JPH04359756A - Air cooled heat pump type freezer - Google Patents

Abstract

PURPOSE:To improve a capability of hot water operation by utilizing heat of oil of high temperature during a hot water operation and to prevent a reduction of hot water operation through over-cooling of high pressure liquid refrigerant even in the case that an evaporating temperature is reduced due to a reduction in surrounding air temperature. CONSTITUTION:An oil cooler 3 is divided into the first oil cooler 3a and the second oil cooler 3b. The first cooling pipe 15 communicating with a liquid receiving device 6 is connected to the first oil cooler 3a. The second cooling pipe 17 having a valve 14 which is closed during a cold water operation and opened during a hot water operation is connected to the second oil cooler 3b. The second cooling pipe 17 is made to communicate with a cold water pipe 16 for a utilization side heat exchanger 5. An economizer pipe 21 of an intermediate cooler 12 disposed in a high pressure liquid pipe 20 passes through a three-way valve 18 and is sucked into the compressor 1. During a hot water operation, water passing through the second cooling pipe 17 is heat exchanged at the second oil cooler 3b to enable a capability of the hot water operation to be improved. During a hot water operation, since a high pressure liquid refrigerant can be over-cooled with an intermediate cooler 12, a reduction in capability of hot water operation caused by a reduction in the surrounding air temperature can be prevented.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an air-cooled heat pump type refrigeration system, and more specifically, a compressor, an oil recovery device provided on the discharge side of the compressor, a four-way switching valve, an oil cooler, and a user-side water heat exchanger. The present invention relates to an air-cooled heat pump type refrigeration system that includes a liquid receiver, an air heat exchanger on the heat source side, an expansion mechanism for the water heat exchanger on the usage side, and an expansion mechanism for the air heat exchanger on the heat source side, and enables cold water operation and hot water operation.

0002

2. Description of the Related Art Conventionally, a refrigeration system having a refrigeration cycle capable of hot water operation is disclosed in Japanese Patent Application Laid-Open No. 2-287058 and is already known as shown in FIG. In this refrigeration system, an oil recovery device D, a condenser E, a liquid receiver F, an expansion mechanism G, and an evaporator H are sequentially connected to the discharge side of the compressor C, and the refrigerant discharged from the compressor C is connected to the solid line. A refrigeration cycle is configured to circulate as shown by the arrow, and an oil cooler K is interposed in an oil return pipe J that connects the oil recovery device D and the oil supply port I of the compressor C. In the oil cooler K, a branch pipe M branching from a high-pressure liquid pipe S connected to the outlet side of the liquid receiver F is connected to the oil cooler K via an expansion valve Q. The oil is cooled by the refrigerant flowing through the refrigerant cooling pipe L. In addition, in FIG. 2, O is a communication pipe connected to the outlet side of the cooling pipe L in the oil cooler K, and is connected to the intermediate port N of the compressor C. Further, P is an accumulator connected to the suction side of the compressor C, and R is a connecting pipe connecting the gas region of the liquid receiver F to the intermediate port N of the compressor C.

0003

[Problems to be Solved by the Invention] However, in the above-mentioned refrigeration system, when hot water operation is performed in which hot water is taken out by driving the compressor C, the oil cooling is carried out in the oil cooler K from the liquid receiver F. Since heating is performed using a liquid refrigerant, the heating capacity does not decrease, but the heating capacity cannot be improved because the temperature of the oil, which becomes high temperature along with the discharged gas, is not used to generate hot water.

[0004] Therefore, when the outside air temperature decreases and the evaporation temperature decreases, the specific weight of the evaporated refrigerant gas decreases, resulting in a decrease in the amount of refrigerant circulation and a decrease in heating capacity. There is a problem that cannot be compensated for.

On the other hand, the liquid refrigerant used for oil cooling in the oil cooler K is depressurized by the expansion valve Q, exchanges heat with the high-temperature oil, and evaporates, and the evaporated gas refrigerant flows into the connecting pipe O.
The gas refrigerant is sucked into the intermediate port N of the compressor C through the intermediate port N. However, since the gas refrigerant is sucked from the intermediate port N as described above, an intercooler is used to draw the liquid refrigerant into the intermediate port N. It is also impossible to increase the amount of refrigerant circulation by supercooling. That is, an intercooler having an economizer pipe is interposed in the middle of the high-pressure liquid pipe S, and this economizer pipe is connected to an intermediate port (economizer port), so that the liquid refrigerant is supercooled in the intercooler. It is known that an economizer mechanism is incorporated to improve the refrigerating capacity. In this case, the performance of the compressor C makes it impossible to use a configuration in which the economizer pipe is opened to the intermediate port N together with the communication pipe O.

