JPH0455667A - Moisture removing device for refrigerating device - Google Patents

Abstract

PURPOSE:To remove moisture surely utilizing the characteristics of refrigerant by a method wherein liquid refrigerant is molten into high moisture concentration liquid, flowing out of a refrigerant evaporator, to reduce the concentration of saturated moisture of the liquid while free water, generated by the reduction, is retained by a moisture retaining member. CONSTITUTION:High moisture concentration liquid, flowing out of a refrigerant evaporator 6, flows into a reserving chamber 8 as it is and liquid refrigerant is guided through a refrigerant introducing pipe 9b. According to this operation, the mixed molar ratio of the high moisture concentration liquid is moved to the side of refrigerant and the concentration of saturated moisture in the liquid is reduced whereby liberated water is generated from the liquid. The liberated water and the liquid pass through the holes 10b of a pushing plate 10c and only the liberated water is retained by a moisture retaining member 10a while the liquid, from which the liberated water is removed, is returned into a main flow through a discharging pipe 10d. The liberated water, retained by the moisture retaining member 10a, is discharged to the outside of a refrigerating device 1 after passing through a selective penetration film 12 and the moisture, removed from the inside of a cycle, can be discharged to the outside of the refrigerating device 1 whereby the inside of the cycle can be kept in a low moisture concentration against the invasion of moisture at all times.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application 1 The present invention relates to a moisture removal device for a refrigeration system for removing moisture that has entered the refrigeration system.

[Prior Art] Generally, in a refrigeration cycle for a car air conditioner, a rubber hose is used as a part of the refrigerant piping, and moisture infiltrates into the refrigeration cycle through this 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 receiver and reduces the ease of mounting it on the vehicle I/\, so in reality, the desiccant needs to be replaced as appropriate.

In addition, in low-pressure piping equipped with a desiccant, since the conventionally widely used refrigerant (R42) exhibits a high saturated moisture concentration in the gas phase, a large amount of powerful drying is required to remove moisture from this gas phase refrigerant. There was a problem in that it required a chemical agent.

In addition, in the past, the above-mentioned R12 was generally used as a refrigerant in car air conditioners, but in recent years, R134a, which has a higher saturated water concentration in the liquid phase than in the gas phase (
A new refrigerant (with characteristics opposite to those of R, 12) is attracting attention for use in car air conditioners. However, due to the moisture characteristics of R134a, there was a problem in that a sufficient dehumidification effect could not be obtained using a conventional desiccant in the receiver. Therefore, in view of the problems of the prior art as described above, the present invention aims to perform reliable moisture removal by utilizing the characteristic of some refrigerants that the saturated moisture concentration in the liquid phase is higher than the saturated moisture concentration in the gas phase. An object of the present invention is to provide a moisture removal device for a refrigeration equipment that can perform the following functions.

[Means for Solving the Problems] In order to achieve the above object, the present invention uses a refrigerant having moisture characteristics in which the saturated moisture concentration in the liquid phase is higher than the saturated moisture concentration in the gas phase, and a highly hydrophilic refrigerating machine oil. It is applied to a refrigeration system using a refrigeration system, and includes a storage chamber for storing a high moisture concentration liquid flowing out from a refrigerant evaporator of this refrigeration system, and a liquid refrigerant is guided into this storage chamber, and the liquid refrigerant is used to reduce the high moisture concentration in the storage chamber. The method comprises a free water generating means that generates free water from the high water concentration liquid by dissolving it in a liquid, and a water retaining means that includes a moisture retaining material and causes the generated free water to be retained in the moisture retaining material. Use technical means.

[Function] The present invention having the above-mentioned configuration has a moisture characteristic of the refrigerant used in the refrigeration system, and the moisture concentration in the liquid phase is higher than the saturated moisture concentration in the gas phase. Therefore, the water concentration in the liquid (mixture of refrigerating machine oil and liquid refrigerant) increases.

Therefore, free water can be generated by storing the high water concentration liquid flowing out from the refrigerant evaporator in a storage chamber, dissolving the liquid refrigerant in the high water concentration liquid, and lowering the saturated water concentration of the liquid.

By retaining this generated free water with a moisture retaining material, moisture within the refrigeration system is removed.

