JP6414791B2 - refrigerator - Google Patents

Description

  The present invention relates to a refrigerator.

  Conventionally, in a refrigeration circuit in which a cooler such as a showcase installed in a supermarket and a refrigerator installed outdoors are connected by a refrigerant pipe, between the condenser and the cooler stored in the refrigerator. A technique is known that includes an economizer that further cools the refrigerant pipe with a refrigerant that flows from the refrigerant pipe and flows back to the injection port of the compressor (for example, see Patent Document 1). According to the configuration of Patent Document 1, the refrigerant pipe can be cooled by an economizer to improve the cooling capacity of the refrigeration circuit, and the compressor can be cooled by the refrigerant returning to the injection port.

JP 2010-7975 A

By the way, in the refrigeration circuit provided with the economizer as described above, the temperature of the refrigerant pipe downstream of the economizer is lower than that of the conventional one, so that condensation is likely to occur in the refrigerant pipe on the cooler side. In the installation facility of a refrigeration circuit such as a supermarket, when the entire refrigeration circuit is provided by new installation or replacement, it is possible to prevent condensation on the refrigerant pipe on the cooler side by performing heat insulation treatment on a necessary part of the refrigerant pipe. On the other hand, when only the refrigerator is replaced without replacing the entire refrigeration circuit, and the refrigeration circuit is configured using the existing refrigerant piping on the cooler side, the refrigerant piping is installed due to restrictions on installation space and installation work. It may be difficult to perform heat insulation, and it may be difficult to effectively prevent condensation on the refrigerant piping on the cooler side. That is, according to the installation state on the cooler side, it becomes a problem to prevent condensation of the refrigerant pipe with a simple configuration.
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a refrigerator capable of preventing condensation of refrigerant piping with a simple configuration according to the installation state on the cooler side. To do.

In order to achieve the above object, the present invention includes a compressor and a condenser, wherein the refrigerant pipe on the upstream side of the compressor and the refrigerant pipe on the downstream side of the condenser are connected to a cooler. An economizer provided in a refrigerant pipe on the downstream side of the condenser, and a cooling injection port for the compressor by branching from the refrigerant pipe downstream of the economizer and exchanging heat with the refrigerant flowing out of the condenser flowing through the economizer A bypass pipe connected to the economizer upstream of the branch pipe and a downstream pipe of the branch pipe, an economizer flow opening / closing valve for opening and closing a flow path through which the refrigerant passes through the economizer, and the bypass pipe a bypass flow channel opening and closing valve for opening and closing the flow path, Rise for expanding the refrigerant on the upstream side of the economizer and the bypass pipe a middle portion of the branch pipe Characterized by comprising a valve, a

Further, the present invention, when opening the economizer flow path on-off valve than if you open the bypass flow channel opening and closing valve, characterized in that the opening degree of the expansion valve is increased control.

  ADVANTAGE OF THE INVENTION According to this invention, the refrigerator which can prevent dew condensation of refrigerant | coolant piping with a simple structure according to the installation state by the side of a cooler can be provided.

It is a schematic diagram of the refrigerating circuit provided with the refrigerator which concerns on embodiment of this invention. It is a schematic diagram of the state which newly established the whole freezing circuit.

Hereinafter, a refrigeration circuit according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram of a refrigeration circuit including a refrigerator according to an embodiment of the present invention.
The refrigeration circuit 10 is provided to cool the inside of a showcase displaying beverages and refrigerated goods in a refrigerated state. The refrigeration circuit 10 is provided in a facility such as a convenience store or a supermarket, for example, and the showcase is installed on the floor in the store.