Therefore, when oil cooling is performed using a refrigerant as described above, it is not possible to supercool the liquid refrigerant using the intercooler and improve the refrigerating capacity.

[0007] The present invention is capable of compensating for a decrease in heating capacity even when the outside air temperature decreases by utilizing the temperature of oil that becomes high temperature together with the discharged gas refrigerant to form hot water, and by performing oil cooling with cold water. This invention focused on the ability to use an intercooler, and the first purpose is to improve the performance of hot water operation by effectively utilizing the heat of the oil cooled during hot water operation, and also to improve the ability of hot water operation. Even when the temperature drops and the evaporation temperature drops, it is possible to prevent a drop in hot water operation capacity due to a decrease in the amount of refrigerant circulation.

[0008] The second objective is to achieve the above-mentioned objectives while also improving the ability of chilled water operation by using an intercooler when there is a surplus to cool the oil during chilled water operation. This is the point.

[0009]

[Means for Solving the Problems] In order to achieve the above object, the first invention utilizes a compressor 1, an oil recovery device 2 provided on the discharge side of the compressor 1, a four-way switching valve 4, and an oil cooler 3. Side water heat exchanger 5, liquid receiver 6, heat source side air heat exchange 7, usage side water heat exchanger expansion mechanism 10, and heat source side air heat exchanger expansion mechanism 1
1, the air-cooled heat pump type refrigeration system is capable of cold water operation and hot water operation.
It is divided into an oil cooler 3a and a second oil cooler 3b, and a first cooling pipe 15 communicating with the liquid area of the liquid receiver 6 is connected to the first oil cooler 3a. The cooler 3b has on-off valves 14, 14 that close during cold water operation and open during hot water operation,
A second cooling pipe 17 communicating with cold and hot water pipes 16, 16 to the user-side water heat exchanger 5 is connected, while an economizer port 19 is provided in the compressor 1, and a high-pressure liquid pipe 20 is connected to the compressor 1.
An intercooler 12 having an economizer pipe 21 is interposed therein, and the economizer pipe 21 and the secondary side pipe 22 of the first cooling pipe 15 to the first oil cooler 3a are connected to the economizer port 19. The connection was made alternatively via the switching mechanism 18.

Further, in the second invention, the oil cooler 3 is divided into a first oil cooler 3a and a second oil cooler 3b, and the liquid in the liquid receiver 6 is supplied to the first oil cooler 3a. The first area that communicates with the area
In addition to connecting the cooling pipe 15, the second oil cooler 3b has on-off valves 14, 14 that close during cold water operation and open during hot water operation, and communicate with cold and hot water pipes 16, 16 to the user side water heat exchanger 5. The second cooling pipe 17 is connected to the compressor 1.
An economizer port 19 is provided in the high pressure liquid pipe 2.
An intercooler 12 having an economizer pipe 21 is interposed between the economizer pipe 21 and the first cooling pipe 15.
and the secondary side piping 22 for the first oil cooler 3a,
It is connected to the economizer port 19 through a three-way valve 13 whose opening ratio can be adjusted, and detects the oil cooling capacity of the first oil cooler 3a during cold water operation to cope with excess capacity. Therefore, an opening degree control means is provided for decreasing the opening degree of the first cooling pipe side port b and increasing the opening degree of the economizer piping side port a.

[0011]

[Operation] In the first invention, during hot water operation, the second cooling pipe 1
The on-off valves 14, 14 of No. 7 are opened, and the switching mechanism 18 is switched to connect the economizer pipe 21 and the economizer port 19, and the oil recovery device 2 is opened.
The oil flowing from the oil cooler 3 to the oil cooler 3 is exchanged with the water flowing through the second cooling pipe 17 in the second oil cooler 3b to cool the oil and also heat the water. Hot water can be obtained by effectively utilizing the heat of the oil flowing through 3, and the ability of hot water operation can be improved.

