Scroll Compressor Provided With A Discharge Port Deflector

Abstract

The scroll compressor (1) includes a compressor shell (2) having a discharge outlet (4); a fixed scroll (7) arranged within the compressor shell (2) and including a fixed base plate (11) and a discharge passage (16) which is formed in the fixed base plate (11) and which is provided with a discharge port (17) emerging into a discharge pressure volume (18) at least partially defined by the compressor shell (2) and the fixed scroll (7); and a deflector (29) arranged in the discharge pressure volume (18), the deflector (29) covering the discharge port (17) and at least partially delimiting a discharge opening (31) facing the discharge outlet (4) of the compressor shell (2), the deflector (29) being configured to force a compressed refrigerant gas flow emerging from the discharge port (17) to smoothly shift from an axial direction to a radial direction and being configured to direct said compressed refrigerant gas flow towards the discharge outlet (4).

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims foreign priority benefits under 35 U.S.C. .sctn. 119 to French Patent Application No. 20/12478 filed on Dec. 1, 2020, the content of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] The invention relates to a scroll compressor provided with a deflector arranged in a discharge pressure volume delimited by a fixed scroll and a compressor shell.

BACKGROUND

[0003] JP 07189966 A shows a scroll compressor provided with a deflecting device arranged in a discharge pressure volume and configured to change the direction of a compressed refrigerant gas flow emerging from the compression chambers from a direction parallel to the longitudinal axis of the scroll compressor to a direction orthogonal to the longitudinal axis of the scroll compressor. By guiding the compressed refrigerant gas flow towards side walls of the discharge pressure volume, a direct impingement of the compressed refrigerant gas on the upper end wall surface of the compressor shell is avoided. Hence, pulsation noise is reduced.

[0004] As a discharge fitting is formed in the upper end wall of the compressor shell, the compressed refrigerant gas is subjected to additional changes in its flow direction before leaving the discharge pressure volume. This leads to significant pressure drop in the compressed refrigerant gas.

[0005] US 2019/0195224 A1 discloses a scroll compressor provided with a muffler attached to the fixed scroll base plate and covering a discharge port formed in the central portion of the fixed scroll. Also here, a direct flow of compressed refrigerant gas to the upper end wall of the compressor shell is avoided. However, this solution leads again to increased pressure drop in the compressed refrigerant gas, as several changes of the compressed refrigerant gas flow direction occur, before the compressed refrigerant gas leaves the muffler chamber through a discharge hole and flows towards the discharge outlet of the compressor shell.

SUMMARY

[0006] It is an object of the present invention to provide an improved scroll compressor, which can overcome the drawbacks encountered in conventional scroll compressors.

[0007] Another object of the present invention is to provide a scroll compressor with improved efficiency by reducing the pressure losses in the discharge pressure volume.

[0008] Another object of the present invention is also to reduce acoustic noise emitted from the compressor shell.

[0009] According to the invention such a scroll compressor includes:

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 and which is provided with a discharge port emerging into a discharge pressure volume at least partially defined by the compressor shell and the fixed scroll, and a deflector arranged in the discharge pressure volume, the deflector covering the discharge port and at least partially delimiting a discharge opening facing the discharge outlet of the compressor shell, the deflector being configured to force a compressed refrigerant gas flow emerging from the discharge port to shift, and advantageously to smoothly shift, from an axial direction to a radial direction and being configured to direct, and particularly to guide, said compressed refrigerant gas flow towards the discharge outlet.

[0010] As the deflector extends over the discharge port and is configured to direct the compressed refrigerant gas flow towards the discharge outlet, a direct impingement of the compressed refrigerant gas flow on an upper end wall of the compressor shell is avoided and the compressed refrigerant gas is not subjected to several changes in its flow direction before leaving the discharge pressure volume, which substantially reduces the pressures losses in the discharge pressure volume while suppressing pulsations and resonating waves between the compressor shell and the discharge port.

[0011] Consequently, the acoustic behavior and the efficiency of the scroll compressor according to the present invention are substantially improved compared to the acoustic behavior and the efficiency of the compressors of the prior art. Particularly, large improvements (up to -4 dB) have been observed, especially for frequencies at 2.5 kHz.

[0012] The scroll compressor may also include one or more of the following features, taken alone or in combination.

