JPH0455668A - Moisture removing method of refrigerating device - Google Patents

Abstract

PURPOSE:To obtain high moisture removing effect by a simple constitution utilizing the characteristics of the moisture in refrigerant by a method wherein liberated water, flowing out of a refrigerant evaporator, is retained by a moisture retaining member arranged in a low pressure pipeline at the downstream of the refrigerant evaporator to remove the moisture in a refrigerating device. CONSTITUTION:Refrigerant, having moisture characteristics wherein the saturated moisture concentration of liquid phase is higher than the saturated moisture concentration of gas phase, or R134a, R22 or the like, for example, is used in a refrigerating device 1. Oil, hardly dissolving water, is used for the lubricating oil of a refrigerant compressor 2. As the refrigerant is evaporated in a refrigerant evaporator 6, the concentration of moisture in the liquid is increased. The hydrophilic property of refrigerating machine oil is low and, therefore, moisture, which can not be dissolved by the liquid, is generated as liberated water when the concentration of moisture has exceeded the saturated moisture concentration of the liquid. The liberated water, which flows out of the refrigerant evaporator 6 and flows through a low pressure pipeline 7a, is retained by a moisture retaining member 8 arranged in the downstream of the refrigerant evaporator 6 whereby the moisture, invaded into the refrigerating device 1, is removed to keep the inside of a cycle in the concentration of low moisture while the moisture remover is compact and is prominent in loading property onto a vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for removing moisture from a refrigeration system for removing moisture that has entered the refrigeration system.

[Prior Art 1] Generally, in a refrigeration cycle for a car air conditioner, a rubber hose is used as a part of the refrigerant piping, so moisture easily enters the refrigeration cycle through the rubber hose.

When the moisture concentration in the cycle increases, problems such as internal corrosion in the metal parts that make up the refrigeration cycle and a decrease in cooling performance due to freezing at the expansion valve occur.

Therefore, conventionally, for example, a desiccant is sealed in the receiver of a refrigeration cycle to dehumidify the cycle.

Furthermore, a method has been proposed in which a desiccant is installed in the low-pressure pipe downstream of the evaporator of the refrigeration cycle to remove moisture mixed in the refrigerant gas.

[Problems to be Solved by the Invention] In the method using a desiccant as described above, there is a limit to the moisture absorption ability, and as moisture is absorbed, the amount of moisture left behind increases. Therefore, in order to keep the moisture concentration in the cycle at a low level against invading moisture, it is necessary to enclose a large amount of desiccant.

However, using a large amount of desiccant increases the size of the desiccant and reduces the ease of mounting it on a vehicle, so in reality, the desiccant needs to be replaced as appropriate.

Also, install a desiccant agent in the low pressure piping! , the conventionally widely used refrigerant (R12) exhibits a high saturated moisture concentration in the gas phase, so there is a problem in that a large amount of strong desiccant is required to remove moisture from this gas phase refrigerant. Ta.

The present invention has been made based on the above-mentioned circumstances, and an object thereof is to provide a method for removing moisture from a refrigeration system that can obtain a high moisture removal effect with a simple configuration.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a refrigerant that uses a refrigerant with moisture characteristics in which the saturated moisture concentration in the liquid phase is higher than the saturated moisture concentration in the gas phase. A moisture retaining material is provided in the low-pressure piping downstream of the refrigerant evaporator of the refrigeration device, and the moisture retaining material retains the free water that flows out from the refrigerant evaporator, thereby removing moisture in the refrigeration device. This is a technical means.

``Function: The present invention having the above-mentioned configuration has the advantage that the refrigerant evaporates in the refrigerant evaporator because the moisture concentration in the liquid phase is higher than the saturated moisture concentration in the gas phase, possibly due to the moisture characteristics of the refrigerant used in the refrigeration equipment. Over time, the water concentration in the liquid (in the mixture of refrigerating machine oil and liquid refrigerant) increases.

Eventually, all the refrigerant evaporates, and when the refrigerant vapor reaches a superheat region where it is further heated, water collects and generates free water.

Therefore, by retaining the free water flowing out from the refrigerant evaporator using a moisture retaining material disposed in the low-pressure pipe downstream of the refrigerant evaporator, the moisture within the refrigeration system can be removed.

