SCROLL COMPRESSOR PROVIDED WITH A FLUID DEFLECTING AND DIVIDING DEVICE

The scroll compressor (2) includes an outer shell (4); a refrigerant suction inlet (7) formed in the outer shell (4) and configured to supply the scroll compressor (2) with refrigerant to be compressed; a compression unit (11) configured to compress refrigerant; a driving motor (21) configured to drive the compression unit (11) via a drive shaft (19); a fluid deflecting and dividing device (35) configured to divide a refrigerant suction flow entering the scroll compressor (2) through the refrigerant suction inlet (7) at least into a first flow (F1) and a second flow (F2). The fluid deflecting and dividing device (35) includes a first end (37) facing the refrigerant suction inlet (7) and a second end (38) which is closer to the compression unit (11) than the first end (37), the fluid deflecting and dividing device (35) being configured to guide the first flow (F1) towards the compression unit (11) and to guide the second flow (F2) towards the driving motor (21).

CROSS-REFERENCE TO RELATED APPLICATION

This application claims foreign priority benefits under U.S.C. § 119 to French Patent Application No. 17/55316 filed on Jun. 13, 2017, the content of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to a scroll compressor, and in particular to a hermetic scroll compressor.

BACKGROUND

U.S. Pat. No. 6,474,964 discloses a scroll compressor including:i. an outer shell delimiting a suction chamber,ii. a refrigerant suction inlet formed in the outer shell and configured to supply the scroll compressor with refrigerant to be compressed,iii. a compression unit configured to compress refrigerant,iv. a driving motor configured to drive the compression unit via a drive shaft,v. a fluid deflecting and dividing device configured to divide a refrigerant suction flow entering the scroll compressor through the refrigerant suction inlet at least into a first flow and a second flow, and is configured to deflect the first flow towards the center of the suction chamber where the refrigerant becomes laden with oil particles due to the presence of oil mist generating elements located in the suction chamber and to deflect the second flow towards the driving motor in order to cool at least parts of the driving motor, e.g. stator windings, rotor, magnets, etc., and where the second flow becomes also laden with oil particles.

Therefore, the second flow undergoes a certain pressure drop due to the flow through narrow passages through the driving motor, and the first flow also undergoes a certain pressure drop due to the configuration of the fluid deflecting and dividing device.

Hereby, the total pressure losses in the first and second flows are high, and the overall efficiency of the scroll compressor is thus low.

SUMMARY

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

Another object of the present invention is to provide a scroll compressor which has an improve efficiency while allowing to control the motor cooling.

According to the invention such a scroll compressor includes:i. an outer shell,ii. a refrigerant suction inlet formed in the outer shell and configured to supply the scroll compressor with refrigerant to be compressed,iii. a compression unit configured to compress refrigerant,iv. a driving motor configured to drive the compression unit via a drive shaft,v. a fluid deflecting and dividing device configured to divide a refrigerant suction flow entering the scroll compressor through the refrigerant suction inlet at least into a first flow and a second flow, characterized in that the fluid deflecting and dividing device includes a first end facing the refrigerant suction inlet, i.e. located in front of the refrigerant suction inlet, and a second end which is closer to the compression unit than the first end, the fluid deflecting and dividing device being configured to guide, i.e. deflect, the first flow towards the compression unit and to guide, i.e. deflect, the second flow towards the driving motor.

Such a configuration of the fluid deflecting and dividing device allows to directly guide the first flow towards the compression unit, and thus to substantially increase the efficiency of the scroll compressor.

Moreover, the fluid deflecting and dividing device according to the present invention induces lower frictional losses and less turbulences, and thus substantially reduces the pressure losses, which is especially important in scroll compressors using low density refrigerants (such as R134a) and high volume flow rate.

Further such a configuration of the fluid deflecting and dividing device ensures a control of the motor cooling depending on the positioning of the fluid deflecting and dividing device with respect to the refrigerant suction inlet and the driving motor.

Furthermore such a configuration of the fluid deflecting and dividing device ensures to control the percentage of refrigerant which is guided directly towards the compression unit and the percentage of refrigerant which is guided towards the driving motor depending on the height of the first end of the fluid deflecting and dividing device relatively to the refrigerant suction inlet.

In addition, such a configuration of the fluid deflecting and dividing device allows controlling the oil circulation rate, since a part of the refrigerant suction flow entering the scroll compressor is directly guided towards the scroll compressor.