The refrigeration circuit 10 includes a cooler 11 and a refrigerator 12 disposed in a machine room or the like that is a place different from the room in which the cooler 11 is installed. The refrigeration circuit 10 includes a control unit (not shown) that controls the operations of the refrigerator 12 and the cooler 11.
The refrigeration circuit 10 includes a compressor 13, an oil separator 14, a condenser 15, a receiver tank 16, a supercooler 17, an economizer 18, an expansion valve 19, an evaporator 20, and an accumulator 21 in order. The refrigerant pipe 22 is connected in a ring shape.
The cooler 11 includes a showcase 40 and a refrigerant pipe 22. The showcase 40 includes a case main body (not shown), the expansion valve 19 and the evaporator 20.
The refrigerator 12 includes a compressor 13, an oil separator 14, a condenser 15, a receiver tank 16, a supercooler 17, an economizer 18, an accumulator 21, and a refrigerant pipe 22.

The oil separator 14 separates the oil in the refrigerant and returns it to the compressor 13. The receiver tank 16 stores excess refrigerant. The economizer 18 cools the refrigerant that flows through the economizer 18 to the evaporator 20 side.
The condenser 15 includes a blower fan 15a that cools the refrigerant. The supercooler 17 is an air-cooled heat exchanger provided integrally with the condenser 15, and heat exchange is promoted by blowing air from the blower fan 15 a.
The evaporator 20 includes a blower fan 20a, and heat exchange between the evaporator 20 and air is promoted by the blower of the blower fan 20a, and the inside of the showcase 40 is cooled.

The refrigerant pipe 22 includes a liquid refrigerant pipe 26 that connects the outlet of the condenser 15 and the inlet of the evaporator 20, and a gas refrigerant pipe 27 that connects the outlet of the evaporator 20 and the inlet of the condenser 15. A part of the liquid refrigerant pipe 26 constitutes a refrigerant pipe on the downstream side of the condenser 15 connected to the cooler 11. A part of the gas refrigerant pipe 27 constitutes a refrigerant pipe on the upstream side of the compressor 13.
Specifically, the liquid refrigerant pipe 26 includes a high-pressure liquid pipe 26 a that connects the outlet of the condenser 15 and the expansion valve 19 of the cooler 11, and a low-pressure liquid pipe 26 b that connects the expansion valve 19 and the inlet of the evaporator 20. Prepare. The gas refrigerant pipe 27 includes a low-pressure gas pipe 27 a that connects the outlet of the evaporator 20 and the suction port of the compressor 13, and a high-pressure gas pipe 27 b that connects the discharge port of the compressor 13 and the inlet of the condenser 15. Prepare.

  The high-temperature and high-pressure gas refrigerant compressed by the compressor 13 flows to the high-pressure gas pipe 27b, reaches the condenser 15 through the oil separator 14, and is condensed by the condenser 15 to become a high-pressure liquid refrigerant. The high-pressure liquid refrigerant flows into the high-pressure liquid pipe 26 a, reaches the expansion valve 19 through the receiver tank 16, the supercooler 17, and the economizer 18, and is reduced in pressure when passing through the expansion valve 19 to become a low-pressure liquid refrigerant. . The low-pressure liquid refrigerant after passing through the expansion valve 19 reaches the evaporator 20 through the low-pressure liquid pipe 26b, evaporates in the evaporator 20 to become a low-pressure gas refrigerant, and passes through the low-pressure gas pipe 27a. Return to. In the present embodiment, since the refrigerant is cooled by the supercooler 17 and the economizer 18, the degree of supercooling of the refrigerant can be increased, and the cooling capacity of the cooler 11 can be improved.

The refrigeration circuit 10 bypasses the branch pipe 30 branched from the high-pressure liquid pipe 26 a and connected to the cooling injection port 13 a of the compressor 13, and the economizer 18 provided on the branch pipe 30, upstream of the branch pipe 30. And a bypass pipe 31 connecting the downstream portion and the downstream portion.
The branch pipe 30 branches from the position between the supercooler 17 and the economizer 18 in the high-pressure liquid pipe 26 a, and is connected to the economizer 18 inlet 18 a in the flow path of the branch pipe 30, and the economizer 18. And an injection port connecting pipe 33 for connecting the cooling outlet port 18b and the cooling injection port 13a.

