SCROLL MACHINE AND REFRIGERATION SYSTEM

Abstract

A scroll machine for a medium has a machine housing having a longitudinal axis and an inlet and an outlet for the medium. Provided in the machine housing along the longitudinal axis is: a drive unit having a drive shaft mounted on the machine housing by a first bearing unit and a second bearing unit, a first spiral unit having a spiral channel formed by a first spiral rib and has an inner end region and an outer end region, and a second spiral unit having a spiral channel formed by a second spiral rib and has an inner end region and an outer end region. The first spiral unit and the second spiral unit engage one another to form pressure chambers, wherein the first spiral unit can be moved by means of the drive shaft through the drive unit along an orbital path relative to the second spiral unit.

Claims

1. A scroll machine (2), in particular a spiral compressor, for a medium, in particular a refrigerant, having a machine housing (10) having a longitudinal axis (X) and an inlet and an outlet for the medium, wherein, provided in the machine housing (10) along the longitudinal axis (X) is a drive unit (400) having a drive shaft (420) which is mounted on the machine housing (10) by a first bearing unit (450) and a second bearing unit (300), a first spiral unit (100) having a spiral channel (120) which is formed by a first spiral rib (110) and has an inner end region (125) and an outer end region (126), a second spiral unit (200) having a spiral channel (220) which is formed by a second spiral rib (210) and has an inner end region (225) and an outer end region (226), and wherein the first spiral unit (100) and the second spiral unit (200) engage one another to form pressure chambers, wherein the first spiral unit (100) can be moved by means of the drive shaft (420) through the drive unit (400) along an orbital path relative to the second spiral unit (200), wherein the inlet (11) is in fluid communication with the outer end regions (126, 226) and the outlet (12) is in fluid communication with the inner end regions (125, 225), characterized in that the medium in the machine housing (10) can flow along a plurality of flow paths from the inlet (11) to the outer end regions (126, 226), and in that the drive shaft (420) has a hollow shaft portion (424) through which one of the flow paths extends.

2. The scroll machine (2) according to claim 1, characterized in that the hollow shaft portion (424) is formed by a blind hole, and in that the drive shaft (420) has at least one radial bore (428) which perforates the drive shaft (420) from the hollow shaft portion (424).

3. The scroll machine (2) according to claim 1, characterized in that a rotor (410) of the drive unit (400) is arranged between the first bearing unit (450) and the second bearing unit (300), and in that the drive shaft (420) has the at least one radial bore (428) between the first bearing unit (450) and the rotor (410) and/or between the second bearing unit (300) and the rotor (410).

4. The scroll machine (2) according to claim 3, characterized in that the drive unit (400) has at least one axial opening (414) and/or at least one axial groove (418), and in that the at least one axial opening (414) and/or the at least one axial groove (418) defines one of the flow paths.

5. The scroll machine (2) according to claim 1, characterized in that between inlet (11) and drive shaft (420) a flow path branches into two flow paths connected in parallel, one of the flow paths extending through the hollow shaft portion (424) and the other of the flow paths being guided through the first bearing unit (450).

6. The scroll machine (2) according to the preamble of claim 1, characterized in that the second bearing unit (300) and the first spiral unit (100) enclose a space (380) and in that at least one of the flow paths leads through the space (380).

7. The scroll machine (2) according to claim 1, characterized in that the second bearing unit (300) comprises a main bearing housing (302) and a main bearing body (305), and in that at least one of the flow paths extends through the main bearing housing (302) and/or the main bearing body (305).

8. The scroll machine (2) according to claim 6, characterized in that at least two flow paths coming from the inlet (11) lead through the second bearing unit (300) into the space (380), one of the flow paths extending through the main bearing body (305) and the other of the flow paths being guided through at least one entry opening (370) formed as a through-hole in the main bearing housing (302).

9. The scroll machine (2) according to claim 8, characterized in that a plurality of entry openings (370) are arranged around the circumference, preferably symmetrically.

10. The scroll machine (2) according to claim 6, characterized in that the drive shaft (420) projects into the space (380) and has a compensating mass (430) and/or an eccentric drive (150) in the space (380).

11. The scroll machine (2) according to claim 6, characterized in that the space (390) has at least one exit opening (390), and in that the exit opening (390) defines a flow path which connects the space (380) to the outer end regions (126, 226).

12. The scroll machine (2) according to claim 11, characterized in that the at least one exit opening (390) is provided as a radially oriented axial cut-out on the side facing the first spiral unit (100).

