JPS60200054A - Refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a refrigeration system using a rotary compressor having a check valve, and particularly relates to reducing pressure loss thereof.

Structure of the conventional example and its problems As shown in Fig. 1, the refrigeration equipment used in the conventional freezer/refrigerator consists of a rotary compressor, a casing 1. Capacitor 2. Capillary tube 3. The evaporators 4 are connected in sequence to form a cooling system.

5 is an on-off valve that opens and closes in synchronization with the stoppage of the rotary compressor 1, and when the rotary compressor 291 stops, the high-pressure, high-temperature refrigerant in the condenser 2 flows through the capillary tube 3 into the low-pressure, low-temperature enochorator 4;
This prevents the evaporator 4 from becoming a heat load. 6 is a check valve, and when the rotary compressor 1 stops, the high-pressure, high-temperature gas refrigerant inside the rotary compressor 1 flows out from the machine room 7, flows backward through the suction pipe 8, and flows into the low-pressure, low-temperature evaporator 4, causing a heat load. This is to prevent this from happening. The check valve 6 is composed of a ball valve 9, a mesh-like stop/knee 10 for preventing movement of the ball valve 9, and a valve seat 11, and is formed by integrally fixing the stopper 10 and the valve seat 11 to a casing 12. ing.

A refrigerant passage 13 having a smaller diameter than the diameter of the ball valve 9 is provided in the valve seat 11 . The suction pipe 8 exchanges heat with the capillary tube '3, promotes supercooling of the refrigerant in the capillary tube 3, and increases the refrigeration effect of the refrigeration cycle.

In the above configuration, when the rotary compressor 1 is stopped, the on-off valve 5 is closed, and the check valve 6 is also caused by the backflow of refrigerant from the mechanical part 7 of the rotary compressor 1. The circuit is closed by being pressed against the valve seat 11 to prevent high pressure and high temperature refrigerant in the rotary compressor and condenser from flowing into the evaporator 4. Furthermore, while the rotary compressor 1 is in operation, the on-off valve 6 is opened, and the check valve 6 is also opened as the ball valve 9 is pushed by the stopper 10 due to the refrigerant flow as shown by the solid line in Fig. 1. , the refrigerant is a rotary compressor 1. Capacitor 2. Capillary tube 3. Evaporator 4. After flowing into the suction pipe 8 and exchanging heat with the capillary tube 3 in the suction pipe 8, it becomes a gas refrigerant with a relatively high temperature and a relatively large volume, and flows into the refrigerant passage 13 of the check valve 6, and then flows into the rotary compressor 1. Normal cooling operation is performed. The smaller the refrigerant passage 13 provided in the valve seat 11 of the check valve 6, the smaller the amount of leakage when the ball valve 7 is closed, but on the other hand, during rotary compressor operation, the refrigerant passage 13 causes a large pressure drop. This has the disadvantage that the suction pressure of the rotary compressor 1 is reduced and the performance is degraded.

Furthermore, by exchanging heat between the suction pipe 8 and the capillary N tube 3, supercooling of the refrigerant in the capillary N tube 3 is promoted and the refrigeration effect of the refrigeration cycle is increased.
On the other hand, the temperature of the gas refrigerant in the suction pipe 8 rises, turning into superheated gas with a relatively high temperature and large specific volume, which flows through the suction pipe 8 and the check valve 6. Refrigerant passage 13
The disadvantage was that the pressure loss caused by this process was extremely large.

Purpose of the Invention Therefore, the present invention reduces the amount of gas refrigerant flowing through the suction pipe and the check valve, lowers the temperature of the refrigerant, reduces the pressure loss occurring in the suction pipe and the check valve, and reduces the temperature of the intake gas of the rotary compressor. The purpose is to

