JP3470728B2 - refrigerator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a general refrigerator, more specifically, a vapor compression refrigerator, an absorption refrigerator, an adsorption refrigerator and the like.

[0002]

2. Description of the Related Art Conventional vapor compression refrigerators have been
It consists of a compressor, a condenser, a liquid receiver, an expansion valve, and a refrigeration circuit in which piping is connected in this order to the evaporator, and it is known that it is effective to give a supercooling degree to the refrigerant at the inlet of the expansion valve in order to improve performance. There is. Therefore, for example, as in the conventional refrigerator shown in FIG. 10, the compressor 1, the condenser 2, the liquid receiver 3, the cooling heat exchanger 6, the expansion valve 4, and the evaporator 5 are connected in this order by the pipe 9. The refrigerating circuit described above and a vehicle cooling device similarly disclosed in Japanese Patent Laid-Open No. 4-92714 have a condenser and a cooling heat exchanger arranged on the inlet side and the outlet side of the liquid receiver. is there.

In such a vapor compression refrigerating machine, a cooling heat exchanger is arranged on the outlet side of the liquid receiver so that the saturated liquid refrigerant discharged from the liquid receiver exchanges heat with low temperature air or low temperature water. It further cools and makes it possible to improve the performance of the refrigerator in particular.

[0004]

However, according to this type of refrigerator, in the conventional example, the structure of the cooling heat exchanger 6 arranged on the outlet side of the liquid receiver 3 is U-shaped. It is a structure of a general heat exchanger having a wave-shaped heat radiation fin between the pipe and the pipe having a shape in which a plurality of diffraction lines are returned on the same plane,
Further, the one disclosed in Japanese Patent Laid-Open No. 4-92714,
The cooling heat exchanger arranged on the outlet side of the liquid receiver has the same structure as the condenser. Therefore, both of them have a problem that the structure of the cooling heat exchanger increases the volume, weight and cost.

Further, in the steady operation of the refrigerator, since the refrigerating load is small and improvement of the refrigerating performance is not required so much, the conventional example and the one disclosed in JP-A-4-92714 are always operated. However, there are problems that the pressure loss of the refrigerant increases and that the electric power increases due to the addition of the blower. The present invention has been made in order to solve such a problem, and by cooling the refrigerant at the inlet of the expansion valve of the refrigerator only at the time of starting by a simple method, a refrigerator having improved performance at the time of starting is provided. The purpose is to provide.

[0006]

According to a first aspect of the present invention, there is provided a refrigerator according to the present invention, wherein a refrigerant compressor, a condenser, a liquid receiver, a pressure reducing device and an evaporator are connected by piping. A refrigerator, in which a cooler capable of absorbing and evaporating moisture in the outside air is arranged between the liquid receiver and the pressure reducing device,
The moisture absorbed in the cooler is evaporated by the temperature of the refrigerant at the outlet side of the liquid receiver.

Further, in the refrigerator according to the present invention, in claim 2, the pipe through which the refrigerant flows, the fins fixed to the outer peripheral surface of the pipe and extending outward in the radial direction, and the moisture contacting at least the outer surface of the fin The cooler is provided with a hygroscopic material capable of absorbing and evaporating. Further, the refrigerator according to the present invention, in claim 3 or 4, preferably, the hygroscopic material adhered to an outer surface of the fin or an outer surface of the pipe, or both, the fin or the pipe, and It is characterized by comprising the cooler having the hygroscopic material filled between the fin or the breathable member covering the pipe.

Further, in the refrigerator according to the present invention, in claim 5, preferably, zeolite, silica gel, activated alumina, activated carbon, hygroscopic polymer resin, aqueous solution of lithium bromide,
It is characterized by comprising the cooler having one or more kinds of the hygroscopic material selected from the group consisting of calcium chloride aqueous solution. Further, the refrigerator according to the present invention is, in claim 6, a refrigerator in which a refrigerant compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are connected by piping, and the refrigerant compressor and the condenser are connected to each other. A cooler capable of absorbing and evaporating the moisture in the outside air is arranged between the two, and the moisture absorbed by the cooler is evaporated by the refrigerant temperature at the outlet side of the refrigerant compressor.

