FR2718833A1 - Accumulator for use in a refrigerator. - Google Patents

Abstract

The present invention relates to an accumulator. The accumulator of the invention comprises an enclosure (2) having a cavity (7) for receiving a mixture of refrigerant (8) and lubricant (10), an inlet tube (20) connected to the lower part of the 'enclosure, in fluid communication with the cavity and having an extension (23) positioned within the cavity and in the vicinity of the top of the enclosure, a discharge tube (22) connected to the top of the enclosure and in fluid communication with the cavity, and a lubricant recovery conduit (24) attached to the discharge tube or to the extension of the inlet tube for supplying lubricant separated from the refrigerant from the cavity to the exhaust tube. evacuation. The invention applies to a cooling system of a refrigerator.

Description

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  The present invention relates to an accumulator and, more particularly, an accumulator for use in a cooling system of a refrigerator, adapted to effectively recover a lubricant mixed in a refrigerant from an evaporator to a compressor. As is well known, a refrigerator performs a function of cooling or freezing by

  through a cooling cycle thereof.

  Typically, the cooling cycle consists of condensing compressed refrigerant by a compressor at a condenser and evaporating the condensed refrigerant at an evaporator so that cooling or freezing is accomplished by absorption of the evaporated heat. Therefore, the evaporator is commonly referred to as a cooler. In general, the refrigerant is returned to the compressor via an accumulator, which makes it possible to implement a series of cooling cycles. In such a cooling system, the accumulator is disposed between the evaporator and the compressor to maintain pressure

stabilized refrigerant.

  A typical accumulator is shown schematically in FIG. 1. The accumulator illustrated herein comprises an enclosure 2 having a cavity 7 for receiving a mixture of a refrigerant and a lubricant therein. An intake tube 4 and a discharge tube 6 are connected to lower and upper portions of the enclosure 2, respectively. The intake tube 4 is connected to an evaporator and the evacuation tube 6 is connected to a compressor. In addition, an extension of the intake tube 4 which extends into the cavity 7 of the chamber 2 is slightly

curved at the end.

  During operation of the refrigerator, the mixture of refrigerant and lubricant is injected into the cavity 7 from the evaporator via the intake tube 4 by the operating pressure of the compressor and strikes the upper internal surface of the chamber 2. At this moment, a

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  substantial amount of the refrigerant becomes gaseous and is then sucked into the compressor via the discharge tube 6, while the remaining liquid refrigerant 8 is deposited on the bottom of the chamber 2. As described above, the accumulator serves effect as a gas / liquid separator for

  maintain the stability of the refrigerant pressure.

  On the other hand, in the cyclic cooling system, the lubricant 10 serves to lubricate the compressor and other parts, and flows through pipes together with the coolant 8. As previously indicated, a portion of the lubricant 10 is deposited on the bottom of the housing 2, in the form of an incomplete mixture with the liquid refrigerant 8. The intake tube 4 is provided with a lubricant recovery hole 12 to recover the lubricant 10 from the cavity 7 to it . Preferably, the hole 12 is formed in a lower portion of the extension of the intake tube 4. Part of the lubricant recovered in the intake tube 4 is sucked into the evacuation tube 6 through the cavity 7 function of refrigerant flow rate passing through the tube

  4 during the operation of the refrigerator.

  This recovery of the lubricant to the compressor can be obtained under the Bernoulli principle. However, the recovery efficiency of the lubricant is relatively low due to the existence of a space between the intake tube 4 and the discharge tube 6 and it is also

  dictated by the flow rate of the fluid.

  In addition, as shown in Figure 2, when the

  compressor operation is stopped during a sub-

  cooling of the refrigerator, the lubricant and the liquid refrigerant flow back into the intake tube 4 from the cavity 7 via the hole 12. At this time, the temperature of the refrigerator increases because the compressor is not actuated, which causes the partial and local vaporization of the refrigerant deposited in the cavity 7. As a result, the pressure of the fluid in the intake tube 4 fluctuates generating liquid membranes 14 having a layer

