JP2002122365A - Refrigerating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerating system which is abundant in stability and economical efficiency by raising the compression efficiency as well as downsizing a heat-exchanging means for condensation. SOLUTION: This is a refrigerating system where a freezing cycle for getting cold for freezing and cooling is made of a compressor 1, a heat converting means 2 having a function of converting the heat energy that refrigerant gas possesses into kinetic energy and besides changing the gas-liquid phase in the process of that conversion, a decompression means 3, and a cooler 4. The heat converting means 2 is constituted of a single group of a thermal conversion unit consisting of a series-connected pipe line composed of the first-stage coil thin pipe line 5 which is made by winding a small-diameter heat conductive pipe into coil form, a large-diameter short pipe 7 which has a wider sectional area for circulation as compared with the above heat conductive pipe, and the second-stage coil thin pipe line 6 of structure analogous to the first-stage coil thin pipe line 5, or a plurality of groups where those thermal conversion units are connected in parallel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration system capable of reducing the size of heat exchange means for condensation. Note that the refrigeration system referred to in this specification is a refrigeration apparatus, a refrigeration apparatus, a cooling apparatus, etc., a refrigerant pressure of a condensable refrigerant gas such as a CFC refrigerant,
A cooling system in various devices that performs cooling of an object to be cooled in the course of a cycle involving changes in temperature and phase.

[0002]

2. Description of the Related Art Although a conventional refrigeration system is not shown, a condensable gas refrigerant such as a Freon refrigerant sealed in a refrigeration cycle is converted into a high-temperature and high-pressure gas refrigerant by a compressor. After heat exchange with air (or cooling water) to condense and liquefy, the liquid is phase-converted to a liquid close to normal temperature, and then decompressed and expanded by a decompressor such as an expansion valve to form a low-temperature low-pressure liquid refrigerant. Is sent to a cooler (evaporator) to exchange heat with air or cooling water to evaporate it into a low-temperature, low-pressure gas refrigerant, while cooling the air or cooling water and using it as a cold heat source for freezing and cooling. The low-temperature and low-pressure gas refrigerant is returned to the compressor. In this case, it is well known that a cross fin type heat exchanger is exclusively used for air, while a shell type heat exchanger is exclusively used for cooling water.

In such a conventional refrigeration system, the condenser acting as the heat source side heat exchanger has to be of a larger structure than the cooler acting as the utilization side heat exchanger. Therefore, various studies have been made to reduce the size of the condenser in order to reduce the size of the equipment.However, the heat exchange area required for condensing and liquefying in the current refrigeration system depends on the type of refrigerant used. The value is determined from the design, and it is technically difficult to greatly reduce the value, and a large condenser is still used.

A conventional example of a vehicle air conditioner (cooling air conditioner) will be further described. In most cases, an air-cooled condenser having a large heat exchange area is installed in a space in front of a radiator. In addition to significantly lowering the capacity, fuel was also consumed excessively, which spurred the emission of carbon dioxide.Furthermore, when the outside air temperature was high in midsummer, the amount of heat exchange in the condenser was insufficient, and the air conditioner was stopped due to high pressure cut. There were also frequent problems.

[0005] Further, in conventional industrial air conditioners and coolers, the installation space for both air-cooled and water-cooled systems, especially the outdoor installation space, is large. Not only was it bulky, but the construction period was long and economic disadvantages were inevitable.

[0006]

SUMMARY OF THE INVENTION In order to solve the problems of the conventional refrigeration / cooling system,
The present applicant previously proposed a novel refrigeration system capable of reducing the size of a condensing heat exchange device in Japanese Patent No. 2835325, and thereby promoted a reduction in the cost of the device and energy saving to promote the global environment. The present invention aims to further enhance the value as a practical device by further simplifying the refrigeration system, Accordingly, it is an object of the present invention to provide a refrigeration system which can reduce the size of the heat exchange means for condensation and increase the compression efficiency, thereby enhancing stability and economy.

