COMPRESSOR

Abstract

An electric-motor refrigerant compressor, for compressing a fluid, having a compressor housing having a housing bottom, and having a compressor part mounted in the compressor housing for conveying the fluid from a low pressure-side inlet to a high pressure-side outlet. The separating device is introduced into the housing bottom and has a cylindrical separating chamber which is connected to the outlet, and a separator which is arranged coaxially in said separating chamber for separating lubricant which is contained in the fluid, and a high pressure chamber of the compressor housing is coupled in flow terms by means of a passage duct to the separating chamber. The passage duct may be made in an intermediate wall between the high pressure chamber and the separating chamber in such a way that said passage duct opens into the separating chamber offset radially and on the outer side of the separator.

Claims

1. An electric-motor refrigerant compressor configured to compress a fluid comprising: a housing having a housing bottom; a compressor part mounted in the housing and configured to deliver the fluid from a low-pressure-side inlet to a high-pressure-side outlet; and a separating device inserted into the housing bottom, wherein the separating device includes a cylindrical separating chamber connected to the high-pressure-side outlet and a separator, wherein the separator is arranged coaxially in the separating chamber and configured to separate lubricant contained in the fluid from the fluid, wherein a high-pressure chamber of the housing is coupled in terms of flow to the separating chamber by a passage duct, wherein the passage duct is formed by an intermediate wall disposed between the high-pressure chamber and the separating chamber in such a way that the passage duct opens into the separating chamber in a manner offset radially with respect to a central center line of the separator, and wherein a clear width of the passage duct is less than or equal to a gap width of an annular gap formed between the separator and an inner wall of the separating chamber.

2. The electric-motor refrigerant compressor of claim 1, wherein the passage duct is positioned in such a way that the fluid flows into the separating chamber and tangentially to the separator.

3. The electric-motor refrigerant compressor of claim 1, wherein the passage duct is offset radially with respect to the central center line of the separator by an offset, wherein a sum of the offset and of the clear width of the passage duct is less than or equal to a radius of the separating chamber.

4. The electric-motor refrigerant compressor of claim 1, wherein the passage duct has an inner wall oriented parallel to an inflow direction of the fluid and/or perpendicularly to the housing bottom.

5. The electric-motor refrigerant compressor of claim 4, wherein the separating chamber is oriented radially with respect to the housing bottom, wherein the passage duct is elongated and extends in a radial direction.

6. The electric-motor refrigerant compressor of claim 1, wherein the passage duct is a slotted aperture in the intermediate wall.

7. The electric-motor refrigerant compressor of claim 6, wherein the slotted aperture has a substantially rectangular cross-sectional shape.

8. The electric-motor refrigerant compressor of claim 1, wherein the separating chamber is formed between an inner wall of the housing bottom and the high-pressure chamber and wherein the separating chamber projects at least partially into the high-pressure chamber.

9. The electric-motor refrigerant compressor of claim 1, wherein the housing bottom has an annular wall projecting axially beyond the separating chamber to form the high-pressure chamber, and wherein the passage duct is arranged within the annular wall so that the passage duct is radially offset from the center line of the separator towards the outlet.

10. The electric-motor refrigerant compressor of claim 9, wherein the compressor part lies along the annular wall.

11. An electric refrigerant compressor comprising: a housing including a housing bottom, an annular wall axially spaced apart from the housing bottom, and an intermediate wall extending from the annular wall, wherein the intermediate wall, the housing bottom, and the annular wall form a separating chamber; a compressor part disposed within the housing and configured to deliver a fluid from a low-pressure-side inlet to a high-pressure-side outlet, wherein the compressor part, the intermediate wall, and the annular wall form a high-pressure chamber; and a separator defining a center line and disposed in the separating chamber, wherein the intermediate wall defines a passage duct, and wherein the separator and passage duct are arranged relative to one another so that the passage duct is oblique to and radially spaced apart from the center line of the separator.

12. The electric refrigerant compressor of claim 11, wherein the passage duct includes a first inner wall, formed by the intermediate wall, and a second inner wall, formed by the annular wall, wherein the first inner wall is spaced apart from the second inner wall by a first distance, wherein an outer surface of the separator is spaced apart from the second inner wall by a second distance, wherein the first distance is less than or equal to the second distance.

13. The electric refrigerant compressor of claim 12, wherein the first inner wall is spaced apart from the center line of the separator by a third distance and wherein a radius of the separator chamber is a fourth distance, wherein a sum of the first distance and the third distance is less than or equal to the fourth distance.