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  between the lubricant and the liquid refrigerant through the inner part of the intake tube 4. These membranes 14 are pushed upwards by the fluctuating pressure of the fluid due to the bubbling of the refrigerant 8 and, consequently, are progressively displaced towards the In this case, if the pressure of the fluid between the membranes 14 is greater than that of the liquid refrigerant in the cavity during the upward movement of the membranes 14, the gaseous refrigerant between the membranes 14 is introduced into the the liquid refrigerant 8 in the cavity 7 through the hole 12, which generates bubbles 18 causing bubbling noises. Also, the membrane 14 may burst when it escapes from the end end of the intake tube 4, which produces burst noises. When this occurs, splash and burst noises are generated only during periods of silence when the operation of the refrigerator is stopped, causing a nuisance to the user. Accordingly, it is an object of the present invention to provide an improved accumulator that is capable of efficiently recovering a lubricant mixed in a refrigerant to a compressor without creating bubbling and bursting noises when laying down the operation of the compressor.

compressor.

  The above objects as well as other objects of the present invention are achieved by providing an improved accumulator for use in a refrigerator, which comprises: an enclosure having a cavity for receiving a fluid mixture of a refrigerant and a a lubricant therein; an intake tube connected to a lower part of the chamber in fluid communication with the cavity and having an extension positioned in the cavity and in the vicinity of an upper part of the chamber; an evacuation tube connected to the upper part of the enclosure and in fluid communication with the cavity; and

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  a lubricant recovery conduit attached to the evacuation tube or extension of the intake tube for bringing lubricant separated from the fluid mixture from the

  cavity in the evacuation tube through this conduit.

  In accordance with a preferred embodiment of the present invention, the lubricant recovery conduit is a capillary tube. In addition, the lubricant recovery duct may comprise a loop or lace provided at its lower end. The discharge tube may also include a ring-shaped sleeve fitted therein, the sleeve having a recess formed on its outer periphery for retaining the lubricant recovery conduit therein. The intake tube may further include a clamp for coupling the recovery conduit

  of lubricant to the extension of the intake tube.

  The present invention is also directed to another embodiment of an accumulator for use in a refrigerator, which comprises: an enclosure having a cavity for receiving a fluid mixture of a refrigerant and a lubricant therein; an intake tube connected to an upper portion of the enclosure and in fluid communication with the cavity; and an evacuation tube connected to a lower portion of the enclosure in fluid communication with the cavity, and one end of the evacuation tube extending from the bottom of the enclosure to a top of a level

  predetermined of the fluid mixture contained in the cavity.

  According to another characteristic of the invention, the accumulator further comprises a lubricant recovery duct attached to the evacuation tube to bring the lubricant separated from the fluid mixture through this duct.

  from the cavity in the evacuation tube.

  This lubricant recovery duct may be constructed in the form of an inverted U-shaped tube, one end of which is disposed in the cavity and adjacent to the lower part of the enclosure and the other end of which is

located in the evacuation tube.

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  The inverted U-shaped tube may comprise a

  loop provided at its said first end.

  The above aims, features and advantages as well as other objects, features and advantages of the present invention will become more apparent in the course of

  the detailed description that follows, given with reference to

  attached drawings, in which: - Figure 1 is a sectional view of a conventional accumulator; FIG. 2 shows an operating state of the accumulator illustrated in FIG. 1; FIG. 3 is a sectional view of an accumulator according to a preferred embodiment of the present invention; Figures 4 and 5 show various fasteners of a lubricant recovery duct to a discharge tube and an intake tube respectively, of the accumulator illustrated in Figure 3; and - Figure 6 is a sectional view of another

  accumulator according to the present invention.

  Referring to Fig. 3, there is shown an accumulator suitable for use in a refrigerator according to a preferred embodiment of the present invention. The accumulator comprises an enclosure 2 having a cavity 7 for receiving a mixture of a refrigerant and a lubricant to be delivered from an evaporator (not shown), an intake tube 20 connected to a lower part of the chamber 2 and in fluid communication with the cavity 7, and a discharge tube 22 connected to an upper part of the chamber 2 and in fluid communication with the cavity 7. In addition, the inlet tube 20 is coupled to the evaporator and the discharge tube 22 is coupled to a compressor (not shown), respectively. The intake tube 20 has an extension 23 positioned in the cavity

  7 and in the vicinity of the upper part of the enclosure 2.

  The extension 23 of the intake tube 20 is slightly curved

at its end.

