WO2014059504A1

WO2014059504A1 - Expansion chamber for alternative compressor discharge line

Info

Publication number: WO2014059504A1
Application number: PCT/BR2013/000439
Authority: WO
Inventors: Cristiano STUMPF; Tadeu Tonheiro RODRIGUES; Eduardo Luis GAERTNER; Moacir Pirovano; Douglas NEGRI; Fábio Medeiros de LIMA
Original assignee: Whirlpool SA
Current assignee: Whirlpool SA
Priority date: 2012-10-18
Filing date: 2013-09-24
Publication date: 2014-04-24
Anticipated expiration: 2015-04-18
Also published as: BR102012026728A2; CN204716496U

Description

EXPANSION CHAMBER FOR ALTERNATIVE COMPRESSOR DISCHARGE

LINE

Field of the Invention

The present invention refers to an expansion chamber for alternative compressor discharge lines, preferably used in refrigeration systems.

The presently disclosed expansion chamber, into which two volumes are incorporated, further comprises an intermediate tube that due to its design is capable of optimizing attenuation of pulsations of an alternative compressor discharge cycles.

Background of the Invention

According to fundamental concepts corroborated by a wide range of specific technical literature, it is known that compressors comprise devices capable of altering the pressure of a working fluid (which usually circulates in any system, such as, for example, refrigeration system).

In the case of alternative compressors, the pressure of a working fluid is altered through a cyclic and controlled change in the volume of a compression chamber, which is usually defined by a chamber (or cylinder) capable of receiving a working fluid, and by a moving (piston) actuator capable of presenting alternative displacement within said compression chamber.

In this sense, most of moving elements of a compressor as well as the reaction exerted by said elements are responsible for producing vibration and noise. By this way, the present state of the art comprises a number of solutions intended to reduce vibration and noise. Within this context, expansion chambers which are specifically intended to decrease pressure fluctuations transmitted through alternative compressor discharge lines are already known.

Generally speaking, the already existing chambers comprise a type of chamber disposed at the alternative compressor discharge line, preferably arranged within the hermetic housing thereof.

The present state of the art is comprised of a wide range of constructions and designs of expansion chambers and among all of said constructions and designs there should be cited those expansion chambers containing two volumes fluidly connected to each other.

The main concept of said expansion chambers constituted by two volumes is intended to reaches higher levels of attenuation of discharge pulsation, occupying a physical space similar to the physical space of the expansion chamber comprising a single chamber.

In their simplest models, and as known from those skilled in the art, volumes of an expansion chamber (constituted by two volumes) are defined in one same body comprising in its interior a partition plate. Conventionally, said partition plate further comprises an orifice or a passage tube, this being responsible for connecting the two volumes of the expansion chamber.

Additionally, as far as said simplest models are concerned, it is commonly observed that an inlet tube, a passage tube (or orifice), and an outlet tube of an expansion chamber constituted by two volumes are roughly linearly aligned. Such alignment can be regarded as negative since after all same will define in certain situations (depending on the frequency of pulsations of discharge cycles ou depending on the operational capacity of the compressor) a single virtually continuous tube. Said virtually continuous tube allows for the inlet pulsation to be directly sent to the outlet tube of said expansion chamber constituted by two volumes, thus annulling a major portion of effects which mitigate pulsations of discharge cycles of an alternative compressor.

Examples of these simplest models of expansion chambers constituted by two volumes are described in US Patent 4,11 1 ,278.

The present state of the art further discloses other embodiments related to this matter discussed above, and among them there can be found the embodiments described in US Patent 5,196,654, US Patent 5,545,860, and JP Patent 1 1311 179.

Said US Patents 5,196,654 and 5,545,860 refer to expansion chambers constituted by two distinct volumes connected to each other by a passage tube. Nevertheless (and unlike said simplest models) an inlet tube, a passage tube and an outlet tube of the now analyzed expansion chambers then define a virtually L-arranged tube. Such an alignment can be considered as negative since in the end it presents the drawback that pressure measurement is too near the expansion chamber wall. Besides, the fact that said tubes are arranged in L- form prevents that some configurations for the length of the inlet/outlet tubes are made due to the interference between them. Furthermore, the feature that the tubes are disposed in L- form results in potential charge loss located at the L-curves, in addition to the fact that a virtually continuous tube can be formed.

