JPH10267494A - Cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance heat-exchange efficiency of a cooler by providing a refrigerant circuit for coupling a compressor, a condenser and a plurality of coolers, and a brine circuit coupling a refrigeration load and the cooler and switching the plurality of coolers in the refrigerant circuit between series coupling and parallel coupling through a switching unit. SOLUTION: The refrigerant channels of coolers 10, 11 are connected in series to constitute a series refrigerant circuit 16 while the brine channels thereof are connected in series and in parallel to constitute a series brine circuit 19 and a parallel brine circuit 20. When the circuits 16, 19 are used, refrigerant switching valves 18a, 18c are closed while a refrigerant switching valve 18b is opened and brine switching valves 21a, 21c are closed while a brine switching valve 21b is opened. When the circuits 16, 20 are used, the refrigerant switching valves 18a, 18c are closed while the refrigerant switching valve 18b is opened and brine switching valves 21a, 21c are opened while the brine switching valve 21b is closed. Switching is performed based on the variation of brine temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device having a plurality of coolers, for example, two coolers.

[0002]

2. Description of the Related Art FIG. 23 is a block circuit diagram of a conventional cooling device disclosed in Japanese Patent Application Laid-Open No. 7-43025. Here, 101 is a compressor, 102 is a four-way valve, 103 is a heat source side heat exchanger, 104 is a blower for a heat source side heat exchanger, 105
Is an accumulator, 106 is a pressure reducing device using a pulse motor driven refrigerant control valve, 110 is a use side heat exchanger, 111
Is an on-off valve, 113 is a blower for a use side heat exchanger, 120 is a regenerator, 121 is a heat exchanger for a regenerator provided in the regenerator,
122 is a refrigerant liquid pump, 123 is a check valve, 124 is an on-off valve, 125 is a regenerator, 130 is a temperature sensor for detecting indoor air temperature, 131 is a temperature sensor, and 132 is a regenerator 12
A liquid level sensor for detecting the liquid level of the cold storage agent 125 within 0;
3 is a pressure sensor and 134 is a temperature sensor. The cooling device further includes a control device for controlling the refrigeration cycle, the compressor 1
01 drive device, a pump drive device, and the like.

FIG. 24 is a schematic explanatory view of the heat source side heat exchanger 103. The heat source side heat exchanger 103 is provided with a number of long refrigerant pipes 103a provided with a large number of cooling fins 103b on the outer periphery. It is cooled by a dexterous blower 104 and changed into a refrigerant liquid. FIG. 25 is a schematic explanatory view of the use-side heat exchanger 110. User side heat exchanger 11
Numeral 0 denotes a plurality of long refrigerant tubes 110a provided with a number of cooling fins 110b on the outer periphery.
0a and the blower 1 for the use side heat exchanger
The cooling air is supplied by performing heat exchange with the room air sent by the cooling device 13.

Next, the operation of the cooling device will be described. In FIG. 23, the refrigerant circulates in the piping system shown by the thick line in the direction of the arrow. That is, the refrigerant discharged from the compressor 101 passes through the four-way valve 102 and passes through the heat source side heat exchanger 10.
After being condensed and supercooled in 3 and decompressed by the refrigerant control valve 106, it merges with the refrigerant supplied from the heat storage tank heat exchanger 121 and the refrigerant liquid pump 122, passes through the on-off valve 111, and passes through the use side heat exchanger. 110. The gaseous refrigerant that has exchanged heat with the indoor air in the use-side heat exchanger 110 is supplied to the four-way valve 1.
02, returning to the accumulator 105, a part of the heat is exchanged with the regenerator 25 in the heat storage tank heat exchanger 121 to be liquefied and sucked into the refrigerant liquid pump 122, and the rest is sucked into the compressor 101.

In a normal cooling operation, the compressor 10
1, four-way valve 102, use side heat exchanger 110, on-off valve 11
1, control valve 106, heat source side heat exchanger 103, four-way valve 10
2. The refrigerant circulates in the order of the accumulator 105 and the compressor 101, and the cooling operation is performed with the use-side heat exchanger 110 serving as an evaporator.

[0006]

The conventional cooling device constructed as described above has a room for improving the heat exchange efficiency, and the use side heat exchanger, that is, the cooler has only a single use. There was a problem that it was not possible. Further, the heat source side heat exchanger including the long refrigerant pipes and the cooling fins, that is, the cooler which is the condenser and the use side heat exchanger, has a large structure, so that the cooling device is also large and complicated. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has been made to improve the heat exchange efficiency of a cooler and to make it possible to utilize a large amount of cooling, and to provide a compact and lightweight cooling device having a simple structure. The purpose is to gain.

