JPS6157678A - Refrigerant and refrigerator - Google Patents

Abstract

PURPOSE:To provide a refrigerant capable of lowering the ejecting gas temperature of a compressor, and suitable for automobile or domestic cooler or refrigerator, by mixing a main refrigerant with an assistant refrigerant having higher boiling point than the main refrigerant. CONSTITUTION:A refrigerant for refrigeration cycle is produced by mixing a main refrigerant such as flon-12, etc. with an assistant refrigerant such as flon- 113. The amount of the assistant refrigerant is <=10wt% in liquid state. EFFECT:The assistant refrigerant is evaporated by the compressor 1 connected with an engine via an electromagnetic clutch 1a, to effect the lowering of the ejecting gas temperature, and the prevention of the seizing of the compressor. Both main refrigerant and assistant refrigerant are liquefied in the condenser 2, and transferred through the liquid reservior 3 and the expansion valve 4. Since only the main refrigerant is evaporated in the evaporator 5 and the assistant refrigerant is passed in liquid state, the fluidity of the refrigerator oil can be increased, and the heat-exchange efficiency can be improved.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an evaporative refrigerator that has a relatively high evaporation temperature, such as an automobile or household cooling device or a refrigerator, and particularly relates to an evaporative refrigerator that is enclosed in a refrigeration cycle. This relates to the improvement of refrigerants.

(Prior art) Conventionally, in this type of refrigerator, Freon-12 is generally used.
Single-component refrigerants such as

However, as shown in Japanese Patent Publication No. 54-37328, it is known that a refrigerant can be constructed by combining two or more components, but this is an azeotropic mixture, which means that components with different boiling points are combined. Technical ideas are not seen in the past. .

(Problem to be solved by the invention) However, as mentioned above, conventionally, the boiling point of the refrigerant is unique and all the refrigerant evaporates in the evaporator, so the refrigerant is sucked into the compressor. The refrigerant is superheated vapor, which is compressed in a compressor, so the temperature of the discharged gas tends to be high, especially when the cooling load and compressor rotational speed fluctuate greatly, such as in automobile cooling systems. When a compressor with good volumetric efficiency, such as a rotary compressor, is used, abnormally high temperatures may occur. If the temperature of the discharged gas were to rise in this way, there was a risk that not only would the rubber hoses for connection and the gaskets for sealing be damaged, but the pressure I1 machine would seize up.

Therefore, an object of the present invention is to lower the temperature of the gas discharged from the compressor by using a refrigerant that is a combination of two or more components with different boiling points.

(Means for Solving Problems) The most characteristic feature of the present invention is that an auxiliary refrigerant, which has a higher boiling point than the main refrigerant and evaporates in the compressor, is mixed with the main refrigerant in an amount of 10% by weight or less. It is in. This is particularly effective when used in a refrigerator that has a rotary compressor.

(Function) Therefore, the main refrigerant circulates through the refrigeration cycle and is used to cool air, etc. in the same way as in general refrigerators, but the auxiliary refrigerant has a high boiling point and does not evaporate in the evaporator, but in the compressor. Since the refrigerant evaporates endothermically, it absorbs the heat of the main refrigerant as latent heat during compression, lowering the temperature of the discharged gas, thereby achieving the above object.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 2, an automobile cooling system to which the present invention is applied is shown, in which a compressor 1, a condenser 2, a liquid receiver 3, an expansion valve 4, and an evaporator 5 are sequentially connected via piping to form a closed circuit refrigeration cycle. The compressor 1 includes an electromagnetic clutch 1
is connected to a vehicle engine (not shown) via a, and this '1 is driven by connecting and disconnecting a magnetic clutch 1a.
The condenser 2 is controlled to stop, and the condenser 2 is connected to the blower 6.
It is designed to be cooled by the outside air drawn in.