  The economizer connection pipe 32 has a service valve 34 that can open and close the flow path of the branch pipe 30 on one end side, and an electric branch pipe expansion valve 35 (expansion means) on the other end side near the economizer 18. . The economizer connection pipe 32 includes an economizer flow path opening / closing valve 36 that opens and closes the flow path of the economizer connection pipe 32 downstream of the branch pipe expansion valve 35 and upstream of the economizer 18.

  The economizer 18 includes a cooling pipe 18c that allows the refrigerant flowing from the inlet 18a to pass through the outlet 18b. Further, the economizer 18 includes a pipe 18d that constitutes a part of the high-pressure liquid pipe 26a. The cooling pipe 18c is provided close to the pipe 18d so that heat can be efficiently exchanged with the pipe 18d. For example, the cooling pipe 18c and the pipe 18d are provided in a double pipe structure. Further, the economizer 18 is provided so that the refrigerant flowing through the cooling pipe 18c is opposed to the refrigerant flowing through the pipe 18d. For this reason, the refrigerant in the cooling pipe 18c can be efficiently cooled.

One end of the bypass pipe 31 is connected downstream of the branch pipe expansion valve 35 in the economizer connection pipe 32 and upstream of the economizer flow path opening / closing valve 36, and the other end is connected in the middle of the injection port connection pipe 33. The bypass pipe 31 includes a bypass pipe passage opening / closing valve 37 that opens and closes the passage of the bypass pipe 31.
In the present embodiment, the flow of the refrigerant flowing into the branch pipe 30 to the economizer 18 and the flow of the bypass pipe 31 by switching the open / closed state of the bypass pipe flow opening / closing valve 37 and the economizer flow opening / closing valve 36. It can be selected to flow to either of the roads.

  Specifically, in a state where the bypass pipe flow path opening / closing valve 37 is closed and the economizer flow path opening / closing valve 36 is opened (hereinafter, this state is referred to as “economizer use state”), the high pressure liquid pipe 26a is connected to the branch pipe 30 side. The refrigerant that has branched into the economizer connection pipe 32 expands through the branch pipe expansion valve 35 and decreases in temperature, and then passes through the economizer 18 and through the injection port connection pipe 33 to be the cooling injection port 13a. Flow into. In this case, the refrigerant passing through the pipe 18d can be cooled by the refrigerant passing through the cooling pipe 18c to improve the cooling capacity of the evaporator 20, and the compressor 13 can be cooled by the refrigerant flowing through the cooling injection port 13a. However, since the refrigerant greatly cooled by the economizer 18 passes through the high-pressure liquid pipe 26a, the temperature of the high-pressure liquid pipe 26a is lowered, and condensation is likely to occur on the surface of the high-pressure liquid pipe 26a on the downstream side of the economizer 18. When condensation occurs, the condensation falls and causes a problem such as contamination of the installation facility, which causes a problem.

On the other hand, in a state where the bypass pipe passage opening / closing valve 37 is opened and the economizer passage opening / closing valve 36 is closed (hereinafter, this state is referred to as a “bypass state”), the high pressure liquid pipe 26a branches to the branch pipe 30 side. Then, the refrigerant flowing into the economizer connection pipe 32 expands through the branch pipe expansion valve 35 and decreases in temperature, and then flows through the bypass pipe 31 into the injection port connection pipe 33 and into the cooling injection port 13a. To do. In this case, since the refrigerant passing through the pipe 18d is not cooled by the economizer 18, the cooling capacity of the evaporator 20 does not increase, but the temperature of the high-pressure liquid pipe 26a is not so low, and condensation occurs on the surface of the high-pressure liquid pipe 26a. hard. Further, the compressor 13 is effectively cooled by the refrigerant flowing through the cooling injection port 13a. Since the economizer flow path opening / closing valve 36 is upstream of the economizer 18, the refrigerant passing through the branch pipe 30 does not flow into the economizer 18 in the “bypass state”.
Switching between the “bypass state” and the “economizer use state” is performed manually by an operator when the refrigerator 12 is installed, for example, but this switching may be performed by an electromagnetic valve controlled by the control unit.