[Effects of the Invention] According to the present invention having the above-mentioned effects, free water is generated using the moisture characteristics of the refrigerant and the moisture characteristics of the refrigerating machine oil, and the generated free water is retained by the moisture retaining material. Since moisture that has entered the device is removed, moisture can be reliably removed without using a large amount of desiccant as in the conventional method.

[Example] Next, a moisture removal device for a refrigeration equipment according to the present invention will be described based on an example shown in the drawings.

FIG. 1 is a refrigeration cycle diagram of a refrigeration system to which a moisture removal device is applied.

The refrigeration system 11 of this embodiment is composed of functional parts such as a refrigerant compressor 2, a refrigerant condenser 3, a receiver 4, an expansion valve 5, and a refrigerant evaporator 6, which are connected in an annular manner by a refrigerant pipe 7. Has a structure.

Normally, a fluorocarbon-based refrigerant R12 is used in a refrigeration cycle such as a car air conditioner. , for example R134a, or R22
is used. Further, as the refrigerating machine oil (lubricating oil for the refrigerant compressor 2), a highly hydrophilic oil, such as a PA or G type oil, is used.

Therefore, in the refrigeration system 1 of this embodiment, as the refrigerant evaporates in the refrigerant evaporator 6, as shown in the temperature-composition diagram of FIG. Since the moisture concentration increases, a high moisture concentration liquid in which liquid refrigerant is dissolved in refrigerating machine oil flows out from the refrigerant evaporator 6.

The moisture removal device applied to this refrigeration device 1 has a storage chamber (a second
(see figure) 8, and a free water generating means for introducing a liquid refrigerant into the storage chamber 8 and dissolving the liquid refrigerant in the high water concentration liquid in the storage chamber 8 to generate free water from the high water concentration liquid. 9, and a moisture retaining means (see FIG. 2) 10, which is provided with a moisture retaining material 10a and causes the generated free water to be retained in the moisture retaining material 10a.

The storage chamber 8 is provided downstream of the refrigerant evaporator 6 and connected to the lower side of the refrigerant pipe 7, as shown in FIG. 8. In addition, FIG. 2 is a sectional view of the main part of the moisture removal device.

The free water generating means 9 includes a liquid storage chamber 9a that stores liquid refrigerant upstream of the refrigerant evaporator 6, a refrigerant introduction pipe 9b that connects the liquid storage chamber 9a and the storage chamber 8, and a refrigerant introduction pipe 9b that connects the liquid refrigerant to the storage chamber 8. It is composed of a flow rate adjustment valve 9C provided in the. The flow rate regulating valve 9C has its valve opening degree controlled depending on the degree of superheating of the storage chamber 8, and includes a heat-sensitive cylinder 9d and a capillary tube 9C that transmit temperature changes in the storage chamber 8 as pressure changes.

When looking at the saturated water concentration in the liquid with respect to the mixed molar ratio of refrigerating machine oil and liquid refrigerant, the free water generating means 9 can be used to increase the saturated water concentration as the mixed molar ratio moves toward the refrigerant side, as shown in FIG. Since the liquid refrigerant is introduced into the storage chamber 8, the mixing molar ratio of the high water concentration liquid is shifted to the refrigerant side, and the saturated water concentration is lowered, thereby generating free water.

The moisture retaining means 10 includes a moisture retaining material 10a (for example, glass wool) disposed at the bottom of the storage chamber 8, a holding plate 10C that fixes the moisture retaining material 10a and is provided with a large number of holes 10b. It consists of a discharge pipe 10d for returning the liquid from which free water has been removed into the mainstream.

This moisture retaining means 10 uses the differential pressure between the upstream side and the downstream side of the discharge pipe 10d to retain free water in the moisture retaining material 10a, and the free water and liquid (
Refrigerating machine oil + liquid refrigerant), only free water is the moisture retaining material 10a
The remaining liquid is returned to the main stream through the discharge pipe 101j, and together with the gas refrigerant flowing through the refrigerant pipe 7,
The refrigerant is sucked into the refrigerant compressor 2.

In this embodiment, in order to release the free water retained by the moisture retaining material 10a to the outside of the freezer bag 1, an opening 11 communicating with the outside is formed on the bottom side of the moisture retaining material tOa.
1 is provided with a selectively permeable membrane (for example, a polyimide membrane) 12 that easily allows water to pass through but does not allow refrigerant to pass through.

