A scroll compressor provided with a discharge muffler arrangement

Abstract

The scroll compressor includes a compressor shell having a discharge outlet; an orbiting scroll; a fixed scroll including a discharge passage (16); a discharge pressure volume (17) at least partially defined by the compressor shell and the fixed scroll (7); a discharge muffler arrangement (21) attached to the fixed scroll (7) and arranged in the discharge pressure volume (17), the discharge muffler arrangement (21) including a first tubular element (28) provided with a muffler inlet (29) fluidly connected to the discharge passage (16), an expansion chamber (33) fluidly connected to an inner volume of the first tubular element (28), and a second tubular element (35) including an inlet opening emerging in the expansion chamber (33) and an outlet opening fluidly connected to the discharge pressure volume (17).

Claims

1. A scroll compressor including: a compressor shell having a discharge outlet, an orbiting scroll arranged within the compressor shell and comprising an orbiting base plate and an orbiting spiral wrap extending from the orbiting base plate, a fixed scroll arranged within the compressor shell and comprising a fixed base plate and a fixed spiral wrap extending from the fixed base plate, the fixed and orbiting spiral wraps defining, with the fixed and orbiting base plates compression chambers, the fixed scroll further comprising a discharge passage which is formed in the fixed base plate, a discharge pressure volumeat least partially defined by the compressor shell and the fixed scroll, a discharge muffler arrangement attached to the fixed scroll and arranged in the discharge pressure volume, wherein the discharge muffler arrangement includes a first tubular element provided with a muffler inlet fluidly connected to the discharge passage, an expansion chamber fluidly connected to an inner volume of the first tubular element, and a second tubular element including an inlet opening emerging in the expansion chamber and an outlet opening fluidly connected to the discharge pressure volume.

2. The scroll compressor according to claim 1, wherein the first tubular element comprises a first tubular wall portion adjacent to the muffler inlet and delimiting an inlet chamber, and a second tubular wall portion comprising apertures opening into the expansion chamber.

3. The scroll compressor according to claim 1, wherein the first tubular element includes a first open end defining the muffler inlet and a second open end which is remote from the muffler inlet and which is fluidly connected to the discharge pressure volume.

4. The scroll compressor according to claim 3, wherein the second open end of the first tubular element opens into the discharge pressure volume.

5. The scroll compressor according to claim 1, wherein the outlet opening of the second tubular element opens into the discharge pressure volume.

6. The scroll compressor according to claim 1, wherein the discharge muffler arrangement includes an outlet chamber provided with a muffler outlet emerging in the discharge pressure volume.

7. The scroll compressor according to claim 3, wherein the second open end of the first tubular element opens into the outlet chamber.

8. The scroll compressor according to claim 6, wherein the outlet opening of the second tubular element opens into the outlet chamber.

9. The scroll compressor according to claim 6, wherein the muffler outlet is directed towards the discharge outlet provided on the compressor shell.

10. The scroll compressor according to claim 6, wherein the second tubular element is at least partially arranged in the outlet chamber.

11. The scroll compressor according to claim 6, wherein the discharge muffler arrangement includes a bottom wall, a side wall and an intermediate wall, the expansion chamber being delimited by the bottom wall, the side wall, the first tubular element and the intermediate wall.

12. The scroll compressor according to claim 11, wherein the discharge muffler arrangement includes a top wall, the outlet chamber being delimited by the top wall, the side wall and the intermediate wall, the intermediate wall separating the expansion chamber and the outlet chamber.

13. The scroll compressor according to claim 1, wherein the expansion chamber is annular and surrounds the first tubular element.

14. The scroll compressor according to claim 1, further including an intermediate part which fluidly connects the discharge passage formed in the fixed scroll with the muffler inlet in a continuous manner.

15. The scroll compressor according to claim 14, wherein the intermediate part is arranged in the discharge passage.

16. The scroll compressor according to claim 14, wherein the intermediate part includes a refrigerant guiding portion having an inner circumferential surface which converges towards the muffler inlet and which is configured to guide a compressed refrigerant gas flow, flowing through the discharge passage, towards the muffler inlet.