Structure of the Invention In order to achieve this object, the present invention divides the evaporator into two, and provides a bypass circuit between the first evaporator and the second evaporator and bypassing the second evaporator and the check valve. By exchanging heat with the capillary tube and part of the condenser in the bypass circuit, and by providing a radiator with a reverse valve mechanism downstream from the heat exchange section of the bypass circuit, refrigerant is prevented from flowing into the evaporator when the rotary compressor is stopped. At the same time, it not only reduces the amount of refrigerant passing through the suction pipe and check valve, but also reduces the temperature of the refrigerant, thereby reducing the pressure loss occurring in the second evaporator suction pipe and check valve. Furthermore, the suction temperature of the compressor is reduced by radiating heat from the high-temperature refrigerant in the radiator after promoting supercooling of the refrigerant in the capillary tube.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings, but the same components as those of the prior art will be denoted by the same reference numerals and detailed explanations thereof will be omitted. In FIG. 2, rotary compressor 1. Capacitor 2. Capillary tube 3. A cooling system is formed by sequentially connecting a first evaporator 4a and a second evaporator 4b. Reference numeral 6 denotes an on-off valve that opens and closes in synchronization with the stoppage of the rotary compressor 1, and is provided at the outlet of the condenser 2. 6 is a check valve provided in the suction pipe 8. 14 is a gas-liquid separator, and the first evaporator 4
a and the second evaporator 4b. 16 is the first
The inlet part IE5a is connected to the gas-liquid separator 14 in a bypass circuit through which gas refrigerant flows out of the refrigerant flowing out from the evaporator 4a.
In addition, the outlet section 16b is connected to the inlet vibrator 16 of the rotary compressor 1. The bypass circuit exchanges heat with the first evaporator in a section A, and then exchanges heat with the capillary tube 3 and the outlet vibe 2' of the condenser 2 in a section B, as shown by the dashed line. Reference numeral 17 denotes a radiator with a check valve mechanism, which is provided between the heat exchange section and the inlet pipe 16. The radiator 17 with a check valve mechanism includes a ball valve 18 , a mesh-like stopper 19 for preventing movement of the ball valve 18 , a valve seat 20 , and a casing 22 having heat radiation fins 21 . The valve seat 20 is integrally fixed. A refrigerant passage 23 having a diameter smaller than that of the ball valve 18 is provided in the valve seat 2o. The bypass circuit 15 is formed of a relatively small diameter pipe so that a predetermined gas refrigerant flows therethrough, and is designed to have a resistance greater than the pipe resistance of the second evaporator 4b, suction pipe 8, and check valve 6. Further, the suction pipe 8 and check valve 6 between the second evaporator 4b and the inlet vibrator 16 are insulated with a heat insulating material (0 parts) to prevent the temperature of the refrigerant in the suction pipe 8 from rising.

In the above configuration, when the rotary compressor 1 is in operation, the on-off valve 5 is opened, and the check valve 6 is also opened by pressing the ball valve 9 against the stopper 10 as shown by the dotted line in FIG. 2 due to the refrigerant flow. ing. The refrigerant discharged from the rotary compressor 1 is transferred to the condenser 2. Capillary tube 3° flows into first evaporator 4a and gas-liquid separator 14. The refrigerant that has entered the gas-liquid separator 14 is separated into gas and liquid, and the liquid refrigerant flows to the second evaporator 4b, where it evaporates and becomes a low-temperature gas refrigerant that is passed through the suction pipe 8. It flows through the check valve 6 and enters the inlet vibe 16. Also, gas refrigerant uses bypass circuit 1.
5, the liquid refrigerant is completely evaporated in the first evaporator 48 section, becomes 100% low-temperature gas refrigerant, and enters the heat exchange section 13 with the capillary tube 3. The low-temperature gas refrigerant promotes supercooling of the refrigerant in the capillary tube 3 in the heat exchange section B, and then exchanges heat with the outlet vibe 2' of the condenser 2, becoming a high-temperature gas refrigerant and dissipating the heat with a check valve mechanism. Enter vessel 17. The refrigerant that has entered 17 is opened by pressing the check valve 18 against the stopper 19 due to the refrigerant flow, is cooled by heat radiation, and flows into the inlet vibe 16 as a gas refrigerant having a temperature close to the outside air temperature. The low-temperature gas refrigerant flowing in from the suction pipe 8 at the inlet vibrator 16 and the gas refrigerant heat-radiated and cooled by the radiator 17 with a check valve mechanism in the bypass circuit 16 are transferred to the inlet vibrator 1.
In the rotary compressor 1, the refrigerant is fluorinated and becomes a relatively low temperature gas refrigerant. Therefore, suction pipe 8
．． Since the flow rate of the refrigerant flowing through the check valve 6 can be lower than in the conventional case and the temperature is not heated, it can be reduced from a to b as shown in FIG. 3, and the specific volume can be reduced from the conventional C to d. Therefore, the flow rate of refrigerant flowing through the suction pipe 8° check valve 6 is:
As the specific volume J\ decreases, the conventional e decreases to f as shown in Fig. 4, and the suction pipe 8. The pressure loss caused by the check valve 6 can also be significantly reduced from the conventional 9 to h. Further, the refrigerant flowing through the bypass circuit 15 exchanges heat with the capillary tube 3 to supercool the refrigerant in the capillary tube 3, so that the same increase in the refrigerating effect as in the conventional case can be obtained. Thereafter, it enters the post-inlet pipe 16 which has been cooled by heat radiation in the radiator 17 with a check valve mechanism, and is mixed with the low-temperature gas refrigerant flowing from the suction pipe 8.
The temperature of the intake gas to the compressor 1 can be reduced, and the rotary compressor 1 can be operated efficiently. Next, when the rotary compressor 1 stops, the on-off valve 6 is closed.

The check valve 6 is also the mechanical part 7 of the rotary compressor 1.
The ball valve is closed by being pushed as shown by the dotted line 9' in FIG. 2 due to the backflow of refrigerant from the ball valve. Similarly, the ball valve 19 in the radiator 17 with a check valve mechanism is also connected to the dotted line 18 in FIG.
As shown in FIG. 1, the circuit is closed by being pressed against the valve seat 20, so the rotary compressor 1. It is possible to prevent the high-pressure high-temperature refrigerant in the condenser 2 from flowing into the evaporators 4a and 4b and causing a heat load.

Therefore, the pressure drop between the suction pipe 8 and the check valve 6 can be reduced without widening the refrigerant passage between the suction pipe 8 and the check valve 6, and the temperature of the suction gas to the rotary compressor 1 can also be lowered. Since it is possible to prevent high-pressure high-temperature refrigerant from flowing into the evaporator ports 4a and 4b when the rotor IJ-confrenozer 1 is stopped, a highly efficient refrigeration system can be obtained.

Effects of the Invention As is clear from the above explanation, the present invention provides an on-off valve that opens and closes in synchronization with the stoppage of the rotary compressor on the upstream side of the first evaporator and the second evaporator, and on the downstream side of the second evaporator. A check valve is provided between the first evaporator and the second evaporator, and a bypass circuit is provided between the first evaporator and the second evaporator to bypass the second evaporator and the check valve. Since a radiator with a check valve mechanism is installed downstream of the heat exchange section, pressure loss between the suction pipe and the check valve can be reduced without widening the refrigerant passage between the suction pipe and the check valve. At the same time, the temperature of the intake gas to the rotary compressor can be lowered, and the high-pressure, high-temperature refrigerant from the rotary compressor and condenser can be prevented from flowing into the evaporator when the rotary compressor is stopped, making it possible to obtain a highly efficient refrigeration system.

[Brief explanation of drawings]

Fig. 1 is a refrigerant circuit diagram of a conventional refrigeration system, Fig. 2 is a refrigerant circuit diagram of a refrigeration system showing an embodiment of the present invention, and Fig. 3 is a diagram of a superheated gas refrigerant at constant pressure in the conventional example and the present invention. FIG. 4 is a characteristic diagram showing the relationship between temperature and specific volume, and FIG. 4 is a characteristic diagram showing the relationship between flow velocity and pressure inside the suction pipe and check valve. 1... Rotary compressor, 2... Old capacitor, 3... Capillary tube, 4a...
・Mark: 1st evaporator, 4b: 2nd evaporator, 6: Check valve, 16: Bypass circuit, 17: Heat dissipation with check valve mechanism vessel. Name of agent: Patent attorney Toshio Nakao (1st person)
Figure 2

Claims (1)

[Claims] (1) A rotary compressor, a condenser, a capillary tube, a first evaporator, and a second evaporator are connected in series to form a cooling system, and a cooling system is formed upstream of the first evaporator in synchronization with the stoppage of the rotary compressor. A check valve is provided on the downstream side of the second evaporator, a bypass circuit is provided between the first evaporator and the second evaporator to bypass the second evaporator and the check valve, and the bypass circuit is connected to a capillary tube. and a radiator with a check valve mechanism, which exchanges heat with a part of the condenser and is provided downstream of the heat exchange section of the bypass circuit.