[0007]

The present invention has the following configuration to achieve the above object. That is, the invention of claim 1 of the present invention converts a condensable refrigerant gas such as chlorofluorocarbon discharged from the compressor 1 with an increased pressure and temperature into heat energy held by the refrigerant gas into kinetic energy and After being supplied to the heat conversion means 2 having a function of changing the gas-liquid phase in the conversion process to be a refrigerant liquid, the refrigerant liquid is sent to a pressure reducing means 3 such as an expansion valve to be decompressed and expanded. And the latent heat of evaporation is exchanged with the air or the water to be cooled, thereby evaporating the refrigerant. The low-pressure condensable gas refrigerant thus vaporized is sucked by the compressor 1 and cooled by the cooler 4. A refrigeration system in which a refrigeration cycle for obtaining cold heat is formed, wherein the heat conversion means 2 is wider than the first-stage coil thin-tube path 5 formed by coiling a small-diameter heat transfer tube and the heat transfer tube. Large diameter with flow cross section A single heat conversion unit composed of a series connection of a short tube 7 and a second-stage coil thin line 6 having a structure similar to the first-stage coil thin line 5, or a plurality of heat conversion units connected in parallel A refrigeration system characterized by being constituted by a base.

[0008] The invention of claim 2 of the present invention provides:
The refrigeration system according to claim 1, wherein the first-stage coil narrow tube 5 and the second-stage coil narrow tube 6 are formed in a left-hand coil winding with reference to the flow direction of the refrigerant in the tubes. .

Further, the invention of claim 3 of the present invention provides:
In the refrigeration system according to the second aspect, a cooling fan 8 is attached to at least the first-stage coil thin line 5 of the first-stage coil thin line 5 and the second-stage coil thin line 6,
When the temperature of the refrigerant gas discharged from the compressor 1 is equal to or higher than a predetermined value, the fan 8 performs a blowing operation.

According to the present invention, the mode of heat exchange in the condensing process in the refrigeration system is basically such that the rotary flow is converted to convert the heat energy held in the condensable gas refrigerant into kinetic energy. Focusing on the phenomenon that a significant gas / liquid phase change occurs in the process of achieving the accompanying speed-up action (although a slight pressure reduction action is also performed at the same time), and applying this to the condensation step of the refrigeration cycle, The feature of the present invention resides in that most of the heat balance required for liquefaction is obtained from the circulating refrigerant itself.

That is, the condensing process in the conventional refrigeration system is a system in which a high-temperature and high-pressure condensable gas refrigerant discharged from a compressor is cooled by outside air or water and condensed and liquefied. In this method, a condensing method is adopted that does not require the use of a large amount of cooling fluid such as air or water as a cooling heat source for condensation and liquefaction, and allows the condensable gas refrigerant itself to perform a heat balance. That is, the high temperature and high pressure condensable gas refrigerant discharged from the compressor is
By flowing the gas fluid flowing inside to heat conversion means (heat energy / kinetic energy conversion means) capable of converting the heat energy to kinetic energy by increasing the flow velocity under a rotating flow, The fact that the temperature can be changed and liquefied in the flowing refrigerant is an important feature of the present invention.

By adopting the above-described novel system, the present invention can be downsized to a tenth of the installation space ratio as compared with the conventional condenser under the same refrigeration and cooling capacity. In other words, it is possible to draw out about several times the condensing capacity with the same external dimensions, thereby reducing the equipment cost and energy saving in the refrigeration system.

[0013] The present invention also adopts a condensed liquefaction system using heat conversion means for obtaining a heat balance for the refrigerant itself.
Low-pressure condensable gas that can reduce the discharge pressure of the compressor significantly compared to the conventional method, and as a result, can secure a stable amount without increasing the high-low pressure difference in the compressor The suction of the refrigerant is performed smoothly, so that the compressor can maintain a stable drawing pressure in a low pressure range, the compression efficiency increases, the coefficient of performance improves, and the load on the drive motor increases. Thus, a refrigeration system with a high operating economy can be provided.

