JPH109721A - Freezing cycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a freezing cycle in which moisture contained in a refrigerant pipe passage can be removed while a flow rate of a refrigerant circulating pipe passage is being avoided even if refrigerant of hydrogen carbide fluoride group is used. SOLUTION: This freezing cycle is formed by connecting a compressor 1, a condenser 2, a refrigerant flow rate control means 4 and an evaporator 5 with a refrigerant pipe and at the same time refrigerant of hydrogen carbide fluoride group is used as working refrigerant. In this case, a branch circuit 11 is connected to a low pressure gas pipe passage during this cycle, an end part of the branch circuit is provided with a moisture removing device 6, the refrigerant is not allowed to flow to the moisture removing device 6 and then removal of moisture is carried out positively while a reduction of flow rate of the refrigerant is being avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration cycle of a refrigeration / air-conditioning product which can use a fluorocarbon-based refrigerant.

[0002]

2. Description of the Related Art FIG. 6 shows a refrigeration cycle equipped with a moisture removing device for removing moisture in a refrigerant pipe which causes corrosion of metal and deterioration of lubricating oil.
A system diagram of the one proposed in No. 5 is shown. In FIG. 6, 1 is a compressor, 2 is a condenser, 3 is a receiver,
4 is a refrigerant flow control means (expansion means), 5 is an evaporator, and the water removing device 6 is installed in the low-pressure gas line 10 on the downstream side of the evaporator 5.

In the refrigerating cycle, the gas refrigerant pressurized to a high temperature and a high pressure by the compressor 1 enters the condenser 2 through the high pressure gas pipe 7, where it is condensed and liquefied and accumulated in the receiver 3. Next, the liquid refrigerant enters the refrigerant flow control means 4 through the high-pressure liquid pipe 8, where it is adiabatically expanded and decompressed to a low-pressure, low-dryness gas-liquid two-phase state. Into the evaporator 5 through which heat exchange with room air evaporates to become a low-pressure gas refrigerant. This gas refrigerant passes through the water removing device 6 provided in the low-pressure gas pipe 10 to remove moisture and returns to the compressor 1.

[0004]

FIG. 5 shows a water removing device in a low pressure gas line 10 downstream of an evaporator 5 as shown in FIG. 6 when a fluorocarbon refrigerant is used as a working refrigerant. 6 shows the change over time of the ratio of the flow rate of the refrigerant flowing through the refrigerant flow control means 4 when the device 6 is installed (line B in FIG. 5) and when it is not installed (line A in FIG. 5).

[0005] As shown in FIG. 5, when the above-mentioned refrigerant is used, the water removing device 6 is installed in the refrigerant flow control means 4 and the refrigerant pipe downstream of the evaporator 5 as shown in FIG. At line B in FIG. 5, the flow rate of the refrigerant flowing through the refrigerant flow control unit 4 decreases due to the obstruction of the inner wall of the refrigerant flow control unit 4 due to the adhesion of foreign matter. Due to this decrease in the flow rate, the temperature of the compressor 1 rises, and failures such as seizure of the bearing portion and the moving portion may occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide a refrigeration cycle capable of removing water from a refrigerant line while avoiding a decrease in the flow rate of the refrigerant circulation line even when a fluorocarbon refrigerant is used. To provide.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the gist of the invention is to connect a compressor, a condenser, a refrigerant flow rate control means, and an evaporator through a refrigerant pipe to a refrigeration cycle. And a refrigeration cycle using a fluorinated hydrocarbon-based refrigerant as a working refrigerant,
A refrigeration cycle is characterized in that a branch circuit is connected to a low-pressure gas line in the cycle, and a moisture removing device is provided at an end of the circuit.

In the above means, preferably, the water removing device is installed at a position higher than the compressor.
Alternatively, a raising loop that is higher than the compressor is formed in the branch circuit.

According to the above means, the water in the refrigerant line of the refrigeration cycle is converted into water vapor, introduced into the water removing device through the branch circuit branched from the low-pressure gas line, and adsorbed on the trapping portion. Is done. Therefore, according to the above-described means, since the moisture removing device is provided in a portion through which the refrigerant does not pass, the blockage of the refrigerant flow control means due to the provision of the moisture removing device as in the conventional device is avoided, and the refrigerant flow rate is reduced. Is prevented from occurring. Thereby, it is possible to reliably remove the moisture in the refrigerant without causing a decrease in the refrigerant flow rate.