[0012] Also, during hot water operation, the second oil cooler 3b
Since the oil is cooled in the intermediate cooler 12, the economizer piping 21 can be used, and the liquid refrigerant flowing through the high-pressure liquid pipe 20 from the liquid receiver 6 to the heat source side air heat exchanger 7 in the intercooler 12 By supercooling the amount of refrigerant, it is possible to increase the amount of refrigerant circulated. Therefore, even if the outside air becomes low temperature and the evaporation temperature in the heat source side air heat exchanger 7 decreases, the amount of refrigerant circulation can be prevented from decreasing, and the ability of hot water operation can be prevented from decreasing. .

In the second invention, while performing the same effect as the first invention, when there is a surplus in the oil cooling capacity in the first oil cooler 3a during cold water operation, the opening degree control means: Corresponding to the degree of surplus oil cooling capacity in the first oil cooler 3a, the opening degree of the first cooling pipe side port b in the three-way valve 13 decreases, while the opening degree of the first cooling pipe side port b in the three-way valve 13 decreases. The opening degree of port a increases, and the first oil cooler 3a is connected to the first cooling pipe 15.
The intercooler 12 can be used while preventing the flow of excess refrigerant in excess of the amount required to cool the oil. Therefore, during chilled water operation, the liquid refrigerant can be supercooled by using the surplus of oil cooling in the intercooler 12 while oil cooling is performed using the refrigerant, so that the capability of chilled water operation can also be improved.

[0014]

[Example] The air-cooled heat pump type refrigeration system shown in Fig. 1 is
An oil recovery device 2 connected to the discharge side of the compressor 1 and an accumulator 8 connected to the suction side of the compressor 1 are connected to a fixed port of the four-way switching valve 4, while the four-way switching valve 4 is switched. A water heat exchanger 5 on the usage side, a liquid receiver 6, and an air heat exchanger 7 on the heat source side are successively installed between the ports.

[0015] Furthermore, an expansion mechanism 10 for the usage side water heat exchanger consisting of an expansion valve is provided between the usage side water heat exchanger 5 and the liquid receiver 6; An expansion mechanism 11 for the heat source side air heat exchanger consisting of an expansion valve is interposed between the liquid receiver 6 and the refrigerant discharged from the compressor 1 by switching the four-way switching valve 4. A hot water operation in which the water is flowed from the user side water heat exchanger 5 to the heat source side air heat exchanger 7, and conversely, a cold water operation in which it is flowed from the heat source side air heat exchanger 7 to the user side water heat exchanger 5. We are making it possible to do this.

Furthermore, an oil supply pipe 30 interposed with an oil cooler 3 consisting of first and second oil coolers 3a and 3b, which will be described later, is connected to the oil reservoir tank 2a attached to the oil recovery device 2. The oil supplied to the oil supply port 31 provided on the suction side of the compressor 1 is cooled in the oil cooler 3.

In the air-cooled heat pump type refrigeration system constructed as described above, the oil cooler 3 is divided into a first oil cooler 3a and a second oil cooler 3b.
A first cooling pipe 15 communicating with the liquid region of the liquid receiver 6 is connected to the oil cooler 3a, and the second oil cooler 3b has on-off valves 14, 14 that close during cold water operation and open during hot water operation, A second cooling pipe 17 that communicates with cold and hot water pipes 17, 17 to the user-side water heat exchanger 5 is connected, while an economizer port 19 is provided in the compressor 1, and an economizer pipe 21 is connected to the high-pressure liquid pipe 20. The economizer pipe 21 and the secondary pipe 22 of the first cooling pipe 15 to the first oil cooler 3a are connected to the economizer port 19 via the switching mechanism 18 by interposing an intercooler 12 with a It is connected selectively.

In the embodiment shown in FIG.
The outlet 32 of a and the oil supply port 31 of the compressor 1 are connected by the oil supply pipe 30, and the refrigerant in the oil reservoir tank 2a passes through the first and second oil coolers 3a and 3b. This allows the oil to flow into the oil supply port 31.