When the refrigerator 12 is installed in an installation facility such as a store, the entire refrigeration circuit 10 including the refrigerator 12, the cooler 11, and the refrigerant pipe 22 may be newly installed.
When the refrigerator 12 is installed in an installation facility such as a store, only the refrigerator 12 including the refrigerant pipe on the refrigerator 12 side is replaced with an old one to replace the refrigerant pipe 22 on the cooler 11 side. The included cooler 11 may be used as it is. Here, the refrigerant pipe on the cooler 11 side that is used again without being replaced is referred to as an existing pipe 41.

FIG. 1 shows a state where only the refrigerator 12 including the refrigerant pipe 22 on the refrigerator 12 side is replaced with a new one, and the existing cooler 11 including the refrigerant pipe 22 on the cooler 11 side is used. Yes. In FIG. 1, the existing pipe 41 is all the refrigerant pipes in the cooler 11.
The refrigerator 12 in FIG. 1 is provided corresponding to a conventional refrigerator that does not include an economizer, and the temperature of the existing pipe 41 is not so low. Is not given. That is, the existing pipe 41 is a pipe that is likely to cause dew condensation when used at a lower temperature. Here, as the heat insulation treatment, a heat insulating material wound around the outer peripheral surface of the existing pipe 41 is exemplified.

It is conceivable to provide a heat insulating material in the existing pipe 41 in correspondence with the new refrigerator 12 equipped with the economizer 18. However, since the existing piping 41 is provided in places such as the back of the ceiling of a store or the like, in a wall, or under the floor, it is difficult to provide a heat insulating material in addition to the existing piping 41. It is difficult because of problems such as arrangement space and cost.
For this reason, in the configuration of FIG. 1, the refrigerator 12 is used in a “bypass state”. By setting the “bypass state”, the refrigerant flowing to the existing pipe 41 side does not become so low in temperature, so that the new refrigerator 12 equipped with the economizer 18 is connected to the existing pipe 41 that is not provided with a heat insulating material. Moreover, generation | occurrence | production of the dew condensation of the existing piping 41 can be prevented. Further, in the “bypass state”, the compressor 13 can be effectively cooled by the refrigerant flowing from the bypass pipe 31 to the injection port connection pipe 33.

FIG. 2 is a schematic diagram of a state in which the entire refrigeration circuit 10 is newly installed.
In the configuration of FIG. 2, heat insulation is performed on the pipe 42 arranged in the cooler 11 in the refrigerant pipe 22. The heat insulation treatment is a heat insulating material 43 wound around the surface of the pipe 42. The heat insulating material 43 is provided over a section between the most upstream position in the cooler 11 and the inlet of the evaporator 20, for example, on the pipe 42. Since the heat insulating material 43 is provided at the same time as the cooler 11 newly installed in the installation facility and is not restricted as in the case of the existing piping 41 in FIG. Provided.

In the configuration of FIG. 2, the condensation of the pipe 42 is prevented by the heat insulating material 43, so the refrigerator 12 is used in the “economizer use state”. For this reason, the cooler 11 can be used in a state where the cooling capacity is improved by the economizer 18. In the present embodiment, the “economizer use state” and the “bypass state” can be easily selected by switching the open / close state of the bypass pipe flow path opening / closing valve 37 and the economizer flow path opening / closing valve 36. The structure of the refrigerator 12 does not need to be changed depending on whether or not, and the manufacture and handling of the refrigerator 12 are easy.
The heat insulating material 43 as described above is also provided in the liquid refrigerant pipe 26 extending from the economizer 18 to the cooler 11.