[0010] More specifically, in the above means, the water removing device is provided detachably with respect to the branch circuit. According to this means, the water removing device can be removed and attached in a state where the refrigerant remains in the pipeline of the refrigeration cycle, and the maintainability and handleability are improved.

Another aspect of the present invention is to form a heat pump refrigeration cycle by connecting a compressor, a four-way valve, a heat source side heat exchanger, a refrigerant flow control means, and a use side heat exchanger by refrigerant piping. And a refrigeration cycle using a fluorohydrocarbon-based refrigerant as a working refrigerant, wherein a branch circuit is connected to a low-pressure gas line in the cycle, and a moisture removing device is provided at an end of the circuit. In the refrigeration cycle.
Preferably, in the above means, the low-pressure gas circuit is configured as a suction gas circuit between the compressor and the four-way valve.

According to this means, the branch circuit connected to the water removing device can switch the four-way valve during cooling,
The branch is made from the low-pressure gas pipeline both during heating and during the operation of both cooling and heating, water can be removed without a decrease in refrigerant flow rate.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to FIGS. FIG. 1 shows a system diagram of a refrigeration cycle according to a first embodiment of the present invention. In FIG. 1, 1 is a compressor for compressing a gas refrigerant, 2 is a condenser for cooling and liquefying the gas refrigerant pressurized by the compressor 1 and passing through a high-pressure gas pipe 7, 3 is a receiver, 4 is the condenser described above. Refrigerant flow rate control means (expansion means) 5 for expanding and decompressing the liquid refrigerant from 2 through the high-pressure liquid pipe 8, and heat exchange between the refrigerant through the low-pressure liquid pipe 9 and the indoor air from the control means 4 to convert the indoor air. An evaporator that cools and evaporates and vaporizes the refrigerant.

Reference numeral 10 denotes a refrigerant outlet of the evaporator 5 and the compressor 1
A low-pressure gas pipe 11 connecting the suction port of the gas pipe 10 and a branch circuit branched from the middle of the gas pipe 10. At the pipe end of the branch circuit 11, a moisture removing device 6 for separating moisture in the refrigerant flowing through the low-pressure gas pipe 10 is attached. The water removing device 6 is mounted at a position (high water head position) sufficiently higher than the compressor 1 in the branch circuit 11.

In the refrigeration cycle configured as described above, the gas refrigerant pressurized to a high temperature and a high pressure by the compressor 1 enters the condenser 2 through the high pressure gas pipe 7, where it is condensed and liquefied. Collect in 3. This liquid refrigerant then
The refrigerant enters the refrigerant flow control means 4 through the high-pressure liquid pipe 8, where it is adiabatically expanded and decompressed to a low-pressure, low-dryness gas-liquid two-phase state. , Where it exchanges heat with room air and evaporates to become a low-pressure gas refrigerant. This gas refrigerant is returned to the compressor 1 through the branch part 21 of the branch circuit 11 connected to the moisture removing device 6 through the low-pressure gas pipe 10.

At this time, the water in the low-pressure gas pipe 10 becomes steam and rises in the branch circuit 11, and is adsorbed by the trapping section of the water removing device 6. Therefore, according to the above-described embodiment, since the water removing device 6 is provided in a portion through which the refrigerant does not pass during the operation of the refrigeration cycle, the refrigerant flow path due to the provision of the water removing device 6 as in the conventional device is reduced. No degradation occurs. Further, during the operation of the refrigeration cycle, the refrigerant flowing through the low-pressure gas pipe 10 does not flow into the moisture removing device 6 through the branch circuit 11 and is not filled.

FIG. 2 is a system diagram of a refrigeration cycle according to a second embodiment of the present invention. In this embodiment, the height position of the moisture removing device 6 attached to the pipe end of the branch circuit 11 is set to a position lower than that of the compressor 1, and the branch circuit 11 is After forming a loop portion 11a of a raising loop which is at a high position in terms of the water head, it is connected to the water removing device 6. Other configurations are the same as those of the first embodiment shown in FIG.

FIG. 3 shows a refrigeration cycle according to a third embodiment of the present invention. In this embodiment,
An on-off valve 12 is interposed in a portion of the branch circuit 11 close to the moisture removing device 6, and a connecting portion 13 by flare connection is provided between the on-off valve 12 and the moisture removing device 6. Therefore, in this embodiment, the on-off valve 12 is closed to cut off the connection between the moisture removal device 6 and the low-pressure gas pipe 10 side, and the moisture removal device 6 is detached or attached at the flare connection portion 13 so that the coolant is cooled. The attachment and detachment of the water removing device 6 can be extremely easily performed while remaining in the pipeline.