17. The scroll compressor according to claim 14, wherein the intermediate part includes a mounting portion in which is mounted a lower end portion of the first tubular element.

18. The scroll compressor according to claim 1, wherein the discharge muffler arrangement is made in one piece.

19. The scroll compressor according to claim 1, wherein the discharge muffler arrangement includes reinforcing structures provided on an outer surface of at least one muffler part of the discharge muffler arrangement, to further minimize vibration of said at least one muffler part and transmission of acoustic noise to the outside of the compressor shell.

20. The scroll compressor according to claim 6, wherein the second open end of the first tubular element opens into the outlet chamber.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The following detailed description of one embodiment of the invention is better understood when read in conjunction with the appended drawings being understood, however, that the invention is not limited to the specific embodiments disclosed.

[0065] FIG. 1 is a longitudinal section view of a scroll compressor according to a first embodiment of the invention.

[0066] FIG. 2 is a longitudinal section view of a discharge muffler arrangement of the scroll compressor of FIG. 1.

[0067] FIG. 3 is a front view of the discharge muffler arrangement of FIG. 2.

[0068] FIG. 4 is a perspective view of the discharge muffler arrangement of FIG. 2.

[0069] FIG. 5 is an enlarged view of a detail of FIG. 1.

[0070] FIG. 6 is a partial longitudinal section view of a scroll compressor according to a second embodiment of the invention.

DETAILED DESCRIPTION

[0071] FIG. 1 describes a scroll compressor 1 according to the invention occupying a vertical position.

[0072] The scroll compressor 1 includes a compressor shell 2 provided with a suction inlet 3 configured to supply the scroll compressor 1 with refrigerant to be compressed, and with a discharge outlet 4 configured to discharge compressed refrigerant. The discharge outlet 4 is advantageously provided on a side wall of an upper cap of the compressor shell 2.

[0073] The scroll compressor 1 further includes a support arrangement 5 fixed to the compressor shell 2, and a compression unit 6 arranged within the compressor shell 2 and supported by the support arrangement 5. The compression unit 6 is configured to compress the refrigerant supplied by the suction inlet 3. The compression unit 6 includes a fixed scroll 7, which is fixed in relation to the compressor shell 2, and an orbiting scroll 8 supported by and in slidable contact with a thrust bearing surface 9 provided on the support arrangement 5.

[0074] The fixed scroll 7 includes a fixed base plate 11 having a lower face oriented towards the orbiting scroll 8, and an upper face opposite to the lower face of the fixed base plate 11. The fixed scroll 7 also includes a fixed spiral wrap 12 projecting from the lower face of the fixed base plate 11 towards the orbiting scroll 8.

[0075] The orbiting scroll 8 includes an orbiting base plate 13 having an upper face oriented towards the fixed scroll 7, and a lower face opposite to the upper face of the orbiting base plate 13 and slidably mounted on the thrust bearing surface 9. The orbiting scroll 8 also includes an orbiting spiral wrap 14 projecting from the upper face of the orbiting base plate 13 towards the fixed scroll 7. The orbiting spiral wrap 14 of the orbiting scroll 8 meshes with the fixed spiral wrap 12 of the fixed scroll 7 to form a plurality of compression chambers 15 between them. Each of the compression chambers 15 has a variable volume which decreases from the outside towards the inside, when the orbiting scroll 8 is driven to orbit relative to the fixed scroll 7.

[0076] The fixed scroll 7 further comprises a discharge passage 16 which is formed in a central part of the fixed base plate 11 and which is fluidly connected to the compression chambers 15. The discharge passage 16 is also fluidly connected to a discharge pressure volume 17 defined by the compressor shell 2 and the fixed scroll 7.

[0077] Furthermore, the scroll compressor 1 includes a drive shaft 18 which extends vertically and which is configured to drive the orbiting scroll 8 in an orbital movement, and an electric driving motor 19, which may be for example a variable-speed electric driving motor, coupled to the drive shaft 18 and configured to drive in rotation the drive shaft 18 about a rotation axis A.