14. The electric refrigerant compressor of claim 11, wherein the separating chamber extends at least partially into the high-pressure chamber.

15. An electric refrigerant compressor comprising: a housing including a housing bottom, an annular wall axially spaced apart from the housing bottom, and an intermediate wall extending from the annular wall, wherein the intermediate wall, the housing bottom, and the annular wall form a separating chamber; a compressor part disposed within the housing and configured to deliver a fluid from a low-pressure-side inlet to a high-pressure-side outlet, wherein the compressor part, the intermediate wall, and the annular wall form a high-pressure chamber; and a separator defining a center line and disposed in the separating chamber, wherein the intermediate wall defines a passage duct, and wherein the passage duct includes a first inner wall, formed by the intermediate wall, and a second inner wall, formed by the annular wall, wherein the first inner wall has a first length and the second inner wall has a second length, less than the first length.

16. The electric refrigerant compressor of claim 15, wherein the first inner wall is spaced apart from the second inner wall by a first distance, wherein an outer surface of the separator is spaced apart from the second inner wall by a second distance, wherein the first distance is less than or equal to the second distance.

17. The electric refrigerant compressor of claim 16, wherein the first inner wall is spaced apart from the center line of the separator by a third distance and wherein a radius of the separator chamber is a fourth distance, wherein a sum of the first distance and the third distance is less than or equal to the fourth distance.

18. The electric refrigerant compressor of claim 15, wherein the separating chamber extends between an outlet, formed by the bottom housing, and a lubricant reservoir, and wherein one end of the lubricant reservoir has a conical shape.

19. The electric refrigerant compressor of claim 15, wherein the passage duct is elongated and extends in a radial direction.

20. The electric refrigerant compressor of claim 19, wherein the passage duct has a rectangular cross-sectional shape.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] An illustrative embodiment of the invention is explained in greater detail below with reference to a drawing. In the drawing:

[0035] FIG. 1 shows a longitudinal section through a compressor having a housing and a compressor part and of a separating device on the housing bottom side,

[0036] FIG. 2 shows the compressor housing in a plan view, viewed in the direction of the bottom-side separating device, with a passage duct of slotted cross-sectional shape,

[0037] FIG. 3 shows the separating device and the flow path of a fluid through the passage duct and in the separating device in a sectional illustration along the line in FIG. 2, and

[0038] FIG. 4 shows the sectional illustration from FIG. 3 with a passage duct offset with respect to the center line of the separating device and without the flow path of the fluid in the separating device.

[0039] In all the figures, corresponding parts are in all cases provided with the same reference signs.

DETAILED DESCRIPTION

[0040] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

[0041] The compressor 2 illustrated in a sectional illustration in FIG. 1 for compressing a fluid F may be embodied as an electric-motor refrigerant compressor in a refrigerant circuit (not illustrated specifically) of an air-conditioning unit of a motor vehicle. The compressor 2 has a compressor housing 4 having a housing bottom 6 and a compressor part 8 mounted in the housing 4. The compressor part 8 has a first compressor element 8a, which is fixed relative to the compressor housing 4, and a moving second compressor element 8b, which engages therein and which is moved by shaft journals 10 and a motor shaft 12 by an electric motor (not illustrated specifically). Here, the compressor part 8 is embodied as a scroll compressor.

[0042] Within the compressor 2 there is a lubricant S, which is used to lubricate the compressor part 8 and performs a sealing function, thus avoiding leaks between the compressor elements 8a and 8b. Due to operating conditions, a refrigerant K and the lubricant S mix with the fluid F in this case.

[0043] The compressor housing 4 is embodied in the manner of a pot. The radial direction in relation to the compressor housing 4 and the axial direction perpendicular to the housing bottom 6 in the direction of the compressor part 8 are denoted in the adjacent direction diagram by R and A, respectively.

[0044] A separating device 14, which is connected to an outlet 16, is inserted into the housing bottom 6. The separating device 14 has a cylindrical separating chamber 18 and a hollow-cylindrical separator 20 arranged coaxially therein. The separating device 14 serves to separate the lubricant S contained in the fluid F into a lubricant reservoir 26 in the manner of a centrifugal separator. In the separating chamber 18, the fluid F flowing into the separating chamber 18 in an inflow direction E (FIG. 3) via a passage duct 27 flows around the separator 20 helically (in the manner of a cyclone) in the direction of the lubricant reservoir 26, wherein the centrifugal force acting on the refrigerant K contained in the fluid F and on the lubricant S contained in the fluid F acts as a separating mechanism. The refrigerant K separated from the lubricant S then flows out through the hollow-cylindrical separator 20 and the outlet 16 into the refrigerant circuit. In this context, the inflow direction E should be taken to mean the direction tangential to the separator 20 in which the fluid F flows into the separating chamber 18.