[0009]

The refrigerating machine of the present invention is provided with a refrigerant cooler for evaporating and absorbing the moisture contained in the hygroscopic material or the absorbing liquid by a simple method of bringing the hygroscopic material or the absorbing liquid into contact with the pipe through which the high temperature refrigerant flows. , It is possible to improve the refrigerating performance at start-up or the coefficient of performance.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) A first embodiment in which the present invention is applied to a vapor compression refrigerator is shown in FIGS. As shown in FIG. 2, the vapor compression refrigerator 20 includes a compressor 1, a condenser 2, a liquid receiver 3, an expansion valve 4, an evaporator 5, a cooler 10, and a pipe 9 connecting them. To be done. The refrigerant discharged from the compressor 1 circulates in the refrigeration circuit that reaches the compressor 1 via the condenser 2, the liquid receiver 3, the cooler 10, the expansion valve 4, and the evaporator 5.

As shown in FIG. 1, the cooler 10 includes a pipe 9
It is composed of a fin 11, a hygroscopic material 12, and a breathable member 13. The pipe 9 is made of, for example, aluminum or copper, has a cylindrical shape, and the refrigerant flows in the pipe. Fin 11
Is made of, for example, aluminum or copper and is composed of a plurality of discs coaxial with the pipe 9, and is provided on the outer peripheral edge of the pipe 9 to facilitate heat exchange between the refrigerant flowing through the pipe 9 and the moisture absorbent 12. It is provided in a ring shape.

The fins 11 adjacent to each other in the axial direction of the pipe 9 are
The fins 11 are set so as to be parallel to each other, and the interval between the fins 11 is a constant interval of, for example, about 1 to 5 mm, which does not make it difficult for the moisture absorbent 12 to move in and out of water vapor. Further, the length from the outer peripheral surface of the pipe 9 to the outer peripheral end of the fin 11 is
It is determined from the relationship between the cooling amount required for the cooler 10 and the filling amount of the hygroscopic material 12, and is, for example, about 5 to 40 mm.

The hygroscopic material 12 is made of, for example, an adsorbent such as zeolite, silica gel, activated alumina, activated carbon or the like, a hygroscopic polymer resin or the like, and is designed to come into contact with the outer surface of the fin 11 or the outer surface of the pipe or both. Filled in,
It is used to absorb water in the air and replenish it. The filling amount of the hygroscopic material 12 is, for example, about 50 to 200 g when silica gel is used for a car air conditioner. Also,
When silica gel is used as the hygroscopic material 12, the particle size of silica gel is, for example, a particle size of 10 μm or more, which does not make it difficult for water vapor to flow in and out.

The breathable member 13 is made of, for example, cotton, chemical fiber, or metal that allows water vapor to easily pass through without resistance, and is a moisture absorbent filled from the outer peripheral surface of the pipe 9 to the vicinity of the outer peripheral edge of the fin 11. 12 and the fin 11 are wrapped and fixed from the outside. Therefore, the breathable member 13 may have any shape as long as the hygroscopic material 12 does not fall off. For example, a tubular cloth, a tubular net, or a molding made of ceramic, sintered metal, or foam metal with good air permeability. Members may be used.

The length of the cooler 10 with respect to the axial direction of the pipe 9 is determined by the relationship between the cooling amount required for the cooler 10 and the filling amount of the hygroscopic material 12, and when used for a car air conditioner, for example, about 50 mm. Is. When assembling, the pipe 9 is connected to the fins 1 so that the plurality of fins 11 are parallel to each other.
1, the pipe 9 and the fins 11 are brazed together, and a tubular shape is formed while filling the hygroscopic material 12 so as to contact the surface of the fins 11 from the outer peripheral surface of the pipes 9 to the vicinity of the outer peripheral edge of the fins 11. The breathable member 13 wraps and fixes the moisture absorbent 12 and the fin 11 from the outside. The breathable member 13 is a moisture absorbent material 12.
Is fixed by adhering or caulking the end portion 13a to the pipe 9 to the extent that does not leak out.