[0078] The scroll compressor 1 also includes a discharge muffler arrangement 21 arranged in the discharge pressure volume 17 such that a clearance is defined between the upper cap of the compressor shell 2 and an upper surface of the discharge muffler arrangement 21. Advantageously, the discharge muffler arrangement 21 is attached to the fixed scroll 7, and particularly to the fixed base plate 11, for example by use of screws or bolts. However, other suitable methods, e.g. welding, brazing or gluing may be applied to attach the discharge muffler arrangement 21 to the fixed scroll 7. The discharge muffler arrangement 21 may include a plurality of attachment tabs 22 which are secured to the fixed scroll 7.

[0079] The discharge muffler arrangement 21 includes a muffler body 23 having for example a globally cylindrical shape, and being made in one piece. The muffler body 23 may be manufactured in a polymer material compatible with the refrigerant and lubricant oil used in the scroll compressor 1, and which withstands the discharge temperatures occurring within the operating conditions of the scroll compressor 1. Advantageously, the muffler body 23 is made by molding or additive manufacturing methods.

[0080] The muffler body 23 includes a bottom wall 24, a top wall 25, also named top cover, opposite the bottom wall 24 and a side wall 26 connecting the bottom wall 24 to the top wall 25. The muffle body also includes an intermediate wall 27 arranged within an inner volume of the muffler body 23 defined by the bottom wall 24, the top wall 25 and the side wall 26. The intermediate wall 27 is particularly arranged between the bottom wall 24 and the top wall 25, and is substantially parallel to the bottom wall 24. According to the embodiment shown on the figures, the bottom wall 24 and the intermediate wall 27 extend horizontally.

[0081] The discharge muffler arrangement 21 also includes a first tubular element 28 having a first open end defining a muffler inlet 29 fluidly connected to the discharge passage 16, and a second open end which is remote from the muffler inlet 29. The first tubular element 28 may have a circular cross-section.

[0082] The first tubular element 28 particularly comprises a first tubular wall portion 28.1 adjacent to the muffler inlet 29 and delimiting an inlet chamber 31, and a second tubular wall portion 28.2 comprising apertures 32. Advantageously, the first tubular element 28 extends downwardly from a lower face of the intermediate wall 27 and protrudes from a lower face of the bottom wall 24.

[0083] The discharge muffler arrangement 21 further includes an expansion chamber 33 delimited by the bottom wall 24, the side wall 26, the first tubular element 28 and the intermediate wall 27. The expansion chamber 33 is fluidly connected to an inner volume of the first tubular element 28 via the apertures 32 which open into the expansion chamber 33. Advantageously, the expansion chamber 33 is annular and surrounds the first tubular element 28.

[0084] Furthermore, the discharge muffler arrangement 21 includes an outlet chamber 34 delimited by the top wall 25, the side wall 26 and the intermediate wall 27 of the muffler body 23. The outlet chamber 34 is located above the expansion chamber 33, and the intermediate wall 27 separates the outlet chamber 34 from the expansion chamber 33.

[0085] As better shown on FIG. 2, the second open end of the first tubular element 28 opens into the outlet chamber 34, and the discharge muffler arrangement 21 includes a second tubular element 35 which is provided on the intermediate wall 27 and which fluidly communicates the expansion chamber 33 with the outlet chamber 34. The second tubular element 35 includes a first open end defining an inlet opening emerging in the expansion chamber 33, and a second open end defining an outlet opening emerging in the outlet chamber 34.

[0086] According to the embodiment shown on the figures, the second tubular element 35 has a circular cross-section, is arranged in the outlet chamber 34, and extends upwardly from the upper face of the intermediate wall 27. Advantageously, the first tubular element 28 and the second tubular element 35 extend vertically.

[0087] The outlet chamber 34 is provided with a muffler outlet 36 emerging in the discharge pressure volume 17 at a predetermined separating distance from the discharge outlet 4 to allow communication between the discharge pressure volume 17 and a compressed refrigerant gas flow emerging from the muffler outlet 36. Advantageously, the muffler outlet 36 is directed towards the discharge outlet 4 provided on the compressor shell 2.