Further, as shown in FIG. 3, for example, the compressor 1 is of a rotary vane type, and side blocks 8a and 8b are fixed to both sides of a cylinder 7 having an elliptical guide surface for compression. A compressor main body 9 is constructed, and this compressor main body 9
A cylindrical rotor 10 is arranged inside. This rotor 1O is firmly connected to a shaft 11 that is pivotally supported by both side blocks 8a and 8b, and a plurality of grooves 12 are formed in the substantially radial direction of the rotor 10, and vanes 13 are installed in each of the grooves 12. It is slidably inserted. The vane 13 rotates with the tip of the vane 13 being guided by the guide surface of the cylinder 7 as the rotor 10 rotates,
A compression chamber 14 surrounded by a pressure wJ machine main body 9, a rotor 10, and a vane 13 changes its volume while moving in the radial direction.

The area around the compressor body 9 is the front cylinder head 1.
5 and the rear shell 16, the pressure machine body 9,
Low pressure chamber 1 consisting of cylinder head 15 and shell 16
7 and a high pressure chamber 18 are appropriately partitioned. The low pressure chamber 17 communicates with the refrigerant port 19 formed in the cylinder head 15, and also communicates with the compression chamber 14 during the suction stroke through a suction hole 20 formed in one side block 8a.
It is becoming familiar to Further, the high pressure chamber 18 communicates with a refrigerant outlet 21 formed in the shell 16, and
It communicates with the compression chamber 14 during the discharge stroke through a discharge hole (not shown) formed in the cylinder 7, and a discharge valve provided in the discharge hole is pushed open during this discharge stroke.

Therefore, when the shaft 11 rotates, the vane 13 rotates along the guide surface of the cylinder 7 as the rotor 10 rotates, and if it is in the suction stroke, the compression chamber 14 communicates with the low pressure chamber 17, and the refrigerant flows into the compression chamber 14. Gas is inhaled and this compression chamber 1
As the volume of refrigerant 4 gradually decreases, the refrigerant is compressed, the discharge valve is pushed open, and the refrigerant is discharged from the discharge hole into the high pressure chamber 18, and then exits from the refrigerant outlet 21 via the high pressure chamber 18.

In such a refrigeration cycle, a refrigerant is sealed together with refrigerating machine oil, and this refrigerant consists of a main refrigerant and an auxiliary refrigerant. The main refrigerant is, for example, Freon-12
(CFz Ct, ), while the auxiliary refrigerant consists of, for example, Freon-113 (CCI□F/CCIFg). This auxiliary refrigerant is not evaporated in the evaporator 5 and is transferred to the compressor 1.
Its boiling point is higher than that of the main refrigerant so that it evaporates at

This auxiliary refrigerant has a liquid state of 10% compared to the main refrigerant.
They are mixed at less than % by weight. The mixing method is, for example,
A liquid auxiliary refrigerant is introduced into the evacuated refrigeration cycle using differential pressure, and then the main refrigerant is introduced.

Alternatively, a mixed state of the main refrigerant and the auxiliary refrigerant may be sealed in a can or the like, and the mixture may be transferred from the can to the refrigeration cycle in a normal manner.

In the above configuration, Freon-12 compressed by compression [1]
The mixed refrigerant of CFC and CFC 113 enters the condenser 2. Here, if the condensation temperature is 60°C, the condensation pressure of Freon-12 is approximately 15.5 kg/cal abs, and that of Freon-113 is 1.53 kg/cal abs, so the auxiliary refrigerant is used in this condenser together with the main refrigerant. 2, it is condensed and liquefied.

Next, this liquefied refrigerant passes through the liquid receiver 3, the expansion valve 4, and enters the evaporator 5. Here, if the evaporation temperature is 0°C, the saturated evaporation pressure of Freon-12 is 3.14kg/c
4 ABS, the main refrigerant absorbs the surrounding heat and evaporates, whereas that of Freon-113 is 0.153 k
g/czj abs, it is not evaporated but is cooled as a liquid, exits the evaporator 5, and returns to the compressor 1. This pressure m
In AT, during the suction stroke, the main refrigerant in the superheated gas state and the auxiliary refrigerant in the liquid state enter the refrigerant population 19 and the low pressure chamber 1.
7 and enters the compression chamber 14 through the suction hole 20. and,
As the volume of the compression chamber 14 gradually decreases, the main refrigerant is compressed, while the auxiliary refrigerant evaporates. The temperature at this time is 7
0-80℃, pressure is 2-3 kg/cl abs.