Further, in the “economizer use state”, the control unit increases the opening of the branch pipe expansion valve 35 more than the “bypass state”. For this reason, even if it is a case where a refrigerant | coolant is poured through the economizer 18, sufficient quantity of a refrigerant | coolant can be supplied to the injection port 13a for cooling, and the compressor 13 can be cooled effectively.
Further, the refrigerant cooled through the subcooler 17 passes through the pipe 18 d of the economizer 18, and the refrigerant in the pipe 18 d exchanges heat with the refrigerant expanded by the branch pipe expansion valve 35 through the branch pipe 30 from the subcooler 17. Therefore, since it is further cooled, the degree of supercooling of the refrigerant flowing through the cooler 11 can be increased, and the cooling capacity of the cooler 11 can be improved.

  As described above, according to the embodiment to which the present invention is applied, the refrigerator 12 includes the compressor 13 and the condenser 15, the refrigerant pipe on the upstream side of the compressor 13, and the downstream side of the condenser 15. A refrigerant pipe is connected to the cooler 11, a branch pipe 30 branched from the high-pressure liquid pipe 26 a on the downstream side of the condenser 15 and connected to the cooling injection port 13 a of the compressor 13, and a middle part of the branch pipe 30 An economizer 18 arranged to exchange heat between the refrigerant flowing out of the condenser 15 and the refrigerant flowing through the branch pipe 30, and a bypass pipe 31 connecting the upstream side and the downstream side of the economizer 18 of the branch pipe 30; A flow path through which the refrigerant flowing into the branch pipe 30 passes through the economizer 18 and a flow path through the bypass pipe 31 can be selected. Thereby, when the condensation is likely to occur in the refrigerant pipe 22 due to the installation state on the cooler 11 side, the heat exchange of the refrigerant by the economizer 18 can be stopped by selecting the flow path passing through the bypass pipe 31. Since the temperature of the refrigerant pipe 22 on the 11th side does not greatly decrease, condensation on the refrigerant pipe 22 on the cooler 11 side can be prevented. Further, when it is difficult for condensation to occur in the refrigerant pipe 22 due to the installation state on the cooler 11 side, by selecting a flow path that passes through the economizer 18, the economizer 18 performs heat exchange of the refrigerant, The cooling capacity can be improved and the occurrence of condensation in the refrigerant pipe 22 on the cooler 11 side can be prevented. For this reason, according to the installation state by the side of the cooler 11, dew condensation of the refrigerant | coolant piping 22 can be prevented with a simple structure. Moreover, even if it is a case where any of the flow path which passes along the bypass pipe 31 and the flow path which passes along the economizer 18 is selected, a refrigerant | coolant can be flowed through the cooling injection port 13a, and the compressor 13 can be cooled effectively.

  The refrigerator 12 includes an economizer flow path opening / closing valve 36 that opens and closes a flow path for passing the refrigerant through the economizer 18, and a bypass pipe flow path opening / closing valve 37 that opens and closes the flow path of the bypass pipe 31. The flow path is selected by opening and closing the open / close valve 36 and the bypass pipe flow path open / close valve 37. For this reason, it is possible to easily select the flow path through the economizer 18 and the flow path through the bypass pipe 31 simply by opening and closing the economizer flow path opening / closing valve 36 and the bypass pipe flow path opening / closing valve 37.