13. The scroll machine (2) according to claim 11, characterized in that the at least one exit opening (390) has a radially oriented first bore portion (392) and an axially oriented second bore portion (394).

14. The scroll machine (2) according to claim 11, characterized in that the at least one exit opening (390) is offset in the circumferential direction with respect to the at least one entry opening (370).

15. The scroll machine (2) according to claim 11, characterized in that the at least one exit opening (390), on the side facing the first spiral unit (100), opens partially or completely within a surface which is traversed when the first spiral unit (100) moves completely along the orbital path.

16. The scroll machine (2) according to claim 11, characterized in that the first spiral unit (100) has, on the side facing the at least one exit opening (390), a recessed portion (290) which is arranged within a surface and traverses the at least one exit opening (390) during a complete movement along the orbital path.

17. The scroll machine (2) according to claim 1, characterized in that a ring-pin coupling (350) is provided, and in that one of the flow paths is guided through the ring-pin coupling (350).

18. The scroll machine (2) according to claim 1, characterized in that the second spiral unit (200) is stationary.

19. The scroll machine (2) according to claim 1, characterized in that a high-pressure chamber (30) is arranged in the machine housing, in that the inner end regions (125, 225) are connected to the high-pressure chamber (30) via a passage (260) and are connected to the outlet (12) via the high-pressure chamber (30), and in that in the high-pressure chamber (30) a back-flow region (45) is provided which forces an S-shaped flow path in the high-pressure chamber (30).

20. The scroll machine (2) according to claim 1, characterized in that an intermediate bottom (50) is provided between the high-pressure chamber (30) and the second spiral unit (200) and in that the back-flow region (45) is formed by a recess (59) formed in the intermediate bottom (50) on the side facing the high-pressure chamber (30) and by a pressure connection piece (40) projecting toward the recess (59).

21. The scroll machine (2) according to claim 1, characterized in that the pressure connection piece (40) is in operative contact with the intermediate bottom (50) in a contact region (46) to form the back-flow region (45), and in that the contact region (46), on an imaginary connecting line, is arranged between the pressure connection piece (40) and the passage (260) in a plane perpendicular to the longitudinal axis (X).

22. The scroll machine (2) according to claim 1, characterized in that the pressure connection piece (40) comprises a bushing (49) with a non-return valve.

23. A refrigeration system (1) comprising a scroll machine (2) according to claim 1.

Description

[0057] Two exemplary embodiments of the present invention are described in detail below with reference to the accompanying figures, in which:

[0058] FIG. 1 is a highly simplified and schematic representation of a refrigeration system comprising a scroll machine according to the invention;

[0059] FIG. 2 is an enlarged, simplified sectional view of a first exemplary embodiment of the scroll machine according to FIG. 1;

[0060] FIG. 3 is an enlarged detailed view of the scroll machine according to FIG. 2;

[0061] FIG. 4 is an enlarged, simplified sectional view of the scroll machine according to FIG. 1;

[0062] FIG. 5 is a sectional view of the scroll machine along the section line B-B in FIG. 4; and

[0063] FIG. 6 is a sectional view of the scroll machine along section line A-A in FIG. 2.

[0064] Identical or functionally identical parts or features are identified with the same reference signs in the following detailed description of the figures. In addition, not all identical or functionally identical components are provided with a reference number in the figures.

[0065] FIG. 1 shows a preferred embodiment of a refrigeration system 1 comprising a scroll machine 2. The refrigeration system 1 comprises the scroll machine 2 designed as a scroll compressor, a condenser 3, an expansion element 4, and an evaporator 5. A medium, preferably a refrigerant, flows through the refrigeration system 1 in the direction indicated by arrows, first from an outlet 12 of the scroll machine 2 then, in sequence, to the condenser 3, the expansion element 4, the evaporator 5, and finally back through an inlet 11 into the scroll machine 2.

[0066] A preferred embodiment of the scroll machine 2 shown in FIG. 1 is described below with reference to FIGS. 2 to 5.

[0067] FIG. 2 is a simplified sectional view of the scroll machine 2 according to FIG. 1. The scroll machine 2 has a machine housing 10, which is designated as a whole and oriented along a longitudinal axis X. The machine housing 10 can have a plurality of housing parts, the machine housing 10 having a first housing part 10 and a second housing part 10 in the present exemplary embodiment.