[0013] According to an embodiment of the invention, the discharge passage extends substantially parallel to the longitudinal axis of the scroll compressor.

[0014] According to an embodiment of the invention, the discharge passage is configured to fluidly connect the compression chambers to the discharge pressure volume.

[0015] According to an embodiment of the invention, the discharge port is provided at a central part of the fixed base plate of the fixed scroll.

[0016] According to an embodiment of the invention, the discharge outlet is provided on an upper cap of the compressor shell. Advantageously, the discharge outlet is provided on a side wall of said upper cap.

[0017] According to an embodiment of the invention, the deflector has an elbow shape.

[0018] According to an embodiment of the invention, the deflector is attached to the fixed base plate of the fixed scroll.

[0019] According to an embodiment of the invention, the deflector is attached to a base plate face of the fixed base plate facing away from the compression chambers.

[0020] According to an embodiment of the invention, the deflector includes a first end sealingly attached to the fixed base plate of the fixed scroll, and a second end at least partially delimiting the discharge opening.

[0021] According to an embodiment of the invention, the first end of the deflector is sealingly attached to the fixed base plate of the fixed scroll near the discharge port.

[0022] According to an embodiment of the invention, the discharge opening emerges into the discharge pressure volume at a predetermined separating distance from the discharge outlet to allow communication between the compressed refrigerant gas flow and the discharge pressure volume.

[0023] According to an embodiment of the invention, the scroll compressor further includes a discharge check valve assembly attached to the discharge outlet of the compressor shell and configured to prevent backflow of refrigerant from an external tubing of a refrigeration system into the discharge pressure volume, when the scroll compressor stops.

[0024] According to an embodiment of the invention, the discharge check valve assembly comprises a tubular valve housing having an inlet opening emerging into the discharge pressure volume and an outlet opening emerging outside the compressor shell and configured to be fluidly connected to the external tubing of a refrigeration system.

[0025] According to an embodiment of the invention, the discharge opening faces the inlet opening of the tubular valve housing and is located at a predetermined spacing distance from the inlet opening of the tubular valve housing.

[0026] According to an embodiment of the invention, a ratio between the cross-section of the inlet opening and the cross-section of the discharge opening is between 0.8 and 1.2, and for example between 0.9 and 1.1. In other words, the inlet opening of the tubular valve housing and the discharge opening are similar in size.

[0027] According to an embodiment of the invention, the discharge opening and the inlet opening are configured such that a majority of the compressed refrigerant gas leaving the discharge port of the fixed scroll is delivered directly into the inlet opening of the tubular valve housing. Such a configuration of the discharge check valve assembly and the deflector allows to reduce pressure losses in the compressed refrigerant gas flow.

[0028] According to an embodiment of the invention, the discharge passage includes a wall portion having a curved convex surface portion directed towards the discharge outlet, and advantageously towards the discharge check valve assembly and particularly towards the inlet opening of the tubular valve housing.

[0029] According to an embodiment of the invention, the deflector and the curved convex surface portion of the discharge passage define a smooth surface structure. Such a configuration of the deflector and the discharge passage allows to further reduce pressure losses. This is especially important when using low density refrigerants, e.g. low GWP refrigerants, as an increased volume flow is required to maintain a given cooling capacity.

[0030] According to an embodiment of the invention, the deflector includes an upper wall part having an inner deflecting surface portion which is concave and curved, the inner deflecting surface portion being directed towards the discharge outlet. Such a configuration of the discharge passage allows to further reduce pressure losses in the compressed refrigerant gas flow.

[0031] The deflector may be manufactured as sintered, pressed, punched, machined or molded metal component. Preferably, the deflector is made as a molded or 3D-printed plastic component.

[0032] Advantageously, the deflector is attached to the fixed scroll by use of screws or bolts. However, other suitable methods, e.g. welding, brazing, press fitting or gluing may be applied to attach the deflector to the fixed scroll.

[0033] These and other advantages will become apparent upon reading the following description in view of the drawing attached hereto representing, as non-limiting examples, embodiments of a scroll compressor according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The following detailed description of embodiments 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.

[0035] FIG. 1 is a longitudinal section view of a scroll compressor according to the invention.