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

According to an embodiment of the invention, the fluid deflecting and dividing device is configured such that the first flow is directly guided towards the compression unit.

According to an embodiment of the invention, the scroll compressor is a hermetic scroll compressor.

According to an embodiment of the invention, the refrigerant suction inlet emerges radially in an inner volume defined by the outer shell.

According to an embodiment of the invention, the first end and the second end are offset with respect to each other in an axial direction of the drive shaft, and are advantageously vertically offset with respect to each other.

According to an embodiment of the invention, the fluid deflecting and dividing device is stationary relative to the outer shell.

According to an embodiment of the invention, the fluid deflecting and dividing device includes an intermediate portion located between the first and second ends, the intermediate portion including a bottom plate and a plurality of blades protruding from the bottom plate. The presence of said blades improves the guiding and the spread of the first flow towards the compression unit, ensures a better repartition of the refrigerant inside the outer shell, and thus further improves the efficiency of the scroll compressor.

According to an embodiment of the invention, the blades of the plurality of blades diverge from each other towards the second end of the fluid deflecting and dividing device. Such a configuration of the blades ensures a circumferential guiding of the refrigerant inside the inner volume delimited by the outer shell, and ensures homogeneous velocities of the refrigerant through refrigerant apertures provided in the support frame which partially bears the compression unit.

According to an embodiment of the invention, each of the plurality of blades extends substantially up to the second end of the fluid deflecting and dividing device.

According to an embodiment of the invention, the plurality of blades include a plurality of main blades and a plurality of intermediate blades, each intermediate blade extending between two adjacent main blades and having a length smaller than a length of each the two adjacent main blades. Such a configuration of the blades ensures a homogenous repartition of the refrigerant inside the inner volume delimited by the outer shell, and thus limits the pressure drop in refrigerant apertures provided in the support frame.

According to an embodiment of the invention, each intermediate blade has an inwardly curved leading edge.

According to an embodiment of the invention, each main blade extends substantially from the first end of the fluid deflecting and dividing device, and each intermediate blade is offset from the first end of the fluid deflecting and dividing device.

According to an embodiment of the invention, the plurality of main blades includes two outer main blades and several inner main blades located between the two outer main blades, each of the two outer main blades having a height higher than a height of each of the inner main blades.

According to an embodiment of the invention, each of the two outer main blades protrudes from the first end of the fluid deflecting and dividing device and towards the refrigerant suction inlet.

According to an embodiment of the invention, the two outer main blades define two lateral edges of the fluid deflecting and dividing device.

According to an embodiment of the invention, the plurality of blades delimits diverging and upwardly extending flow channels.

According to an embodiment of the invention, each of the plurality of blades has a substantially constant thickness.

According to an embodiment of the invention, the bottom plate includes a curved guiding portion extending substantially from the first end of the fluid deflecting and dividing device, the curved guiding portion being configured to guide the first flow towards the second end of the fluid deflecting and dividing device. Such a configuration of the bottom plate ensures a smooth guiding of the first flow towards the compression unit

According to an embodiment of the invention, the scroll compressor further includes an inner shell surrounding the driving motor, the fluid deflecting and dividing device being secured to an outer surface of the inner shell. As the fluid deflecting and dividing device is not secured to the outer shell (which is the case for conventional scroll compressors) but to the inner shell, the distance between the refrigerant suction inlet and the fluid deflecting and dividing device is bigger. Thus securing the fluid deflecting and dividing device to the inner shell allows setting a high turning radius, which is lowering the pressure loss and lets some space to ensure a proper azimuthal distribution of the refrigerant.

According to an embodiment of the invention, the driving motor is entirely mounted inside the inner shell.

According to an embodiment of the invention, the bottom plate further includes a mounting portion having a shape substantially complementary to the outer surface of the inner shell.

According to an embodiment of the invention, the second end of the fluid deflecting and dividing device has a shape substantially complementary to the outer surface of the inner shell.

According to an embodiment of the invention, the inner shell is provided with a refrigerant inlet aperture facing the refrigerant suction inlet.

According to an embodiment of the invention, the refrigerant inlet aperture is partially covered by the fluid deflecting and dividing device. In other words, the fluid deflecting and dividing device is partially overlying the refrigerant inlet aperture.

In other words, the fluid deflecting and dividing device extends at least partially between the refrigerant inlet aperture and the refrigerant suction inlet.

According to an embodiment of the invention, the refrigerant inlet aperture is partially covered by the curved guiding portion of the fluid deflecting and dividing device.

