JPH0332712B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an engine drive system that drives a compressor using an internal combustion engine that uses natural gas, oil, etc. as a heat source to perform heat pump cooling/heating operation or heat pump hot water heating. The present invention relates to a heat pump device.

Configuration of a conventional example and its problems FIG. 2 shows a configuration diagram of a conventional engine-driven heat pump device. In the figure, 1' is an engine having an exhaust gas heat exchanger 2', 3' is an exhaust gas discharge muffler, 4' is a starter that starts the engine 1', 5' is a compressor driven by the engine 1', and 6 ' is a four-way valve, 7a' is an outdoor fan, 7b' is an outdoor heat exchanger, 8' is a pressure reducer, 9b' is an indoor heat exchanger, and 9a' is an indoor fan. These are connected in sequence to form the cooling/heating heat pump circuit A. ', the refrigerant circuit is branched from this cooling/heating heat pump circuit A' via a solenoid valve 17a', and has a heater 13' that exchanges heat with the fluid 12' in the heat storage tank 11' using the condensation heat of the refrigerant. It constitutes a heat pump hot water supply circuit B'. The engine 1' circulates cooling water through the exhaust gas heat exchanger 2' with a pump 19', recovers exhaust heat, and heats it by exchanging heat with the fluid 12' in the heat storage tank 11'. This constitutes an exhaust heat recovery circuit C' having 15b' is a radiator, and a dedicated fan 15
a', and in this exhaust heat recovery circuit C', the circuit is inserted in series between the heat exhaust device 14' and the engine 1' on the downstream side of the heat exhaust device 14' via a three-way solenoid valve 16'. ing. This is to prevent the engine 1' from overheating; the temperature of the fluid 12' increases to the extent that it does not exchange heat with the fluid in the heat storage tank 14', and the temperature of the cooling water that should cool the engine 1' increases. When the engine rises, the three-way water valve 16' is switched to flow the cooling medium to the radiator 15b', thereby radiating the exhaust heat recovered from the engine 1' and the exhaust gas heat exchanger 2' to the atmosphere.

When such a conventional engine-driven heat pump device performs heating operation, the refrigerant circuit and the exhaust heat recovery circuit are separate, so engine exhaust heat is only stored in the heat storage tank and does not contribute to heating. Therefore, the efficiency of the refrigerant circuit during heating is low. Furthermore, when the temperature of the cooling water exceeds a certain level, the radiator 15b' and dedicated fan 15a' operate to dissipate engine exhaust heat, but with this configuration, the radiator and dedicated fan are required separately, resulting in an increase in the number of parts. This resulted in increased costs. As described above, conventional devices have had the various drawbacks mentioned above.

OBJECTS OF THE INVENTION The present invention obviates the above-mentioned conventional drawbacks.
A refrigerant heater is installed in the exhaust heat recovery circuit, and a liquid pump is installed in the cooling/heating heat pump circuit and connected to the refrigerant heater to form a refrigerant heating circuit that returns refrigerant to the compressor discharge side. When the cooling water reaches a certain temperature during cooling operation, the liquid pump is activated to dissipate the engine heat from the outdoor heat exchanger, which improves the efficiency of the refrigerant circuit. This is an attempt to remove the .

Structure of the Invention In order to achieve the above object, the present invention sequentially connects an engine, a compressor driven by the engine, a four-way valve, an outdoor heat exchanger, a pressure reducer, an indoor heat exchanger, and a condensate reservoir. a heat pump hot water supply circuit having a heater that is branched from the cooling/heating heat pump circuit via a solenoid valve and heats the fluid in the heat storage tank with the condensation heat of the refrigerant; an exhaust heat recovery circuit having a heat exhaust device that circulates the water using a pump to recover exhaust heat and exchanges heat with the fluid in the heat storage tank; A liquid pump and a refrigerant heater are provided on the downstream side of the condensate liquid reservoir in the cooling/heating heat pump circuit, and a refrigerant heater is provided on the downstream side of the condensate liquid reservoir, and a refrigerant heater is provided to give exhaust heat to the refrigerant side. A refrigerant heating circuit is provided that communicates with the discharge side of the compressor, and the liquid pump is operated during heating operation to not only utilize the engine exhaust heat for heating, but also to raise the cooling water to a predetermined temperature or higher during cooling operation. A function is provided for radiating excess engine exhaust heat from the outdoor heat exchanger by operating a liquid pump when the temperature is low. As a result, the efficiency of the refrigerant circuit during heating operation is improved, and a radiator and dedicated fan to dissipate excess engine heat are no longer required, resulting in cost reduction due to a reduction in the number of parts.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