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  In such an accumulator, the mixture of refrigerant and lubricant ejected by the intake tube 20 collides against an upper inner surface of the enclosure 2 and is then sucked into the compressor in a substantial amount through the exhaust tube 22. by the operation of the compressor. Part of the mixture is deposited in the cavity 7. In particular, the liquid refrigerant and the lubricant are collected on the bottom of the enclosure. Also, the lubricant 10 is separated from the liquid refrigerant 8 and placed under the refrigerant 8 in the cavity 7 in a state of

incomplete mixture.

  As shown in FIG. 3, a lubricant recovery duct 24 is attached to the extension 23 of the intake tube 20 or to the evacuation tube 22, which duct 24 is able to bring the lubricant deposited on the bottom of the nozzle. enclosure 2 to the discharge tube 22. One end of the lubricant recovery conduit 24 is positioned inside the discharge tube 22 and its other end is disposed adjacent to the bottom of the enclosure 2 to submerge into the lubricant 10. The lubricant recovery duct 24 has a smaller diameter than the intake tube 20 and the evacuation tube 22. Preferably, the duct 24 may be a capillary tube which can suck therethrough lubricant deposited to the discharge tube 22. In this case, since the lubricant substantially fills the capillary tube 24, it can be immediately ejected into the discharge tube 22 during the energy supply of the ompresseur. Preferably, the conduit 24 may have a loop or hook 26 provided at its lower end, which is intended to prevent contaminating substances, sludge and the like deposited on

  the bottom of the enclosure 2 to enter this one.

  According to the accumulator of the present invention, when the compressor is not in use, the refrigerant 8 and the lubricant 10 can not flow back into the intake tube 20, which prevents the creation of the noises

bursting and bubbling.

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  On the other hand, when the compressor is energized, a flow of the gaseous refrigerant in the discharge tube 22 produces a reduced pressure above the capillary tube 24 in accordance with Bernoulli's principle, which causes the ejection of the lubricant. 10 deposited in the cavity 7 to the discharge tube 22 via the capillary tube 24, as well as its collection in the compressor. At this moment, the lubricant 10 is directly sucked into the evacuation tube 22 through the capillary tube 24 independently of the introduction of the refrigerant 8 into the evacuation tube 22, which substantially increases the efficiency of the lubricant recovery. to the compressor. Figures 4 and 5 show various embodiments of the attachment of the capillary tube 24 to the tube

  22 and the extension 23 of the intake tube 20.

  As illustrated in FIG. 4, an annular sleeve 28 is firmly fitted into the discharge tube 22 and has a recess 30 formed on its outer periphery for

  retain the capillary tube 24 in the recess.

  As shown in FIG. 5, the capillary tube 24 is fixed to the intake tube 20 by a clamp, jaw or clamp 32. Preferably, the collar 30 may have a groove 34 for retaining the capillary tube 24 therein. this. In addition, the capillary tube 24 can be attached to the intake tube 20 or the discharge tube 22 by a wire

or a strip of ribbon.

  Figure 6 shows another accumulator according to the present invention. In this embodiment, the intake tube 40 and the exhaust tube 42 are connected to the upper and lower portions of the enclosure 2, respectively, by reversing the conventional accumulator upside down. The intake and exhaust tubes 40, 42 at the

  times are in fluid communication with the cavity 7.

  The end end of the intake tube 40 is bent towards the wall of the enclosure 2. Also, the evacuation tube 42 extends from the bottom of the enclosure 2 to the top of a

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  predetermined level of the fluid contained in the cavity 7. In this accumulator, the refrigerant and the lubricant introduced into the cavity 7 through the inlet tube 40 are separated from each other so that the gaseous refrigerant is delivered to the compressor through the discharge tube 42, and the liquid refrigerant 8 and the lubricant are deposited on the bottom of the enclosure 2. On the other hand, the lubricant 10 is disposed under the liquid refrigerant 8 so that it exists an incomplete boundary layer formed

between them.

  As shown in FIG. 6, in order to recover the lubricant deposited in the cavity 7 towards the compressor, the evacuation tube 42 is provided with a lubricant recovery duct 44 in the form of an inverted U-tube, of which one end is located adjacent to the bottom of the enclosure 2 and whose other end is inserted into the discharge tube 42. Preferably, the inverted U-shaped tube 44 may have a loop 46 attached thereto, which can prevent impurities, contaminants and the like deposited on the bottom of the chamber 2 from entering the tube

evacuation 42.