Further, according to the second aspect of the present invention, since the speed increasing action accompanied by the rotational flow in the heat conversion means is more effectively exhibited, the heat conversion efficiency is increased, the compression efficiency is improved, and energy saving is achieved. Can be further improved. According to the third aspect of the present invention, the compressor 1 is prevented from being overheated, and is excellent in safety.

The heat conversion means, which is a structural feature of the present invention, applies pressure energy and heat energy to the condensable refrigerant gas discharged from the compressor, that is, during the compression stroke of the compressor. For the condensable refrigerant gas whose pressure and temperature have risen by being converted almost all of the thermal energy into kinetic energy,
In addition, it has a function of effectively condensing a gas component in this conversion process. The first-stage coil narrow tube 5 and the second-stage coil narrow tube 6 convert the refrigerant flowing therein into kinetic energy. To increase the flow velocity and thereby promote the condensation and liquefaction of the gas on the downstream side. On the other hand, in the large-diameter short pipe 7, the first-stage coil thin tube is used. Gas derived from Road 5
A function of decelerating the liquid-mixed flash refrigerant by the diffusion flow and relaxing the rotational flow, and having a function of further improving the rotation speed-up function and the condensing / liquefaction function in the subsequent second-stage coil narrow pipe 6. Thus, the refrigerant gas can be reliably condensed and liquefied by the heat conversion means without relying entirely on the heat exchange action of the cooling fluid such as air and water as in the conventional case. This has been sufficiently confirmed based on the results of repeated studies and experiments by the present inventors, and will be made clear by the following description of embodiments of the invention.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a schematic circuit diagram of a refrigeration system according to an embodiment of the present invention. FIG. 2 is an enlarged perspective view of a main part of the heat conversion means 2 in the refrigeration system shown in FIG.

The refrigeration system shown in FIG.
A heat conversion unit 2, an expansion valve as a decompression unit 3, and a cooler 4 are provided as element devices, and these devices are connected to a suction pipe 11,
By connecting the refrigerant pipes of the discharge pipe 12, the high-pressure liquid pipe 13, and the low-pressure liquid pipe 14 as a cyclic loop circuit, an apparatus for refrigeration / cooling in which Freon is filled as a circulating refrigerant in the loop circuit is configured. Is done.

The compressor 1, the expansion valve 3, and the cooler 4 have basically the same structure and function as those used in the conventional refrigeration / cooling apparatus, and therefore detailed description thereof is omitted here. An embodiment of the heat conversion means 2 which is a constituent element of the present invention will be described below.

The heat conversion means 2 comprises a first-stage coil thin tube 5 formed by winding a small-diameter heat transfer tube, for example, a copper thin tube in a left coil winding with reference to the flow direction of the refrigerant in the tube. A short tube 7 made of, for example, a copper tube having a large cross-sectional area larger than that of the heat transfer tube and made of, for example, a copper tube, and a second-stage coil thin tube 6 having a structure similar to the first-stage coil narrow tube 5 are formed. A series connection pipe formed by being connected in series from the upper side to the lower side based on the flowing direction of the flowing Freon is provided as a heat conversion unit, and a single unit of the heat conversion unit or the heat conversion unit The first-stage coil narrow tube 5 and the second-stage coil narrow tube 6 have a predetermined diameter in the range of 1.2 to 3.2 mmφ. 1.0-2.
A copper thin tube having a predetermined length in the range of 0 m and a coil diameter of 20 to 30
It consists of a coil tube formed by winding a coil in a spiral shape having a predetermined diameter in the range of mmφ. In the illustrated embodiment, the first-stage coil thin tube 5 is housed in an elongated tubular casing 9 shown by a chain line in FIG.
The air is blown into the casing 9 by the attached fan 8 so that the casing 9 can be forcibly cooled. According to the present invention, the casing 9 is provided so as to accommodate at least the first-stage coil narrow tube 5 of the first-stage coil narrow tube 5 and the second-stage coil narrow tube 6.