[0068] From right to left, the inlet 11, a drive unit 400, a drive shaft 420, a first spiral unit 100, a second spiral unit 200, an intermediate bottom 50, a high-pressure chamber 30, and the outlet 12 are arranged in the machine housing 10 along the longitudinal axis X according to FIG. 2.

[0069] The first spiral unit 100 is coupled to the drive unit 400 via an eccentric drive 150 and the drive shaft 420.

[0070] The drive unit 400 preferably comprises an electric drive having a rotor 410 and a stator 415, the rotor 410 being rigidly coupled to the drive shaft 420.

[0071] The drive shaft 420 is oriented in the longitudinal axis X and the axis of rotation of the drive shaft 420 defines the longitudinal axis X in the exemplary embodiment shown. The drive shaft 420 has a first end portion and a second end portion on opposite sides in the longitudinal axis X.

[0072] In the first end portion, the drive shaft 420 is supported on the machine housing 10 by a first bearing unit 450 and in the second end portion by a second bearing unit 300. The rotor 410 of the drive unit 400 is arranged between the first bearing unit 450 and the second bearing unit 300.

[0073] The drive shaft 420 has a hollow shaft portion 424 which is oriented in the longitudinal X axis. The hollow shaft portion 424 can be designed as a blind hole and extends from a free end face of the drive shaft 420 in the first end portion toward the second end portion.

[0074] The drive shaft 420 also comprises a plurality of radial bores 428 which perforate the drive shaft 420 and connect the hollow shaft portion 424 to an outer lateral surface of the drive shaft 420.

[0075] According to FIG. 2, the drive shaft 420 can have at least one radial bore 428 between the first bearing unit 450 and the rotor 410 and/or between the second bearing unit 300 and the rotor 410. In the preferred embodiment shown, the drive shaft 420 has two radial bores 428 between the first bearing unit 450 and the rotor 410 and two radial bores 428 between the second bearing unit 300 and the rotor 410, which bores are arranged circumferentially symmetrically with respect to the drive shaft 420.

[0076] The first bearing unit 450 comprises a bearing holder 452 and a secondary bearing body 455. The bearing holder 452 can be formed by the machine housing 10. The secondary bearing body 455 can be designed as a roller bearing, which is preferably not sealed.

[0077] The first bearing unit 450 divides an interior of the machine housing 10 into an inlet portion and a drive portion, the inlet 11 opening into the inlet portion.

[0078] The inlet 11 is preferably arranged on an end face of the machine housing 10, with the inlet 11 even more preferably being arranged in alignment with the drive shaft 420preferably directlyupstream of the free end face of the drive shaft 420.

[0079] The second bearing unit 300 comprises a main bearing housing 302 and a main bearing body 305. The main bearing body 305 can be designed as a preferably unsealed roller bearing. The second bearing unit 300 further separates the interior of the machine housing 10 into the drive portion and a suction region 320.

[0080] The second bearing unit 300 has a first side and a second side, the first side being nearest the drive unit 400 and the second side being nearest the first spiral unit 100. The main bearing body 305 is arranged on the first side and an end face on the second side forms an axial bearing 190 for the first spiral unit 100.

[0081] The second bearing unit 300 or the main bearing housing 302 can be bell-shaped or cup-shaped and enclose a space 380 together with the first spiral unit 100.

[0082] The space 380 has a plurality of entry openings 370 which are arranged in the second bearing unit 300 or in the main bearing housing 302. The entry openings 370 perforate the main bearing housing 302 and open into the space 380. For example, the second bearing unit 300 can have four entry openings 370, which, as shown in FIG. 5, can be arranged circumferentially symmetrically on a lateral surface, preferably approximately centrally between the first side and the second side.

[0083] Furthermore, the space 380 can have a plurality of exit openings 390 which are preferably situated in the second bearing unit 300 or the main bearing housing 302. FIG. 3 shows an enlarged detailed view as shown in FIG. 2, from which it can be seen that the exit opening 390 can be formed from a first bore portion 392 and a second bore portion 394 in the main bearing housing 302.

[0084] The first bore portion 392 is oriented substantially radially and extends from the space 380. For manufacturing reasons, it can be advantageous for the first bore portion 392 to penetrate the main bearing housing 302 completely.

[0085] The second bore portion 394 is oriented substantially axially and connects the second side of the second bearing unit 300 or the main bearing housing 302 to the first bore portion 392.