Furthermore, the first cooling pipe 15 having one end opened into the liquid region of the liquid receiver 6 is connected to the heat transfer tube (not shown) piped to the first oil cooler 3a. The first cooling pipe 15 is equipped with an oil temperature control valve 9 for adjusting the temperature of the oil cooled by the first oil cooler 3a, and a heat transfer tube (not shown) piped to the second oil cooler 3b. , the second cooling pipe 17 connected to the cold and hot water pipes 16, 16 connected to the user-side water heat exchanger 5 is connected, and the second cooling pipe 17 is closed during cold water operation, and On-off valves 14, 14 that open during hot water operation are interposed, and the oil flowing from the oil recovery device 2 is heat exchanged with the water flowing through the second cooling pipe 17 in the second oil cooler 3b only during hot water operation. to get hot water.

Further, the compressor 1 is provided with a pair of economizer ports 19, and the high pressure liquid pipe 20 between the liquid receiver 6 and the heat source side air heat exchanger 7 is provided with a heat transfer pipe (not shown). One end of this heat transfer tube is connected to the economizer pipe 21 which is connected to a three-way valve 13 (to be described later), and the other end of this heat transfer tube is connected to the intermediate cooler 12. A branch pipe 33 that branches from the high-pressure liquid pipe 20 between the cooler 12 and the liquid receiver 6 and is equipped with a flow control valve 38 that adjusts the degree of superheat of the refrigerant gas flowing through the economizer pipe 21 is connected. In the intercooler 12, heat is exchanged between the refrigerant flowing from the branch pipe 33 to the economizer pipe 21 and the high-pressure liquid refrigerant flowing from the liquid receiver 6 to the heat source side air heat exchanger 7 during hot water operation. This allows this high-pressure liquid refrigerant to be supercooled.

Furthermore, a communication pipe 34 communicating with the economizer port 19, the economizer pipe 21, and the secondary side pipe which is the secondary side of the first cooling pipe 15 with respect to the first oil cooler 3a. 22 is connected via the three-way valve 13, and the communication pipe 34 is connected to the fixed port c of the three-way valve 13, while the first cooling port which is one switching port of the three-way valve 13 The secondary side piping 22 is connected to the pipe side port b, and the economizer piping 21 is connected to the economizer piping side port a, which is the other switching port. During hot water operation, the first cooling pipe side port b is connected to the economizer piping 21. is fully closed and the economizer piping side port a is fully open, and during cold water operation, the switching mechanism is configured such that the first cooling pipe side port b is fully open and the economizer piping side port a is fully closed. 18, the refrigerant passes through the economizer pipe 21 during hot water operation, and the refrigerant passes through the first cooling pipe 15 during cold water operation.
The refrigerant passing through is injected into the compressor 1 via the economizer port 19.

Note that 35 is a check valve provided on the suction side of the compressor 1, and 36 and 37 are check valves provided in the expansion mechanisms 10 and 11, respectively.

In the air-cooled heat pump type refrigeration system constructed as described above, when operating hot water, the four-way switching valve 4 is switched to the solid line position to circulate the refrigerant discharged from the compressor 1 in the direction of the solid line arrow. The refrigerant discharged from the compressor 1 exchanges heat with the cold water flowing through the cold/hot water pipe 16 in the user-side water heat exchanger 5, and the refrigerant condenses to become a liquid refrigerant and heats this cold water. to obtain hot water. The liquid refrigerant heated and condensed from this cold water passes through the liquid receiver 6 and the intercooler 12, is depressurized by the heat source side air heat exchanger expansion mechanism 11, and is transferred to the heat source side air heat exchanger. After being evaporated at step 7, it is circulated through the four-way switching valve 4 and back to the accumulator 8.

During such hot water operation, the on-off valves 14, 14 of the second cooling pipe 17 are opened, the three-way valve 13 is switched to the solid line position, and the economizer piping side port a is fully opened to the fixed port c. while the first
Fully close the cooling pipe side port b, and connect the economizer pipe 2.
1 and the economizer port 19 are communicated with each other. Therefore, the oil flowing from the oil recovery device 2 to the oil supply port 31 is cooled by exchanging heat with the cold water flowing through the second cooling pipe 17 in the second oil cooler 3b. The cold water flowing through the second cooling pipe 17 is heated by the oil. Therefore, hot water can be obtained by effectively utilizing the heat of the oil flowing through the second oil cooler 3b, and by dissipating heat to the cold water in the second oil cooler 3b, the capability of hot water operation can be increased. This can be improved compared to the case where only the user-side water heat exchanger 5 is used.

