JPH0539409Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an accumulator in a refrigeration system, and more specifically, the present invention relates to an accumulator in a refrigeration system, and more specifically, a compressor in a refrigeration system in which a compressor, a condenser, an expansion mechanism, and an evaporator are connected via refrigerant piping. The present invention relates to an accumulator in a refrigeration system that is installed on the suction side of a refrigerant and performs gas-liquid separation of refrigerant.

(Prior art) Generally, an accumulator that is installed on the suction side of a compressor in a refrigeration system and performs gas-liquid separation of refrigerant is shown in Japanese Utility Model Publication No. 51-28700, and is shown in Fig. 3. An inlet pipe B for guiding the refrigerant from the evaporator into the accumulator body container A is opened at the inner upper part of the accumulator main body container A, and an outlet pipe D for guiding the refrigerant in the accumulator main body container A to the compressor is opened. Passing near the inner bottom of the container A and opening at the inner top of the container A,
A first oil return hole E is provided in the wall of the outlet pipe D located near the bottom of the container A, and a first oil return hole E is provided at a distance in the wall of the outlet pipe D located higher than the oil return hole E. A second oil return hole F has been opened.

In this way, the oil accumulated in the container A flows from the first and second oil return holes E and F into the outlet pipe D together with the liquid refrigerant, and is supplied to the compressor. This compensates for the decrease in oil volume.
At this time, the liquid refrigerant flowing into the outlet pipe D generally evaporates within the outlet pipe D to become a gas refrigerant and is sucked into the compressor.

(Problem to be Solved by the Invention) By the way, when there is little liquid refrigerant stored in the container A, the oil collected in the lower part of the container A passes through the outlet pipe D from the first oil return hole E. It is then returned to the compressor. Furthermore, when the liquid refrigerant is further stored in the container A, the oil is located above the liquid refrigerant due to its specific gravity, so that the oil level is located above the first oil return hole E. In this case, oil enters the outlet pipe D from the second oil return hole F and is returned to the compressor.

However, depending on the size of the interval between the second oil return hole F and the first oil return hole E, the oil may not return to the compressor. That is, when the amount of oil in the compressor reaches the minimum oil amount necessary for lubrication, the amount of oil accumulated on top of the liquid refrigerant in the container A becomes the maximum amount, and at this time, the amount of oil accumulated on the liquid refrigerant in the container A becomes the maximum amount. When the distance between the holes E and F is greater than the height of the oil layer in the oil layer, when the liquid level of the liquid refrigerant is located directly above the upper edge of the first oil return hole E, the oil layer There are times when the upper surface of the container A is located below the second oil return hole F, and in such a case, the oil stored in the container A does not return to the compressor.

At this time, since the amount of oil in the compressor is the minimum amount of oil necessary for lubrication of the compressor, no oil returns to the compressor, resulting in an oil shortage that hinders the operation of the compressor. A problem arises that leads to

Incidentally, in the above-mentioned advertisement gazette showing the conventional example, there is a description that a plurality of the second oil return holes F may be provided, but in the case where a plurality of second oil return holes F are provided, each second oil return hole F...
The interval between them is not considered at all. In order to solve the above-mentioned problems, it is conceivable to provide a plurality of the second oil return holes F and to reduce the interval between them. However, if the interval becomes too small, the liquid A problem arises in that a large amount of refrigerant flows into the outlet pipe D and is not completely evaporated in the outlet pipe D, and a part of the refrigerant is sucked into the compressor as a liquid, causing liquid compression in the compressor. be.

The present invention was devised in view of the above problems, and its purpose is to reduce the amount of oil in the compressor when the amount of oil in the compressor reaches the minimum amount without causing liquid compression in the compressor.
To prevent burnout of the compressor by ensuring that oil can be returned to the compressor.

(Means for Solving the Problems) Therefore, in order to achieve the above object, the present invention provides a refrigerator comprising a compressor 1, a condenser 2, an expansion mechanism 3, and an evaporator 4 connected via refrigerant piping. This is an accumulator that is installed on the suction side of the compressor 1 in the apparatus to perform gas-liquid separation of the refrigerant, and has an inlet pipe 7 opened at the inner upper part of the accumulator main body container 6, and an outlet pipe 7. 8 is passed from the top of the container 6 near the inner bottom and opened to the inner top of the container 6, while an oil return hole 9 is opened in the pipe wall of the outlet pipe 8 located near the bottom of the container 6. At the same time, a difference C between the maximum amount of oil that can be filled into the compressor 1 and the minimum amount of oil required to lubricate the compressor 1 is recorded on the wall of the outlet pipe 8 located higher than the oil return hole 9. Maximum oil layer height L of oil accumulated in the container 6 obtained by dividing by the cross-sectional area m of the container 6 =
A plurality of auxiliary oil return holes 10 are opened at intervals approximately equal to C/m, and the height from the oil return hole 9 to the auxiliary oil return hole 10 located at the highest position.
H ₂ is higher than the height H ₁ = V/m obtained by dividing the maximum refrigerant amount V by the cross-sectional area m, and the height obtained by adding the maximum oil layer height L in the container 6 to the height H ₁ The number of each of the auxiliary oil return holes 10 is set within a range lower than H ₁ +L.
The number n obtained by dividing the height _H2 from to the auxiliary oil return hole 10 located at the top by the maximum oil layer height L
=H ₂ /L.