[0086] The second bearing unit 300 can have four exit openings 390, which are preferably arranged circumferentially symmetrically. Furthermore, the exit openings 390 can be offset in the circumferential direction relative to the entry openings 370as indicated in FIG. 5.

[0087] With further reference to FIG. 2, it can be seen that the drive shaft 420 projects into the space 380 through the second bearing unit 300 or through the main bearing body 305. A compensating mass 430 arranged on the drive shaft 420 is located in the space 380.

[0088] Furthermore, it can be seen from FIG. 2 that the eccentric drive 150 is arranged in the space 380 and comprises an eccentric shaft portion 152 and an eccentric bearing body 155 arranged on the eccentric shaft portion 152. The eccentric shaft portion 152 can be formed by the drive shaft 420.

[0089] The first spiral unit 100 according to FIG. 2 has a first side 101 and has a second side 102 which is opposite the first side 101 in the longitudinal axis X. On the first side 101, the first spiral unit 100 is supported on the second bearing unit 300 by means of the axial bearing 190. The eccentric drive 150 is coupled to the first spiral unit 100 on the first side 101 and, on the second side 102, a first spiral rib 110 is arranged which protrudes along the longitudinal axis X and forms a first spiral channel 120.

[0090] A ring-pin coupling 350 is also provided, which comprises a plurality of ring-pin coupling pairs 351 (see FIG. 4 or 5). The ring-pin coupling pairs form the ring-pin coupling 350 which prevents full rotation of the first spiral unit 100 about the longitudinal axis X. The ring-pin coupling 350 couples the first spiral unit 100 to the second bearing unit 300 and comprises a pin 356 and comprises an abutment which can be formed by a recess 352 and a sleeve 354 situated in the recess 352. In the abutment, the pin 356 can perform a movement corresponding to the orbital path.

[0091] According to the embodiment shown, the abutment can be formed in the second bearing unit 300 and the pins 356 protrude from the first side 101 of the first spiral unit 100 and engage the abutment of the second bearing unit 300. A ring-pin coupling pair 351 can have a connecting bore 360 which perforates the second bearing unit 300 or the main bearing housing 302.

[0092] It can also be seen from FIG. 2 that the first spiral rib 110 on the second side 102 of the first spiral unit 100 forms the spiral channel 120 with a spiral channel base. At the end face, the spiral rib 110 also has a first spiral rib tip, which can either have a seal or be designed as a flat tip. Furthermore, the first spiral channel 120 can have an inner end region 125 and/or an outer end region 126.

[0093] The first spiral rib 110 is involute-shaped and extends from the inner end region 125 to the outer end region 126. The inner end region 125 is located radially on the inside relative to the longitudinal axis X and the outer end region 126 is located radially on the outside relative to the longitudinal axis X. The at least one spiral channel 120 is U-shaped and is delimited in the radial directions by the spiral rib 110 or a spiral wall of the spiral rib 110 and by the spiral channel base.

[0094] The second spiral unit 200 can be stationary and has a first side 201 and has a second side 202 which is opposite the first side 201 in the longitudinal axis X. A second spiral rib 210 protrudes in the longitudinal axis X on the first side 201, the second spiral rib 210 forming a second spiral channel 220.

[0095] At the end face, the second spiral rib 210 also has a second spiral rib tip, which can either have a seal or be designed as a flat tip. Furthermore, the second spiral channel 220 can have an inner end region 225 and/or an outer end region 226.

[0096] The second spiral rib 210 is adapted to the first spiral rib 110 and is also involute-shaped and extends from the inner end region 225 to an outer end region 226. The inner end region 225 is located radially on the inside relative to the longitudinal axis X and the outer end region 226 is located radially on the outside relative to the longitudinal axis X. The at least one second spiral channel 220 is U-shaped and is delimited in the radial directions by the second spiral rib 210 or a spiral wall of the second spiral rib 210 and by the second spiral channel base.

[0097] As shown in FIG. 2, the first spiral rib 110 of the first spiral unit 100 and the second spiral rib 210 of the second spiral unit 200 engage or mesh with one another. The first spiral unit 100 can be moved through the drive unit 400 along an orbital path (not shown) relative to the second spiral unit 200. A ring-pin coupling 350 prevents the first spiral unit 100 from rotating about the longitudinal axis X while moving along the orbital path.