Further, since the branch pipe expansion valve 35 that expands the refrigerant is provided in the middle of the branch pipe 30 and upstream of the economizer 18 and the bypass pipe 31, either the flow path that passes through the bypass pipe 31 or the flow path that passes through the economizer 18. Even when selected, the refrigerant expanded by the branch pipe expansion valve 35 can flow through these flow paths.
Further, when the heat insulating material 43 as a heat insulating process is provided in the pipe 42 of the cooler 11, the economizer flow path opening / closing valve 36 is opened and the bypass pipe flow path opening / closing valve 37 is closed, so that the cooler 11 When the existing pipe 41 is not thermally insulated, the economizer flow path opening / closing valve 36 is closed and the bypass pipe flow path opening / closing valve 37 is opened. For this reason, when the heat insulating material 43 is given to the piping 42 of the cooler 11, the heat exchange of the refrigerant can be performed by the economizer 18 to improve the cooling capacity on the cooler 11 side, and the piping 42 on the cooler 11 side. It is possible to prevent the occurrence of condensation. Further, when the existing piping 41 of the cooler 11 is not thermally insulated, the refrigerant can be bypassed with respect to the economizer 18 to prevent condensation on the existing piping 41.

Further, the expansion means is a branch pipe expansion valve 35, and when the flow path that passes through the economizer 18 is selected, the branch pipe expansion valve 35 of the branch pipe expansion valve 35 is larger than when the flow path that passes through the bypass pipe 31 is selected. Since the opening degree is largely controlled, even when the refrigerant is cooled by the economizer 18, a sufficient amount of refrigerant can be supplied for cooling the compressor 13.
Further, since the supercooler 17 for cooling the refrigerant is provided between the condenser 15 and the economizer 18, the refrigerant flowing from the branch pipe 30 to the economizer 18 can be cooled to a lower temperature, and the cooling capacity on the cooler 11 side. Can be improved effectively.

In addition, the said embodiment shows the one aspect | mode which applied this invention, Comprising: This invention is not limited to the said embodiment.
In the said embodiment, although the cooler 11 containing the refrigerant | coolant piping 22 by the side of the cooler 11 demonstrated in FIG. 1 as what was provided, the present invention is not limited to this. When the refrigerator 12 is used in the “bypass state”, it is sufficient that at least the existing pipe 41 is an existing pipe, and a part constituting the cooler 11 other than the existing pipe 41 may be newly installed.
In the above embodiment, the branch pipe 30 has been described as having the economizer connection pipe 32 that branches from the position between the supercooler 17 and the economizer 18 in the high-pressure liquid pipe 26a. The position branched from the liquid pipe 26 a may be a position between the receiver tank 16 and the cooler 11. For example, the branch pipe 30 may be branched from the high-pressure liquid pipe 26 a downstream of the economizer 18.

DESCRIPTION OF SYMBOLS 11 Cooler 12 Refrigerator 13 Compressor 13a Cooling injection port 15 Condenser 17 Supercooler 18 Economizer 22 Refrigerant piping 30 Branch pipe 31 Bypass pipe 35 Branch pipe expansion valve (expansion means)
36 Economizer flow path opening / closing valve 37 Bypass pipe flow path opening / closing valve 43 Heat insulation material (heat insulation treatment)

Claims (2)

In a refrigerator comprising a compressor and a condenser, wherein a refrigerant pipe on the upstream side of the compressor and a refrigerant pipe on the downstream side of the condenser are connected to a cooler,
An economizer provided in a refrigerant pipe downstream of the condenser;
A branch pipe branched from the refrigerant pipe downstream of the economizer and connected to the cooling injection port of the compressor by exchanging heat with the refrigerant flowing out of the condenser flowing through the economizer;
A bypass pipe connecting the upstream side and the downstream side of the economizer of the branch pipe;
An economizer flow path opening / closing valve that opens and closes a flow path for passing refrigerant through the economizer;
A bypass pipe passage opening and closing valve for opening and closing the passage of the bypass pipe;
An expansion valve that expands the refrigerant in the middle of the branch pipe and upstream of the economizer and the bypass pipe;
A freezer comprising the above. 2. The refrigeration according to claim 1, wherein when the economizer flow path opening / closing valve is opened, the opening degree of the expansion valve is controlled to be larger than when the bypass pipe flow path opening / closing valve is opened. Machine.

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