FIG. 4 shows a refrigeration cycle according to a fourth embodiment of the present invention. In this embodiment,
High pressure gas pipe 7 and low pressure gas pipe 1 at the entrance and exit of compressor 1
0, a four-way valve 14 for switching between cooling and heating is provided, and a low-pressure gas pipe 1 between the four-way valve 14 and the compressor 1 is provided.
A branch circuit 11 branched from 0 is provided.
The water removing device 6 is attached to the end of the.

In this embodiment, during cooling, the refrigerant flows as indicated by the solid arrow, and when the four-way valve 14 is switched to the heating side, the refrigerant flows from the compressor 1 through the four-way valve 14 as indicated by the dashed arrow. Since the branch circuit 11 is branched from between the four-way valve 14 and the compressor 1 which have a low pressure during both cooling and heating, and is connected to the water removing device 6,
The same water removing action as in the embodiment can be obtained.

If the compressor 1 is a low-pressure housing, the inside of the dome of the compressor 1 is at a low pressure, so that the branch circuit 11 may be branched from the dome of the compressor 1.

A low-pressure gas pipe 1 by the moisture removing device 6 is provided between the periphery of the moisture removing device 6 and the low-pressure gas piping 10.
Since the difference in partial pressure of water vapor is caused by the adsorption of water vapor from zero, the water in the refrigeration cycle can be removed regardless of the installation height of the water removal device 6 in each of the above embodiments.

[0023]

The present invention is configured as described above.
According to the present invention, during the operation of the refrigeration cycle, the refrigerant does not pass through the water removing device 6 and foreign matter is prevented from adhering to the refrigerant flow rate control means. It can be carried out.

In addition, during the operation of the refrigeration cycle, the water removing device is not filled with the refrigerant, so that the effect of preventing the adhesion of the foreign matter can be obtained from this aspect as well.

According to the fourth aspect of the present invention, it is possible to remove and attach the water removing device while the refrigerant remains in the pipeline of the refrigeration cycle, so that maintenance and handling can be improved.

Further, according to the fifth and sixth aspects,
Moisture can be reliably removed without any decrease in the flow rate of the refrigerant during both cooling and heating operations.

[Brief description of the drawings]

FIG. 1 is a system diagram of a refrigeration cycle according to a first embodiment of the present invention.

FIG. 2 is an equivalent view of FIG. 1 showing a second embodiment of the present invention.

FIG. 3 is an equivalent view of FIG. 1 showing a third embodiment of the present invention.

FIG. 4 is an equivalent view of FIG. 1 showing a fourth embodiment of the present invention.

FIG. 5 is a flow chart of refrigerant flow control means.

FIG. 6 is an equivalent view of FIG. 1 showing a conventional refrigeration cycle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Condenser 3 Receiver 4 Refrigerant flow control means 5 Evaporator 6 Water removal device 7 High-pressure gas pipe 8 High-pressure liquid pipe 9 Low-pressure liquid pipe 10 Low-pressure gas pipe 11 Branch circuit 12 On-off valve 14 Four-way valve

Claims (6)

[Claims] 1. A refrigeration cycle comprising a compressor, a condenser, a refrigerant flow control means, and an evaporator connected by refrigerant piping to form a refrigeration cycle, and using a fluorocarbon refrigerant as a working refrigerant. A refrigeration cycle comprising a branch circuit connected to a low-pressure gas line in the cycle, and a moisture removing device provided at an end of the circuit. 2. The refrigeration cycle according to claim 1, wherein the water removing device is installed at a position higher than the compressor. 3. The refrigeration cycle according to claim 1, wherein a raising loop that is higher than the compressor is formed in the branch circuit. 4. The refrigeration cycle according to claim 1, wherein the water removing device is provided detachably from the branch circuit. 5. A heat pump refrigeration cycle is formed by connecting a compressor, a four-way valve, a heat source side heat exchanger, a refrigerant flow control means, and a use side heat exchanger by a refrigerant pipe, and a fluorinated hydrocarbon system as an operating refrigerant. A refrigeration cycle using a refrigerant, wherein a branch circuit is connected to a low-pressure gas pipe in the cycle, and a moisture removing device is provided at an end of the circuit. 6. The refrigeration cycle according to claim 5, wherein the low-pressure gas circuit is a suction gas circuit between the compressor and a four-way valve.