[0098] Upon engaging or meshing with one another, the first spiral rib 110 engages the second spiral channel 220 and the second spiral rib 210 engages the first spiral channel 120. The second spiral rib tip of the second spiral rib 210 sealingly interacts with the spiral channel base of the first spiral unit 100 and the first spiral rib tip of the first spiral rib 110 interacts with the spiral channel base of the second spiral unit 200.

[0099] In a compressor, as the first spiral unit 100 moves along the orbital path between the first spiral unit 100 and the second spiral unit 200, pressure chambers (not shown) are enclosed through which medium is transported from the outer end regions 126, 226 to the inner end regions 125, 225. The outer end regions 126, 226 together form the suction region 320, from which the medium can be sucked into the spiral channels 120, 220 in order to then be transported in closed pressure chambers (not shown) from the outer end region 126, 226 to the inner end region 125, 225, the pressure chambers undergoing a continuous reduction in volume.

[0100] In an expander, as the first spiral unit 100 moves along the orbital path between the first spiral unit 100 and the second spiral unit 200, pressure chambers (not shown) are enclosed which transport medium from the inner end regions 125, 225 to the outer end regions 126, 226. During this process, the pressure chambers undergo a continuous increase in volume.

[0101] The medium is guided in the machine housing 10 along a plurality of flow paths from the inlet 11 to the outer end regions 126, 226, the medium being used along these flow paths to cool the components in the machine housing 10 and/or to lubricate them by means of entrained lubricant. In FIGS. 2-5, the flow paths are indicated by arrow lines; for better understanding only some of the arrow lines are marked with the reference sign S.

[0102] The medium enters the machine housing 10 through the inlet 11 into the inlet portion. The medium then flows from the inlet portion into the drive portion.

[0103] In the inlet portion, the medium branches and flows along two flow paths connected in parallel toward the drive portion, one of the flow paths extending through the first bearing unit 550 and the other flow path being guided through the drive shaft 420 or through the hollow shaft portion 424 of the drive shaft 420.

[0104] The medium can flow from the hollow shaft portion 424 into the drive portion through the radial bore 428 of the drive shaft 420. The drive shaft 420 can have one or more radial bores 428 both between the first bearing unit 450 and the rotor 410 and between the rotor 410 and the second bearing unit 300, as a result of which the flow path guided through the hollow shaft portion 424 branches several times and is used for cooling and/or lubrication, for example, of the rotor 410, the first bearing unit 300 and/or the second bearing unit 450.

[0105] Furthermore, it can be seen from FIG. 2 that the drive unit 400 has at least one axial opening 414 and/or at least one axial groove 418, which each guide a flow path through the drive unit 400. Each axial opening 414 and each axial groove 418 connects the two opposite end faces of the drive device 400, as a result of which the drive unit 400 is flushed with the medium. Very effective cooling of the drive unit 400 can be realized by this measure.

[0106] The at least one axial opening 414 can be formed by a passing gap between the rotor 410 and the stator 415.

[0107] From the drive portion, the medium then flows along a plurality of flow paths through the second bearing unit 300 into the suction region 320.

[0108] The medium can be guided via the space 380 to the suction region 320 and can be guided via the connecting bore 360 in the ring-pin coupling 350 or in the at least one ring-pin coupling pair 351.

[0109] The medium can be guided from the inlet 11 into the space 380 along two flow paths connected in parallel, one of the flow paths extending through the entry openings 370 and the other of the flow paths extending through the main bearing body 305. In this way, the main bearing body 305 can be both cooled and lubricated by the lubricant entrained with the medium.

[0110] In the space 380, the medium flows around the compensating mass 430 and the eccentric drive 150 of the first spiral unit 100, as a result of which these components can be both cooled and lubricated.

[0111] The medium can leave the space 380as can be seen from the enlarged view according to FIGS. 3 and 5through the exit openings 390, which connect the space 380 to the suction region 320 or to the outer end regions 126, 226 of the first spiral unit 100 and the second spiral unit 200. The exit openings 390 open into the suction region 320 on the second side of the second bearing unit 300, which side faces the first spiral unit 100, each exit opening 390 preferably opening within a surface that is fully or partially traversed by the first spiral unit 100 when said unit moves completely along the orbital path. The positions at which the exit openings 390 open allow the first side of the first spiral unit 100 or the axial bearing 190 to be lubricated by the lubricant entrained by the medium.