Further, during hot water operation, as described above, the economizer pipe 21 is connected to the communication pipe 34, that is, the economizer port 19 via the three-way valve 13 by switching the three-way valve 13. Therefore, intermediate pressure refrigerant can be injected into the compressor 1 through the economizer port 19 using the economizer piping 21, and therefore the intercooler 12
In this case, the liquid refrigerant flowing through the high-pressure liquid pipe 20 from the liquid receiver 6 to the heat source side air heat exchanger 7 can be supercooled. As a result, the outside air temperature decreases and the evaporation temperature of the refrigerant in the heat source side air heat exchanger 7 decreases,
Even if the specific weight of the gas refrigerant decreases, the amount of refrigerant circulation can be increased, so it is possible to prevent the amount of refrigerant circulation from decreasing. This can prevent the hot water operation ability from decreasing.

Furthermore, when performing cold water operation, the four-way switching valve 4 is switched to the dotted line position to circulate the refrigerant discharged from the compressor 1 in the direction of the dotted line arrow, and the refrigerant is circulated in the direction of the dotted line arrow. The liquid refrigerant condensed by exchanging heat with air passes through the intercooler 12 and the liquid receiver 6,
The refrigerant is depressurized by the expansion mechanism 10 for the user-side water heat exchanger, flows into the user-side water heat exchanger 5, and exchanges heat with the hot water flowing through the cold/hot water pipe 16 in the user-side water heat exchanger 5. It evaporates to become a gas refrigerant and cools this hot water to obtain cold water. Then, the gas refrigerant that has cooled the hot water and evaporated is circulated through the four-way switching valve 4 and back to the accumulator 8.

During such cold water operation, the three-way valve 1
3 to the dotted line position, and by this switching, the economizer piping side port a is fully closed with respect to the fixed port c, while the first cooling pipe side port b is fully opened, and the secondary side piping 22 and It communicates with the economizer port 19. Therefore, the oil flowing from the oil recovery device 2 to the oil supply port 31 is cooled by exchanging heat with the refrigerant flowing through the first cooling pipe 15 in the oil cooler 3a, and the oil is cooled and evaporated. The refrigerant flows from the three-way valve 13 to the economizer port 19.

In the above embodiment, the three-way valve 13 is used, and the economizer piping side port a of the three-way valve 13 is
and the first cooling pipe side port b and alternatively the communication pipe 34.
However, the secondary side piping 22 and the economizer piping 21 are each provided with an on-off valve consisting of, for example, a solenoid valve, so that these on-off valves are selectively opened and closed. You can.

Next, an embodiment of the second invention will be explained. In the embodiment described above, the fixed port c of the three-way valve 13 is selectively opened and closed to one of the ports a and b on the switching side, whereas in the second invention, the three-way valve The opening ratio of the economizer piping side port a and the first cooling pipe side port b of No. 13 to the fixed port c can be adjusted. Note that other than this configuration, this embodiment is basically the same as the embodiment of the first invention shown in FIG. 1, and the differences from the first invention will be explained.

That is, as described above, after making it possible to adjust the opening ratio of the first cooling pipe side port b and the economizer piping side port a of the three-way valve 13 to the fixed port c, as shown in FIG. As described above, the first oil cooler 3a is provided with a cooling capacity detector 40 for detecting the oil cooling capacity of the first oil cooler 3a during cold water operation, and is mainly composed of a controller 41 having a built-in microcomputer. , an opening control means configured by connecting the cooling capacity detector 40 to the input side and the three-way valve 13 to the output side is provided, and during cold water operation, based on the detection of the cooling capacity detector 40, Based on the output of the controller 41, the opening degree of the first cooling pipe side port b is decreased and the opening degree of the economizer piping side port a is increased in response to the surplus oil cooling capacity in the first oil cooler 3a. It is configured to do so.