In turn, JP Patent 11311179 refers to an expansion chamber also constituted by two distinct volumes which are fluidly connected to each other by a passage tube. Nevertheless, its inlet tube, its passage tube and its outlet tube then define a virtually U-arranged tube. Such alignment can be regarded as negative since after all the acoustic filter may not work due to the possibility that a virtually continuous tube is formed, in addition to the charge loss of two curves, which will increase the thermodynamic losses of the compressor.

Objects of the Invention

An object of the present invention is to provide an expansion chamber for alternative compressor discharge lines, which is capable of optimizing attenuation of the discharge cycles by creating barriers or obstacles directly aligned with discharge flow tubes.

Another object of the present invention is that said barriers or obstacles are simply produced. In this sense, a further object of the invention is that the elements constituting the expansion chamber can define barriers or obstacles capable of optimizing attenuation of pulsations of the discharge cycles.

Summary of the Invention

The above-mentioned objects are fully achieved by providing the presently disclosed expansion chamber for alternative compressor discharge line.

Said expansion chamber for alternative compressor discharge line, in accordance with the invention, comprises at least two volumes separated from one another by at least an inner plate; said volumes being fluidly connected to each other by at least a passage structure, and they are fluidly connected to the outer ambient by at least a passage structure.

In addition, said expansion chamber also comprises at least a barrier for nominal discharge flow of the alternative compressor, wherein sai|d barrier is substantially aligned with at least a passage structure of the volumes of said expansion chamber.

Preferably, said expansion chamber for the alternative compressor discharge line comprises at least a barrier for nominal flow from the passage structure. Said barrier, which can be disposed in the first volume, in the second volume, and in both, can be defined by the inner plate existing between said volumes, or it can also be defined by at least a baffle designed to in the interior of at least one of the volumes.

Furthermore, the passage structure of the inner plate comprises a tube, which can be horizontally or obliquely disposed.

Brief Description of the Drawings

The present invention is described in detail by means of figures listed below, wherein:

Figure 1 illustrates a schematic cut of a preferred embodiment of the expansion chamber for alternative compressor discharge lines in accordance with the present invention;

Figure 2 illustrates a schematic cut of the first optional embodiments of the expansion chamber for alternative compressor discharge lines in accordance with the present invention;

Figure 3 illustrates a schematic cut of the second optional embodiment of the expansion chamber for alternative compressor discharge lines in accordance with the present invention;

Figure 4 illustrates a schematic cut of the third optional embodiment of the expansion chamber for alternative compressor discharge lines in accordance with the present invention;

Figure 5 illustrates a schematic cut of the fourth optional embodiment of the expansion chamber for alternative compression discharge lines in accordance with the present invention; and

Figure 6 illustrates a schematic cut of the fifth optional embodiment of the expansion chamber for the expansion chamber for alternative compressor discharge lines rn aecbtd- ance with the present invention.

Detailed Description of the Invention

As known by those skilled in the art, alternative compressors and, more particularly alternative compressors used in refrigeration system are known to use expansion chamber capable of attenuating pressure fluctuations transmitted by means of their discharge lines.

In this context, an expansion chamber can be considered as a set of "volumes" arranged in series (or eventually in parallel) in a discharge line in order to attenuate discharge pulsations of the alternative compressors.

As known by those skilled in the art, there are a number of possibilities to position the tubes wh|ich connect the "volumes" within an expansion chamber as well to position the partition barrier of the volumes in order to attenuate determined frequency regions, depending on the used refrigerant gas and frequency of compressor functioning.

Therefore and as mentioned above, the present invention aims at optimizing dynamics of fluids travelling within an expansion chamber so as to further attenuate noise intrinsic to a compressor functioning.