[0045] The separated lubricant S is fed back to the fixed compressor element 8b via a valve or restrictor 28 and via a lubricant duct 30. In this arrangement, the restrictor 26 is seated in the compressor housing 4. The returned lubricant S then flows via guide contours to rolling bearings 32 of the electric motor (not illustrated specifically) in order to lubricate and/or cool the bearings.

[0046] The axial direction of the separating device 14, i.e. the axial direction of the cylindrical separating chamber 18 and of the separator arranged coaxially therein, is denoted by X. The radial direction of the separating device 14 perpendicular to the inflow direction E and the radial direction of the separating device 14 parallel to the inflow direction E are denoted by Y and Z, respectively (FIG. 2).

[0047] Furthermore, the housing bottom 6 has an annular wall 34 projecting beyond the separating chamber 18. This divides the space surrounded by the fixed compressor part 8b and by the compressor housing 4 into an inner annular region 36 and into an outer annular region 38. A high-pressure chamber 40 is formed by the inner annular region 36, bounded by the housing bottom 6, the annular wall 34 and the compressor element 8b resting on the annular wall 34.

[0048] The separating chamber 18 is formed between an inner wall 41 of the housing bottom 6 and the high-pressure chamber 40, wherein the separating chamber 18 projects at least partially into the high-pressure chamber 40 in the axial direction A. The passage duct 27 couples the high-pressure chamber 40 to the separating chamber 18 in terms of flow. The passage duct 27 is introduced into an intermediate wall 44 between the separating chamber 18 and the high-pressure chamber 40 in such a way that the passage duct 27 opens into the separating chamber 18 in a manner offset along the radial direction Y of the separating device 14 with respect to the axial direction X of the separating device 14. In this case, the passage duct 27 is arranged in such a way in the inner annular region 36 of the annular wall 34 that the passage duct 27 is offset in the axial direction X of the separating device 14 or in the radial direction R of the compressor housing 4 toward the outlet.

[0049] On the low-pressure side of the compressor part 8, the fluid F flows into the compressor part 8 through an inlet 46. The compressor part 8, which in this case is a scroll compressor, compresses the fluid F in the manner of a positive displacement pump. The fluid F is compressed in a compressor part chamber 47 and then flows out of the compressor part 8 into the high-pressure chamber 40 through a high-pressure-side compressor part outlet 48.

[0050] FIG. 2 shows the pot-type compressor housing 4 with the compressor part 8 removed, looking at the housing bottom 6 of the compressor housing 4 along the axial direction A. The annular wall 34 projects beyond the separating device 14, forming the inner annular region 36 and the outer annular region 38. With the compressor part 8 (not illustrated in FIG. 2) and the housing bottom 6 of the compressor housing 4, the annular wall 34 forms the high-pressure chamber 40.

[0051] Furthermore, the compressor housing 4 has screw sockets 50 along a flange surface 49 to enable the compressor 2 to be fastened to a drive module (not illustrated), into which the motor of the compressor 2 is inserted. For the sake of greater clarity, only two screw sockets 50 are provided with a reference sign in FIG. 2.

[0052] The separating chamber 18 extends in the radial direction R with respect to the housing bottom 6 of the compressor housing 4. In this case, the passage duct 27 is offset in the radial direction R toward the outlet 16 of the separating chamber 18 in the inner annular region 36 and is of elongate shape along the axial direction X of the separating device 14. The passage duct 27 is embodied as a slotted aperture in the intermediate wall 44, wherein the aperture has a substantially rectangular cross-sectional shape. The cross-sectional shape of the passage duct 27 can be of slotted or oval design.

[0053] FIG. 3 shows the separating device 14 inserted into the housing bottom 6 of the compressor housing 4, looking toward the radially offset passage duct 27, in a sectional illustration along the line in FIG. 2. As is apparent, this passage is positioned in the intermediate wall 44 between the high-pressure chamber 40 and the separating chamber 18 in such a way that the fluid F delivered flows into the separating chamber 18 tangentially to the separator 20 in the inflow direction E.