(Function) The auxiliary oil return holes 10 are connected to the outlet pipe 8 at intervals set based on the amount of oil in the accumulator body container 6 when the amount of oil in the compressor 1 reaches the minimum oil amount. A height H ₂ on the wall from the oil return hole 9 to the auxiliary oil return hole 10 located at the highest level.
Number n = H ₂ /L divided by the maximum oil layer height L
Therefore, regardless of the liquid level of the liquid refrigerant stored in the accumulator body container 6, the oil in the compressor 1 can be maintained while preventing the liquid refrigerant from returning to the compressor 1. When the amount of oil reaches the minimum amount required for lubrication of the compressor 1, the oil in the accumulator main body container 6 can be reliably returned to the compressor 1. That is, oil is always returned to the compressor 1 from any one of the plurality of auxiliary oil return holes 10 before the oil amount becomes less than the minimum oil amount.

(Example) The refrigeration system shown in FIG. 2 includes a compressor 1, an expansion mechanism 3 consisting of a condenser 2 and an expansion valve connected to the discharge side of the compressor 1, and an evaporator 4. Each device is connected via refrigeration piping. Further, an accumulator according to the present invention is connected to the suction side of the compressor 1.

Next, a first embodiment of the accumulator of the present invention will be described.
This will be explained based on the diagram.

The accumulator shown in Fig. 1 is a closed type,
and an accumulator main body container 6 having a cylindrical shape.
an inlet pipe 7 which is opened at the inner upper part of the main body container 6 and leads the refrigerant from the evaporator 4 into the accumulator main body container 6; and an outlet pipe 8 for guiding the gas refrigerant separated into gas and liquid in the container 6 to the compressor 1. An oil return hole 9 is formed in the pipe wall of the outlet pipe 8 located near the bottom of the container 6, and a plurality of auxiliary oil return holes 10 are provided in the pipe wall located at a higher level than the oil return hole 9. …
are opened in the length direction, that is, the height direction, of the outlet pipe 8 at the intervals described below.

That is, the amount of oil corresponding to the difference C between the maximum amount of oil that can be filled into the compressor 1 and the minimum amount of oil necessary for lubrication of the compressor 1 is the maximum amount of oil that can be stored in the container 6. In addition, the height L of the oil layer in the container 6 corresponding to this maximum oil amount is calculated by dividing the maximum oil amount by the cross-sectional area m of the container 6, L=C/m, and The distance between the holes 10 is made approximately equal to the maximum oil layer height L.

Further, the required number of the auxiliary oil return holes 10 to be opened in the wall of the outlet pipe 8 is determined as follows.

The maximum refrigerant amount V accumulated in the container 6 is the difference between the maximum refrigerant circulation amount and the minimum refrigerant circulation amount in the entire refrigeration system during cooling and heating operations, so the maximum refrigerant amount V in the container 6 is The liquid layer height H ₁ corresponding to is calculated by dividing the maximum refrigerant amount V by the cross-sectional area m of the container 6 V/m. The height _H2 from the hole 9 is higher than the liquid layer height _H1 ,
and the auxiliary oil return hole 10 is located at the liquid layer height _H1 .
interval, that is, the height of the sum of the maximum oil layer L
H _{1 <} H ₂ <H 1 +L within a range lower than H ₁ +L, and then the number n of the auxiliary oil return holes 10...
is calculated by n=H ₂ /L.

In this way, a required number of auxiliary oil return holes 10 corresponding to the refrigeration system are provided in the wall of the outlet pipe 8 located at a higher level than the oil return holes 9 necessary for lubrication of the compressor 1. height H ₂ that can be accommodated when the liquid refrigerant amount in the container 6 reaches the maximum refrigerant amount V at intervals set in consideration of the minimum oil amount.
, the amount of oil accumulated above the liquid refrigerant stored in the accumulator main body container 6 is equal to the difference between the maximum oil amount and the minimum oil amount of the compressor 1. When approaching, regardless of the liquid level height of the liquid refrigerant in the container 6, when the amount of oil in the compressor 1 reaches the minimum amount of oil necessary for lubrication of the compressor 1, Since the oil in the accumulator main body container 6 can be returned to the compressor 1, it is possible to reliably prevent oil from rising in the compressor 1, and therefore prevent the operation of the compressor 1 due to lack of lubricating oil. It will not cause any trouble.