In the figure, 1 is an engine having an exhaust gas heat exchanger 2, 3 is an exhaust gas discharge muffler, 4 is a starter that starts the engine 1, 5 is a compressor driven by the engine 1, 6 is a four-way valve, and 7a is an outdoor Fan, 7b is an outdoor heat exchanger, 8a is an indoor fan,
8b is an indoor heat exchanger, 9 is a condensate liquid reservoir, 12
1 is a pressure reducer for heating, 11 is a pressure reducer for cooling, 13a is a solenoid valve for heating time, 14 is a solenoid valve open for cooling, 1
3b is a check valve that can be passed during cooling, and 15 is a check valve that can be passed during heating.These are connected in sequence to form a cooling/heating heat pump circuit A. The refrigerant circuit is branched through the solenoid valve 16a of the heat storage tank 24.
A heat pump hot water supply circuit B includes a heater 17 that exchanges heat with the fluid 25 inside using the condensation heat of the refrigerant. Here, 18 is a pressure reducer during heat pump hot water supply operation, and 19 and 16b are check valves that fix the flow direction of the refrigerant, respectively. A pump 23 pumps cooling water to the engine 1 and the exhaust gas heat exchanger 2.
An exhaust heat recovery circuit C includes a heat exhaust device 22 that circulates and recovers exhaust heat and heats it by exchanging heat with the fluid 25 in the heat storage tank 24. In this heat exhaust circuit, a refrigerant heater 20 that gives exhaust heat to the refrigerant side is provided upstream of the heat exhaust device 22, and in the cooling/heating heat pump circuit, a liquid pump is provided downstream of the condensate liquid reservoir 9. A refrigerant heater 2 is provided on the downstream side of the refrigerant heater 10.
A refrigerant heating circuit that communicates with the discharge side of the compressor 5 via the check valve 21 is provided.

In the above configuration, the operation is explained as follows.
During heat pump operation, first the engine 1 is started by the starter 4 to drive the compressor 5, and the four-way valve 6 is switched according to the cooling/heating hot water supply operation, and the refrigerant (not shown) is turned on by the arrow in the cooling/heating heat pump circuit A during cooling. By flowing as shown by the solid line, the outdoor heat exchanger 7b acts as a condenser, and the indoor heat exchanger 8b acts as an evaporator. The refrigerant exiting the outdoor heat exchanger 7b passes through the solenoid valve 14.
A portion of the condensed liquid accumulates in the liquid reservoir 9, but then passes through the cooling pressure reducer 11 to the indoor heat exchanger 8b.
The air flows through the check valve 13b and finally returns to the compressor 1.

During heating operation, on the other hand, the refrigerant flows as indicated by the dotted arrow to make the outdoor heat exchanger 7b act as an evaporator, and the indoor heat exchanger 8b acts as a condenser, passing through the solenoid valve 13a and flowing out of the indoor heat exchanger 8b. The refrigerant is checked by check valve 1.
5 and some of the condensate accumulates in the liquid reservoir 9,
Next, it passes through the heating pressure reducer 12 to the outdoor heat exchanger 7.
It flows into b.

In addition, during heat pump hot water supply operation, the four-way valve 6 is switched to the heating side, as shown by the dashed line, and the refrigerant passes through the solenoid valve 16a, condenses in the heater 17 in the heat storage tank 24, and flows. , and is evaporated in the outdoor heat exchanger 7b via the hot water supply pressure reducer 18. Since the engine 1 is operated in both the cooling/heating heat pump operation and the heat pump hot water supply operation, by using the exhaust heat recovery circuit C at the same time, cooling water (not shown in the figure) is supplied to the engine 1 and the exhaust gas heat exchanger 2 by the pump 23. ) is passed through the refrigerant heater 20 to collect the exhaust heat, and then to the heat storage tank 2 in the heat exhauster 22 via the refrigerant heater 20.
The fluid 25 in 4 is heated.

When the liquid pump 10 is operated during heat pump heating operation, the condensed liquid accumulated in the liquid reservoir 9 flows into the refrigerant heating circuit, and the refrigerant recovers engine exhaust heat in the refrigerant heater 20, and the refrigerant becomes a high-pressure gas. is returned to the discharge side of the compressor 5 via the check valve 21.
The refrigerant is mixed with the refrigerant discharged from the compressor 5 and flows to the indoor heat exchanger 8b, and the engine exhaust heat is applied to the heating via the refrigerant, so that the efficiency of the refrigerant circuit during heating operation is improved.