[0112] In order to avoid damage to the exit opening 390 and/or the axial bearing surface of the first spiral unit 100, the first spiral unit 100as shown in FIG. 3can have, on the side facing the at least one exit opening 390, a recessed portion 290 which is arranged within a surface which traverses the at least one exit opening 390 during a complete movement along the orbital path. In this way the exit opening 390 and the first spiral unit 100 do not come into contact.

[0113] A flow path can be guided from the drive portion and the suction region 320 through the ring-pin coupling 350 or the ring-pin coupling pairs 351. Each ring-pin coupling pair 351 can have a connecting bore 360 (see FIG. 5) which guides a further flow path coming from the inlet 11 to the suction region 320. For this purpose, the connecting bores 360 perforate the second bearing unit 300 and connect the first side of the second bearing unit 300 to the recess 352 in the first spiral unit 100. The pressure drop of the medium can be reduced by the connecting bores 360 in the ring-pin coupling pairs 351.

[0114] According to a development (not shown), at least one connecting bore 360 can be provided which perforates the second bearing unit 300 between two ring-pin coupling pairs 351 and guides a flow path from the inlet 11 to the suction region 320.

[0115] According to a development (not shown), the exit openings 390 can be formed by a plurality of radially oriented axial cut-outs arranged in the second side of the second bearing unit 300.

[0116] The axial cut-outs can extend over the second side of the second bearing unit 300 and thus also over the axial bearing 190 formed between the second bearing unit 300 and the first spiral unit 100. The lubricant entrained in the medium can contribute to lubricating the axial bearing 190 when the first spiral unit 100 traverses the recessed regions.

[0117] Furthermore, this development can comprise an axial bearing element which can be arranged in the form of a plate between the second bearing unit 300 and the first spiral unit 100. The axial bearing element is preferably an axial bearing plate.

[0118] In the two exemplary embodiments described above, the high-pressure chamber 30 and the intermediate bottom 50 are arranged on the second side 202 of the second spiral unit 200, the intermediate bottom 50 being arranged along the longitudinal axis X between the high-pressure chamber 30 and the second spiral unit 200. The intermediate bottom 50 decouples the second spiral unit 200 from the pressure forces in the high-pressure chamber 30 and is supported with respect to the machine housing 10.

[0119] The high-pressure chamber 30 is connected to the second spiral channel 220 via a passage 260, the passage 260 comprising an outlet opening which is arranged in the region of the inner end regions 125, 225. The outlet opening, also known as the discharge port, is preferably formed in the inner end region 225 of the second spiral channel base and the passage 260 extends along the longitudinal axis X through a through-hole through the intermediate bottom 50 to the high-pressure chamber 30.

[0120] The high-pressure chamber 30 is in turn connected to the outlet 12 and the medium can leave the scroll machine 2 through the outlet 12.

[0121] The high-pressure chamber 30 is surrounded or housed by the machine housing 10 and the intermediate bottom 50 and has the outlet 12 through which the medium can leave the scroll machine. For this purpose, the machine housing 10 or the second housing part 10 can be cup-shaped and have a recess, it being possible for the intermediate bottom 50 to close the high-pressure chamber 30 in the machine housing 10 or the second housing portion 10 in the manner of a cover or plug. For this purpose, the shapes of the recess in the second housing portion 10 and in the intermediate bottom 50 are adapted to one another, with both the recess and the intermediate bottom 50 preferably having a circular-cylindrical shape and being able to fit together precisely.

[0122] In order to avoid leakage between the intermediate bottom 50 and the machine housing 10, sealing means can be provided there.

[0123] The intermediate bottom 50 has a first side and a second side, the first side being nearest the second spiral unit 200 and the second side being nearest the high-pressure chamber 30. The intermediate bottom 50 comprises the through-hole through which the passage 260 extends.

[0124] In the embodiment shown, the intermediate bottom 50 has an annular projection protruding on the first side of the intermediate bottom 50 in the longitudinal axis X from the first side of the intermediate bottom 50 toward the second spiral unit 200.

[0125] On the first side of the intermediate bottom 50, there can be an axial securing means in the form of a securing ring which is fastened in the machine housing 10 and by means of which the position of the intermediate bottom 50 in the longitudinal axis X is determined. The axial securing means supports the intermediate bottom 50 on the side of the machine housing 10 facing the second spiral unit 200, as a result of which the pressure forces from the high-pressure chamber 30 are substantially decoupled from the second spiral unit 200 and coupled into the machine housing 10.