According to an embodiment of the invention, the inner shell and the driving motor define a proximal chamber containing a first winding head of a stator, and a distal chamber containing a second winding head of the stator, the first winding head being closer to the compression unit than the second winding head and the second winding head being opposite to the first winding head.

According to an embodiment of the invention, the first winding head is formed by the portions of the stator windings extending outwardly from a first end face of a stator core, and the second winding head is formed by the portions of the stator windings extending outwardly from a second end face of the stator core opposite to the first end face.

According to an embodiment of the invention, the refrigerant inlet aperture emerges in the distal chamber.

According to an embodiment of the invention, the refrigerant inlet aperture is configured to fluidly connect the distal chamber and an annular volume delimited by the inner shell and the outer shell, the refrigerant suction inlet emerging in the annular volume.

According to an embodiment of the invention, the second end of the deflecting and dividing device extends over at least 120 degrees, and for example on approximately 180 degree, of the circumference of the inner shell.

According to an embodiment of the invention, the second end of the fluid deflecting and dividing device is curved, and advantageously extends along a circular arc, for example over at least 120 degrees, and preferably over about 180 degrees.

According to an embodiment of the invention, the second end of the fluid deflecting and dividing device has a radius of curvature substantially equal to a radius of curvature of the outer surface of the inner shell.

According to an embodiment of the invention, the scroll compressor further includes a support frame which bears at least partially the compression unit and which includes at least one refrigerant aperture, the fluid deflecting and dividing device being configured to guide the first flow towards the compression unit via the at least one refrigerant aperture provided on the support frame.

According to an embodiment of the invention, the fluid deflecting and dividing device is manufactured by 3D-printing.

According to an embodiment of the invention, the material used for 3D-printing the fluid deflecting and dividing device is chosen among ABS (Acrylonitrile Butadiene Styrene), PET (Polyethylene Terephthalate), PLA (Polylactic Acid), SLS Nylon, or any other suitable material for 3D printing (plastic or metallic).

According to an embodiment of the invention, the first end of the fluid deflecting and dividing device is substantially located at a same height than a central portion of the refrigerant suction inlet, and for example at a same height than a central axis of the refrigerant suction inlet.

According to an embodiment of the invention, the support frame includes several refrigerant apertures which are circumferentially distributed.

According to an embodiment of the invention, the compression unit includes a fixed scroll having a fixed base plate and a fixed spiral wrap, and an orbiting scroll having an orbiting base plate and an orbiting spiral wrap, the fixed spiral wrap and the orbiting spiral wrap forming a plurality of compression chambers.

According to an embodiment of the invention, the support frame includes a thrust bearing surface on which is slidably mounted the orbiting scroll.

According to an embodiment of the invention, the support frame includes an upper radial bearing for guiding the drive shaft.

According to an embodiment of the invention, the drive shaft includes a driving portion configured to drive the orbiting scroll in an orbital movement.

According to an embodiment of the invention, an upper end of the inner shell is secured to the support frame.

According to an embodiment of the invention, a lower end of the inner shell is secured to a centering member secured to the outer shell, the centering member being provided with a guide bearing configured to guide a lower end portion of the drive shaft.

According to an embodiment of the invention, a flow section of the refrigerant suction inlet includes a first flow section portion facing the fluid deflecting and dividing device, and a second flow section portion which is offset in the axial direction of the drive shaft, and for example vertically offset, from the fluid deflecting and dividing device. The second flow section portion may for example face the refrigerant inlet aperture.

In other words, the scroll compressor is configured so that an orthogonal projection of the fluid deflecting and dividing device on a reference plane which extends perpendicularly to a central axis of the refrigerant suction inlet is partially covering an orthogonal projection of the refrigerant suction inlet on said reference plane.

According to an embodiment of the invention, the first flow section portion represents from 20% to 80% of the flow section of the refrigerant suction inlet.

According to an embodiment of the invention, the first flow section portion faces the curved guiding portion of the fluid deflecting and dividing device.

According to an embodiment of the invention, the curved guiding portion of the fluid deflecting and dividing device has a scoop shape.

These and other advantages will become apparent upon reading the following description in view of the drawings attached hereto representing, as non-limiting example, one embodiment of a scroll compressor according to the invention.

