JPH0674613A - Structure of accumulator in refrigeration cycle - Google Patents

Abstract

PURPOSE:To prevent liquid from being returned back and further to prevent clogging from being generated by a method wherein an extremity end of a refrigerant inlet pipe is arrange near a bottom part of a container and an oil returning pipe having a relative wide diameter and a relative long length is connected between an outlet pipe and the bottom part of the container. CONSTITUTION:A refrigerant inlet pipe 2 for use in feeding refrigerant from an evaporator is connected within an accumulator container 1. An extremity end 2a of the inlet pipe 2 is arranged so as to be located near a bottom part within the container 1. An extremity end 6a of a refrigerant outlet pipe 6 connected to the accumulator container 1 and for use in guiding refrigerant to a compressor is arranged so as to be located near a ceiling part within the container 1. One end of an oil returning pipe 10 such as a copper pipe made of raw material having superior heat transfer characteristic with an inner diameter of 3mm and a length of 750mm (a capacity of 5.3cc) or so due to a capacity of the compressor of 7cc is connected to the bottom part of the container 1. This pipe 10 is connected to the refrigerant outlet pipe 6 through a connector 12 after being turned around in a substantial horizontal direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure improvement of a compressor, a condenser, a pressure reducing means, an evaporator and an accumulator in a refrigerating cycle which is circulatively connected to an accumulator through a refrigerant pipe. Recently, compressor manufacturers have become more and more liable to rely on reliability, and the usage conditions of compressors are being replaced by more stringent conditions than before, and liquid back-up at start-up (a negative pressure phenomenon that occurs immediately after start-up sucks liquid from the outlet pipe for a moment About 20 seconds or less,
In some cases, the specification that was less than 40cc has changed to the specification that the liquid bag is 0. This is the structure of the accumulator for preventing such liquid back and phenomenon.

[0002]

2. Description of the Related Art As a conventional accumulator of this type,
As shown in FIG. 6, the tip 2a of the inlet pipe 2 is located near the ceiling of the accumulator container 1 so that the refrigerant is blown out from the inlet pipe 2, and the mesh 3 and the obstacles are blocked below the inlet pipe 2. A screen 5 composed of a plate 4 is arranged, and a refrigerant outlet pipe 6 is provided below the screen 5.
It is known that the pipe 6 is erected so that the tip 6a of the pipe 6 is located, an orifice 8 having a diameter of about 1 mm is bored near the bottom of the pipe 6, and the oil is returned from the orifice 8.

[0003]

However, in the case where the orifice is bored below the conventional outlet pipe, the oil can be returned by the orifice, but the liquid refrigerant also returns together with the oil, which causes the liquid bag. It was. Further, the diameter of the hole of the orifice may be reduced in order to minimize the liquid back, but there are problems that the processing accuracy must be improved and that the hole is small and clogging easily occurs. Therefore, the present invention has been made in view of the drawbacks of the prior art,
It is an object of the present invention to provide a structure in which the liquid bag can be suppressed as much as possible and clogging is less likely to occur.

[0004]

That is, the present invention relates to an accumulator in a refrigeration cycle in which a compressor, a condenser, a pressure reducing means, an evaporator and an accumulator are circulated and connected to each other via a refrigerant pipe, and a tip of a refrigerant inlet pipe of the accumulator. Is arranged to the vicinity of the bottom of the accumulator container and the tip of the refrigerant outlet pipe is arranged to the vicinity of the ceiling of the accumulator container, and the bottom of the accumulator container and the refrigerant outlet pipe are constituted by an oil return pipe or a capillary tube. This object is achieved by the structure of the accumulator of the refrigeration cycle in communication. The oil return pipe that connects the bottom of the accumulator container and the refrigerant outlet pipe is made of a material having a smaller diameter and a relatively longer length than the refrigerant outlet pipe and excellent thermal conductivity, and a heating means around the oil return pipe. Should be installed.