[0126] The second spiral unit 200 can telescopically embrace the annular projection of the intermediate bottom 50 and for this purpose has, on the second side 202, a first annular projection and a second annular projection, the first annular projection interacting with an inner lateral surface of the annular projection and the second annular projection interacting with an outer lateral surface of the annular projection of the intermediate bottom 50.

[0127] The annular projection of the intermediate bottom 50 and the annular projections embracing the annular projection of the intermediate bottom 50, on the second side 202 of the second spiral unit 200, do not necessarily have to be provided, but rather represent a preferred development that can be used in particular when the scroll machine 1 has an injection system or an eco-port.

The annular projections of the intermediate bottom 50 and the annular projections of the second spiral unit 200 can form a radial bearing for the second spiral unit 200.

[0128] As shown by the arrows in FIG. 2, the medium can reach the outlet 12 from the high-pressure chamber 30 via a pressure connection piece 40, the pressure connection piece 40 preferably being arranged in such a way that the medium cannot flow directly from the passage 260 into the pressure connection piece 40.

[0129] The pressure connection piece 40 projects from the side of the machine housing 10 facing the intermediate bottom 50, in the direction of the intermediate bottom 50 and, as shown in FIG. 7, is offset from the passage 260 in a plane perpendicular to the longitudinal axis X.

[0130] In order to bring about a particularly effective reduction of pressure fluctuations in the high-pressure chamber 30, a back-flow region 45 can be provided, which forces an S-shaped flow path S from the passage 260 through the pressure connection piece 40 to the outlet 12, which is indicated in FIG. 2 by an arrow line.

[0131] The back-flow region 45 can have, on the second side of the intermediate bottom 50 facing the high-pressure chamber 30, a preferably annular recess 59 (see FIG. 6) which together with the pressure connection piece defines the S-shaped flow path. For this purpose, the pressure connection piece 40 is in operative contact in a contact region 46 with the intermediate bottom 50 as shown in FIG. 6, the contact region 46, on an imaginary connecting line, being located between the pressure connection piece 40 and the passage 260 in a plane perpendicular to the longitudinal axis X. As a result, the medium coming from the passage 260 must first be deflected in order to flow into the recess 59 and from the recess to reach the outlet 12 through the pressure connection piece 40.

[0132] A non-return valve 48 shown in FIG. 2 can be arranged between the high-pressure chamber 30 and the outlet 12 and preferably comprises a bushing 49 that can be inserted into the pressure connection piece 40.

LIST OF REFERENCE NUMERALS

[0133] 1 Refrigeration system [0134] 2 Scroll machine [0135] 3 Condenser [0136] 4 Expansion element [0137] 5 Evaporator [0138] 10 Machine housing [0139] 11 Inlet [0140] 12 Outlet [0141] 30 High-pressure chamber [0142] 40 Pressure connection piece [0143] 45 Back-flow region [0144] 46 Contact region [0145] 49 Bushing [0146] 50 Intermediate bottom [0147] 100 First spiral unit [0148] 101 First side [0149] 102 Second side [0150] 110 First spiral rib [0151] 120 First spiral channel [0152] 125 Inner end region [0153] 126 Outer end region [0154] 150 Eccentric drive [0155] 152 Eccentric shaft portion [0156] 155 Eccentric bearing body [0157] 190 Axial bearing [0158] 200 Second spiral unit [0159] 201 First side [0160] 202 Second side [0161] 210 Second spiral rib [0162] 225 Inner end region [0163] 226 Outer end region [0164] 220 Second spiral channel [0165] 260 Passage [0166] 290 Recessed portion [0167] 320 Suction region [0168] 300 Second bearing unit [0169] 302 Main bearing housing [0170] 305 Main bearing body [0171] 350 Ring-pin coupling [0172] 351 Ring-pin coupling pair [0173] 352 Recess [0174] 354 Sleeve [0175] 356 Bolts [0176] 360 Connecting bore [0177] 370 Entry opening [0178] 380 Space [0179] 390 Exit opening [0180] 392 First bore portion [0181] 394 Second bore portion [0182] 400 Drive unit [0183] 410 Rotor [0184] 414 Axial groove [0185] 415 Stator [0186] 418 Axial opening [0187] 420 Drive shaft [0188] 424 Hollow shaft portion [0189] 428 Radial bore [0190] 430 Compensating mass [0191] 450 First bearing unit [0192] 452 Bearing holder [0193] 455 Secondary bearing body