[0007]

The invention according to claim 1 is
A refrigerant circuit connecting the compressor, the condenser and the plurality of coolers,
A cooling device comprising a refrigeration load and a brine circuit connecting the plurality of coolers, wherein each of the plurality of coolers of the refrigerant circuit is configured in series and in parallel, And a refrigerant circuit switching device for switching each refrigerant circuit.

According to a second aspect of the present invention, there is provided a cooling apparatus including a refrigerant circuit for connecting a compressor, a condenser and a plurality of coolers, and a brine circuit for connecting a refrigeration load and the plurality of coolers. , Each of which includes a plurality of coolers of the brine circuit arranged in series and in parallel, and a brine circuit switching device that switches between the series and the parallel brine circuits.

According to a third aspect of the present invention, there is provided a cooling device comprising a refrigerant circuit for connecting a compressor, a condenser and a plurality of coolers, and a brine circuit for connecting a refrigeration load and the plurality of coolers. A refrigerant circuit comprising a plurality of refrigerant circuits in series and in parallel, a refrigerant circuit switching device for switching the series and parallel refrigerant circuits, and a plurality of brine circuit coolers in series. And a brine circuit switching device configured to switch between the series and parallel brine circuits.

According to a fourth aspect of the present invention, in the first or third aspect of the present invention, the switching of the brine circuit is performed based on a change in the brine temperature.

According to a fifth aspect of the present invention, in the first or third aspect of the present invention, the switching of the refrigerant circuit is performed based on a change in the refrigerant temperature of the cooler.

According to a sixth aspect of the present invention, in the first or third aspect of the present invention, the switching of the refrigerant circuit is performed based on a change in the refrigerant pressure of the cooler.

According to a seventh aspect of the present invention, in the second or third aspect, the switching of the brine circuit is performed based on a change in the brine temperature.

According to an eighth aspect of the present invention, in the second aspect of the present invention, the respective coolers constituting the parallel brine circuit are connected to the same refrigeration load.

According to a ninth aspect of the present invention, in the second aspect of the invention, the respective coolers constituting the parallel brine circuit are connected to different refrigeration loads.

A tenth aspect of the present invention is the invention according to the ninth aspect, wherein the plurality of coolers have different heat exchange capacities, and these coolers are connected in accordance with the magnitude of the refrigeration load. It is.

The invention according to claim 11 is the invention according to claims 1 to 1
In the invention according to the present invention, the cooler is formed by a laminated plate heat exchanger.

The invention according to claim 12 is the invention according to claims 1 to 1
In the invention according to the first aspect, the condenser is formed by a laminated plate heat exchanger.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a block circuit diagram of a cooling apparatus according to the present invention, in which two coolers composed of a laminated plate heat exchanger, that is, a first cooler 10 and a second cooler 11 are provided.
Having. The structure of the first cooler 10 is shown in FIGS. 6 to 9, and the structure of the second cooler 11 is shown in FIGS. 10 to 13, respectively. Here, FIG. 6 and FIG. 10 are front views of the cooler, FIG. 7 and FIG.
8 and 12 are partial cross-sectional side views showing the inside of the cooler, and FIGS. 9 and 13 are schematic cross-sectional plan views showing the inside of the cooler.
These coolers 10 and 11 have front cover plates to 1
Between the outer cover plates 10a, 11a and the rear cover plates 10d, 11d, a brazing material 10b, 11b and a hermetically-formed thin channel plate 10 formed by stamping.
A large number of layers c and 11c are alternately laminated by a predetermined number (FIGS. 7 and 11), and in a vacuum heating furnace (not shown), the laminated edge and the formed projection P are integrally formed by line contact by vapor deposition brazing (FIG. 9, 13), in which a flow path bent in the vertical direction is formed (FIGS. 7 to 9, 11).
13). Reference numerals 12 and 13 denote the brine passages of the respective coolers, which are composed of upper A-side nozzles 12a and 13a and lower A-side nozzles 12b and 13b, while 14 and 15 denote the refrigerant passages of the respective coolers and the lower B side. Nozzles 14a, 15a
And upper B-side nozzles 14b, 15b, and the brine flow paths 12, 13 and the refrigerant flow paths 14, 15 are provided alternately in the plate stacking direction of the stacked plate heat exchanger.
The stacked plate heat exchangers are configured to flow so as to face each other in the vertical direction (FIGS. 8 and 12).