[Effects of the Invention] According to the present invention having the above-mentioned effects, the moisture in the refrigeration equipment is generated as free water, and the free water is retained by the moisture retaining material. There is no need to use agents.

Therefore, it is possible to obtain a high moisture removal effect with a simple configuration by utilizing the moisture characteristics of the refrigerant, and it is also possible to provide a refrigeration system that is compact and can be easily mounted on a vehicle.

[Example] Next, a method for removing moisture from a refrigeration apparatus according to the present invention will be described based on an example shown in the drawings.9 FIG. 1 is a refrigeration cycle diagram of a refrigeration apparatus.

The refrigeration system 1 of this embodiment includes a refrigerant compressor 2, a refrigerant condenser 3
, a receiver 4 , an expansion valve 5 , and a refrigerant evaporator 6 , which have a well-known structure connected in an annular manner by a refrigerant pipe 7 .

As shown in FIG. 2, a holding section 9 is formed in the low-pressure pipe 7a downstream of the refrigerant evaporator 6 to accommodate a moisture retaining material 8 such as glass wool. The moisture retaining material 8 is a retaining portion 9
It is held down by a wire mesh 10 to prevent it from jumping out.

This refrigeration system 1 uses a refrigerant, such as R
134a, R22, etc. are used. Further, as the refrigerating machine oil (lubricating oil for the refrigerant compressor 2), oil with low hydrophilicity (hard to dissolve water) is used.

Therefore, in the refrigeration system 1 of this embodiment, as the refrigerant evaporates in the refrigerant evaporator 6, as shown by the arrow in the temperature-composition diagram of FIG. ) increases in water concentration.

Since the hydrophilicity of the refrigerating machine oil is low, when the water concentration exceeds the saturated water concentration of the liquid, water that cannot be dissolved in the liquid is generated as free water.

Therefore, by retaining the free water flowing out of the refrigerant evaporator 6 and flowing through the low-pressure pipe 7a with the moisture retaining material 8 disposed downstream of the refrigerant evaporator 6, the moisture that has entered into the refrigeration system 1 can be removed. This allows the cycle to maintain a low moisture concentration.

In this way, in this embodiment, the moisture in the cycle is generated as free water and the free water is retained by the moisture retaining material 8, so there is no need to use a large amount of desiccant as in the conventional method. do not have. Therefore, the refrigeration system 1 does not require regular maintenance such as replacement or inspection, and is compact and easy to mount on a vehicle.

In addition, in order to release the free water retained by the moisture retaining material 8 to the outside of the cycle, an opening is formed in the wall surface of the retaining part 9 to communicate with the outside, and a refrigerant is made to pass through the opening to make it easy for water to pass through. A selectively permeable membrane (for example, a polyimide membrane) that is difficult to use may be provided. This makes it possible to remove moisture within the cycle without limit.

In addition, in the above example, free water is reliably generated by using a refrigerating machine oil with low hydrophilicity, but even when a highly hydrophilic refrigerating machine oil is used, the amount of refrigerating machine oil downstream of the evaporator is If the amount is small, free water can be generated. For this purpose, an oil separator or the like can be used to reduce the amount of refrigeration oil circulating in the refrigeration cycle.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, in which FIG. 1 is a refrigeration cycle diagram of a refrigeration system to which the moisture removal device is applied, FIG. 2 is a cross-sectional view of the main parts of the moisture removal device, and FIG. Figure 3 is a temperature-composition diagram of the refrigerant. In the figure 1... Refrigeration device 6... Refrigerant evaporator 7a... Low pressure piping/moisture retaining material

Claims (1)

[Scope of Claims] 1) In a refrigeration system that uses a refrigerant with water characteristics in which the saturated water concentration in the liquid phase is higher than the saturated water concentration in the gas phase, a low-pressure piping downstream of the refrigerant evaporator of this refrigeration system A method for removing moisture from a refrigeration system, characterized in that a moisture retaining material is provided, and the free water flowing out from the refrigerant evaporator is retained by the moisture retaining material, thereby removing moisture within the refrigeration system.