[0005]

In the apparatus according to the present invention, the refrigerant compressed by the compressor is liquefied by the condenser, and after the pressure is adjusted by the pressure reducing means, the refrigerant is changed from liquid to gas to evaporate latent heat. Then, the refrigerant that has become almost gaseous is guided to the accumulator, and the refrigerant that has returned in the liquid state is vaporized and then returned to the compressor together with the oil. In the accumulator, the refrigerant and oil remaining in the accumulator container are agitated because the tip of the refrigerant inlet pipe is extended to the bottom of the container, which promotes vaporization of the refrigerant. The vaporized refrigerant is guided to the compressor via the outlet pipe, while the oil in the container returns to the compressor via the oil return pipe connected to the bottom. In the present invention, although the oil return pipe has a large diameter, its length is increased to provide resistance.
In addition, the liquid refrigerant also flows through the oil return pipe,
In the case where the heating means is installed around the oil return pipe, the liquid vaporizes while the refrigerant flows, so that the vaporized refrigerant flows to the compressor.

[0006]

The present invention will be described in detail below with reference to the illustrated embodiments. In the figure, reference numeral 1 denotes an accumulator container, and a refrigerant inlet pipe 2 for connecting a refrigerant from the evaporator side is connected to the inside of the container 1. In this embodiment, a tip 2a of the inlet pipe 2 is a bottom portion of the container 1. It is arranged so that it is located in the vicinity. 6 is a refrigerant outlet pipe for guiding the refrigerant connected to the accumulator container 1 to the compressor,
The tip 6a of the outlet pipe 6 is arranged so as to be located near the ceiling in the container 1. Since the capacity of the compressor is 7cc class at the bottom of the container 1, the inner diameter is 3mm and the length is 750mm.
One end of an oil return pipe 10 made of a material having a high thermal conductivity such as a copper pipe (capacity: 5.3 cc) is connected, and the pipe 10 is circulated substantially horizontally and then the refrigerant outlet pipe 6 via a connector 12 Connected with.

In the accumulator of this embodiment, the moisture absorbent 14 is arranged directly below the horizontally arranged oil return pipe 10, and as shown in the vicinity of the oil return pipe 10, the condenser 16 and the condenser of the refrigeration cycle are provided. Placed near the fan 17
It is configured to exchange heat with the heat generated in the condenser 16.

Next, FIG. 3 shows a type in which a plurality of heat exchange fins 20 are attached to the outer circumference of the oil return pipe 10 in order to further promote heat exchange with the outside air in the oil return pipe 10. In addition, when the refrigeration cycle is used in the cold season, the one shown in FIG. 4 may return to the liquid as a refrigerant only by heat exchange because the outside air itself is cold, so that the oil return pipe 10 has an outer periphery. It is of a type in which a heat heater 22 is installed, and the heater 22 is controlled while the temperature is detected by a controller 24.

FIG. 5 shows a container 1 instead of the oil return pipe 10 in the first, second and third embodiments.
The bottom portion and the refrigerant outlet pipe 6 are connected by a spirally bent capillary tube 26. In this case as well, the diameter can be made larger than that of the conventional orifice drilled in the outlet pipe.

In this embodiment, the inner diameter of the oil return pipe is 3
Although the mm and the length are set to 750 mm, the present invention is not limited to this. The inner diameter D and the length L of the pipe are determined by the capacity V of the compressor, and there are various ways of setting. However, when the diameter is set to about 1 mm like the conventional orifice, it is easy to cause clogging in the pipe,
2mm or more is preferable, and the length L of the oil return pipe 10 is L
It is preferable that the capacity in the pipe 10 does not exceed the capacity V of the compressor.

[0011]

[Equation 1] V> π · (D / 2) ² · L

In the structure of the accumulator according to this embodiment having the above-mentioned structure, the liquid / gas mixture refrigerant flowing from the refrigerant inlet pipe 2 is blown out from the tip 2a of the inlet pipe 2 toward the container and already accumulated. The oil and the refrigerant liquid are stirred to promote the vaporization of the refrigerant. The vaporized refrigerant is returned to the compressor (not shown) in a gaseous state through the outlet pipe 6 having the tip 6a near the ceiling of the container 1. On the other hand, since the oil return pipe 10 is connected to the bottom of the container 1, the liquid oil and the refrigerant flow into the pipe 10. However, compared to the inner diameter of the pipe 10,
It does not flow vigorously due to the long relationship such as 750 mm, but it has some flow resistance, and while flowing in the pipe 10, the liquid refrigerant is heat-exchanged and vaporized oil. Near the end of the return pipe 10, all the refrigerant has evaporated.