Reference numeral 16 denotes a first cooler 10 and a second cooler 1
It is a series refrigerant circuit in which one refrigerant flow path is connected in series. The lower B side nozzle 14a of the first cooler 10 is connected to the apparatus refrigerant circuit 5 and passes through the refrigerant flow path 14 to the upper B side nozzle 14a.
b to one end of the series refrigerant circuit 16. Further, the other end of the series refrigerant circuit 16 is connected to the lower B-side nozzle 15a of the second cooler 11, and is connected to the apparatus refrigerant circuit 5 again through the refrigerant flow path 15 at the upper B-side nozzle 15b. Reference numeral 17 denotes a parallel refrigerant circuit in which the refrigerant flow paths of the first cooler 10 and the second cooler 11 are connected in parallel, and a refrigerant branch point 17c provided upstream of the refrigerant circuit of the first cooler 10 and a second refrigerant circuit 17. Cooler 1
A first parallel refrigerant circuit 17a provided to communicate between refrigerant branch points 17d provided upstream of the first refrigerant circuit, and a refrigerant branch point 17 provided downstream of the refrigerant circuit of the first cooler 10
e and a second parallel refrigerant circuit 17b provided to communicate between refrigerant branch points 17f provided downstream of the refrigerant circuit of the second cooler 11. 18 is a refrigerant circuit switching device, a first refrigerant switching valve 18a provided in the first parallel refrigerant circuit 17a, a second refrigerant switching valve 18b provided in a circuit between the refrigerant branch points 17e, 17d, And a third refrigerant switching valve 18c provided in the second parallel refrigerant circuit 17b.

Reference numeral 19 denotes a first cooler 10 and a second cooler 1
It is a series brine circuit in which one brine channel is connected in series. The upper A-side nozzle 12a of the first cooler 10 is connected to the lower A-side nozzle 13b of the second cooler 11 via the series brine circuit 19 and the lower A-side nozzle 1 of the first cooler 10.
2 b is connected to the brine merger 22, and the upper A-side nozzle 13 a of the second cooler 11 is connected to the brine distributor 23. The brine merger 22 and the brine distributor 23 are connected to a refrigerating device 24, which is a refrigerating load, and form a circulation circuit together with the first cooler 10 and the second cooler 11, and are operated by a brine pump 24a. The brine is cycled. Reference numeral 20 denotes a parallel brine circuit in which the brine flow passages of the first cooler 10 and the second cooler 11 are connected in parallel. Parallel brine circuit 20a connected to a brine junction 22 via a branch point 20d provided upstream of the circuit through the cooler 11, and a brine provided downstream of the circuit of the first cooler 10 from the brine branch point 20c. The first cooler 1 via the branch point 20e
0 and a second parallel brine circuit connected to the brine merger 22. Reference numeral 21 denotes a brine circuit switching device which includes a first brine switching valve 21a provided in a circuit between the brine branch points 20c and 20e, and a second brine switching valve 21b provided in a circuit between the brine branch points 20d and 20e. And a third brine switching valve 21c provided downstream of the circuit at the brine branch point 20d.

1 is a compressor, 2 is a condenser, 3 is an expansion valve provided upstream of the circuit at the refrigerant branch point 17c, and 2
Reference numeral 5 denotes a brine temperature detector provided in the brine flow divider 23.

Next, the operation of the cooling device will be described. First, the case where the series refrigerant circuit 16 and the series brine circuit 19 are used will be described. In this configuration, the first and third refrigerant switching valves 18a and 18c in the refrigerant circuit are closed, and the second refrigerant switching valve 18b is opened.
First and third brine switching valves 21 in a brine circuit
This is achieved by closing the a and 21c and opening the second brine switching valve 21b. The refrigerant and the brine flow in the bold line circuit in FIG. 2 (the refrigerant flows in the direction of the dashed arrow and the brine flows in the direction of the arrow, respectively) ). That is, the refrigerant gas compressed by the compressor 1 enters the condenser 2 via the device refrigerant circuit 5 to become a refrigerant liquid, and is supplied to the first cooler 1 via the expansion valve 3.
0 from the lower B-side nozzle 14a to the refrigerant flow path 14, from the upper B-side nozzle 14b to the refrigerant flow path 15 from the lower B-side nozzle 15a of the second cooler 11 through the serial refrigerant circuit 16, It enters the device refrigerant circuit 5 from the upper B side nozzle 15b and returns to the compressor 1. On the other hand, the brine is supplied from the refrigerating device 24 to the upper A-side nozzle 1 of the second cooler 11 by the brine pump 24 a through the brine distributor 23.
3a, is introduced into the brine flow path 13, from the lower A-side nozzle 13b, is introduced into the brine flow path 12 from the upper A-side nozzle 12a of the first cooler 10 via the series brine circuit 19, and from the lower A-side nozzle 12b. It exits and is supplied to the refrigerating device 24 via the brine merger 22. Thus, the refrigerant flow path 1 in the second and first coolers 11, 10
The refrigerant flowing through the refrigerant flow passages 5 and 14 and the brine flowing through the brine flow passages 13 and 12 adjacent to the refrigerant flow passages 15 and 14 in the laminating direction exchange heat to generate cold brine.
4 are cooled.

