pump device of the present invention, since the engine recovered waste heat can be added to the heating output of the heat pump, the heating capacity is increased, and the temperature of the refrigerant flowing into the indoor heat exchanger during heating can be kept constant, which is different from the conventional one. Compared to an engine heat pump device, this has the advantage that the temperature change of the hot air blown from the indoor heat exchanger is smaller, and furthermore, overheating of the refrigerant can be prevented.

Further, if the present invention is adopted, the piping work for the system is relatively simple, the reliability of the system is improved, and the cost is relatively low.

[Brief explanation of the drawing]

1 and 2 are system diagrams of an engine heat pump device according to an embodiment of the present invention, in which FIG. 1 shows the heating mode, and FIG. 2 shows the cooling mode.
FIG. 3 is a Mollier diagram of the engine heat pump device in the heating mode of FIG. 1, and FIG. 4 is a similar Mollier diagram of the conventional example. 1...Engine, 2...Refrigerant heater, 3...Exhaust gas heat exchanger, 6...Temperature control valve, 9...Indoor heat exchanger.

Claims (1)

[Claims] A refrigerant heater connected to the waste heat recovery side of the engine via a temperature control valve is disposed on the upstream side of the refrigerant circuit of the engine heat pump air-conditioning system during heating of the indoor heat exchanger. Engine heat pump equipment.