In addition, in the case where a heater is installed around the oil return pipe 10 or the one designed to exchange heat with the heat of the condenser, the refrigerant is easily vaporized by removing the heat of the condenser. become. Further, in the case where a hygroscopic material is arranged below the oil return pipe 10, the pipe 10 itself is cooled by evaporating the refrigerant liquid in the oil return pipe 10,
Condensation adheres to 10. This is because the adhered condensed water is sucked into the water absorbing material to re-evaporate the water. Further, in the accumulator according to the present embodiment, even if there is a liquid refrigerant in the accumulator when the compressor is started, the oil return pipe is designed with a relatively long one,
It vaporizes by the time it reaches the compressor, preventing it from flowing into the compressor as liquid.

[0014]

As described above, the accumulator structure according to the present invention is different from the conventional one in that the tip of the refrigerant inlet pipe is installed near the bottom of the container, and instead of the orifice drilled in the refrigerant outlet pipe in the conventional one. Since an oil return pipe having a relatively wide diameter and a length is connected between the outlet pipe and the bottom of the container, it is less likely to be clogged and vaporized refrigerant can be sent to the compressor. Further, since the oil return pipe is installed, it is possible to prevent the liquid back phenomenon which is easily caused in the conventional device.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an accumulator according to a first embodiment of the present invention.

2 is a plan view of the accumulator of FIG. 1. FIG.

FIG. 3 is a vertical sectional view of an accumulator according to a second embodiment.

FIG. 4 is a plan view of an accumulator according to a third embodiment.

FIG. 5 is a vertical sectional view of an accumulator of a fourth embodiment.

FIG. 6 is a vertical sectional view of an accumulator showing a conventional technique.

[Explanation of symbols]

 1 Container 2 Refrigerant Inlet Pipe 2a Tip 3 Mesh 4 Baffle 5 Screen 6 Refrigerant Outlet Pipe 6a Tip 8 Orifice 10 Oil Return Pipe 12 Connector 14 Hygroscopic Material 16 Condenser 17 Condenser Fan 20 Heat Exchange Fin 22 Heat Heater 24 Controller 26 capillary tubes

Claims (6)

[Claims] 1. In an accumulator in a refrigeration cycle that is circulated and connected to a compressor, a condenser, a decompression means, an evaporator and an accumulator via a refrigerant pipe, the tip of a refrigerant inlet pipe of the accumulator is arranged up to near the bottom of the accumulator container. A refrigerating method characterized in that the tip of the refrigerant outlet pipe is arranged near the ceiling in the accumulator container together with the refrigerant outlet pipe and the refrigerant outlet pipe are communicated with the oil return pipe or the capillary tube. Cycle accumulator structure. 2. The oil return pipe connecting the bottom portion of the accumulator container and the refrigerant outlet pipe is smaller in diameter than the refrigerant outlet pipe, has a relatively long length, and is excellent in heat conductivity. The structure of the accumulator of the refrigeration cycle according to claim 1. 3. The refrigerating cycle according to claim 2, wherein an oil return pipe connecting the bottom portion of the accumulator container and the refrigerant outlet pipe is installed near the condenser of the refrigerating cycle. Accumulator structure. 4. The structure of the accumulator for a refrigerating cycle according to claim 2, wherein a heater is attached to the outer circumference of an oil return pipe connecting the bottom of the accumulator container and the refrigerant outlet pipe. 5. The refrigeration cycle accumulator structure according to claim 1, wherein a hygroscopic material is disposed below the oil return pipe. 6. The oil return pipe has an inner diameter of 3 mm or more and a length of 50 cm or more, and is designed so that the capacity in the pipe is less than or equal to the capacity of the compressor.
The structure of the accumulator of the refrigeration cycle according to any one of 1 to 5.