Next, the case where the series refrigerant circuit 16 and the parallel brine circuit 20 are used will be described. This configuration includes first and third refrigerant switching valves 18a and 18c of the refrigerant circuit.
Is closed and the second refrigerant switching valve 18b is opened, while the first and third brine switching valves 21 of the brine circuit are closed.
This is achieved by opening the a and 21c and closing the second brine switching valve 21b. The refrigerant and the brine flow through the bold line circuit in FIG. 3 (the refrigerant flows in the direction of the dashed arrow, and the brine flows in the direction of the arrow, respectively). ). One of the brines that has exited the refrigerating device 24 by the brine pump 24a and is divided by the brine distributor 23 is connected to the first parallel brine circuit 2.
Using 0a, it is introduced into the brine flow path 13 of the second cooler 11 from the brine branch point 20c, and then introduced into the brine merger 22 from the brine branch point 20d through the third brine switching valve 21c. You. The other brine that has been diverted by the brine diverter 23 is connected to the first brine switching valve 21a and the brine branch point 20e from the brine branch point 20c by using the second parallel brine circuit 20b.
, Is introduced into the brine flow path 12 of the first cooler 10, further introduced into the brine merger 22, merges with the one brine, and is supplied to the refrigerating device 24. In addition,
The flow of the refrigerant is the same as that described above, and heat is exchanged between the refrigerant and the brine in the first and second coolers 10 and 11.

Here, the cooling capacity in the series brine circuit 19 is Q _c1 (kcal / h), the cooling capacity in the parallel brine circuit 20 is Q _c2 (kcal / h), and the brine flow rate is W (m ³
/ h), brine specific gravity γ (kg / m ³ ), specific heat C (kcal / k
g · ° C.), the temperature of the brine flowing out of the refrigerating device 24 into the circuit is t ₁ (° C.), the temperature of the brine flowing out of the second cooler 11 is t ₂ (° C.), and the temperature of the brine flowing out of the first cooler 10 is Assuming that the temperature is t ₃ (° C.), the following equation is established.

Q _c1 = W × γ × c × {(t ₂ −t ₁ ) + (t ₃ −t ₂ )} = W × γ × c (t ₃ −t ₁ )

Q _c2 = 2W × γ × c × {(t ₂ −t ₁ ) + (t ₃ −t ₂ )} = 2W × γ × c (t ₃ −t ₁ )

Here, since Q _c1 = Q _c2 , according to the above equation,
In the case of a serial brine circuit, the amount of brine (W) flowed by the brine pump 24a is ２ of that in the case of a parallel brine circuit, and the pump power is reduced. In the case of a parallel brine circuit, the brine temperature difference (t ₃
−t ₁ ) is _１ ／ of that in the case of the series brine circuit, and the temperature control width on the load side is reduced, so that it is easy to keep the temperature of the refrigeration load uniform. The switching of the brine circuit is performed, for example, by detecting the brine temperature after cooling the refrigerating load by the refrigerating device 24 with the brine temperature detector 25,
When the temperature of the brine temperature detector 25 reaches a preset temperature set value, the brine circuit switching device 21 can be operated to switch the circuit.