Generally and in accordance with the present invention, such an optimization is not intended to alter arrangement, format or space of the "volumes" of said expansion chamber but rather creating in a simplified form at least a barrier to nominal discharge flow of the compressor which flows trough said "volumes" of the expansion chamber. It is worth mentioning that substantial alignment of said barrier(s) with at least a passage structure of the chamber is required.

Figs. 1 to 6 illustrate preferred embodiments of the present invention.

It should be pointed out that the main objective of all such embodiments comprises directing the nominal discharge flow FN to at least a barrier B before flowing outside the expansion chamber through an outlet flow FS of discharge. In this sense and as will become clear below, a barrier B can be defined at any inner surface of the expansion chamber, wherein the only reason for the definition of a barrier B resides in the fact that same should be substantially aligned with at least a passage structure, this being either the inlet of the expansion chamber itself or the fluid communication between the volumes of the expansion chamber.

Hence, the embodiments described in detail below are intended to provide means capable of generating at least a barrier B for the nominal discharge flow FN, thereby resulting in an outlet discharge flow FS with substantially attenuated pulsations and noise.

To this effect and in general terms, the expansion chamber in accordance with the present invention is formed of a first volume 1 and a second volume 2, wherein both is divided by an inner plate 3. Although the chamber format is not the crux of the present invention, it is worth mentioning that it can be essentially cylindrical, cubic, or further any prismatic format defined in accordance with each design. In this sense, it is then verified that the inner plate 3 can comprise a substantially discoid structure, substantially quadrangular, or further any format capable of delimiting the volume of the expansion chamber into at least two volumes.

Volume 1 comprises a passage structure 11 that is intended for the entry of the nominal discharge flow FN, and volume 2 comprises a passage structure 21 intended for the exit of the outlet discharge flow FS. The inner plate 3 in turn comprises a passage structure 31 (which can comprise a tube, an orifice, a channel, and the like) intended for fluid communication between volumes 1 and 2.

In the embodiments illustrated in Figs. 1 and 2, said passage structure 1 1 , passage structure 31 , and passage structure 21 are all of them not aligned.

Consequently, two barriers B are then defined, one at the inner plate 3 (specifically in the portion directly aligned with the passage structure 1 1 ) and the other at the body that defines the volume 2 (specifically in the portion directly aligned with the passage structure 31 ).

Further with regard to Figs. 1 and 2, it can be then verified that a nominal discharge flow FN undergoes a fir attenuation of pulsation in the barrier B defined at the inner plate 3. Said nominal discharge flow FN, when already altered, goes to the second volume 2 through the passage structure 31 of the inner plate 3, and designated passing flow FP. Said passing flow FP then undergoes further attenuation of pulsation in the barrier B defined in the body that defines said volume 2.

In the embodiment illustrated in Fig. 3, wherein the passage structure 1 1 and the passage structure 21 are aligned with one another and not aligned in relation to the passage structure 31 , only the nominal discharge flow FN undergoes attenuation of pulsation only in the second volume 2. This is due to the fact that said nominal discharge flow FN (it can be considered that in this embodiment the nominal discharge flow FN that enters the expansion chamber by the passage structure 1 1 of volume 1 is significantly similar to the discharge flow that flows to the volume 2. Further, in this embodiment, the nominal discharge flow FN is directly conveyed to volume 2 through the passage structure 31 of the inner plate 2) only contacts one barrier B defined in the body defining volume 2.

In the embodiment of Fig. 4 in which the passage structure 31 and passage structure 21 are aligned with one another and not aligned in relation to passage structure 11 , only the nominal discharge flow FN undergoes attenuation of pulsation still in the first volume. This stems from the fact that said nominal discharge FN only contacts one barrier B at the inner plate 3.