[0054] In this case, the passage duct 27 has an inner wall 55, which is oriented tangentially to the inflow direction E of the fluid F in the passage duct 27. In this illustrative embodiment, the fluid F flows into the separating chamber 18 in such a way that both the inflow direction E and the inner wall 55 of the passage duct 27 are oriented perpendicularly to the housing bottom 6. That side of the inner wall 55 of the passage duct 27, the distance c (FIG. 4) of which from the radial direction or line Z, illustrated in dashed lines, of the separating device 14 parallel to the inflow direction E or, in this illustrative embodiment, perpendicular to the housing bottom 6 is shorter, is denoted by 55a (side closer to the axis). The opposite side of the inner wall 55 of the passage duct 27 is denoted by 55b (side remote from the axis).

[0055] The flow cross section, formed by the clear area of the passage duct 27, during the inflow of the fluid F from the high-pressure chamber 40 into the separating chamber 18 is matched to the operationally required fluid delivery volume. To avoid eddy formation of the flow of the fluid F in the separating chamber 18, the passage duct 27 is here matched to the operationally required delivery volume in such a way that the clear width a of the passage duct 27 may be smaller than the gap width b (a<b) of an annular gap 58 formed between the separator 20 and an inner wall 56 of the separating chamber 18. However, the clear width a can also be equal to the gap width b (a=b). Moreover, the passage duct 27 is of elongate shape along the axial direction X of the separating device 14. As a result, the fluid F flows tangentially into the annular gap 58 and is guided exclusively along one side of the separator 20, along an eddy-free path 60. Branching off of a second partial flow of the fluid F, indicated by the dashed arrows in FIG. 3, which would be guided along the separator 20 in the opposite direction of circulation from the eddy-free path 60 and would collide with the eddy-free path 60, is thereby avoided.

[0056] FIG. 4 shows, in the sectional illustration of FIG. 3, the separating device 14 inserted into the housing bottom 6, with the passage duct 27 having the clear width a and the gap formed by the inner wall 56 of the separating chamber 18 and the separator 20, having the gap width b.

[0057] To avoid unwanted eddy formation, the fluid F flows tangentially into the annular gap 58 formed between the separator 20 and the inner wall 56 of the separating chamber 18. As a consequence, the fluid F is guided selectively on only one side of the separator 20 along an eddy-free path 60 (FIG. 3). For this purpose, the passage duct 27 is in this illustrative embodiment offset along the radial direction Y of the separating device 14 relative to the center line X of the separating device 14 or relative to the center line X of the separator 20, wherein the offset c together with the clear width a of the passage duct 27 is less than or equal to the radius d of the separating chamber 18 or the inner wall 56 thereof, i.e. c+ad. In other words, the offset c is the distance between the radial direction Z of the separating device 14 parallel to the inflow direction E and that side 55a of the inner wall 55 of the passage duct 27 which faces the central center line X.

[0058] The invention is not restricted to the illustrative embodiments described above. On the contrary, other variants of the invention can be derived therefrom by a person skilled in the art without exceeding the subject matter of the invention. In particular, all the individual features described in conjunction with the illustrative embodiments can furthermore also be combined in different ways without departing from the subject matter of the invention.

[0059] While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.

LIST OF REFERENCE SIGNS

[0060] 2 compressor [0061] 4 compressor housing [0062] 6 housing bottom [0063] 8 compressor part [0064] 8a first compressor element [0065] 8b second compressor element [0066] 10 shaft journal [0067] 12 motor shaft [0068] 14 separating device [0069] 16 outlet [0070] 18 separating chamber [0071] 20 separator [0072] 26 lubricant reservoir [0073] 27 passage duct [0074] 28 restrictor [0075] 30 lubricant duct [0076] 32 rolling bearing [0077] 34 annular wall [0078] 36 inner annular region [0079] 38 outer annular region [0080] 40 high-pressure chamber [0081] 41 inner wall of the housing bottom [0082] 44 intermediate wall [0083] 46 inlet [0084] 47 compressor part chamber [0085] 48 compressor part outlet [0086] 49 flange surface [0087] 50 screw sockets [0088] 55 inner wall of the passage duct [0089] 55a side of the inner wall closer to the axis [0090] 55b side of the inner wall remote from the axis [0091] 56 inner wall of the separating chamber [0092] 58 annular gap [0093] 60 flow path of the fluid [0094] A axial direction of the compressor housing [0095] E inflow direction [0096] F fluid [0097] K refrigerant [0098] S lubricant [0099] M center line of the separator [0100] R radial direction of the compressor housing [0101] X axial direction/center line of the separating device [0102] Y radial direction of the separating device perpendicular to the inflow direction [0103] Z radial direction of the separating device parallel to the inflow direction [0104] a clear width [0105] b gap width [0106] c distance/offset [0107] d radius of the inner wall of the separating chamber