Next, the case where the parallel refrigerant circuit 17 and the series brine circuit 19 are used will be described. This configuration,
The first and third refrigerant switching valves 18a, 18c of the refrigerant circuit are opened and the second refrigerant switching valve 18b is closed, while the first and third brine switching valves 21a, 21 of the brine circuit are opened.
This is achieved by closing the second valve c and opening the second brine switching valve 21b. The refrigerant and the brine flow in the circuit indicated by the thick line in FIG. 4 (the refrigerant flows in the direction of the dashed arrow, and the brine flows in the direction of the arrow, respectively). Refrigerant branch point 17c of device refrigerant circuit 5
Is passed through the first parallel refrigerant circuit 17a via the switching valve 18a and passes through the refrigerant flow path 15 of the second cooler 11.
And flows into the device refrigerant circuit 5 through heat exchange with the brine flowing in the brine flow path 13 facing the same. The other refrigerant from the refrigerant branch point 17 c is introduced into the refrigerant flow path 14 of the first cooler 10, and is cooled by the brine cooled by the second cooler 11, which is opposed to the brine flow path 12. After replacement and further cooling of the brine, the refrigerant branch point 17e, the third
Flows through the switching valve 18c and the refrigerant branch point 17f into the device refrigerant circuit 5, merges with the refrigerant flowing from the first parallel refrigerant circuit 17a, and returns to the compressor 1.

Finally, the case where the parallel refrigerant circuit 17 and the parallel brine circuit 20 are used will be described. This configuration includes first and third refrigerant switching valves 18a and 18c of the refrigerant circuit.
Is opened and the second refrigerant switching valve 18b is closed, while the first and third brine switching valves 21 of the brine circuit are closed.
This is achieved by opening the a and 21c and closing the second brine switching valve 21b, so that the refrigerant and the brine flow through the bold line circuit in FIG. ). As described above, the refrigerant is supplied to the second cooler 11 by the first parallel refrigerant circuit 17a.
And is introduced into the first cooler 10 by the second parallel refrigerant circuit 17b. On the other hand, the brine is introduced into the second cooler 11 by the first parallel brine circuit 20a, and is introduced into the first cooler 10 by the second parallel brine circuit 20b. Here, the brine is cooled by exchanging heat with the refrigerant in the respective coolers 10 and 11, and then combined by the brine merger 22 and supplied to the refrigerating device 24.

As described above, according to the cooling device of the present invention, the flow rate of the refrigerant is reduced by the parallel refrigerant circuit 17 from the initial stage of freezing to the arrival of the predetermined temperature, thereby eliminating the pressure loss.
After the brine temperature reaches a predetermined temperature, the refrigerant flow can be freely selected, such as increasing the flow rate of the refrigerant by the serial refrigerant circuit 16, so that the efficiency of heat exchange with the brine can be improved. Further, by selecting a brine circuit, the power of the brine pump can be reduced, and the temperature of the refrigeration load can be more preferably adjusted.

The switching of the refrigerant circuit can be performed by various methods. For example, the brine temperature after cooling the refrigerating load by the refrigerating device 24 is detected by the brine temperature detector 25, and when the brine temperature detector 25 reaches a preset temperature set value, the refrigerant circuit switching device 18 is turned off. It can be set to operate and switch the circuit.

As shown in the partial cross-sectional view of the first cooler in FIG. 14, a refrigerant medium evaporation temperature detector 30 for detecting the refrigerant medium evaporation temperature is installed near the refrigerant outlet of the refrigerant channel 14. This can be performed based on the refrigerant medium evaporation temperature detector 30. That is, the refrigerant evaporating temperature due to heat exchange is detected by the refrigerant evaporating temperature detector 30, and when this reaches a predetermined temperature, for example, −10 ° C., the first and third refrigerant circuit switching devices 18 are controlled by an electric command (not shown). The switching valves 18a and 18c are closed and the second switching valve 1 is closed.
8b by opening the parallel refrigerant circuit 17 to the serial refrigerant circuit 1
6. The switching of the refrigerant circuit according to this example is shown in the explanatory diagram of FIG. 15 showing the relationship between the refrigerant evaporation temperature and the cooling capacity.

In place of the refrigerant evaporation temperature detector 30,
A refrigerant evaporating pressure detector 31 for detecting refrigerant evaporating pressure is provided near the refrigerant outlet of the refrigerant flow path. The refrigerant evaporating pressure after heat exchange with the brine is detected. When the pressure reaches a preset pressure, the circuit switching device 18 is activated. By operating, the parallel refrigerant circuit 17 may be switched to the serial refrigerant circuit 16 in the same manner as in the previous example.