As in the embodiment of Fig. 5, the passage structure 31 of the inner plate is obliquely disposed and as a result same is not aligned with the passage structures 11 and 12. Hence and similarly to the embodiments illustrated in Figs. 1 and 2, there are two barriers B, one at the inner plate 3 (specifically in the portion directly aligned with the passage structure 11 ) and the other in the body defining volume 2 (specifically in the portion directly aligned with the passage structure 31 ).

With regard to the embodiment of Fig. 6, in which the passage structure 11 , the passage structure 31 and the passage structure 21 are all aligned with one another, one barrier B is defined on a baffle 4 that in said embodiment is disposed in the second volume 2 but it may also be disposed in the first volume 1 , or further in both volumes 1 and 2 of the expansion chamber.

Preferably, said bafflje 4 is a wall designed from the inner surface of the bbdy that defines one of the volumes of the expansion chamber. Optionally said baffle 4 can also be a wall designed from any of the surfaces of inner plate 3 (this optional arrangement is not illustrated but can be easily conceived from the context of the present invention).

Anyway all said described and illustrated embodiments achieve the same main objects, viz.: reducing pulsation of the compression discharged flow and reducing the noise generated by the compression discharge flow.

Evidently, the choice among one of the described and illustrated embodiments will depend on the design of the compressor in which the expansion chamber, in accordance with the present invention, is to be installed. This is because there are cases in which a single barrier B is sufficient; nevertheless, there are cases in which two or three barriers B are required due to the different work frequencies of each compressor.

In addition, it is important to point out that the descriptions and exemplifications above have as the sole object to describe in an exemplary form the preferred embodiments of the present invention.

Therefore, it is clear for those skilled in the art that the scope of the present invention can include further analogous and/or equivalent embodiments, the features of which are foreseeable and limited by the appended claims.

Claims

1. Expansion chamber for alternative compressor discharge line, comprising:

at least two volumes (1 , 2) separated from each other by at least one inner plate (3); said volumes (1 , 2) are fluidly connected to each other by at least one passage structure (31 ); and

each of said volumes (1 , 2) is fluidly connected to the outer ambient by at least one passage structure (11 , 21 );

the expansion chamber for alternative compressor discharge line is CHARACTERIZED in that it comprises:

at least one barrier (B) for tr)e discharge nominal flow (FN) of the alternative compressor; wherein the

barrier (B) is substantially aligned with at least one passage structure (1 1 , 31).

2. Expansion chamber, in accordance with claim 1 , CHARACTERIZED in that it comprises at least one barrier (B) for the nominal flow (FN) from the passage structure (1 1 ).

3. Expansion chamber, in accordance with claim 2, CHARACTERIZED in that the barrier (B) for the nominal flow (FN) from the passage structure (11 ) is defined by the inner plate (3).

4. Expansion chamber, in accordance with claim 2, CHARACTERIZED in that said barrier (B) for the nominal flow (FN) from the passage structure (11 ) is defined by at least one baffle (4) designed inside at least one of said volumes (1 , 2).

5. Expansion chamber, in accordance with claim 1 , CHARACTERIZED in that it comprises at least one barrier (B) for the nominal flow (FN) from the passage structure (31 ).

6. Expansion chamber, in accordance with claim 5, CHARACTERIZED in that said barrier (B) for the nominal flow (FN) from said passage structure (31 ) is defined by the inner surface of the wall of the expansion chamber that define the volume (2).

7. Expansion chamber, in accordance with claim 5, CHARACTERIZED in that said barrier (B) for the nominal flow (FN) from the passage structure (11 ) is defined by at least one baffle (4) designed inside of at least one of said volumes (1 , 2).

8. Expansion chamber, in accordance with claim 1 , CHARACTERIZED in that said passage structure (31 ) of the inner plate (3) comprises a tube.

9. Expansion chamber, in accordance with claim 8, CHARACTERIZED in that said passage structure (31 ) of the inner plate (3) comprises a tube that is horizontally disposed.

10. Expansion chamber, in accordance with claim 8, CHARACTERIZED in that said passage structure (31 ) of the inner plate (3) comprises a tube that is obliquely disposed.