On the other hand, the large-diameter short pipe 7 has a diameter of 9.3, for example.
A copper short tube of 6 mm (3/8 inch) and a length of several tens of mm is used, and both ends are finished to a small diameter by drawing or the like, and the first-stage coil thin tube as described above is provided at the inflow side end. The outflow-side end of the passage 5 is connected, and the inflow-side end of the second-stage coiled capillary passage 6 is connected to the outflow-side end.

The first-stage coil thin tube 3 and the second-stage coil narrow tube 4 may have the same structure, and may have different tube lengths and tube diameters. The coil winding direction may be the same, or one may be left-handed and the other right-handed, but left-handed winding is preferred in terms of the efficiency of conversion to kinetic energy.

In the heat conversion means 2, the inflow side end of the first-stage coil narrow pipe 5 is connected to the discharge port 10 of the compressor 1 via the discharge pipe 12, and the second-stage coil narrow pipe 6 The outflow end is connected to the inlet of the expansion valve 3 via the high-pressure liquid pipe 13. The outlet of the expansion valve 3 and the inflow end of the cooler 4 are connected by a low-pressure liquid pipe 14, and the outflow end of the cooler 4 and the suction port of the compressor 1 are connected by a suction pipe 11. .

In the illustrated embodiment, the high-pressure liquid pipe 13 for guiding the liquid refrigerant condensed and liquefied by the heat conversion means 2 to the expansion valve 3 is provided by connecting the helical heat transfer pipe 13A to a part or the whole of the pipe. Have. The helical heat transfer tube 13A is used to positively generate a rotational flow in the liquid refrigerant flowing in the tube, to increase the flow speed while increasing the distance, to promote the supercooling effect, and to slightly lower the refrigerant pressure. It is provided.

By providing such a high-pressure liquid pipe 13, the pressure at the inlet of the expansion valve 3 is reduced, and a large amount of liquid refrigerant is sent to the expansion valve 3 at a lower pressure and a lower temperature, and the liquid seal at the inlet is formed. Therefore, the expansion and reduction operation of the expansion valve 3 can be performed smoothly and stably.

In FIG. 1, reference numeral 15 denotes a fan for the cooler attached to the cooler 4, reference numeral 16 denotes a temperature-sensitive cylinder, and the temperature-sensitive cylinder 16 discharges gas to detect the temperature of the gas discharged from the compressor 1. A blow operation output is output to the fan 8 when the temperature of the Freon gas discharged from the compressor 1 is equal to or higher than a predetermined value.

Next, the operation of the refrigeration system will be described. Using Freon R-12 as a refrigerant, a reciprocating type compressor with an output of 200 Watt was used as the compressor 1, and a 1.5 mm long copper tube with an inner diameter of 1.5 mmφ and a coil diameter of 25 mmφ was used as the heat conversion means 2. A first-stage coil thin tube 3 formed by spirally winding a left coil, a second-stage coil thin tube formed by spirally winding a 1.2 mm long copper tube having an inner diameter of 1.5 mmφ and a left coil of 25 mmφ. By using the path 4 and a large-diameter short pipe 5 formed of a copper short pipe having a diameter of 9.36 mm and a length of 10 mm, cooling is performed by a cooler 4 composed of a cross-fin heat exchanger equipped with a fan 15 for a cooler. The refrigeration operation to be performed will be described.

After suction by the operation of the compressor 1, the compressed and discharged Freon gas whose pressure and temperature have risen is sent to the heat conversion means 2, where the heat energy applied in the compressor 1 is accompanied by a rotational flow. The flow velocity is converted to kinetic energy by the increased flow velocity, and the fluorocarbon gas is efficiently condensed and liquefied based on the heat balance of the fluorocarbon itself at that time. The condensed and liquefied high-pressure liquid refrigerant is supercooled and reduced in pressure while passing through the helical heat transfer tube 13A of the high-pressure liquid tube 13, and becomes a medium-pressure liquid refrigerant. This medium pressure liquid refrigerant reaches the expansion valve 3,
After being decompressed and expanded to become a low-pressure low-temperature liquid refrigerant, the refrigerant is sent to the cooler 4 where it evaporates by exchanging latent heat of vapor with air generated by the fan 15. The low-pressure gas refrigerant evaporated and vaporized by the cooler 4 passes through the suction pipe 11 and is sucked into the compressor 1 to form the refrigeration cycle as described above. In this refrigerating cycle, the air blown by the fan 15 is cooled by the cooler 4, so that a cooling heat source is obtained.