DETAILED DESCRIPTION

FIG. 1shows a scroll compressor2, and particularly a hermetic scroll compressor, comprising a hermetic enclosure3comprising an outer shell4, an upper cap5and a baseplate6. As shown onFIG. 1, the outer shell4is cylindrical and includes an upper end closed by the upper cap5and a lower end closed by the baseplate6. According to the embodiment shown on the figures, the outer shell4has a constant diameter over its entire length.

The hermetic scroll compressor2further comprises a refrigerant suction inlet7provided on the outer shell4and configured to supply the hermetic scroll compressor2with refrigerant to be compressed, and a discharge outlet8configured to discharge compressed refrigerant. For example, the discharge outlet8may be provided on the upper cap5.

The hermetic scroll compressor2also comprises a support frame9arranged within the hermetic enclosure3and secured to the hermetic enclosure3, and a compression unit11also arranged within the hermetic enclosure3and disposed above the support frame9. The compression unit11is configured to compress the refrigerant supplied by the refrigerant suction inlet7, and includes a fixed scroll12, which is fixed in relation to the hermetic enclosure3, and an orbiting scroll13supported by and in slidable contact with a thrust bearing surface10provided on the support frame9.

The fixed scroll12includes a fixed scroll base plate14having a lower face oriented towards the orbiting scroll13, and an upper face opposite to the lower face of the fixed scroll base plate14. The fixed scroll12also includes a fixed spiral wrap15protruding from the lower face of the fixed scroll base plate14towards the orbiting scroll13.

The orbiting scroll13includes an orbiting scroll base plate16having an upper face oriented towards the fixed scroll12, and a lower face opposite to the upper face of the orbiting scroll base plate16and slidably mounted on the thrust bearing surface10. The orbiting scroll13also includes an orbiting spiral wrap17protruding from the upper face of the orbiting base plate16towards the fixed scroll12. The orbiting spiral wrap17meshes with the fixed spiral wrap15to form a plurality of compression chambers18between them. Each of the compression chambers18has a variable volume which decreases from the outside towards the inside, when the orbiting scroll13is driven to orbit relative to the fixed scroll12.

Furthermore the hermetic scroll compressor2includes a drive shaft19configured to drive the orbiting scroll13in an orbital movement, and a driving motor21, which may be a variable-speed driving motor, coupled to the drive shaft19and configured to drive in rotation the drive shaft19about a rotational axis A.

The driving motor21has a rotor22fitted on the drive shaft19, and a stator23disposed around the rotor22. The stator23includes a stator stack or stator core24, and stator windings wound on the stator core24. The stator windings define a first winding head25.1which is formed by the portions of the stator windings extending outwardly from a first end face24.1of the stator core24which is oriented towards the compression unit11, and a second winding head25.2which is formed by the portions of the stator windings extending outwardly from a second end face24.2of the stator core24which is opposite to the compression unit11.

The hermetic scroll compressor2further includes an inner shell26surrounding the driving motor21and in which the driving motor21is entirely mounted.

As shown inFIG. 1, the inner shell26and the driving motor21define a proximal chamber27containing the first winding head25.1of the stator23, and a distal chamber28containing the second winding head25.2of the stator23.

The inner shell26is further provided with a refrigerant inlet aperture29facing the refrigerant suction inlet7and emerging in the distal chamber28. The refrigerant inlet aperture29is configured to fluidly connect the distal chamber28and an annular volume31delimited by the inner shell26and the outer shell4.

According to the embodiment shown on the figures, an upper end of the inner shell26is secured to the support frame9, and a lower end of the inner shell26is secured to a centering member32secured to the outer shell4.

The hermetic scroll compressor2further includes an upper bearing member33provided on the support frame9and configured to cooperate with an outer circumferential wall surface of an upper end portion of the drive shaft19, and a lower bearing member34provided on the centering member32and configured to cooperate with an outer circumferential wall surface of a lower end portion of the drive shaft19. The lower bearing member34and the upper bearing member33are particularly configured to rotatably support the drive shaft19.

The hermetic scroll compressor2also includes a fluid deflecting and dividing device35secured to an outer surface of the inner shell26. Advantageously, the fluid deflecting and dividing device35extends at least partially between the refrigerant inlet aperture29and the refrigerant suction inlet7.

The hermetic scroll compressor2is configured so that an orthogonal projection of the fluid deflecting and dividing device35on a reference plane which extends perpendicularly to a central axis B of the refrigerant suction inlet7is partially covering an orthogonal projection of the refrigerant suction inlet7on said reference plane. In other words, the flow section of the refrigerant suction inlet7includes a first flow section portion7.1, i.e. an upper flow section portion, facing the fluid deflecting and dividing device35, and a second flow section portion, i.e. a lower flow section portion, which is vertically offset from the fluid deflecting and dividing device35and which particularly faces a lower portion of the refrigerant inlet aperture29. For example, the first flow section portion7.1represents from 20% to 80%, advantageously about 50%, of the flow section of the refrigerant suction inlet7.