Moreover, the auxiliary oil return holes 10 formed in the wall of the outlet pipe 8 are set at intervals equal to the maximum oil layer height L, and the number of them is increased from the oil return hole 9 to the maximum oil layer height L. In order to secure the minimum amount of oil necessary for lubrication of the compressor 1 by opening up to a height H ₂ that can correspond to when the amount of liquid refrigerant in the container 6 reaches the maximum amount V of refrigerant. Therefore, when the amount of oil in the compressor 1 reaches the minimum amount necessary for lubrication of the compressor 1, the oil in the accumulator body container 6 is reliably compressed. While the liquid refrigerant can be returned to the compressor 1, the amount of liquid refrigerant flowing into the outlet pipe 8 can be minimized, and liquid compression in the compressor 1 can be prevented.

(Effects of the invention) As described above, the present invention allows the inlet pipe 7 to be opened at the inner upper part of the main body container 6 of the accumulator, and the outlet pipe 8 to be passed from the upper part of the container 6 to near the inner bottom of the container 6. While opening inward at the top,
An oil return hole 9 is provided in the wall of the outlet pipe 8 located near the bottom of the container 6, and the compressor 1 is provided in the wall of the outlet pipe 8 located at a higher level than the oil return hole 9. The maximum oil layer height of the oil accumulated in the container 6 obtained by dividing the difference C between the maximum amount of oil that can be filled into the compressor 1 and the minimum amount of oil necessary for lubrication of the compressor 1 by the cross-sectional area m of the container 6. A plurality of auxiliary oil return holes 10 are opened at intervals approximately equal to L = C/m, and the height H ₂ from the oil return hole 9 to the auxiliary oil return hole 10 located at the top is Maximum refrigerant amount V
within a range that is higher than the height H ₁ =V/m obtained by dividing by the cross-sectional area m, and lower than the height H _{1 +} L that is the sum of the maximum oil layer height L in the container 6 to the height H 1 , each of the auxiliary oil return holes 10
... is the number obtained by dividing the height H ₂ from the oil return hole 9 to the auxiliary oil return hole 10 located at the top by the maximum oil layer height L (n = H ₂ /L). , regardless of the liquid level height of the liquid refrigerant stored in the accumulator main body container 6, the amount of oil in the compressor 1 is maintained at the compressor 1 while preventing the liquid refrigerant from returning to the compressor 1. The oil in the accumulator main body container 6 can be returned to the compressor 1 so that the amount of oil does not fall below the minimum oil amount required for lubrication of the compressor. Therefore, since the lubricating oil in the compressor 1 is prevented from running out, and the minimum number of auxiliary oil return holes 10 is provided,
It is also possible to prevent the liquid refrigerant from compressing the liquid in the compressor 1.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the inventive accumulator, FIG. 2 is a piping system diagram of a refrigeration system to which the inventive accumulator is applied, and FIG. 3 is a sectional view showing a conventional example. DESCRIPTION OF SYMBOLS 1... Compressor, 6... Accumulator main body container, 7... Inlet pipe, 8... Outlet pipe, 9... Oil return hole, 10... Auxiliary oil return hole.

Claims (1)

[Scope of utility model registration request] Compressor 1, condenser 2, expansion mechanism 3 and evaporator 4
This is an accumulator that is installed on the suction side of the compressor 1 in a refrigeration system in which the refrigerant is connected via refrigerant piping to perform gas-liquid separation of the refrigerant. , the inlet pipe 7 is opened, and the outlet pipe 8 is opened from the upper part of the container 6 through near the inner bottom part to the inner upper part of the container 6, while the outlet pipe 8 is located near the bottom part of the container 6. An oil return hole 9 is provided in the pipe wall of the outlet pipe 8 located at a higher level than the oil return hole 9. Maximum oil layer height L of oil accumulated in the container 6 obtained by dividing the difference C from the minimum amount of oil required for lubrication by the cross-sectional area m of the container 6 =
A plurality of auxiliary oil return holes 10 are opened at intervals approximately equal to C/m, and the height from the oil return hole 9 to the auxiliary oil return hole 10 located at the highest position.
H ₂ is higher than the height H ₁ = V/m obtained by dividing the maximum refrigerant amount V by the cross-sectional area m, and the height obtained by adding the maximum oil layer height L in the container 6 to the height H ₁ The number of each of the auxiliary oil return holes 10 is set within a range lower than H ₁ +L.
The number n obtained by dividing the height _H2 from the auxiliary oil return hole 10 located at the top by the maximum oil layer height L
= H ₂ /L.