[0036] FIG. 2 is a partial longitudinal section view of the scroll compressor of FIG. 1 showing a discharge check valve assembly in a closed position.

[0037] FIG. 3 is a partial longitudinal section view of the scroll compressor of FIG. 1 showing the discharge check valve assembly in an open position, and in which a discharge passage includes a wall portion having a chamfer.

[0038] FIG. 4 is a partial longitudinal section view of the scroll compressor of FIG. 1 showing the discharge check valve assembly in an open position, and in which the discharge passage includes a wall portion having a curved convex surface portion.

[0039] FIG. 5 is a partial top view of the scroll compressor of FIG. 1.

[0040] FIG. 6 is a perspective view of a deflector of the scroll compressor of FIG. 1.

DETAILED DESCRIPTION

[0041] FIG. 1 describes a scroll compressor 1 according to the invention occupying a vertical position.

[0042] 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.

[0043] The scroll compressor 1 further includes a support arrangement 5 fixed to the compressor shell 2, and a compression unit 6 disposed inside 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.

[0044] 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.

[0045] 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.

[0046] 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 extends parallel to the longitudinal axis of the scroll compressor 1, and is provided with a discharge port 17 emerging into a discharge pressure volume 18 defined by the compressor shell 2 and the fixed scroll 7. Therefore, the discharge passage 16 is configured to fluidly connect the compression chambers 15 to the discharge pressure volume 18.

[0047] Furthermore, the scroll compressor 1 includes a drive shaft 19 which extends vertically and which is configured to drive the orbiting scroll 8 in an orbital movement, and an electric driving motor 21, which may be for example a variable-speed electric driving motor, coupled to the drive shaft 19 and configured to drive in rotation the drive shaft 19 about a rotation axis A.

[0048] The scroll compressor 1 further includes a discharge check valve assembly 22 attached to the discharge outlet 4 and fluidly connected to the discharge pressure volume 18. The discharge check valve assembly 22 is particularly configured to prevent backflow of refrigerant from a high pressure side of a refrigeration system, into the discharge pressure volume 18, when the scroll compressor 1 stops.

[0049] The discharge check valve assembly 22 includes a tubular valve housing 23 inserted in the discharge outlet 4 of the compressor shell 2 and hermetically secured to the discharge outlet 4. The tubular valve housing 23 has a first end portion 23.1 arranged inside the discharge pressure volume 18 and provided with an inlet opening 24 emerging into the discharge pressure volume 18, and a second end portion 23.2 arranged outside the compressor shell 2 and provided with an outlet opening 25 emerging outside the compressor shell 2 and configured to be fluidly connected to an external tubing of the refrigeration system. According to the embodiments shown on the FIGS. 1 to 6, the second end portion 23.2 of the tubular valve housing 23 acts as a fitting to connect the external tubing of the refrigeration system.

[0050] The discharge check valve assembly 22 further includes a valve seat 26 located within the tubular valve housing 23 and formed at the inner surface of the tubular valve housing 23. The valve seat 26 is annular and extends around the inlet opening 24. Advantageously, the valve seat 26 is provided on the first end portion 23.1.

[0051] The discharge check valve assembly 22 also includes a valve member 27 arranged within the tubular valve housing 23 and movable between a closed position (see FIG. 2) in which the valve member 27 bears against the valve seat 26 and an open position (see FIG. 3) in which the valve member 27 is remote from the valve seat 26.

[0052] The discharge check valve assembly 22 further comprises a biasing element 28, such as a spring element, configured to bias the valve member 27 towards the closed position.

[0053] The scroll compressor 1 also includes a deflector 29 arranged in the discharge pressure volume 18 and covering the discharge port 17. The deflector 29 may be manufactured as sintered, pressed, punched, machined or molded metal component. However, the deflector 29 is preferably made as a molded or 3D-printed plastic component.

[0054] The deflector 29 includes a first end 29.1 sealingly attached to the upper face of the fixed base plate 11 of the fixed scroll 7 and located near the discharge port 17, and a second end 29.2 at least partially delimiting a discharge opening 31 facing the discharge outlet 4 of the compressor shell 2 and the inlet opening 24. According to the embodiments shown on the figures, the discharge opening 31 is delimited by the fixed base plate 11 of the fixed scroll 7 and the second end 29.2 of the deflector 29. However, the discharge opening 31 may for example by entirely delimited by the second end 29.2 of the deflector 29.