The operation of the refrigerant circuit of the vapor compression refrigerator 20 will be described along the flow of the refrigerant. At the time of initial start-up, a low-pressure gas refrigerant having a temperature close to the outside air temperature is adiabatically compressed by the compressor 1 and changed into a high-temperature high-pressure gas, which is then sent to the condenser 2 to radiate heat to the outside, for example, a high temperature of about 50 ° C. Become a high-pressure liquid. After that, the refrigerant of the high-temperature high-pressure liquid is temporarily stored in the liquid receiver 3 and then sent to the cooler 10, and the cooler 10 causes the hygroscopic material 12 to flow.
The refrigerant is cooled and becomes a high temperature liquid at a low temperature from the receiver outlet until most of the water replenished by is vaporized as water vapor. Further, the refrigerant is sent to the expansion valve 4, and a part of the refrigerant is atomized by the expansion valve 4 to further lower the temperature, for example, change to a low temperature low pressure gas-liquid two-phase state of about 0 ° C., and then the evaporator. 5, the heat is absorbed from the outside to become a low-temperature low-pressure gas, which is again sent to the compressor 1 and circulated. Due to the endothermic action of the evaporator 5 due to the circulation of the refrigerant, the air flowing through the evaporator 5 is cooled.

During steady operation, most of the moisture replenished by the absorbent material 12 of the cooler 10 becomes steam and vaporization is completed, so that the refrigerant circuit of the vapor compression refrigerator 20 is operated by the cooler 10. The same operation as when not added is performed. Next, based on the operation of the vapor compression refrigerator 20, the cooler 10
The operation of will be described.

Immediately after the vapor compression refrigerator 20 is started, the refrigerant of the high-temperature high-pressure liquid passes through the pipe 9 of the cooler 10, so that the pipe 9 of the cooler 10, the fins 11 and these are fixed so as to be in contact with or capable of exchanging heat. The moisture absorbent 12 is heated. At this time, the hygroscopic material 12 made of, for example, silica gel or activated alumina having a hygroscopic property as shown in FIG.
Indicates that the equilibrium moisture absorption amount gradually decreases from the point A on the curve 15 shown by the solid line to the point B as the temperature of the hygroscopic material 12 rises, so that the replenished water is vaporized and the breathable member 13 To start releasing water vapor to the outside. At the same time, the hygroscopic material 12 removes latent heat for vaporizing water from the surfaces of the pipe 9 and the fins 11 in contact therewith, so that the pipe 9
The fins 11 are cooled, and the refrigerant passing through the pipe 9 is also cooled. As a result, the refrigerant of the high-temperature high-pressure liquid discharged from the liquid receiver 3 promotes heat dissipation by the cooler 10 and improves the refrigeration performance or the coefficient of performance of the vapor compression refrigerator 20. This operation is continued until the moisture absorbing material 12 vaporizes all the water that has been replenished as water vapor and is discharged to the outside through the breathable member 13. After the moisture is released in the cooler 10, the cooling effect does not occur, so the vapor compression refrigerator 20
Is the same refrigerating performance or coefficient of performance as a refrigerator to which the cooler 10 is not added.

After the vapor compression refrigerator 20 is stopped, the temperature of the high-temperature and high-pressure liquid refrigerant is lowered to the ambient temperature due to natural heat radiation and the like, so that the piping 9, the fins 11 and the hygroscopic material 12 contacting these are provided. Similarly, the temperature drops to the outside temperature. As a result, the hygroscopic material 12 made of, for example, silica gel or activated alumina having the hygroscopic property as shown in FIG. 3 has the equilibrium hygroscopic amount from the point B on the curve 15 indicated by the solid line as the temperature of the hygroscopic material 12 decreases. Since it gradually increases toward point A, it spontaneously absorbs water vapor in the outside air to replenish water. Therefore, the maintenance worker does not need to supply water to the cooler 10.