Furthermore, in general, the temperature of the fluid 25 that can be heated by the heater 17 of the heat pump hot water supply circuit B is about 55°C due to the refrigerant pressure conditions, but the temperature of the fluid 25 obtained by the exhaust heat generator 22 in the exhaust heat recovery circuit C is 85
~90℃. The fluid 25 heated by the heater 17 is further heated by the heat exhauster 22. During cooling operation, when the temperature of the fluid 25 in the heat storage tank 24 rises in the exhaust heat recovery circuit C, the cooling water is removed from the fluid 25 in the heat exhaust device 22.
It becomes difficult to exchange heat, and the temperature of the cooling water at the inlet of the heat exhaust device 22 increases. When the temperature of the cooling water returning to the engine 1 exceeds a certain set value, the liquid pump 10 is operated to send the condensed liquid, and the refrigerant heater 20 vaporizes the condensed liquid using the engine exhaust heat to convert the high-pressure gaseous refrigerant into is mixed with the discharge gas of the compressor 5 and discarded as condensation heat in the outdoor heat exchanger 7b.

In this way, by using the outdoor heat exchanger 7b to dissipate excess heat from the engine, a radiator and a dedicated fan are no longer necessary, and costs can be reduced by reducing the number of parts. In other words, the refrigerant heating circuit
This is intended to be used not only to improve refrigerant circuit efficiency during heating operation, but also to radiate excess engine surplus heat during cooling operation.

Effects of the Invention As described above, the present invention provides a cooling heat pump that sequentially connects an engine, a compressor driven by the engine, a four-way valve, an outdoor heat exchanger, a pressure reducer, an indoor heat exchanger, and a condensate reservoir. a heat pump hot water supply circuit having a heater that is branched from the cooling/heating heat pump circuit via a solenoid valve and heats the fluid in the heat storage tank with the condensation heat of the refrigerant; and circulating cold water by a pump to the exhaust gas heat exchanger of the engine. a heat exhaust circuit having a heat exhaust device for recovering exhaust heat and exchanging heat with the fluid in the heat storage tank; A refrigerant heater is provided to give exhaust heat to the cooling/heating heat pump circuit, and the cooling/heating heat pump circuit is connected to the discharge side of the compressor via a liquid pump and a refrigerant heater downstream of the condensate liquid reservoir and a check valve. A refrigerant heating circuit is provided, and during heating operation, the liquid pump is operated to send condensate from the condensate liquid reservoir to the refrigerant heater, and engine exhaust heat is recovered on the refrigerant side and used for heating. Energy savings can be achieved by improving efficiency.

Furthermore, when the cooling water reaches a predetermined temperature or higher during cooling operation, the liquid pump is activated to recover excess engine exhaust heat on the refrigerant side as described above and radiate the heat in the outdoor heat exchanger. This has various effects, such as eliminating the need for a fan and reducing costs by reducing the number of parts.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of an engine-driven heat pump device of the present invention, and FIG. 2 is a circuit diagram of a conventional engine-driven heat pump device. 1... Engine, 5... Compressor, 6... Four-way valve, 7a
... Outdoor fan, 7b... Outdoor heat exchanger, 8a... Indoor fan, 8b... Indoor heat exchanger, 9... Condensate liquid reservoir, 11... Cooling pressure reducer, 12... Heating pressure reducer,
18... Heat pump water supply pressure reducer, 10... Liquid pump, 17... Heater, 22... Exhaust heat device, 20... Refrigerant heater, 24... Heat storage tank, A... Cooling/heating heat pump circuit, B... Heat pump hot water supply circuit, C... Exhaust Heat recovery circuit.

Claims (1)

[Claims] 1. An engine, a cooling/heating heat pump circuit that sequentially connects a compressor driven by the engine, a four-way valve, an outdoor heat exchanger, a pressure reducer, an indoor heat exchanger, and a condensate liquid reservoir, and a solenoid valve from the cooling/heating heat pump circuit. A heat pump hot water supply circuit has a heater that is branched through the heat storage tank and heats the fluid in the heat storage tank using the condensation heat of the refrigerant, and a heat pump hot water supply circuit that circulates cooling water to the exhaust gas heat exchanger of the engine using a pump to recover exhaust heat and exhaust heat. A heat exhaust circuit having a heat exhauster that exchanges heat with the fluid in the heat storage tank is provided, and a refrigerant heater that provides exhaust heat to the refrigerant side is provided upstream of the heat exhauster in the heat exhaust circuit. provided, in the cooling/heating heat pump circuit, a refrigerant heating circuit is provided downstream of the condensate liquid reservoir, the refrigerant heating circuit is connected to the discharge side of the compressor via a liquid pump, a refrigerant heater, and a check valve; Further, during heating operation, the liquid pump is operated to utilize the engine exhaust heat for heating, and during cooling operation, when the cooling water reaches a predetermined temperature or higher, the liquid pump is operated to transfer excess heat from the engine to the An engine-driven heat pump device equipped with a means to radiate heat from an outdoor heat exchanger.