[0055] Advantageously, the deflector 29 is attached to the fixed scroll 7 by use of screws or bolts. However, other suitable methods, e.g. welding, brazing, press fitting or gluing may be applied to attach the deflector 29 to the fixed scroll 7.

[0056] According to the embodiments shown on the figures, the deflector 29 has an elbow shape and includes an upper wall part 32 having an inner deflecting surface portion which is concave and curved and which is directed towards the discharge outlet 4.

[0057] The deflector 29 is configured to direct a compressed refrigerant gas flow emerging from the discharge port 17 towards the discharge outlet 4, and particularly towards the outlet opening 25 of the tubular valve housing 23. The deflector 29 is also configured to force said compressed refrigerant gas flow to smoothly shift from an axial direction to a radial direction, with respect to the longitudinal axis of the scroll compressor.

[0058] According to the embodiments shown on the figures, the discharge opening 31 faces the inlet opening 24 of the tubular valve housing 23 and emerges into the discharge pressure volume 18 at a predetermined separating distance D1 from the discharge outlet 4 and is located at a predetermined spacing distance D2 from the inlet opening 24 of the tubular valve housing 23, to allow communication between the compressed refrigerant gas flow and the discharge pressure volume 18, and to ease mounting of the discharge check valve assembly 22 in relation to the deflector 29. The predetermined spacing distance D2 is between 2 and 40 mm, and advantageously between 10 and 30 mm. However, the discharge opening 31 and the inlet opening 24 are configured such that a majority of the compressed refrigerant gas leaving the discharge port 17 of the fixed scroll 7 is delivered directly into the inlet opening 24 of the tubular valve housing 23.

[0059] A ratio between the cross-section of the inlet opening 24 and the cross-section of the discharge opening 31 is between 0.8 and 1.2, and advantageously between 0.9 and 1.1, such that the inlet opening 24 of the tubular valve housing 23 and the discharge opening 31 are similar in size.

[0060] According to the embodiment shown on FIG. 4, the discharge passage 16 includes a wall portion 33 having a curved convex surface portion directed towards the inlet opening 24 of the tubular valve housing 23. Advantageously, the inner surface of the deflector 29 and the curved convex surface portion of the discharge passage 16 define a smooth surface structure. Such a configuration of the deflector 29 and the discharge passage 16 allows to further reduce pressure losses. This is especially important when using low density refrigerants, e.g. low GWP (Global Warming Potential) refrigerants, as an increased volume flow is required to maintain a given cooling capacity.

[0061] However, according to alternative embodiments of the invention, the discharge passage 16 may includes a wall portion 33 defined by a chamfer (see FIG. 3) or a wall portion 33 being cylindrical (see FIG. 2).

[0062] The operation of the scroll compressor 1 will now be described.

[0063] When the scroll compressor 1 according to the invention is turned on, the orbiting scroll 8 is driven by the drive shaft 19 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 exits toward the discharge pressure volume 18 via the discharge passage 16 and the discharge port 17 formed in the central part of the fixed scroll 7, is guided towards the inlet opening 24 of the tubular valve housing 23 by the deflector 29, moves the valve member 27 into the open position against the biasing force exerted by the biasing element 28, and then flows through the tubular valve housing 23 and the outlet opening 25 of the tubular valve housing 23.

[0064] Due to the configuration of the deflector 29, the wall portion 33 of the the discharge passage 16 and the inlet opening 24 of the tubular valve housing 23, pressure losses in the compressed refrigerant gas are significantly reduced, which significantly improves the efficiency and the performance of the scroll compressor 1.

[0065] When the scroll compressor 1 according to the invention is stopped, the biasing element 28 biases the valve member 27 toward the closed position, which prevents high-pressure refrigerant from returning to the discharge pressure volume 18.

[0066] 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.

[0067] While the present disclosure has been illustrated and described with respect to a particular embodiment thereof, it should be appreciated by those of ordinary skill in the art that various modifications to this disclosure may be made without departing from the spirit and scope of the present disclosure.