[0031] With the above configuration, while obtaining the same effect as the embodiment of the first invention described above, when there is a surplus in the oil cooling capacity in the first oil cooler 3a during cold water operation, the cooling Upon detection of surplus oil cooling capacity by the capacity detector 40, the controller 41 outputs an output to increase the amount of water in the three-way valve 13 corresponding to the degree of surplus oil cooling capacity in the first oil cooler 3a. While the opening degree of the first cooling pipe side port b decreases, the opening degree of the economizer piping side port a of the three-way valve 13 increases, and the first cooling pipe 15 is filled with oil in the first oil cooler 3a. The intercooler 12 can be used by preventing excess refrigerant in excess of the amount required for cooling from flowing. Therefore, during cold water operation, the liquid refrigerant can be supercooled using the intercooler 12, so that the ability of cold water operation can be improved.

[0032]

As explained above, in the first aspect of the present invention, the compressor 1, the oil recovery device 2 provided on the discharge side of the compressor 1, the four-way switching valve 4, the oil cooler 3, and the use side Equipped with a water heat exchanger 5, a liquid receiver 6, a heat source side air heat exchanger 7, a usage side water heat exchanger expansion mechanism 10, and a heat source side air heat exchanger expansion mechanism 11, enabling cold water operation and hot water operation. In the air-cooled heat pump type refrigeration system, the oil cooler 3 is divided into a first oil cooler 3a and a second oil cooler 3b, and the liquid area of the liquid receiver 6 and the liquid area of the liquid receiver 6 are connected to the first oil cooler 3a. Communicating first cooling pipe 1
5, and the second oil cooler 3b has on-off valves 14, 14 that close during cold water operation and open during hot water operation, and communicate with cold and hot water pipes 16, 16 to the user side water heat exchanger 5. 2 cooling pipes 17 are connected, while an economizer port 19 is provided in the compressor 1, and an intercooler 12 having an economizer pipe 21 is interposed in the high-pressure liquid pipe 20, so that the economizer pipe 21 and the first cooling pipe are connected to each other. Since the secondary side piping 22 of the pipe 15 to the first oil cooler 3a is selectively connected to the economizer port 19 via the switching mechanism 18, during hot water operation, the second cooling pipe 17, the on-off valves 14, 14 open, and the switching mechanism 18
By switching the economizer piping 21 and the economizer port 19, the oil flowing from the oil recovery device 2 to the oil cooler 3 is changed to the cold water flowing through the second cooling pipe 17 in the second oil cooler 3b. The oil can be cooled and the cold water can be heated by exchanging heat with the oil. Therefore, hot water can be obtained by effectively utilizing the heat of the high-temperature oil flowing through the oil cooler 3, and compared to the case where hot water is obtained only by the user-side water heat exchanger 5, hot water operation is improved. ability can be improved.

[0033] Also, during hot water operation, the second oil cooler 3b
Since the oil is cooled in the intermediate cooler 12, the economizer piping 21 can be used, and the liquid refrigerant flowing through the high-pressure liquid pipe 20 from the liquid receiver 6 to the heat source side air heat exchanger 7 in the intercooler 12 It is possible to perform supercooling and increase the amount of refrigerant circulation. Therefore, even if the outside air becomes low temperature and the evaporation temperature in the heat source side air heat exchanger 7 decreases, the amount of refrigerant circulation can be prevented from decreasing, and together with the heating of the cold water by the oil, Even when the outside air temperature decreases, it is possible to prevent the hot water operation ability from decreasing.

In the second invention, in place of the switching mechanism 18 in the first invention, a three-way valve 13 whose opening ratio can be adjusted is provided.
using the economizer pipe 21 and the first cooling pipe 1.
The secondary side piping 22 for the first oil cooler 3a of No. 5 is connected to the economizer port 19 via the three-way valve 13.
and, during cold water operation, detects the oil cooling capacity of the first oil cooler 3a, reduces the opening degree of the first cooling pipe side port b in response to excess capacity, and Since the opening degree control means for increasing the opening degree of port a is provided, while obtaining the same effect as the above-mentioned first invention, when a surplus occurs in the oil cooling capacity in the first oil cooler 3a during cold water operation. , the opening degree control means reduces the opening degree of the first cooling pipe side port b of the three-way valve 13 in accordance with the degree of excess oil cooling capacity in the first oil cooler 3a; The degree of opening of the economizer piping side port a in the valve 13 is increased, and the excess refrigerant in excess of the amount required to cool the oil in the first oil cooler 3a flows into the first cooling pipe 15. Therefore, the intercooler 12 can be used. Therefore, during cold water operation, the intercooler 12 can be used to supercool the liquid refrigerant, thereby improving the ability of cold water operation.