The fluid deflecting and dividing device35is thus configured to divide a refrigerant suction flow, entering the hermetic scroll compressor2through the refrigerant suction inlet7, into a first flow F1and a second flow F2, and is further configured to guide the first flow F1directly towards the compression unit11, via several refrigerant apertures36which are provided on the support frame9and which are circumferentially distributed, and to guide the second flow F2towards the refrigerant inlet aperture29in order to cool at least parts of the driving motor21.

As better shown onFIGS. 2 to 5, the fluid deflecting and dividing device35includes a first end37facing the refrigerant suction inlet7and a second end38which is closer to the compression unit11than the first end37. Thus, the first end37and the second end38are vertically offset with respect to each other, and advantageously respectively form lower and upper edges of the fluid deflecting and dividing device35.

According to the embodiment shown on the figures, the first end37of the fluid deflecting and dividing device35is substantially located at a same height than a central portion of the refrigerant suction inlet7, and advantageously substantially at a same height than the central axis B of the refrigerant suction inlet7.

According to the embodiment shown on the figures, the second end38of the fluid deflecting and dividing device35is curved, and has a radius of curvature substantially equal to a radius of curvature of the outer surface of the inner shell26. Advantageously, the second end38of the fluid deflecting and dividing device35extends over at least 120 degrees, and for example on approximately 180 degree, of the circumference of the inner shell26.

The fluid deflecting and dividing device35further includes an intermediate portion39located between the first and second ends37,38. The intermediate portion39includes a bottom plate41comprising a curved guiding portion41.1extending from the first end37of the fluid deflecting and dividing device35, and a mounting portion41.2extending from the curved guiding portion41.1and up to the second end38. Advantageously, the mounting portion41.2has a shape substantially complementary to the outer surface of the inner shell26.

According to an embodiment of the invention, the curved guiding portion41.1partially covers the refrigerant inlet aperture29, and is particularly configured to guide the first flow F1towards the second end38of the fluid deflecting and dividing device35. The curved guiding portion41.1of the fluid deflecting and dividing device35may have for example a scoop shape. Advantageously, the first flow section portion7.1of the refrigerant suction inlet7faces the curved guiding portion41.1.

The intermediate portion39also includes a plurality of blades42respectively formed by wall portions protruding from the bottom plate41, and extending along the curved guiding portion41.1and the mounting portion41.2.

Advantageously, the blades42diverge from each other towards the second end38of the fluid deflecting and dividing device35, and delimit diverging and upwardly extending flow channels43. Particularly, the blades42include a plurality of main blades44and a plurality of intermediate blades45, each intermediate blade45extending between two adjacent main blades44and having a length smaller than a length of each the two adjacent main blades44.

According to the embodiment shown on the figures, each main blade44extends from the first end37of the fluid deflecting and dividing device35and up to the second end38of the fluid deflecting and dividing device35, and each intermediate blade45is offset from the first end37of the fluid deflecting and dividing device35and extends up to the second end38of the fluid deflecting and dividing device38. Advantageously, each intermediate blade45has an inwardly curved leading edge.

Such a configuration of the various blades42ensures a circumferential guiding of the refrigerant, from the first flow F1, inside the annular volume31, and a homogenous repartition of said refrigerant inside the annular volume31, and thus ensures homogeneous velocities of the refrigerant through the refrigerant apertures36provided on the support frame9.

According to the embodiment shown on the figures, the main blades44includes two outer main blades44.1defining two lateral edges of the fluid deflecting and dividing device35, and several inner main blades44.2located between the two outer main blades44.1. Advantageously, each of the two outer main blades44.1has a height higher than a height of each of the inner main blades44.2, and protrudes from the first end37of the fluid deflecting and dividing device35and towards the refrigerant suction inlet7.

The fluid deflecting and dividing device35may be manufactured by 3D-printing, and the material used for 3D-printing the fluid deflecting and dividing device is chosen among ABS (Acrylonitrile Butadiene Styrene), PET (Polyethylene Terephthalate), PLA (Polylactic Acid), SLS Nylon, or any other suitable material for 3D printing (plastic or metallic).

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