Therefore, the heat of the main refrigerant due to the evaporation of the auxiliary refrigerant is
Since 33 kcal/kg is taken away, the temperature of the discharged gas can be lowered.

FIG. 1 shows the results of an experiment to determine how much the discharge gas temperature is reduced by mixing an auxiliary refrigerant. Here, the rotation speed of the compressor is 180 Or, p
, m, and 400 Or, p, n+, and the ratio of the suction gas pressure P to the discharge gas pressure P4 was 20:1.0. According to this, as the proportion of Freon-113 increases, the temperature of the discharged gas decreases rapidly at first, and the rate of decrease gradually decreases until 10% of the mixture is mixed, and the temperature of the discharged gas decreases by about 10℃. Even if the proportion of Freon-113 was increased further, no decrease in the discharged gas temperature was observed.

Furthermore, FIG. 4 shows the results of an experiment to examine how the refrigerating capacity and volumetric efficiency change when the proportion of Freon-113 is increased. According to this,
Although the volumetric efficiency gradually decreases as the proportion of Freon-113 increases, the decrease in the refrigerating capacity is not so great. This is thought to be because the Freon-113 flows in a liquid state together with the refrigerating machine oil inside the evaporator, preventing the refrigerating machine oil from stagnating in the evaporator, thereby increasing the heat exchange efficiency of the evaporator. From this, conversely, even if high viscosity refrigerating machine oil is used, it will not impair the heat exchange efficiency of the evaporator, so it is also possible to increase the efficiency of the compressor by using a high viscosity refrigerating machine with good performance. be.

In the above example, the main refrigerant was Freon-12 and the auxiliary refrigerant was Freon-113, but the invention is not limited to this. When Freon-12 is used as the main refrigerant, the temperature is 0°C.
, 3.14kg/co! The auxiliary refrigerant can be one that is in a liquid state in the ABS state and evaporates in the compressor, and includes, for example, Freon-11, Freon-21, Freon-114, and the like. Further, the main refrigerant may be Freon-22 or the like.

(Effects of the Invention) As described above, according to the present invention, the refrigerant is constituted by mixing the auxiliary refrigerant, which has a higher boiling point than the main refrigerant and evaporates in the compressor, to the main refrigerant in an amount of 1 oii or less. Therefore, the temperature of the discharged gas can be lowered by evaporation of the auxiliary refrigerant in the compressor, and seizure and the like can be prevented. Furthermore, since the auxiliary refrigerant passes through the evaporator in a liquid state, the fluidity of the refrigerating machine oil can be improved, and the heat exchange efficiency in the evaporator or the efficiency of the compressor can be improved. Such an effect is particularly noticeable when a rotary compressor is used in a refrigerator.

[Brief explanation of drawings]

Fig. 1 is a characteristic diagram showing the reduction in discharge gas temperature according to an embodiment of the present invention, Fig. 2 is a configuration diagram of a refrigerator to which the present invention is applied, and Fig. 3 is a diagram showing a pressure 4r6 machine used in the above. A sectional view showing,
FIG. 4 is a characteristic diagram showing changes in refrigerating capacity and volumetric efficiency according to an embodiment of the present invention. 1... Compressor, 2... Condenser, 4... Expansion valve, 5
···Evaporator. Figure 1 Mixing ratio (S) of R1 to R12 of 3 (1 amount) → 2nd
Figure 3

Claims (1)

[Scope of Claims] 1. A refrigerant characterized in that an auxiliary refrigerant that has a higher boiling point than the main refrigerant and evaporates in the compressor is mixed with the main refrigerant in an amount of 10% by weight or less. 2. In a refrigerator in which a refrigeration cycle is constructed by sequentially connecting at least a rotary compressor, a condenser, an expansion valve, and an evaporator, an auxiliary refrigerant that has a higher boiling point than the main refrigerant and evaporates in the compressor is used as described above. A refrigerating machine characterized in that a refrigerant is formed by mixing 10% by weight or less with a main refrigerant, and the refrigerant is sealed in the refrigeration cycle.