From the above, the cooler 10 added between the liquid receiver 3 and the expansion valve 4 takes latent heat from the surfaces of the pipes 9 and the fins 11 to perform heat exchange, so that the cooling system shown in the conventional example is used. It is possible to remarkably improve the heat exchange efficiency as compared with the cooling heat exchanger 6 that performs heat exchange by heat, and promotes heat dissipation of the high-temperature refrigerant at the time of starting the vapor compression refrigerator 20 to improve the refrigerating performance at the time of starting. Or the coefficient of performance can be improved.

In the present invention, the shape of the fin is not limited to a circular plate, and may be a rectangular shape, a polygonal shape, or any other complicated shape as long as heat exchange between the refrigerant flowing through the pipe and the hygroscopic material is possible. Further, the method of fixing the pipe and the fin may be a method of press-fitting the pipe into the fin, a method of expanding the pipe after the pipe is inserted into the fin, and crimping. Furthermore, a pipe in which the pipe and the fin are integrally formed may be used.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
Shown in. The vapor compression refrigerator according to the second embodiment differs from the vapor compression refrigerator 20 according to the first embodiment in that a cooler 10 is added between the compressor 1 and the condenser 2. As shown in FIG. 4, the refrigerant circuit of the vapor compression refrigerator 30 includes a compressor 1, a condenser 2, a liquid receiver 3, an expansion valve 4, an evaporator 5, and a cooler 10.
The refrigerant flowing through the refrigerant circuit is compressed from the compressor 1 via the cooler 10, the condenser 2, the liquid receiver 3, the expansion valve 4, and the evaporator 5. Machine 1
Circulate in the refrigeration circuit leading to.

The operation of the refrigerant circuit of the vapor compression refrigerator 30 will be described along the flow of the refrigerant. At the time of start-up, the low-pressure gas refrigerant having a temperature close to the outside air temperature is adiabatically compressed by the compressor 1 and changed into a high-temperature and high-pressure gas, and then sent to the cooler 10 to cool the cooler 1.
By 0, the refrigerant is cooled and becomes a high-pressure gas at a temperature lower than that of the gas at the compressor outlet until most of the moisture replenished by the hygroscopic material 12 is vaporized as water vapor. After that, this high-pressure gas refrigerant is sent to the condenser 2 and radiates heat to the outside to become a high-pressure liquid. Furthermore, after the refrigerant is temporarily stored in the receiver 3,
It is sent to the expansion valve 4, and after being changed to a low-temperature low-pressure gas-liquid two-phase state of, for example, about 0 ° C. by the expansion valve 4, it is sent to the evaporator 5 and absorbs heat from the outside to become a low-temperature low-pressure gas and is sent to the compressor 1 again. Be circulated. Due to the endothermic action of the evaporator 5 due to the circulation of the refrigerant, the air flowing through the evaporator 5 is cooled.

During steady operation, as in the first embodiment, the refrigerant circuit of the vapor compression refrigerator 30 operates in the same manner as when the cooler 10 is not added. According to this second embodiment, the cooler 10 added between the compressor 1 and the condenser 2
However, since the condenser 2 plays an auxiliary role at the time of starting the vapor compression refrigerator 30 and promotes the heat dissipation of the high-temperature refrigerant, the refrigerating performance or the coefficient of performance at the time of starting can be improved.

(Third Embodiment) FIG. 5 shows a third embodiment of the present invention.
And shown in FIG. In the third embodiment, the moisture absorbent is adhered to the heat dissipation surface of the condenser, so that the cooler 10 of the second embodiment is used.
The difference from the second embodiment is that the condenser has the function of. As shown in FIGS. 5 and 6, the condenser 40 includes a tube 4
1, a corrugated fin 42, and a hygroscopic material 43.