Embodiment 2 FIG. 16 is a block circuit diagram of a cooling device according to Embodiment 2 of the present invention. Here, the compressor 1, the condenser 2, the expansion valve 3, the first cooler 10
The second cooler 11 is connected to the apparatus cooling circuit 5 and the series refrigerant circuit 16. At the same time, the first cooler 10
The second cooler 11 is connected to the refrigeration unit 24 having the same refrigeration load by the second parallel brine circuit 20b and the second cooler 11 by the first parallel brine circuit 20a via the brine merger 22 and the brine shunt 23. Connected. According to this, the brine cooled by each of the coolers 10 and 11 is merged by the brine merger 22, and the brine at a constant temperature is simultaneously supplied to the refrigerating device 24.

Embodiment 3 FIG. 17 is a block circuit diagram of a cooling device according to a third embodiment of the present invention, which is different from the second embodiment in the configuration of a brine circuit. That is, this is an example in which there are two refrigeration loads, the first cooler 10 is connected to the first refrigeration load 32 by the second parallel brine circuit 20b, and the second cooler 11 is connected to the first parallel load. It is connected to the second refrigeration load 33 by a brine circuit 20a. The refrigerant flows from the first cooler 10 to the second cooler 11 through the serial refrigerant circuit 16, and the first cooler 10 has a good heat exchange efficiency and a sufficient amount of brine by fresh refrigerant liquid. Although cooled, the refrigerant after the heat exchange in the first cooler 10 is a mixed refrigerant of the refrigerant liquid and the refrigerant gas, so that the second cooler 11 slightly reduces the heat exchange efficiency to cool the brine. Will be. Therefore, the first cooler 1
The first refrigeration load 32 connected to 0 is a refrigeration room 32 for freezing meat and the like, for example, and the second refrigeration load 33 connected to the second cooler 11 is a refrigerator room for cooling vegetables and the like. It is better to hit.

Embodiment 4 FIG. FIG. 18 is a block circuit diagram of a cooling device according to Embodiment 4 of the present invention. This is because the first cooler of the third embodiment is replaced by a third cooler 34 having a large heat exchange rate, and the second cooler of the third embodiment is replaced by a fourth cooler 35 having a small heat exchange rate. Each has been replaced. Thus, the third cooler 3 can supply the ultra-low temperature brine to the first refrigeration load (for example, a freezing room), and the fourth cooler 4 can supply the brine having a higher temperature than the third cooler 3 to the second cooler. It can be supplied to a refrigeration load (for example, a refrigerator compartment). In this case, the heat exchange rate of the cooler can be arbitrarily changed by changing the number of laminated plates of the cooler.

Although the first to fourth embodiments show examples in which two coolers are combined, it goes without saying that two or more coolers may be used in the present invention. In the second to fourth embodiments, the series refrigerant circuit 1 is used as the refrigerant circuit.
Although 6 was used, it is also possible to use a parallel refrigerant circuit 17 as the refrigerant circuit.

Embodiment 5 19 to 22 show the structure of the condenser used in the present invention. FIG. 19 is a front view, FIG. 20 is an assembly configuration diagram, FIG. 21 is a partial sectional side view showing the inside of the condenser, and FIG. FIG. 2 is a schematic sectional plan view showing the inside of the condenser. Here, reference numeral 26 denotes a condenser composed of a laminated plate heat exchanger. Between the front cover plate 26a and the rear cover plate 26d, a plurality of brazing materials 26b and a thin channel plate 26c of a herringbone type are alternately laminated ( 20), in a vacuum heating furnace (not shown), the laminating edge and the forming projection P are vapor-deposited and brazed to be integrally formed by line contact (FIG. 22), and a flow path bent in the vertical direction is formed (FIG. 22). 20 to 2
2). Reference numeral 27 denotes a refrigerant flow path, and the upper A side nozzle 27a and the lower A side
28 is a cooling water flow path and a lower nozzle B
It comprises a side nozzle 28a and an upper B side nozzle 28b. The refrigerant flow paths 27 and the cooling water flow paths 28 are provided alternately in the plate laminating direction of the laminated plate heat exchanger, and are configured to flow facing each other in the vertical direction of the laminated plate heat exchanger (FIG. 21).

This condenser 26 is used in the first to fourth embodiments and operates as follows. The refrigerant gas compressed by the compressor 1 is introduced into the inside of the condenser from the upper A-side nozzle 27a of the refrigerant flow path 27 of the condenser 26, and is sequentially passed through the refrigerant flow path 2
The cooling water flows into the cooling water flow path 28 adjacent in the laminating direction while flowing from the top to the bottom, and is cooled by heat exchange with the cooling water to be converted into a refrigerant liquid. And
This refrigerant liquid exits from the lower A-side nozzle 27b and is supplied to a predetermined cooler. Thus, the condenser composed of the laminated plate heat exchanger changes the refrigerant gas into the refrigerant liquid.