[Brief explanation of the drawing]

FIG. 1 is a piping system diagram of an air-cooled heat pump type refrigeration apparatus of the present invention.

FIG. 2 is a piping system diagram showing a conventional example.

[Explanation of symbols]

1 Compressor 2 Oil recovery device 3 Oil cooler 3a First oil cooler 3b Second oil cooler 4 Four-way switching valve 5 User side water heat exchanger 6 Liquid receiver 7 Heat source side air heat exchanger 10 User side water Expansion mechanism 11 for heat exchanger
Heat source side air heat exchanger expansion mechanism 12 Intercooler 13 Three-way valve 14 Open/close valve 15 First cooling pipe 16 Cold/hot water pipe 17 Second cooling pipe 19 Economizer port 20 High pressure liquid pipe 21 Economizer pipe 22 Secondary side pipe a...Economizer Piping side port b...First cooling pipe side port

Claims (2)

[Claims] Claim 1: A compressor 1, an oil recovery device 2 provided on the discharge side of the compressor 1, a four-way switching valve 4, an oil cooler 3, a water heat exchanger 5 on the user side, a liquid receiver 6, and air on the heat source side. In an air-cooled heat pump type refrigeration system that includes a heat exchanger 7, an expansion mechanism 10 for a water heat exchanger on the user side, and an expansion mechanism 11 for an air heat exchanger on the heat source side, and enables cold water operation and hot water operation, the oil cooler 3 is It is divided into a first oil cooler 3a and a second oil cooler 3b, and a first cooling pipe 15 communicating with the liquid area of the liquid receiver 6 is connected to the first oil cooler 3a. 2 oil cooler 3b
It has on-off valves 14, 14 that close during cold water operation and open during hot water operation, and connects cold and hot water pipes 16, 16 to the water heat exchanger 5 on the user side.
At the same time, an economizer port 19 is provided in the compressor 1, and an intercooler 12 having an economizer pipe 21 is interposed in the high pressure liquid pipe 20, so that the economizer pipe 21 and the economizer pipe 21 are connected to each other. Said first cooling pipe 1
An air-cooled heat pump type refrigeration system characterized in that a secondary side pipe 22 for the first oil cooler 3a of No. 5 is selectively connected to the economizer port 19 via a switching mechanism 18. 2. A compressor 1, an oil recovery device 2 provided on the discharge side of the compressor 1, a four-way switching valve 4, an oil cooler 3, a water heat exchanger 5 on the user side, a liquid receiver 6, and air on the heat source side. In an air-cooled heat pump type refrigeration system that includes a heat exchanger 7, an expansion mechanism 10 for a water heat exchanger on the user side, and an expansion mechanism 11 for an air heat exchanger on the heat source side, and enables cold water operation and hot water operation, the oil cooler 3 is It is divided into a first oil cooler 3a and a second oil cooler 3b, and a first cooling pipe 15 communicating with the liquid area of the liquid receiver 6 is connected to the first oil cooler 3a. 2 oil cooler 3b
It has on-off valves 14, 14 that close during cold water operation and open during hot water operation, and connects cold and hot water pipes 16, 16 to the water heat exchanger 5 on the user side.
At the same time, an economizer port 19 is provided in the compressor 1, and an intercooler 12 having an economizer pipe 21 is interposed in the high-pressure liquid pipe 20, so that the economizer pipe 21 and Said first cooling pipe 1
The secondary side piping 22 for the first oil cooler 3a of No. 5 is connected to the economizer port 19 via a three-way valve 13 whose opening ratio can be adjusted, and during cold water operation, the first oil An opening control means is provided for detecting the oil cooling capacity of the cooler 3a, and reducing the opening degree of the first cooling pipe side port b and increasing the opening degree of the economizer piping side port a in response to the excess capacity. An air-cooled heat pump type refrigeration system characterized by: