JPH0583667U - Refrigeration equipment - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] The present invention provides a refrigeration system in which no shortage (uneven distribution) of oil occurs in any of the compressors even when multiple compressors are operated simultaneously or on one side. With the goal. [Structure] The present invention is a refrigeration system in which a plurality of compressors placed on the same plane are mounted and the oil tank of each compressor is connected by an oil equalizing pipe, and the oil of the oil separator connected to the discharge pipe of each compressor is A refrigeration system is characterized in that the return pipes are connected to each other to the suction pipe of the other compressor or the oil sump of the compressor.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a refrigeration system in which a plurality of compressors are mounted, and an oil tank of each compressor is connected by an oil equalizing pipe to share a refrigerant system.

[0002]

[Prior Art]

 FIG. 2 is a refrigerant circuit diagram of a conventional refrigerator. In the figure, 1 and 6 are compressors, 2 and 7 are discharge pipes of the respective compressors 1, 6, 3 and 8 are oil separators connected to the respective discharge pipes 2 and 7, and 4 and 9 are respective oil separators. 3, 8 are gas refrigerant discharge pipes, 11 is a condenser connected to the confluent pipes of both discharge pipes 4 and 9, 12 is a receiver connected to the condenser 11, 19 is an expansion valve connected to the receiver 12, Reference numeral 13 is an evaporator connected to the expansion valve 19, 14 is an accumulator connected to the evaporator 13, 15 and 16 are suction pipes of the compressors 1 and 6, 5 and 10 are connected to the oil separators 3 and 8, respectively. The capillaries, 17 and 18 are blowers, 20 is a temperature-sensing cylinder for expansion valve, 21 is an oil equalizing pipe connecting both the compressors 1 and 6, 3a and 8a are oil separators 3 and 8 to the compressors 1 and 6. It is an oil return pipe to.

In the above circuit, the refrigerants discharged from the compressors 1 and 6 having different capacities or the same capacity enter the oil separators 3 and 8 through the discharge pipes 2 and 7, respectively, and after separating the oil, only the gas cooling medium discharge pipes. It splits through 4 and 9, and is condensed and liquefied in the condenser 11. The liquefied refrigerant is stored in the receiver 12 and is throttled by the expansion valve 19 and then evaporated in the evaporator 13 and passes through the accumulator 14 and the suction pipes 15 and 16 and returns to the compressors 1 and 6. On the other hand, the oil separated by the oil separators 3, 8 is returned to the compressors 1, 6 through the oil return pipes 3a, 8a having the capillaries 5, 10 through the suction pipes 15, 16.

The two compressors 1 and 6 are configured so that either one of them or any one of them can be freely operated, and the oil level of each of the compressors 1 and 6 maintains a proper oil level regardless of the operation conditions. An oil equalizing pipe 21 is provided so that it can be held.

FIG. 3 is a sectional view of an extraction portion of the oil equalizing pipe 21 from the oil tank 1A of the compressor 1 according to the conventional technique. Inside the oil tank 1A of the compressor, oil drops a stirred by a crankshaft (motor in a rotary compressor) and the like in the refrigerant are scattered, and these flow down as an oil film b on the inner wall of the oil tank 1A of the compressor. Then, it collects at the bottom and forms an oil surface e.

[0006]

[Problems to be solved by the device]

 The conventional refrigerator described above has the following problems to be solved.

That is, if 1 in FIG. 2 is a small capacity compressor and 6 is a large capacity compressor, and if such different capacity compressors are operated simultaneously, the pressure in the crankcase of the large capacity compressor 6 is small. Since the capacity is lower than that of the compressor 1, the refrigerant flows in the oil equalizing pipe 21 in the C direction in FIG. At this time, when the oil droplets a and the oil of the oil film b are also sucked together with the refrigerant and two units are operated for a long time, the oil level e of the small capacity compressor 1 is lowered to a position considerably lower than the opening of the oil equalizing pipe 21. However, there was a problem that the lubrication was poor and, in some cases, the compressor 1 was damaged.

In addition to the above, when one of the compressors is started and the other is stopped, the pressure drop in the crankcase causes the oil bubbling phenomenon due to the gasification of the liquid refrigerant, and the oil in the compressor on the stop side is removed. In the foam state, it moves through the oil equalizing pipe to the starting compressor side. As a result, the oil level of the stopped compressor drops.

When it is necessary to start the stopped compressor in this state, there is a problem that the stopped compressor is often damaged due to poor lubrication.

The present invention is intended to provide a refrigeration system in which a plurality of compressors are operated at the same time or one side is operated, and the oil level of each does not drop below the opening of the oil equalizing pipe.

[0011]

Means for Solving the Problems As a means for solving the above problems, the present invention relates to a refrigeration system in which a plurality of compressors placed on the same plane are mounted, and an oil tank of each compressor is connected by an oil equalizing pipe. An object of the present invention is to provide a refrigeration system characterized in that the oil return pipe of the oil separator connected to the discharge pipe of each compressor is connected to the suction pipe of the other compressor or the oil reservoir of the compressor. .

[0012]

[Action]

 Since the present invention is constructed as described above, it has the following effects.

That is, since the oil return pipes of the oil separators connected to the discharge pipes of the compressors are mutually connected to the suction pipe or the oil reservoir of the companion compressor, for example, in the case of simultaneous operation of the compressors having different capacities. , The return oil of the small capacity compressor flows into the large capacity compressor, and the return oil of the large capacity compressor flows into the small capacity compressor, respectively. Replenishment is sufficiently secured, and unnecessary oil flows into the large-capacity compressor through the oil equalizing pipe, and secures the amount of oil in the large-capacity compressor that is insufficient with only the return oil from the small-capacity compressor.

When one is stopped, the pressure in the oil tank is low during operation, so return oil always flows through the compressor on the stop side to the compressor in operation, so a stop compressor is required. The oil level is always secured.

[0015]

【Example】

 An embodiment of the present invention will be described with reference to FIG. The same components as those of the conventional example are designated by the same reference numerals, and the description thereof will be omitted unless necessary.

FIG. 1 is a refrigerant circuit diagram of the refrigerating apparatus of this embodiment. In the figure, the oil return pipe 8 a of the oil separator 8 is upstream of the capillary 5 and the oil return pipe 3 a of the oil separator 3 is upstream of the capillary 10. To each side. Other configurations are the same as the conventional example. That is, the difference between the conventional example and the present embodiment is that the oil return destination of the oil separator 8 on the compressor 6 side is compressed from the compressor 6 to 1 and the oil return destination of the oil separator 3 on the compressor 1 side is compressed. It was only replaced from the machine 1 to the machine 6.

Since the present embodiment is configured as described above, assuming that the compressors 1 and 6 are simultaneously operated and the compressor 1 has a smaller capacity than the compressor 6, the crank of the compressor 1 side is As the case internal pressure becomes higher than that of the compressor 6 and as described above, the oil is deficient in the conventional case, but in the present embodiment, a large amount of oil is returned from the oil separator 8 side, which is deficient. Does not occur. Even if a large amount of oil returns to the compressor 1 side and only a small amount of oil returns to the compressor 6 side from the oil separator 3, the excess amount of the large amount of oil returned to the compressor 1 Moves to the compressor 6 side through the oil equalizing pipe 21, so that both the compressors 1 and 6 always maintain an even level of oil level, and there is no shortage of one. This naturally holds even when the compressor 1 has a large capacity and the compressor 6 has a small capacity.

Next, for example, when the compressor 1 is stopped and the compressor 6 is in operation, the pressure in the crankcase is lower in the compressor 6 in operation, so the return oil is always the compressor on the stop side. Since it flows through the compressor 1 to the compressor 6 in operation, the required oil level of the stopped compressor 1 is secured. This is true even if the compressors 1 and 6 are in the opposite states.

As described above, according to this embodiment, the oil is returned to the compressor 1 through the oil return pipe 8a from the oil separator 8 on the compressor 6 side, and the oil is returned to the compressor 6 through the oil return pipe 8a. Since it is performed through the oil return pipe 3a from the oil separator 3 on the first side, the oil is not unevenly distributed in both compressors 1 and 6, and there is an advantage that neither oil shortage occurs.

[0020]

[Effect of the device]

 Since the present invention is constructed as described above, it has the following effects.

That is, since the return of the oil of the plurality of compressors is made to return from the other separator, the oil is not unevenly distributed due to the state of the compressors, and the proper oil level of each compressor is maintained. There is no lubrication failure, and there is no damage to the compressor.

[Brief description of drawings]

FIG. 1 is a refrigerant circuit diagram of a refrigerating apparatus according to an embodiment of the present invention,

FIG. 2 is a refrigerant circuit diagram of a conventional refrigerator,

FIG. 3 is a sectional view of a portion where an oil equalizing pipe is taken out from a compressor in a conventional example.

[Explanation of symbols]

 1 Compressor 1A Oil tank of compressor 2 Discharge pipe 3 Oil separator 3a Oil return pipe 4 Discharge pipe 5 Capillary 6 Compressor 7 Discharge pipe 8 Oil separator 8a Oil return pipe 9 Discharge pipe 10 Capillary 11 Condenser 12 Receiver 13 Evaporator 14 Accumulator 15 Intake pipe 16 Intake pipe 17,18 Blower 19 Expansion valve 20 Expansion valve temperature-sensitive tube 21 Oil leveling pipe

Claims (1)

[Scope of utility model registration request] 1. In a refrigerating apparatus in which a plurality of compressors placed on the same plane are mounted and an oil tank of each compressor is connected by an oil equalizing pipe, an oil return of an oil separator connected to a discharge pipe of each compressor A refrigeration system characterized in that the pipes are connected to each other to the suction pipe of the other compressor or the oil sump of the compressor.