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 and which is provided with a discharge port emerging into a discharge pressure volume at least partially defined by the compressor shell and the fixed scroll, and a deflector arranged in the discharge pressure volume, the deflector covering the discharge port and at least partially delimiting a discharge opening facing the discharge outlet of the compressor shell, the deflector being configured to force a compressed refrigerant gas flow emerging from the discharge port to shift from an axial direction to a radial direction and being configured to direct said compressed refrigerant gas flow towards the discharge outlet; wherein the deflector has an elbow shape; wherein the deflector is attached to the fixed base plate of the fixed scroll; and wherein the deflector includes an upper wall part having an inner deflecting surface portion which is concave and curved, the inner deflecting surface portion being directed towards the discharge outlet.

2. (canceled)

3. (canceled)

4. The scroll compressor according to claim 1, wherein the deflector includes a first end sealingly attached to the fixed base plate of the fixed scroll, and a second end at least partially delimiting the discharge opening.

5. The scroll compressor according to claim 1, wherein the discharge opening emerges into the discharge pressure volume at a predetermined separating distance from the discharge outlet to allow communication between the compressed refrigerant gas flow and the discharge pressure volume.

6. The scroll compressor according to claim 1, further including a discharge check valve assembly attached to the discharge outlet of the compressor shell and configured to prevent backflow of refrigerant from an external tubing of a refrigeration system into the discharge pressure volume, when the scroll compressor stops.

7. The scroll compressor according to claim 6, wherein the discharge check valve assembly comprises a tubular valve housing having an inlet opening emerging into the discharge pressure volume and an outlet opening emerging outside the compressor shell and configured to be fluidly connected to the external tubing of a refrigeration system.

8. The scroll compressor according to claim 7, wherein the discharge opening faces the inlet opening of the tubular valve housing and is located at a predetermined spacing distance from the inlet opening of the tubular valve housing.

9. The scroll compressor according to claim 7, wherein a ratio between the cross-section of the inlet opening and the cross-section of the discharge opening is between 0.8 and 1.2, and for example between 0.9 and 1.1.

10. The scroll compressor according to claim 7, wherein the discharge opening and the inlet opening are configured such that a majority of the compressed refrigerant gas leaving the discharge port of the fixed scroll is delivered directly into the inlet opening of the tubular valve housing.

11. The scroll compressor according to claim 1, wherein the discharge passage includes a wall portion having a curved convex surface portion directed towards the discharge outlet.

12. The scroll compressor according to claim 11, wherein the deflector and the curved convex surface portion of the discharge passage define a smooth surface structure.

13. The scroll compressor according to claim 2, wherein the deflector includes a first end sealingly attached to the fixed base plate of the fixed scroll, and a second end at least partially delimiting the discharge opening.

14. The scroll compressor according to claim 3, wherein the deflector includes a first end sealingly attached to the fixed base plate of the fixed scroll, and a second end at least partially delimiting the discharge opening.

15. The scroll compressor according to claim 2, wherein the discharge opening emerges into the discharge pressure volume at a predetermined separating distance from the discharge outlet to allow communication between the compressed refrigerant gas flow and the discharge pressure volume.

16. The scroll compressor according to claim 3, wherein the discharge opening emerges into the discharge pressure volume at a predetermined separating distance from the discharge outlet to allow communication between the compressed refrigerant gas flow and the discharge pressure volume.

17. The scroll compressor according to claim 4, wherein the discharge opening emerges into the discharge pressure volume at a predetermined separating distance from the discharge outlet to allow communication between the compressed refrigerant gas flow and the discharge pressure volume.

18. The scroll compressor according to claim 2, further including a discharge check valve assembly attached to the discharge outlet of the compressor shell and configured to prevent backflow of refrigerant from an external tubing of a refrigeration system into the discharge pressure volume, when the scroll compressor stops.

19. The scroll compressor according to claim 3, further including a discharge check valve assembly attached to the discharge outlet of the compressor shell and configured to prevent backflow of refrigerant from an external tubing of a refrigeration system into the discharge pressure volume, when the scroll compressor stops.

20. The scroll compressor according to claim 4, further including a discharge check valve assembly attached to the discharge outlet of the compressor shell and configured to prevent backflow of refrigerant from an external tubing of a refrigeration system into the discharge pressure volume, when the scroll compressor stops.