[0041]

According to the first aspect of the present invention, a refrigerant circuit comprising a plurality of coolers constituting a refrigerant circuit in series and parallel, respectively, and a switching device for the refrigerant circuit are provided.
It is possible to select series or parallel according to the brine temperature or the like. For example, the heat exchange efficiency can be improved by lowering the refrigerant speed by a parallel refrigerant circuit to eliminate pressure loss in the initial stage of refrigeration and increasing the refrigerant flow rate later by a serial refrigerant circuit.

According to the second aspect of the present invention, since a plurality of coolers constituting the brine circuit are provided in series and in parallel, respectively, and a switching device for the brine circuit is provided, the brine pump is used. The power flow can be reduced by reducing the flow rate and the flow can be reduced. In addition, the difference in brine temperature is reduced and the temperature of the load becomes uniform, thereby improving the refrigeration quality.

According to the third aspect of the present invention, when the refrigerant circuits are connected in series or in parallel, the brine circuit can be switched in series or in parallel, and the effects of the first and second aspects can be simultaneously achieved.

Further, according to the fourth aspect of the present invention, it is possible to accurately select the refrigerant circuit in series or in parallel according to the brine temperature.

Further, according to the fifth aspect of the present invention, the series and parallel switching of the refrigerant circuit can be accurately performed according to the refrigerant temperature.

Further, according to the sixth aspect of the present invention, the series and parallel switching of the refrigerant circuit can be accurately performed according to the refrigerant pressure.

According to the seventh aspect of the present invention, it is possible to accurately select the series and parallel states of the brine circuit according to the brine temperature.

According to the eighth aspect of the present invention, since the respective coolers constituting the parallel brine circuit are connected to the same refrigeration load, brine of a constant temperature is simultaneously supplied to reduce the refrigeration temperature. It is possible to stabilize uniformly.

According to the ninth aspect of the present invention, the respective coolers constituting the parallel brine circuit are connected to different refrigeration loads, so that a plurality of refrigeration loads can be cooled simultaneously and in accordance with the refrigeration loads. There is an effect that can be.

According to the tenth aspect of the present invention, for example, the first cooler of the parallel brine circuit has a large capacity to generate ultra-low temperature brine, and the second cooler has a small capacity of 0 ° C. By configuring to generate neighboring brines,
There is an effect that cooling according to the refrigeration load can be performed.

Further, according to the eleventh aspect of the present invention, since the cooler is constituted by a laminated plate heat exchanger, there is an effect that the installation area can be reduced and the heat exchange efficiency can be improved.

Further, according to claim 12 of the present invention,
Since the condenser is constituted by the laminated plate heat exchanger, there is an effect that the installation space is reduced in a small size and the heat exchange efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a cooling device according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a series refrigerant circuit and a series brine circuit in FIG. 1;

FIG. 3 is a circuit configuration diagram showing a series refrigerant circuit and a parallel brine circuit in FIG. 1;

FIG. 4 is a circuit configuration diagram showing a parallel refrigerant circuit and a series brine circuit in FIG. 1;

FIG. 5 is a circuit configuration diagram showing a parallel refrigerant circuit and a parallel brine circuit in FIG. 1;

FIG. 6 is a front view showing a first cooler used in the first embodiment.

FIG. 7 is an assembly configuration diagram of a first cooler.

FIG. 8 is a partial cross-sectional side view showing the inside of the first cooler.

FIG. 9 is a schematic sectional plan view showing the inside of the first cooler.

FIG. 10 is a front view showing a second cooler used in the first embodiment.

FIG. 11 is an assembly configuration diagram of a second cooler.

FIG. 12 is a partial cross-sectional side view showing the inside of a second cooler.

FIG. 13 is a schematic sectional plan view showing the inside of the second cooler.

FIG. 14 is a partial cross-sectional side view showing the upper inside of the first cooler.

FIG. 15 is an explanatory diagram showing a relationship between a refrigerant evaporation temperature and a cooling capacity.

FIG. 16 is a block circuit diagram of a cooling device according to a second embodiment of the present invention.

FIG. 17 is a block circuit diagram of a cooling device according to Embodiment 3 of the present invention.

FIG. 18 is a block circuit diagram of a cooling device according to Embodiment 4 of the present invention.

FIG. 19 is a front view of a condenser used in Embodiment 5 of the present invention.