[0088] According to the embodiment shown on the figure, the discharge muffler arrangement 21 includes reinforcing structures 37, e.g. reinforcement ribs, provided on an outer surface of at least one muffler part of the discharge muffler arrangement 21, e.g. on outer surfaces of the top wall 25, the bottom wall 24 and/or the side wall 26, to further minimize vibration of said at least one muffler part and transmission of acoustic noise to the outside of the compressor shell 2.

[0089] The scroll compressor 1 further includes an intermediate part 38 which fluidly connects the discharge passage 16 formed in the fixed scroll 7 with the muffler inlet 29 in a continuous manner. According to the embodiment shown on the figures, the intermediate part 38 has a ring shape and is arranged, for example firmly fitted, in the discharge passage 16. Particularly, the intermediate part 38 includes: [0090] a refrigerant guiding portion 38.1 having an inner circumferential surface which converges towards the muffler inlet 29 and which is configured to guide a compressed refrigerant gas flow, flowing through the discharge passage 16, towards the muffler inlet 29, and [0091] a mounting portion 38.2 in which is mounted, for example sealingly mounted, a lower end portion of the first tubular element 28, and particularly of the first tubular wall portion 28.1.

[0092] The operation of the scroll compressor 1 will now be described.

[0093] When the scroll compressor 1 according to the invention is turned on, the orbiting scroll 8 is driven by the drive shaft 18 following an orbital movement, this movement of the orbiting scroll 8 causing an intake and compression of refrigerant in the compression chambers 15. The compressed refrigerant gas flow exits the compression unit 6 through the discharge passage 16 formed in the central part of the fixed scroll 7, and enters the discharge muffler arrangement 21 via the muffler inlet 29. Then, a first part of the compressed refrigerant gas flow, entering the discharge muffler arrangement 21, flows through the first tubular element 28, enters the outlet chamber 34 and exits the discharge muffler arrangement 21 via the muffler outlet 36. A second part of the compressed refrigerant gas, entering the discharge muffler arrangement 21, enters the expansion chamber 33 via the apertures 32 provided on the first tubular element 28, expands in the expansion chamber 33, enters the outlet chamber 34 via the second tubular element 35, and exits the discharge muffler arrangement 21 via the muffler outlet 36. Said first and second part of the compressed refrigerant gas flow are then directed towards the discharge outlet 4, provided on the compressor shell 2, by the muffler outlet 36.

[0094] Such a configuration of the discharge muffler arrangement 21 provides an improved acoustic noise damping through scattering, reflections and interference of sound waves within the discharge muffler arrangement 21, while reducing the pressures losses within the discharge muffler arrangement 21.

[0095] Also hereby, a more smooth and direct flow from the discharge muffler arrangement 21 towards the discharge outlet 4 with minimized turbulences and pressure losses is created, which contributes to further improve the efficiency of the scroll compressor 1. Further, the relatively hot and pulsating compressed refrigerant gas flow is prevented from directly hitting the inner surface of the upper cap of the compressor shell 2, thereby further reducing the acoustic noise generated by the scroll compressor 1 and reducing the outer surface temperature of said upper cap.

[0096] FIG. 6 discloses a scroll compressor 1 according to a second embodiment of the invention which differs from the first embodiment shown on FIGS. 1 to 5 essentially in that the discharge muffler arrangement 21 is devoid of an outlet chamber, and in that the second open end of the first tubular element 28 opens into the discharge pressure volume 17 and the outlet opening of the second tubular element 35 opens into the discharge pressure volume 17.

[0097] According to such an embodiment of the invention, the expansion chamber 33 is delimited by the bottom wall 24, the side wall 26, the first tubular element 28 and the top wall 25.

[0098] Of course, the invention is not restricted to the embodiments described above by way of non-limiting examples, but on the contrary it encompasses all embodiments thereof.