  According to the other embodiment of the present invention as constructed above, during the power supply of the compressor, the gaseous refrigerant flows into the discharge tube 42, which generates a pressure difference between the cavity 7 and the tube

  discharge 42 due to the refrigerant flow rate.

  This allows the lubricant deposited in the cavity 7 to be sucked into the evacuation tube 42 with ease. Therefore, the recovery performance of the lubricant to

  the compressor is substantially increased.

  When the compressor is deactivated during a sub-

  cooling of the refrigerator, the supply of refrigerant 8 and lubricant 10 to the discharge tube 42 is interrupted. At this time, since the refrigerant and the lubricant deposited in the cavity 7 are completely separated from each other, they can not be

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  introduced into the evacuation tube 42 during the compressor pause. In addition, a reverse flow of refrigerant from the cavity 7 to the inlet tube 40 is fundamentally blocked due to the attachment of the inlet tube 40 to the upper part of the enclosure 2, which prevents the formation In the result, bubbling and bursting noises do not occur. In addition, when the liquid refrigerant is boiling in the cavity 7 due to an increase in temperature in the accumulator, the evaporated and expanded refrigerant can

  to escape into the evacuation tube 42.

  Although the invention has been described and illustrated with reference to preferred embodiments, it will be apparent to those skilled in the art that certain changes and modifications can be made without departing from the scope of the invention.

  of the spirit of the present invention.

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Claims (9)

  An accumulator for use in a refrigerator, which comprises: an enclosure (2) having a cavity (7) for receiving a fluid mixture of a refrigerant (8) and a lubricant (10) therein; an intake tube (4, 20) connected to a lower part of the chamber, in fluid communication with the cavity (7) and having an extension (23) positioned in the cavity and in the vicinity of an upper portion of the enclosure; and an evacuation tube (6, 22) connected to the upper part of the enclosure and in fluid communication with the cavity (7); characterized in that it further comprises a lubricant recovery conduit (24) attached to the evacuation tube (22) or extension (23) of the intake tube (20) for supplying the separated lubricant from the mixture fluid since the   cavity (7) to the evacuation tube and through this duct.   2. Accumulator according to claim 1, characterized in that said lubricant recovery duct (24) is a capillary tube.   3. Accumulator according to claim 1 or 2, characterized in that said lubricant recovery duct (24) comprises a loop (26) provided for its lower end.   4. Accumulator according to any one of   preceding claims, characterized in that said tube   discharge device (22) comprises an annular shaped sleeve (28) fitted therein, said sleeve having a recess (30) formed on its outer periphery to retain the   lubricant recovery (24) in the recess.   5. Accumulator according to any one of   preceding claims, characterized in that said tube   inlet (20) comprises a clamp (32) for 11 2718833   couple the lubricant recovery duct (24) to   the extension (23) of the intake tube.   An accumulator for use in a refrigerator, which comprises: an enclosure (2) having a cavity (7) for receiving a fluid mixture of a refrigerant (8) and a lubricant (10) therein; an intake tube (4, 40) and an evacuation tube (6, 42) connected to the enclosure (2) and in fluid communication with the cavity (7); characterized in that said intake tube (40) is connected to an upper part of the enclosure (2) and the discharge tube (42) is connected to a lower part of the enclosure (2), with a end of the evacuation tube extending from the bottom of the enclosure to above a predetermined level of the contained fluid mixture in the cavity.   Accumulator according to claim 6, characterized in that it further comprises a lubricant recovery duct (44) attached to the evacuation tube (42) for bringing the lubricant separated from the fluid mixture from the cavity (7).   to the evacuation tube (42) and through the conduit.   8. Accumulator according to claim 7, characterized in that said lubricant recovery duct (44) is constructed in the form of an inverted U-shaped tube, one end of which is disposed in the cavity (7) and adjacent to the portion lower part of the enclosure (2) and whose other end   is located in the evacuation tube (42).   9. Accumulator according to claim 8, characterized in that said tube (44) inverted U-shape comprises a   loop (46) provided at said first end thereof.