The tube 41 has a shape in which a tubular tube formed in a quadrangular shape having a rectangular transverse shape so as to withstand high pressure is diffracted back in a U shape on the same plane. Tube 4
A coolant flows inside the unit 1, and corrugated fins 42 are provided between adjacent tubes 41 that are folded back in a U shape. The corrugated fin 42 is composed of a corrugated thin plate adapted to the interval between the tubes 41 folded back in a U shape,
The corrugated peaks and valleys are fixed by brazing or the like so as to come into contact with the tube 41. Also, the corrugated fin 42
A moisture absorbent material 43 having an extremely small particle size is adhered to the surface of the above in order to suppress the increase of ventilation resistance as much as possible. In this case, the moisture absorbent 4
No breathable member is required as 3 is glued and fixed.

According to this third embodiment, this condenser 40
When the condenser 40 is used in the refrigeration circuit, as in the case where the cooler 10 of the second embodiment is added, the moisture absorbing material 43 adhered to the heat exchanger 40 removes latent heat from the surface of the condenser 40 to perform heat exchange. It is possible to promote the heat dissipation of the high temperature refrigerant at the time of starting the compression type refrigerator and improve the refrigerating performance or the coefficient of performance at the time of starting.

(Fourth Embodiment) A fourth embodiment of the present invention is shown in FIG.
And shown in FIG. The cooler according to the fourth embodiment is different from the cooler 10 according to the first embodiment in that fins are formed in a beard shape and a hygroscopic material is bonded to the surfaces of the fins having a beard shape.
As shown in FIGS. 7 and 8, the cooler 50 includes the pipe 9, the spiral fin 51, and the moisture absorbent 12.

The spiral fin 51 is composed of a strip-shaped base portion 51 which comes into contact with the pipe 9, and a whisker-shaped whisker portion 52 which extends from the surface of the base portion 51 to the outside in the radial direction of the pipe 9, and is spirally formed on the outer peripheral surface of the pipe 9. It is wound around and fixed. Hygroscopic material 12
Is bonded to the surface of the pipe 9 and the surface of the whiskers 52 of the spiral fin 51.

According to the fourth embodiment, the hygroscopic material 12 adhered to the surfaces of the pipe 9 and the whiskers 52 of the spiral fin 51 removes latent heat from the surfaces of the pipe 9 and the spiral fin 51 for heat exchange. When the cooler 50 is used in the refrigeration circuit, as in the case where the cooler 10 of the first embodiment is added, the heat dissipation of the high temperature refrigerant is promoted at the time of starting the vapor compression refrigerator, and the refrigeration performance or the coefficient of performance at the time of starting. Can be improved. The same effect can be obtained by using skived fins instead of the spiral fins.

(Fifth Embodiment) FIG. 9 shows a fifth embodiment of the present invention.
Shown in. The cooler according to the fifth embodiment is different from the cooler 10 according to the first embodiment in that a liquid absorbing liquid is used instead of the moisture absorbent 12 and a liquid tank for storing the absorbing liquid is provided. As shown in FIG. 9, the cooler 60 includes a pipe 9, fins 11, a liquid tank 61, an absorbing liquid 62, and a breathable member 63.

The pipe 9 is a fin 11 similar to that of the first embodiment.
, And penetrates from one side surface of the liquid tank 61 to the other side surface. The liquid tank 61 is composed of a container having an opening at the top,
The fins 11 of the pipe 9 exchange heat with the absorbing liquid 62 stored in the liquid tank 61. The absorbing liquid 62 is made of, for example, an aqueous solution of lithium bromide or an aqueous solution of calcium chloride, and the absorbing liquid 62 is used until the entire fin 11 is immersed in the absorbing liquid 62.
Are stored in the liquid tank 61.