FIG. 20 is an assembly configuration diagram of a condenser.

FIG. 21 is a partial sectional side view showing the inside of the condenser.

FIG. 22 is a schematic sectional plan view showing the inside of the condenser.

FIG. 23 is a block circuit diagram of a conventional cooling device.

FIG. 24 is a schematic explanatory view of a heat source-side heat exchanger used in FIG.

FIG. 25 is a schematic explanatory view of the use-side heat exchanger used in FIG. 23.

[Explanation of symbols]

10 first cooler, 11 second cooler, 12, 13
Brine flow path, 12a, 13a Upper A side nozzle, 1
2b, 13b Lower B side nozzle, 14, 15 refrigerant flow path,
14a, 15a Lower B side nozzle, 14b, 15b Upper B side nozzle, 16 series refrigerant circuit, 17 parallel refrigerant circuit, 17a first parallel refrigerant circuit, 17b second parallel refrigerant circuit, 17c, 17d, 17e, 17f refrigerant Branch point, 18 refrigerant circuit switching device, 18a first refrigerant switching valve, 18b second refrigerant switching valve, 18c third refrigerant switching valve, 19 series brine circuit, 20 parallel brine circuit, 20a first parallel brine circuit , 20b second parallel brine circuit, 20c, 20d, 20e brine branch point, 21 brine circuit switching device, 21a first brine switching valve, 21b second brine switching valve, 21c
Third brine switching valve, 22 brine merger, 23
Brine splitter, 24 refrigeration system, 25 brine temperature detector, 26 condenser, 27 refrigerant flow path, 27a upper A side nozzle, 27b lower A side nozzle, 28 cooling water flow path, 28a lower B side nozzle, 28b upper B side Nozzle, 30 refrigerant evaporating temperature detector, 31 refrigerant evaporating pressure detector, 32 first refrigeration load (refrigeration room), 33 second refrigeration load (refrigeration room), 34 third cooler, 35 fourth cooling vessel.

Continued on the front page (72) Inventor Hironori Satomi Mitsubishi Electric Engineering Co., Ltd. 2-6-1 Otemachi, Chiyoda-ku, Tokyo

Claims (12)

[Claims] 1. A cooling device comprising: a refrigerant circuit for connecting a compressor, a condenser and a plurality of coolers; and a brine circuit for connecting a refrigeration load and the plurality of coolers. A cooling device comprising: a refrigerant circuit configured to include a plurality of coolers in series and in parallel; and a refrigerant circuit switching device that switches between the series and parallel refrigerant circuits. 2. A cooling device comprising: a refrigerant circuit connecting a compressor, a condenser, and a plurality of coolers; and a brine circuit connecting a refrigeration load and the plurality of coolers, wherein the cooling circuit includes a plurality of the brine circuits. A cooling circuit comprising: a plurality of brine circuits configured in series and in parallel with each other; and a brine circuit switching device that switches between the series and parallel brine circuits. 3. A cooling device comprising: a refrigerant circuit connecting a compressor, a condenser, and a plurality of coolers; and a brine circuit connecting a refrigeration load and the plurality of coolers. Refrigerant circuits each having a cooler configured in series and in parallel, a refrigerant circuit switching device that switches each serial and parallel refrigerant circuit, and a plurality of coolers in the brine circuit are configured in series and in parallel, respectively. And a brine circuit switching device for switching between the series and parallel brine circuits. 4. The cooling device according to claim 1, wherein the switching of the refrigerant circuit is performed based on a change in brine temperature. 5. The cooling device according to claim 1, wherein the switching of the refrigerant circuit is performed based on a change in the refrigerant temperature of the cooler. 6. The cooling device according to claim 1, wherein the switching of the refrigerant circuit is performed based on a change in refrigerant pressure of a cooler. 7. The cooling device according to claim 2, wherein the switching of the brine circuit is performed based on a change in brine temperature. 8. The cooling device according to claim 2, wherein each of the coolers forming the parallel brine circuit is connected to the same refrigeration load. 9. The cooling device according to claim 2, wherein each of the coolers constituting the parallel brine circuit is connected to a different refrigeration load. 10. The cooling device according to claim 9, wherein the plurality of coolers have different heat exchange capacities, and these coolers are connected in accordance with the magnitude of the load of the refrigeration load. 11. The cooling device according to claim 1, wherein said cooler is formed by a laminated plate heat exchanger. 12. The cooling device according to claim 1, wherein the condenser is formed by a laminated plate heat exchanger.