Next, the operation of this embodiment will be explained.

When the refrigerant whose pressure has been reduced by the expansion valve 5 is evaporated in the refrigerant evaporator 6, in the refrigerant evaporator 6, as shown by the arrow in the temperature-composition diagram of FIG. The water concentration inside increases.

At this time, since the refrigeration system 1 of this embodiment uses highly hydrophilic refrigeration oil, the refrigerant evaporator 6
A liquid with high moisture concentration (liquid refrigerant dissolved in refrigerating machine oil) will flow out.

The high moisture concentration liquid flowing out from the refrigerant evaporator 6 flows into the storage chamber 8 as it is, and mixes with the liquid refrigerant introduced through the refrigerant introduction pipe 9b. As a result, the mixing molar ratio of the high water concentration liquid shifts to the refrigerant side, and the saturated water concentration in the liquid decreases, so that free water is generated in the liquid.

This free water and liquid pass through the hole 10b of the holding plate 10c,
Only free water is retained by the moisture retaining material 10a, and the liquid from which the free water has been removed is returned to the mainstream via the discharge pipe 10d.

The free water retained by the moisture retaining material 10a is transferred to the selectively permeable membrane 1.
The liquid that passes through the refrigerant evaporator 2 and is discharged to the outside of the refrigeration device 1 and returned to the mainstream is sucked into the refrigerant compressor 2 together with the gas refrigerant that has flowed out from the refrigerant evaporator 6.

In this manner, in this embodiment, the water removed from the inside of the cycle can be released to the outside of the refrigeration apparatus 1, so that the inside of the cycle can always be kept at a low water concentration even when water enters.

Further, the moisture removal device of this embodiment does not require the use of a large amount of desiccant, is compact, and does not require periodic maintenance such as replacement or inspection unlike conventional devices.

Next, a second embodiment of the present invention will be described.

FIG. 5 is a refrigeration cycle diagram of the refrigeration system 1 to which the moisture removal device is applied, and FIG. 6 is a sectional view of the main parts of the moisture removal device.

In the first embodiment described above, free water was generated by directly mixing the liquid refrigerant with the high moisture concentration liquid in the storage chamber 8, but in this example, the high moisture concentration liquid in the storage chamber 8 was cooled. By liquefying the gas refrigerant flowing in the main stream and introducing the solution, the saturated water concentration in the liquid is lowered and free water is generated.

A method of cooling the high water concentration liquid in the storage chamber 8 is to install a spiral cooling pipe 9 inside the storage chamber 8 through which a low-temperature refrigerant guided from the liquid storage chamber 9a passes. 9
This is done by exchanging heat between the low temperature refrigerant passing through f and the high moisture concentration liquid.

Therefore, the free water generating means 9 of this embodiment has a liquid storage chamber 9a.
and a cooling pipe 9f.

[Brief explanation of the drawing]

1 to 4 show a first embodiment of the present invention, in which FIG. 1 is a refrigeration cycle diagram of a refrigeration system to which a moisture removal device is applied, FIG. 2 is a sectional view of main parts of the moisture removal device, and FIG. Figure 3 shows the temperature-composition aspect of the refrigerant, Figure 4 is a graph showing the relationship between the mixing molar ratio and the saturated water concentration in the liquid mixture, and Figures 5 and 6 show the second embodiment of the present invention. FIG. 5 is a refrigeration cycle diagram of a refrigeration system to which the moisture removal device is applied, and FIG. 6 is a sectional view of the main parts of the moisture removal device. In the diagram

Claims (1)

[Scope of Claims] 1) Applicable to a refrigeration system using a refrigerant having moisture characteristics in which the saturated moisture concentration of the liquid phase is higher than the saturated moisture concentration of the gas phase and a highly hydrophilic refrigerating machine oil, (a) A storage chamber for storing a high moisture concentration liquid flowing out from a refrigerant evaporator of this refrigeration device; , a free water generating means for generating free water from the high water concentration liquid, and (c) a water retaining means comprising a moisture retaining material and causing the generated free water to be retained in the moisture retaining material. Device.