In the freezing operation, when the temperature of the discharge pipe 12 reaches a set value, for example, 60 ° C., the fan 8 is operated to blow air, while the pressure or temperature of the suction pipe 11 becomes lower than the set value. The operation of the compressor 1 is stopped.

[0029]

The present invention is embodied in the form described above and has the following effects. That is,
Focusing on the fact that a large heat exchange area for condensing was the main cause of the increase in size of the refrigeration system, the device of the present invention condensed based on the proposal of a new refrigeration cycle with heat conversion means as a component. The heat exchange area can be dramatically reduced, and as a result, the structure of the refrigeration system can be made compact, excess energy consumption can be reduced, and installation space can be reduced. I can make it work. According to the second aspect of the present invention, the coefficient of performance is improved by improving the heat conversion performance of the heat conversion means and the compression efficiency of the compressor, thereby increasing the load on the drive source such as the engine and the motor. And the driving economy is remarkably improved. According to the present invention, the emission of carbon dioxide during the refrigeration operation can be significantly reduced, which can play a great role in preserving the global environment. Furthermore, according to the third aspect of the present invention, the compressor 1 is prevented from being overheated and is excellent in safety.

[Brief description of the drawings]

FIG. 1 is a circuit diagram schematically showing a refrigeration system according to an embodiment of the present invention.

FIG. 2 is a heat conversion means 2 in the refrigeration system shown in FIG.
It is an expansion perspective view of the principal part of.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Compressor 2 ... Heat conversion means 3
... decompression means 4 ... cooler 5 ... first-stage coil narrow pipe 6
… Second-stage coil narrow pipe 7… Large diameter short pipe 8… Fan 9
... Casing 10 ... Discharge port 11 ... Suction pipe 1
2: discharge pipe 13: high-pressure liquid pipe 13A: spiral heat transfer pipe 1
4: Low pressure liquid pipe 15: Cooler fan

Claims (3)

[Claims] 1. A method for converting condensable refrigerant gas, such as chlorofluorocarbon, discharged from a compressor 1 and having an increased pressure and temperature into thermal energy possessed by the refrigerant gas into kinetic energy, and in the process of gas / liquid conversion, After being supplied to the heat conversion means 2 having a function to change the phase and made into a refrigerant liquid, this refrigerant liquid is sent to a pressure reducing means 3 such as an expansion valve to be decompressed and expanded, and then sent to a cooler 4 to be air or cooled. A refrigeration cycle is provided in which the latent heat of vaporization is exchanged with water to evaporate the refrigerant, and the vaporized low-pressure condensable gas refrigerant is sucked by the compressor 1 and the cooler 4 obtains cooling heat for freezing and cooling. The refrigeration system thus formed, wherein the heat conversion means 2 comprises a first-stage coiled narrow tube path 5 formed by coiling a small-diameter heat transfer tube.
And a large-diameter short pipe 7 having a wider cross-sectional area than the heat transfer pipe.
And a single unit of a heat conversion unit composed of a series connection line of a second stage coil thin line 6 having a structure similar to that of the first stage coil thin line 5 or a plurality of units in which the heat conversion units are connected in parallel. A refrigeration system characterized by being performed. 2. The refrigeration system according to claim 1, wherein the first-stage coil narrow tube 5 and the second-stage coil narrow tube 6 are formed with a left coil winding based on a flow direction of the refrigerant in the lines. 3. A cooling fan 8 is attached to at least the first-stage coil thin line 5 of the first-stage coil thin line 5 and the second-stage coil thin line 6, and the condensate discharged from the compressor 1 is provided. The refrigeration system according to claim 2, wherein the fan (8) performs a blowing operation when the temperature of the reactive refrigerant gas is equal to or higher than a predetermined value.