The air-permeable member 63 prevents dust and the like in the air from flowing into the liquid tank 6.
In order to prevent the liquid from entering the container 1, it is provided so as to cover the entire opening of the liquid tank 61. According to the fifth embodiment, the absorbing liquid 62 stored in the liquid tank 61 removes latent heat from the surfaces of the fins 11 to perform heat exchange. Therefore, when the cooler 60 is used in the refrigeration circuit, the cooling of the first embodiment is performed. Similar to the case where the vessel 10 is added, it is possible to promote the heat dissipation of the high temperature refrigerant at the time of starting the vapor compression refrigerator and improve the refrigerating performance or the coefficient of performance at the time of starting.

[0034]

According to the refrigerator of the present invention, by using in the refrigeration circuit a cooler capable of cooling the refrigerant by exchanging heat with the high temperature refrigerant flowing in the pipe,
The refrigerating performance or the coefficient of performance can be improved during the period when water remains in the cooler, and the structural volume, weight, and cost can be reduced.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a cooler according to a first exemplary embodiment of the present invention.

FIG. 2 is a circuit diagram showing a refrigerant circuit of the vapor compression refrigerator according to the first embodiment of the present invention.

FIG. 3 is a hygroscopic characteristic diagram showing an equilibrium hygroscopic amount of a hygroscopic material of a cooler according to a first embodiment of the present invention with respect to a hygroscopic material temperature.

FIG. 4 is a circuit diagram showing a refrigerant circuit of a refrigerator according to a second embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a condenser to which a hygroscopic material according to a third embodiment of the present invention is adhered.

FIG. 6 is an enlarged view of the inside of the circle shown in FIG. 5 of the third embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of a cooler according to a fourth embodiment of the present invention.

FIG. 8 is an enlarged sectional view in a circle shown in FIG. 7 of a fourth embodiment of the present invention.

FIG. 9 is a schematic configuration diagram of a cooler according to a fifth embodiment of the present invention.

FIG. 10 is a circuit diagram showing a refrigerant circuit of a conventional refrigerator.

[Explanation of symbols]

1 compressor (refrigerant compressor) 2 condenser 3 liquid receiver 4 expansion valve 5 evaporator 9 piping 10 Cooler 11 fins 12 Hygroscopic material 13 Breathable material 20 Vapor compression refrigerator 40 condenser 41 tubes 42 Corrugated fin (fin) 43 Hygroscopic material 62 Absorbing liquid (hygroscopic material)

Claims (7)

(57) [Claims] 1. A refrigerator in which a refrigerant compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are connected by piping, and moisture absorption of moisture in the outside air is provided between the liquid receiver and the decompression device. And a cooler capable of performing evaporation, and the moisture absorbed in the cooler is evaporated by the refrigerant temperature at the outlet side of the receiver. 2. The cooler includes a pipe through which a refrigerant flows,
The refrigerator according to claim 1, further comprising: a fin fixed to an outer peripheral surface of the pipe and extending outward in a radial direction; and a hygroscopic material contacting at least an outer surface of the fin and capable of absorbing and evaporating moisture. . 3. The refrigerator according to claim 2, wherein the hygroscopic material is adhered to an outer surface of the fin, an outer surface of the pipe, or both. 4. The refrigerator according to claim 2, wherein the hygroscopic material is filled between the fin or the pipe and an air permeable member that covers the fin or the pipe. 5. The hygroscopic material is one or more kinds selected from the group consisting of zeolite, silica gel, activated alumina, activated carbon, hygroscopic polymer resin, aqueous solution of lithium bromide, and aqueous solution of calcium chloride. 5. The refrigerator according to claim 2, 3 or 4. 6. A refrigerating machine in which a refrigerant compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are connected by piping, and moisture absorption of moisture in the outside air is provided between the refrigerant compressor and the condenser. And a cooler capable of performing evaporation, and the moisture absorbed in the cooler is evaporated by the refrigerant temperature at the outlet side of the refrigerant compressor. 7. A refrigerant compressor, a condenser, a receiver, a decompression device, an evaporator a refrigerator connected by a pipe, arranged hygroscopic material to the heat exchange surface of the condenser, the moisture absorbing material refrigerator according to claim Rukoto evaporate moisture absorbed from the outside air.